JP6808257B1 - Method for producing brown sugar with reduced acrylamide and its source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce acrylamide of brown sugar and its production source without lowering the flavor as compared with ordinary brown sugar, and which can be easily applied at a manufacturing site of a brown sugar factory without requiring a cooling step or the like. I will provide a. SOLUTION: The brown sugar production method includes a juice squeezing step, a pretreatment heating step, a precipitation step, a concentration step, and a finish heating step of 120 ° C. or higher, which is before the finish heating step and after the concentration step. Provided is a method for producing brown sugar in which acrylamide and its production source are reduced, which comprises a step of performing asparaginase treatment at 60 to 75 ° C. for high syrup having a Brix value of 60 ° C. or higher. [Selection diagram] Fig. 2

Description

The present invention relates to a technique for producing acrylamide and brown sugar having a reduced source thereof. Specifically, it is a technique for reducing acrylamide and its production source of brown sugar without lowering the flavor as compared with ordinary brown sugar, and is a technique that can be easily applied at the manufacturing site of a brown sugar factory without requiring a cooling process or the like. Regarding.

In recent years, it has become clear that many processed foods contain acrylamide, and in April 2016, the Food Safety Commission published the results of the risk assessment. In addition to the fact that the toxicity of acrylamide is carcinogenic without a threshold value, it cannot be said that there is no concern about health effects in light of the amount of effects expressed in animal experiments, etc. It is strongly desired to reduce it. Therefore, guidelines for businesses and leaflets for consumers have been created and published by the Ministry of Agriculture, Forestry and Fisheries, and government departments are actively promoting risk management efforts.

Brown sugar, which is a special product of Okinawa, is a kind of honey-containing sugar produced by heating and concentrating sugar cane juice. It is eaten as it is as a confectionery because of its unique flavor, and it is also used as a material for confectionery and bakery. It is also used as a seasoning for home cooking.
Since sugar cane juice, which is a raw material for brown sugar, contains reducing sugar and asparagine, which are precursors of acrylamide, acrylamide is generated by high-temperature heating in the manufacturing process. According to a fact-finding survey by the Ministry of Agriculture and Fisheries, sugar-containing sugar and sugar-containing sugar It has been reported that relatively high concentrations of acrylamide are detected in confectionery containing sugar cane as a raw material.
The Food Health Impact Assessment Report compiled by the Food Safety Commission summarizes the estimated values of acrylamide intake of Japanese people derived from honey-containing sugar and products containing honey-containing sugar, and is calculated to be 2.4% of the total. ing. This figure is not considered to be small because the contribution of intake is dispersed among many items and it is necessary to make small efforts in each item to reduce the total intake.

It is recognized that reducing sugars and asparagine are present in raw materials or intermediate products as factors for producing acrylamide in foods, and that acrylamide is produced when these are exposed to high temperature conditions. According to the Ministry of Agriculture, Forestry and Fisheries' guidelines for reducing acrylamide in foods (1st edition) (Non-Patent Document 1), it is said that lowering the temperature conditions and shortening the heating time are effective measures to reduce acrylamide. ing.
However, acrylamide generated during heating in the food manufacturing process is a by-product of the aminocarbonyl reaction in which reducing sugars and amino acids react by heating, and the aminocarbonyl reaction is also a reaction that gives a food a favorable flavor. Therefore, when the heating is suppressed, the original flavor of the food is impaired, and it is not possible to produce a desired food that requires heating itself in the first place.

Regarding the reduction of acrylamide in foods, as a technique for reducing the acrylamide concentration in brown sugar, (i) asparaginase is added to sugar cane juice to reduce the asparagine concentration, and (ii) salts of calcium chloride and magnesium chloride are added. And (iii) methods such as adding amino acids of glycine and cystine can be mentioned.
However, all of these are examples of studies at the laboratory stage and cannot be applied in the actual brown sugar production process. Specifically, regarding (i), ordinary asparaginase available as a food additive is denatured and inactivated under normal heating conditions of 60 ° C. or higher, and therefore cannot be used under normal heating conditions (for example, Patent Documents). 1 Paragraph 0020). In this regard, in the brown sugar manufacturing process, the mixed solution containing sugar cane juice from the raw material sugar cane has the property of being extremely perishable, so it is necessary to immediately heat it for sterilization of microorganisms, deactivation of degrading enzymes, etc. From the viewpoint of preventing flavor deterioration, asparaginase treatment cannot be applied to the juice before heating. In addition, it is realistic to introduce a process of cooling a large-capacity tank or the like to a temperature at which the enzyme activity is guaranteed and adjusting the temperature at the intermediate stage of the factory plant at the site of mass production. Is difficult. In addition, if the temperature is lowered by cooling, there is a concern that the compositional change of sucrose to reduced sugar may occur due to the increase in residence time required for large-capacity temperature adjustment, and the quality such as flavor of brown sugar itself is guaranteed. In addition to not being cooled, reheating after enzyme treatment is required in addition to cooling itself, which significantly deteriorates the thermal economy and reduces production efficiency, and increases the viscosity of sucrose and concentrated sugar solution. There is concern about problems with pipes and tanks due to the precipitation of sucrose crystals.
Further, regarding (ii) and (iii), there is a problem that the flavor of brown sugar produced by the addition of salts and amino acids is changed or deteriorated.

Further, as another problem, when a food or drink which is a processed product accompanied by heating is produced from brown sugar as a raw material, a phenomenon is observed in which the heating process causes further acrylamide production, and the processed product further increases the acrylamide content. ..
Many of the above processed products are designed with the aim of appealing the flavor peculiar to brown sugar to consumers' tastes, so it is difficult to replace the raw material brown sugar with other sugars as a measure to reduce acrylamide. is there.

Special Table 2014-521355

Guidelines for reducing acrylamide in foods (1st edition), November 2013, Ministry of Agriculture, Forestry and Fisheries (Japan)

The present invention has been made in view of the above-mentioned circumstances of the prior art, and a subject matter thereof is a technique for reducing acrylamide of brown sugar and its production source without lowering the flavor as compared with ordinary brown sugar. It is an object of the present invention to provide a technology that can be easily applied at a manufacturing site of a brown sugar factory without requiring a cooling process or the like.

As a result of intensive research in the situation of the above-mentioned prior art, the present inventor imparts flavor as brown sugar in a normal brown sugar production process in which a juice squeezing step, a pretreatment heating step, a precipitation step, a concentration step, and a finish heating step are performed. It was found that most of the acrylamide contained in brown sugar is produced in the finish heating step.
Therefore, the present inventor has repeatedly studied the possibility of asparaginase treatment that can be practically applied in a brown sugar production plant. Then, a test was conducted in which asparaginase treatment was performed on a high sugar content sugar solution (high syrup) at a high temperature (60 ° C. or higher) after the concentration step immediately before the finish heating step. Surprisingly, the high syrup usually contains asparaginase. It was found that the enzyme activity was maintained high and the acrylamide content of the produced brown sugar was dramatically reduced in spite of the temperature range in which the enzyme activity was lost.
This phenomenon was considered to have occurred because the Brix value was just high because the concentration step was performed before the finish heating step to obtain high syrup in the normal brown sugar production step. Here, it was recognized that the high syrup at this stage was in a high temperature state of 60 to 75 ° C., and the enzyme activity of asparaginase was lost in a normal aqueous solution or buffer solution having a low Brix value.
In addition, it is recognized that the asparaginase treatment at this stage can be performed as it is without cooling using the tanks of existing factory plants, etc., and is most suitable for performing asparaginase treatment at the actual brown sugar production site. It was recognized as a stage. Furthermore, it was recognized that the amount of liquid to be treated was reduced through the concentration step and the concentration of asparagine, which is a substrate, was increased, which was also suitable for promptly advancing the enzymatic reaction.

Furthermore, as a result of repeated studies by the present inventor, the brown sugar produced by the above-mentioned production method showed a compositional feature showing an extremely low asparagine content and an extremely high molar ratio of aspartic acid to asparagine. In addition, when a sensory evaluation of flavor and appearance was performed on a group of subjects extracted from general consumers, an evaluation equivalent to or higher than that of normal brown sugar (brown sugar produced without asparaginase treatment) was obtained. Was done.
Further, when brown sugar syrup, which is a processed product accompanied by heating, is produced using the brown sugar, new production of acrylamide in the processed brown sugar product is extremely small even when the heat treatment required for the processing is performed. Was shown.

The present inventors have completed the present invention based on the above findings. The present invention specifically relates to the invention described below.
[Item 1]
A method for producing brown sugar, which comprises a squeezing step of raw sugar cane, a pretreatment heating step, a precipitation step, a concentration step, and a finish heating step of 120 ° C. or higher.
A step of performing asparaginase treatment at 60 to 75 ° C. for high syrup having a Brix value of 60 ° or more after the concentration step before the finish heating step.
A method for producing acrylamide and brown sugar having a reduced source thereof, which comprises.
[Item 2]
Item 2. The method for producing brown sugar according to Item 1, wherein in the method for producing brown sugar, from the pretreatment heating step to the completion of the finish heating step is performed at a temperature not less than 60 ° C.
[Item 3]
Item 2. The method for producing brown sugar according to Item 1 or 2, wherein the temperature of the asparaginase treatment is 64 to 70 ° C.
[Item 4]
Item 3. The method for producing brown sugar according to any one of Items 1 to 3, wherein the high syrup exhibits a Brix value of 65 to 75 °.
[Item 5]
Item 2. The method for producing brown sugar according to any one of Items 1 to 4, wherein the asparaginase treatment in the temperature range is carried out for 10 minutes or more so as to contain 200 ppm or more of asparaginase.
[Item 6]
Item 2. The method for producing brown sugar according to any one of Items 1 to 5, wherein the brown sugar is brown sugar having the compositional characteristics according to the following (A) and (B):
(A) The asparagine content is 1 mmol / kg or less.
(B) Aspartic acid is contained in a molar ratio of 3 or more with respect to asparagine.
[Item 7]
After producing brown sugar by the production method according to any one of Items 1 to 6,
A method for producing a processed brown sugar product, which comprises a step of heating the obtained mixture containing brown sugar and water.
[Item 8]
Item 7. The method for producing a processed brown sugar product according to Item 7, wherein the processed brown sugar product is a brown sugar syrup and has the compositional characteristics described in (A') and (B') below.
(A') Asparagine content is 1 mmol / kg or less,
(B') Aspartic acid is contained in a molar ratio of 3 or more with respect to asparagine.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a technique for reducing acrylamide of brown sugar and a source thereof without deteriorating the flavor, which can be applied at a manufacturing site of a brown sugar factory without requiring a cooling step or the like. Become.
According to the present invention, it is possible to produce brown sugar having a significantly reduced acrylamide content without changing the production plant, production equipment, etc. of the brown sugar factory. Further, in the present invention, even when the brown sugar is used as a raw material for a processed product such as brown sugar syrup, it is possible to produce a brown sugar processed product in which new acrylamide production accompanying the subsequent heat treatment is suppressed.

It is a flow chart which showed the main process (excluding asparaginase treatment) of brown sugar production in this test example. It is a result figure which compared the amount of acrylamide production by the difference in the presence or absence of asparaginase treatment with respect to high syrup in the production of brown sugar which concerns on Test Example 3. FIG. 2A: Result diagram in Test 3-1. FIG. 2B: Result diagram in Test 3-2. It is a photograph image of the appearance of the brown sugar produced in Test Example 3. Regarding the compositional characteristics of the brown sugar produced in Test Example 4, it is the result figure which compared the composition about asparagine and aspartic acid in acrylamide-reduced brown sugar and ordinary brown sugar. FIG. 4A: Result of asparagine concentration. FIG. 4B: Result diagram showing the molar ratio of aspartic acid / asparagine. In the figure, [Asp] indicates aspartic acid and [Asn] indicates asparagine. It is a result figure which compared the amount of acrylamide production by the difference of the raw material brown sugar in the production of brown sugar syrup which concerns on Test Example 5. It is a figure which showed the result of the sensory evaluation about the brown sugar syrup produced in Test Example 5. It is a figure which showed the relationship between the production of aspartic acid from asparagine by asparaginase, and the production of acrylamide from asparagine by heating.

Hereinafter, embodiments of the present invention will be described in detail. The technical scope of the present invention is not limited to the mode including all of the following configurations. In addition, the technical scope of the present invention does not exclude aspects including other configurations other than those described below.

[Definition of terms]
In the present specification, "brown sugar" refers to a type of "honey-containing sugar" produced by heating and concentrating sugar cane juice from sugar cane.
More specifically, it refers to a product manufactured by including the following basic steps from the viewpoint of quality such as flavor and appearance recognized as brown sugar. In order to produce honey-containing sugar recognized as "brown sugar" in Okinawa, which is a major production area of brown sugar, it is necessary to include the following basic steps.
On the contrary, the honey-containing sugar produced by the method not including the following basic steps is not included in the brown sugar in the present specification even if the acrylamide content is low. For example, those having a light color tone or low flavor obtained by performing the finish heating step at a low temperature of less than 120 ° C. (The product temperature at the time of heating does not reach 120 ° C. where the Maillard reaction is likely to occur and is insufficient. ) Is a honey-containing sugar, but does not correspond to brown sugar in the present specification.

In the present specification, the "ordinary brown sugar" used as the comparative sample of the embodiment refers to brown sugar produced by including the following basic steps without asparaginase treatment. Although the acrylamide content of the ordinary brown sugar has not been reduced, it is produced by including the following basic steps, and therefore falls under the definition of brown sugar in the present specification. Further, when a specific step is specified for brown sugar produced by performing asparaginase treatment, brown sugar produced in the same step without asparaginase treatment can be referred to as "ordinary brown sugar". .. Moreover, as a specific embodiment of the normal brown sugar in the embodiment, for example, brown sugar produced in the normal step of Test Example 3 can be mentioned.

In the present specification, the term "reduction" may be read as "reduction", "suppression", "inhibition", etc., depending on the context and content.
In the present specification, the term "sugar juice" is used as a term to refer to a juice squeezed from sugar cane and a processed liquid thereof. It can also be called sugar cane or sugar solution. Of the sugar cane juice, the sugar cane juice containing a large amount of impurities obtained in the juice squeezing process is sometimes called a mixed juice in particular. The high sugar content solution after the concentration step is particularly called high syrup.
In the present specification, the term "high syrup" refers to a high sugar content solution, and refers to an aqueous solution containing a high concentration of saccharides having a Brix value in the range of 60 ° to 75 ° after a concentration step on sugar cane juice. I am using it.

1. 1. Method for Producing Brown Sugar The present invention relates to a technique for producing brown sugar in which acrylamide and its production source are significantly reduced without changing the production plant or production equipment of the brown sugar factory.
Specifically, the present invention is a method for producing brown sugar, which comprises a juice squeezing step, a pretreatment heating step, a precipitation step, a concentration step, and a finish heating step of 120 ° C. or higher, and is concentrated before the finish heating step. The present invention relates to a method for producing brown sugar, which comprises a step of performing asparaginase treatment at 60 to 75 ° C. for high syrup having a Brix value of 60 ° or more after the step.
The production method according to the present invention is to perform asparaginase treatment, which was conventionally considered to be difficult to apply at the site of brown sugar production, as it is without cooling or the like using a tank or the like of an existing factory plant. Is the way it is possible. In this respect, the production method of the present invention does not exclude production in a small-scale production facility, but preferably a factory or the like in which the daily raw material pressing amount is 5 tons or more, more preferably 30 tons or more. It can be particularly preferably used in a large-scale manufacturing plant.

[Basic process in brown sugar production method]
The method for producing brown sugar according to the present invention includes the following squeezing step, pretreatment heating step, precipitation step, concentration step, and finish heating step of 120 ° C. or higher as basic steps.
In the method for producing brown sugar according to the present invention, an embodiment including steps other than these basic steps is also allowed. Further, although it is permissible to include other steps between each basic step, it is necessary to perform the steps after the squeezing step (from the pretreatment heating step to the completion of the finish heating step) at a high temperature.

In the production method according to the present invention, it is preferable that the step after the squeezing step (from the pretreatment heating step to the completion of the finish heating step) is performed at a temperature not less than 60 ° C.
On the other hand, a manufacturing process including a step of lowering the temperature than the temperature range (for example, a step of adjusting the temperature to a lower temperature and performing an enzyme treatment or the like) in any of the steps from the pretreatment heating step to the finish heating step in the following basic steps. In the case of, there is a concern that the compositional change of the sucrose content to the reducing sugar may occur due to the increase in the residence time, and the quality such as the flavor of the brown sugar itself cannot be guaranteed. Further, when such a low temperature step is included after the concentration step, piping troubles due to an increase in the viscosity of high syrup and crystal precipitation of sucrose are likely to occur, which is not suitable.
Even if the temperature temporarily drops below 60 ° C during each process or when moving pipes, the temperature is raised to 60 ° C or higher by heating in a short time in the temperature range of 50 to 60 ° C. When the above is recovered, it is acceptable as the manufacturing process of the present invention.

(Juice process)
As a method for producing brown sugar according to the present invention, a squeezing step of obtaining sugar cane juice from raw sugar cane is performed.
As the raw material sugarcane for producing brown sugar according to the present invention, a plant of a plant belonging to the genus Saccharum of the Gramineae family can be used. Here, as a plant belonging to the genus Saccharum, Saccharum officinarum (Officinalum species), Saccharum sinense (Sinense species) and the like can be preferably mentioned. From the viewpoint of the quality of brown sugar and the like, it is preferable to use a plant belonging to Saccharum officinarum (Officinalum species).
In addition, examples of sugarcane as a raw material for brown sugar production according to the present invention include varieties that belong to or are produced from these. It is also possible to use not only strains established as a group, but also plant individuals created by mating, mutation, gene transfer, genome editing, etc., and plant individuals such as F1 hybrids created by crossing. is there. More preferably, from the viewpoint of reducing the generation of acrylamide, it is preferable to use a variety line or a produced individual having a low reducing sugar content or asparagine content as a raw material sugarcane. Furthermore, it is also preferable to adopt a cultivation method in which the reducing sugar content and the asparagine content are reduced during the harvesting period.

As a raw material for the juice squeezing process, the sugarcane plant is used. Specifically, it is preferable to use the above-ground part of the plant body, and it is preferable to use the stem excluding the treetop head and leaves of the above-ground part of the plant body. In particular, it is preferable to use stalks in the ripening period in which the sugar content and the pure sugar content at the time of squeezing are high.
In the juice squeezing process, sugar cane juice is obtained from the plant body. Specifically, the plant body is subjected to a treatment such as shredding or crushing, and the operation of squeezing the plant body is performed to efficiently obtain sugar cane juice. It is desirable that the obtained sugar cane juice be separated and recovered from the squeezed residue (bagasse) of the plant body.
Further, in the juice squeezing step, in order to increase the juice squeezing rate, it is also preferable to add water to the juice slag and further squeeze it to obtain sugar cane juice.
Since the sugar cane juice obtained in the squeezing process contains various impurities such as bagasse pieces and water injection, it is called a mixed juice in order to distinguish it from the sugar cane juice in other processes. Sometimes.

In the brown sugar production method of the present invention, it is not preferable to perform asparaginase treatment on the mixed juice immediately after the juice squeezing step. At first glance, the mixed juice at this stage seems to be suitable for asparaginase treatment because the product temperature is room temperature, which is the active temperature of asparaginase. However, since the mixed juice contains enzymes such as conversion enzymes that decompose sucrose into reducing sugars and various microorganisms that promote putrefaction, it is necessary to extremely shorten the residence time until the pretreatment heating step for sterilization. is there. On the other hand, since the concentration of asparagine, which is a substrate of asparaginase, is dilute, it is necessary to increase the residence time after adding asparaginase to the mixed juice, which is accompanied by a significant deterioration in the quality of sugar cane juice due to putrefaction. Therefore, the mixed juice after the squeezing step is not suitable for asparaginase treatment in brown sugar production.

(Pretreatment heating process and precipitation process)
In the brown sugar production method according to the present invention, a pretreatment heating step and a precipitation step are performed on the mixed juice (sugar cane juice containing various impurities) obtained in the juice squeezing step.
Here, the steps from the pretreatment heating step to the cooling and stirring after the finish heating need to be performed while maintaining a high temperature state. Further, even when the liquid is passed through the pipe between each process, it is necessary to maintain the high temperature state. It is preferable to carry out the process at 60 ° C. or higher (when the temperature temporarily reaches 50 to 60 ° C., the temperature is quickly restored to 60 ° C. or higher) including these steps and piping liquid flow between steps. If the temperature is too low, the sugar cane juice is likely to spoil or deteriorate in quality due to the propagation of various germs, and piping troubles due to an increase in the viscosity of the sugar cane juice are likely to occur, which is not suitable.

As an embodiment of the pretreatment heating step, a step of performing a two-step heat treatment for different purposes on the mixed juice is preferable. Further, the step may be accompanied by pH adjustment.
As the first-stage heat treatment (first heat treatment) in this embodiment, inactivation of the converting enzyme contained in the mixed juice and sterilization of microorganisms are performed. Examples of the heat treatment include heat treatment at 65 ° C. or higher, but from the viewpoint of suppressing decomposition of the saccharide itself, the heat treatment is carried out at 65 to 95 ° C., preferably 68 to 85 ° C., more preferably 70 to 80 ° C. Is preferable.
As the second stage heat treatment (second heat treatment), the next precipitation step is facilitated by heating to a higher temperature than the first stage to reduce the viscosity of the mixed juice and promote the formation of a precipitate. It becomes possible to do it. The heat treatment may be in the range of 100 to 110 ° C., but is preferably performed at 102 to 105 ° C. Since the mixed juice is pumped by pumping to create a positive pressure inside the pipe, the sugar cane juice is pressurized and heated for a short time at a temperature exceeding the boiling point without performing a special pressurizing operation. It is possible. When the pressure heat treatment is additionally performed, the air contained in the fine particles such as bagasse pieces can be removed when the pressure is reduced to the atmospheric pressure in the next precipitation step, and the fine particles are more reliably precipitated. It becomes possible.

Here, the mixed juice shows a pH (pH 4.5 to 5.7) in an acidic range where sugar is easily decomposed. Therefore, in the pretreatment heating step, it is desirable to adjust the pH of sugar cane juice in the acidic range from the neutral range to weakly alkaline. The means for adjusting the pH is not particularly limited as long as it is a means for raising the pH, but as a means usually used in the production of brown sugar, for example, lime milk (in addition to dissolving calcium hydroxide in water) Means for adding (suspended) or the like can be mentioned. The lime milk may be added in the mixing tank or in the pipe in the middle of the flow path. The adjusted pH is preferably adjusted to pH 6.8 to 8, preferably pH 7 to 7.6.
The pH adjustment in this step is also called a liming step. Here, the rimming step is a method performed before the first stage heating (cold rimming) as a part of the pretreatment heating process, and a method performed between the first stage heating and the second stage heating (intermediate rimming). , It is possible to carry out by any of the methods (hot rimming) performed after the second stage heating, but in the production of brown sugar, intermediate rimming or hot rimming that can always keep the product temperature high is preferable. Is.

By allowing the sugar cane juice after the pretreatment heating step to stand at a high temperature, it is possible to precipitate impurities. In the precipitation step, aggregated proteins and fine particles produced by the above heat treatment are precipitated. The settling step is performed in a continuous settling tank (clarifier) and is also called a clarifier step.
In the precipitation step, it is necessary to promote the precipitation by allowing it to stand for a long time. Therefore, it is preferable to maintain a high temperature state in terms of clarifying the supernatant. For example, it is preferable to maintain a high temperature of 80 to 100 ° C., preferably 90 to 96 ° C. for standing. As the standing time, for example, the average residence time of the clarifier may be 1.5 to 6.5 hours, more preferably 2 to 3 hours.
After the precipitation step, the clarified supernatant and the precipitate are separated. The separation means does not exclude means such as filter filtration and centrifugation removal of sediment, but assuming processing in a large-scale factory plant or the like, piping is arranged on the side wall of the container in which the precipitation process is performed. Then, it is preferable to separate the clarified sugar cane juice (supernatant) by passing the supernatant through the pipe through the container for the next step.

(Concentration process)
In the brown sugar production method according to the present invention, a concentration step is performed on the clarified sugar cane juice obtained in the above step. After the concentration step, the sugar cane juice becomes a high syrup with a significantly increased sugar content.
In the concentration step, the clarified sugar cane juice is further heat-treated to evaporate the water content in the sugar cane juice. The heat treatment is preferably carried out under reduced pressure heating conditions from the viewpoint of efficient water evaporation and prevention of decomposition of sucrose due to overheating. That is, it is preferable that the concentration step is performed as a vacuum concentration step.
In a factory plant or the like, the concentration step can be performed using a heated vacuum vessel (vacuum distillation can or the like). Further, in this embodiment, the evaporation cans are connected in series by pipes to gradually increase the degree of decompression, the boiler steam is sent to the most upstream evaporation can, and the steam evaporated from the upstream evaporation can is used as a heat source for the downstream evaporation can. It can be suitably carried out in the mode of multi-can type vacuum concentration (multi-effect evaporation) to be used.
The concentration step is preferably carried out so that the product temperature of the sugar cane juice is 60 ° C. or higher, preferably 64 ° C. or higher. Further, in order to suppress the generation of acrylamide, it is preferable that the temperature is 100 ° C. or lower, preferably 90 ° C. or lower. The decompression conditions are not particularly limited, but in the case of a quadruple-effect can, the standard pressure is, for example, 0 kPa for No. 1 can, -13.6 kPa for No. 2 can, and -50.7 kPa, 4 for No. 3 can. A pressure condition such as −88.0 kPa for stepwise depressurization can be mentioned, but the pressure condition is not particularly limited to this condition.
After the concentration step, the sugar cane juice becomes high syrup (high sugar content sugar solution) in which the sugar concentration is significantly increased. As the Brix value of the high syrup, one having a Brix value of 60 ° or more is preferable from the viewpoint of maintaining high enzyme activity in asparaginase treatment. More preferably, a solution having a Brix value of 65 to 75 °, more preferably 68 to 73 ° is preferable.

(Finish heating process)
In the brown sugar production method according to the present invention, a finishing heating step is performed in which the high syrup is further heated under normal pressure conditions to evaporate the water content so that the product temperature becomes 120 ° C. or higher.
In the heat treatment in the finish heating step, the water content is significantly reduced and the product temperature becomes 120 ° C. or higher. Therefore, in the highly viscous liquid which is the concentrated high syrup, the flavor and color tone like brown sugar are imparted by the Maillard reaction or the like. Occurs. Heating with finish heating is also called cooking.
As the temperature of the finish heating step, it is preferable to heat the high syrup so that the product temperature of the highly viscous liquid becomes 120 to 140 ° C., more preferably 128 to 135 ° C. after the high syrup is in a low water state. .. By heating in the temperature range of the product temperature, flavoring and color tone addition are preferably performed.
Further, the finish heating step is preferably performed with stirring or mixing. When heating with stirring or mixing is performed, it is possible to prevent the reaction temperature from becoming too high in some parts, which is preferable in terms of reducing the production of acrylamide. The stirring or mixing can be performed continuously or intermittently. As a means of heat treatment in the finish heating step, specifically, assuming a factory plant or the like, it is possible to use a batch type open pan, a continuous type rototherm, an evaporator or the like. After the finish heating, the high syrup becomes a highly viscous liquid.

(Other processes)
The brown sugar production method according to the present invention preferably includes a stirring and cooling step of stirring the viscous liquid material under non-heating conditions after the finishing heating step. After this step, the composition and physical properties are such that the growth and putrefaction of microorganisms are unlikely to occur. Therefore, it is not necessary to maintain the product temperature at 60 ° C. or higher, and the product temperature can be cooled to room temperature or lower while maintaining the desired product form. It becomes.
In the stirring and cooling step, by continuing the stirring operation, the product temperature of the highly viscous liquid material is lowered, sugar crystals are precipitated, and sucrose microcrystals and honey are mixed. At this time, since the heat of crystallization of sucrose is released, the rate of decrease in the product temperature slows down and shows a temporary increase, which further promotes the evaporation of water and causes the highly viscous mud. After passing through a soft semi-solid substance, if stirring is continued as it is, it finally becomes a powdery substance. The stirring and cooling step can be processed into a desired product form by ending the sucrose crystals with arbitrary properties having different degrees of evaporation of water after precipitation and moving to the molding step. For example, it is possible to obtain a molded brown sugar product form by continuing stirring until it becomes a soft semi-solid substance in a stirring and cooling step, and then placing it in a frame or the like and cooling it to room temperature. In addition, the powdery product obtained by continuing sufficient stirring can be used as it is in a bag. Further, powdered sugar products having different particle sizes can be obtained by sieving and classifying the powdered material.
The brown sugar produced by the production method in this way can be in various forms such as a molded plate shape, a cracked lump shape, a crushed shape, and a powder shape.

[Asparaginase treatment process]
The method for producing brown sugar according to the present invention is characterized in that, in the production process including the above-mentioned basic process for brown sugar, a step of performing asparaginase treatment on high syrup after the concentration step, which is before the finish heating step, is included.

The asparaginase treatment according to the present invention is carried out on the high syrup obtained after the concentration step.
In the brown sugar production process, most of the acrylamide contained in brown sugar is produced in the finish heating step of imparting the flavor as brown sugar. On the other hand, in the high temperature (60 to 75 ° C.) high syrup after the concentration step immediately before the finish heating step of brown sugar production, the enzymatic activity of asparaginase is usually lost even though the enzymatic activity of asparaginase is lost. Is kept high, and the acrylamide content of the produced brown sugar can be significantly reduced.
Here, in the brown sugar production step, it is necessary to carry out the steps after the pretreatment heating step at 60 ° C. or higher, but the asparaginase treatment at this step can be carried out as it is without a cooling step or the like. ..
These findings are the first findings revealed in this example conducted by the present inventor.

The high syrup to be treated with asparaginase according to the present invention needs to be a high sugar content solution having a Brix value of 60 ° or more. The solution is a solution containing a high concentration of sucrose. In order to enable the asparaginase reaction to be carried out under a temperature condition of 60 ° C. or higher, the asparaginase treatment is carried out in a high sugar content solution in which the sugar content is significantly increased to a degree not expected under normal reaction conditions. The enzymatic reaction is carried out.
Here, as the Brix value of high syrup to be treated with asparaginase, 60 ° or more, 65 ° or more, 66 ° or more, 67 ° or more, or 68 ° or more can be preferably mentioned. The higher the Brix value, the more suitable it is from the viewpoint that the asparaginase enzyme activity is maintained high. Particularly preferably, a Brix value of 65 ° or more, 68 ° or more, or 68.3 ° or more can be preferably mentioned. On the other hand, when the Brix value is lower than a predetermined value, the asparaginase activity under high temperature conditions cannot be ensured, and the enzyme treatment target of the present invention cannot be used.
As the upper limit of the Brix value, 75 ° or less or 73 ° or less can be preferably mentioned. In particular, 72 ° or less can be preferably mentioned. If the Brix value is higher than the predetermined value, problems occur in the piping and the container due to crystal precipitation and an increase in viscosity in the high syrup, which is not desirable as the enzyme treatment target of the present invention.

The asparaginase treatment according to the present invention requires that high syrup having a product temperature of 60 to 75 ° C. be treated with an enzyme. The asparaginase treatment avoids problems due to increased viscosity due to temperature decrease and crystal precipitation of sucrose, and prevents deterioration of the thermal economy due to cooling and reheating when handling large volumes of solution in the process of brown sugar production after the pretreatment heating step. From the above viewpoint, it is preferable that the enzymatic reaction is carried out within a predetermined temperature range. In addition, from the viewpoint of preventing the compositional change of sucrose to reducing sugar due to the increase in residence time required for temperature adjustment of the large-volume solution (deterioration of product quality such as flavor due to poor sugar production due to crystallization inhibition), the predetermined temperature It is preferable to carry out the enzymatic reaction without causing a temperature drop that results in a lower temperature.
Here, as the temperature condition for performing the asparaginase treatment, 60 ° C. or higher, 61 ° C. or higher, 62 ° C. or higher, 63 ° C. or higher, or 64 ° C. or higher can be mentioned. The higher the temperature, the more suitable the temperature conditions are for the brown sugar production process. Particularly preferably, 65 ° C. or higher can be preferably mentioned. On the other hand, when the temperature is lower than the predetermined temperature, the above-mentioned problem cannot be avoided and it is not suitable for the enzyme treatment target of the present invention.
As the upper limit of the temperature condition of the asparaginase treatment, 75 ° C. or lower can be mentioned, but from the viewpoint of maintaining the asparaginase activity in high syrup, 72 ° C. or lower, preferably 70 ° C. or lower can be preferably mentioned.

Here, the temperature zone (60 to 75 ° C.) corresponds to a temperature zone in which asparaginase is inactivated and its activity is significantly lost in a normal aqueous solution or buffer solution having a low Brix value. For example, at 70 ° C., it is recognized that the activity of asparaginase is reduced to about 10 to 30% of the maximum activity in a normal aqueous solution or buffer solution in which Brix is not increased. Since the decrease in activity is due to irreversible denaturation of the enzyme protein, practicality cannot be expected even by extending the reaction time and / or increasing the amount of the enzyme. For example, Patent Document 1 relating to the reduction of acrylamide in honey-containing sugar, which is a prior art document, describes that the activity of asparaginase is lost at 60 ° C. or higher.

The asparaginase treatment according to the present invention does not exclude treatment on a small-scale reaction scale, but is preferably performed on high syrup having a liquid weight of a certain level or more. For example, it is preferable to perform the asparaginase treatment on high syrup having a liquid weight of 0.1 ton or more, 0.3 ton or more, or 0.5 ton or more.
In the present invention, the more the brown sugar is produced assuming a large capacity, the easier it is to obtain the advantage of avoiding the expected defects in the production process and the deterioration of quality when the temperature is lowered, and the asparaginase treatment step is achieved. This is a preferred embodiment in terms of effect.

As the asparaginase used for the asparaginase treatment, it is not necessary to use a special mutant enzyme or the like having high temperature resistance, and it is possible to use ordinary asparaginase approved for use in the production of foods.
Asparaginase is an enzyme that catalyzes the hydrolysis reaction of asparagine to aspartic acid. For example, those derived from Aspergillus oryzae (Aspergillus genus such as Aspergillus oryzae, Aspergillus niger) can be preferably used. In addition, as long as the enzyme activity in the above high syrup is guaranteed, the use of those derived from other organisms, mutant proteins, etc. is also permitted.
As the commercially available asparaginase preparation, for example, Acrylaway L of Novozymes, PresentASE M of DSM, and the like can be preferably used, but the present invention is not particularly limited thereto.

The amount or content of asparaginase added in the asparaginase treatment can be appropriately set in relation to the reaction time and the like. For example, 50 ppm or more, 100 ppm or more, 200 ppm or more, or 300 ppm with respect to the liquid weight of high syrup. It is preferable to add or contain the mixture so as to have the above concentration (w / w). The higher the added amount or content and the higher the enzyme concentration, the higher the asparagine reduction efficiency, which is preferable. Particularly preferably, 400 ppm or more can be preferably mentioned.
The upper limit of the addition amount or content of the asparaginase treatment can be 1000 ppm or less, but 500 ppm can be preferably mentioned from the viewpoint of optimizing the addition amount of the enzyme.
The reaction time of asparaginase in the asparaginase treatment can be appropriately set in relation to the addition amount or content of the enzyme, and the reaction is carried out so as to be, for example, 5 minutes or more, or 10 minutes or more. Aspects are preferred. As long as asparagine, which is a reaction substrate, is present in the high syrup, the longer the reaction time, the higher the efficiency of asparagine reduction, which is preferable. Particularly preferably, 15 minutes or more can be preferably mentioned.
The upper limit of the reaction time of the asparaginase treatment is not particularly limited, but within 6 hours or 2 hours when it is recognized that the substrate decomposition is sufficiently completed from the viewpoint of avoiding adverse effects on the composition due to being left for a long time. Within, or within 40 minutes can be preferably mentioned.

2. 2. Compositional Characteristics of Produced Brown Sugar In the above-mentioned method for producing brown sugar, it is possible to significantly reduce the amount of acrylamide produced from the finish heating step, which accounts for most of the acrylamide production (70% or more in the examples). That is, the brown sugar produced above is a brown sugar having a compositional feature with a reduced acrylamide content.
The asparaginase added in the production of brown sugar is irreversibly denatured when the product temperature exceeds 120 ° C. in the finish heating step, so that the enzyme activity of the produced brown sugar is completely lost. ..
Here, the acrylamide content of the brown sugar produced above may differ in the final production amount (absolute value) depending on the type of raw sugar cane, the temperature and time of heat treatment in the production process, and the like. However, when the acrylamide content of the brown sugar produced above is compared with and without asparaginase treatment under the same conditions, the value shows a significantly reduced value.
That is, the brown sugar according to the present invention exhibits the following compositional characteristics with respect to the acrylamide content:
Compared with the acrylamide content of normal brown sugar (brown sugar produced in the same manner in the above step without asparaginase treatment), the acrylamide content is 50% or less. Particularly preferably, those having a value of 45% or less or 40% or less can be preferably mentioned as the acrylamide-reduced brown sugar according to the present invention. Further, as the value, an embodiment having a value equal to or less than the value shown in Table 4 or 5 can be mentioned.

Further, the brown sugar produced as described above exhibits the property that the acrylamide content is simply reduced and the acrylamide producing ability is significantly reduced even when the brown sugar is subsequently heated. This characteristic is a compositional characteristic exhibited when the above-mentioned asparaginase treatment is performed, and is a compositional characteristic that cannot be exhibited by ordinary brown sugar production.
That is, the brown sugar according to the present invention exhibits the following compositional characteristics regarding amino acids with respect to the reduction of its acrylamide production source:
The asparagine content is 1 mmol / kg or less, and aspartic acid is contained in a molar ratio of 3 or more with respect to asparagine.

Here, it is generally recognized that the asparagine content of ordinary brown sugar is in the range of 10 to 100 mmol / kg, whereas the asparagine content of the brown sugar according to the present invention is significantly lower than that of ordinary brown sugar. Is shown.
That is, as the asparagine content of brown sugar according to the present invention, it is preferable that the asparagine content is 1 mmol / kg or less with respect to the mass of the produced brown sugar. Particularly preferably, those having an asparagine content of 0.8 mmol / kg or less or 0.6 mmol / kg or less can be preferably mentioned. The lower the value, the less asparagine, which is the source of acrylamide, and the compositional feature that the ability to produce acrylamide by subsequent heating is reduced. Further, as the relevant value, 0.57 mmol / kg or less, which is the numerical value shown in Table 6, can be preferably mentioned.
It should be noted that ordinary brown sugar is not expected to show a value of 10 mmol / kg or less (5 mmol / kg or less even considering the variation of the sample) in terms of the asparagine content contained in the raw sugar cane.

Further, in the brown sugar according to the present invention, the content value of aspartic acid shows a value that cannot be contained in ordinary brown sugar with respect to the amino acid ratio. The compositional properties can be shown as the molar ratio of aspartic acid to asparagine.
That is, in the brown sugar according to the present invention, it is preferable that the molar ratio of the aspartic acid content is 3 or more with respect to the asparagine of the produced brown sugar. Particularly preferably, the value having a value of 3.2 or more or 3.5 or more is preferable. The higher the value, the more the compositional feature that the ability to produce acrylamide by subsequent heating is reduced. Further, as the value, 3.8 or more, which is the numerical value shown in Table 6, can be preferably mentioned.
In addition, since ordinary brown sugar has a composition in which aspartic acid in the raw sugar cane is equal to or less than that of asparagine, the molar ratio may be 1 or more (2 or more even considering the variation of the sample). Not expected.

Further, the brown sugar produced above is preferably one that exhibits characteristics equal to or higher than those of ordinary brown sugar in terms of flavor components, appearance and the like.
In this respect, the brown sugar according to the present invention is evaluated to be equal to or higher than that of ordinary brown sugar when a preference-type sensory evaluation is performed on a group of subjects consisting of a sufficient number of people assuming general consumers. Those to be given can be preferably mentioned. When such an evaluation is obtained, in the brown sugar produced above, the properties related to acrylamide, asparagine, and aspartic acid show different values from those of ordinary brown sugar, while other compositional characteristics (flavor). And compositional characteristics related to appearance, etc.), it can be determined that brown sugar has a compositional characteristic equal to or higher than that of ordinary brown sugar.

That is, the brown sugar according to the present invention exhibits the following characteristics in terms of comprehensive evaluation of flavor and appearance:
When a sensory evaluation of flavor and appearance was performed on a group of subjects extracted from general consumers, 70% was compared with normal brown sugar (brown sugar produced in the same manner in the above step without asparaginase treatment). The above indicates the same or higher evaluation.
In the sensory evaluation, it is recognized that the larger the subject group, the more the evaluation that reflects the composition becomes possible. Therefore, as the subject group, it is preferable that the subject group is 50 or more, more preferably 100 or more, if the subject has not been subjected to sensory evaluation training.
Further, in the sensory evaluation, when the evaluation of equality or equality or higher with that of ordinary brown sugar is 70% or higher, 72% or higher, 75% or higher, 78% or higher, or 80% or higher, the flavor and appearance. It can be judged that it is suitable as a comprehensive evaluation of. Particularly preferably, the value indicating the sensory evaluation is 85% or more.
The higher the value of the sensory evaluation, the more it can be determined that the compositional characteristics related to flavor and appearance are brown sugar having a composition equal to or higher than that of ordinary brown sugar.

Here, in each of the production steps for producing brown sugar shown above, when asparaginase treatment is performed in another step, brown sugar exhibiting the above compositional characteristics cannot be obtained.
i) For example, when asparaginase treatment is applied to the mixed juice after the squeezing step, it is possible to reduce the production of acrylamide itself, but decomposition by a converting enzyme and putrefaction by microorganisms proceed. Therefore, the brown sugar has a composition in which the quality such as flavor is significantly reduced. Alternatively, due to a change in the composition in which the ratio of the reducing sugar that inhibits the crystallization of sucrose increases, the brown sugar cannot be produced even after the usual brown sugar production process.
ii) Further, since the sugar cane juice after the pretreatment heating step and before the concentration step shows a Brix value having a low sugar content, the asparaginase treatment cannot be performed under high temperature conditions of 60 ° C. or higher. Even if asparaginase is added at these stages, the reaction from asparagine to aspartic acid does not proceed, and acrylamide production in the subsequent finish heating step cannot be suppressed.
iii) In addition, if the temperature is lowered to less than 60 ° C. in any of the steps after the pretreatment heating step and the enzyme treatment is performed at a low temperature at which the activity of asparaginase is guaranteed, a large amount of temperature can be adjusted. There is a concern that the compositional change of the sucrose content to the reducing sugar may occur due to the increase in the required residence time, and the quality such as the flavor of the brown sugar itself cannot be guaranteed. In addition, the thermal economy required for cooling and reheating is significantly deteriorated, and the production efficiency is lowered, so that the sugar industry cannot be established.

3. 3. Production of Processed Brown Sugar Product The present invention includes an invention relating to the production of a processed brown sugar product using the brown sugar produced above.
The brown sugar produced as described above exhibits a characteristic that new production of acrylamide is significantly reduced even if the brown sugar is used as a raw material to carry out a manufacturing process of a processed product accompanied by heat treatment. That is, the brown sugar produced above exhibits the property that the acrylamide content itself is reduced and the acrylamide production during the heating is significantly reduced or suppressed even when the brown sugar is subsequently heated. .. That is, the brown sugar produced as described above exhibits a property in which the acrylamide production source is reduced and a property in which the acrylamide production ability is reduced.
In this respect, the present invention includes an invention relating to a method for producing a processed brown sugar product, which comprises a step of producing brown sugar by the production method described above and then heating the obtained mixture containing brown sugar and water. Here, the mixture is assumed to be a liquid substance, a viscous liquid substance, a gel-like substance, a muddy substance, a clay-like substance, a semi-solid substance, a solid substance, a mixed state of a solid substance and water, etc. in the manufacturing process of food and drink. Any shape or condition can be mentioned.
Further, the method for producing a processed brown sugar product according to the present invention is produced in the same process as a normal method for producing a processed brown sugar product, except that the acrylamide-reduced brown sugar produced above is used as the raw material brown sugar. It becomes possible.

As the processed brown sugar product according to the present invention, foods and drinks produced from brown sugar as a raw material can be preferably mentioned. In addition, it can be effectively used in the production of foods and drinks that are heat-treated in the production process.
For example, as the processed brown sugar product according to the present invention, brown sugar syrup that can be used as a seasoning or a raw material for a secondary processed product can be preferably mentioned. Further, even for the same food and drink, foods and drinks (particularly confectionery, bread, etc.) having a higher acrylamide concentration when honey-containing sugar is used as a raw material can be preferably mentioned as compared with the case where it is not used. As an example of the estimation of acrylamide intake by Japanese people conducted by the Food Safety Commission of the Cabinet Office, the processed foods include karinto (using sugar-containing sugar), bread rolls (using sugar-containing sugar), and manju (using sugar-containing sugar). ), Candies (using honey-containing sugar), etc. are described. Since the brown sugar produced by the present invention is a kind of honey-containing sugar, a large amount of acrylamide can be obtained by substituting the honey-containing sugar used in confectionery, bread, buns, and candy to which these foods belong. It can be reduced. In addition, the acrylamide reducing effect is similarly exhibited when used in the production of other foods and drinks.

In the present invention, when a processed brown sugar product that requires heat treatment is produced using the brown sugar (acrylamide-reduced brown sugar) produced above as a raw material, the amount of acrylamide itself contained in the raw material brown sugar is small. In addition, the new production of acrylamide is reduced or suppressed in the subsequent heating step during the production of the processed brown sugar product.
This characteristic is due to the fact that the content of asparagine, which is a source of acrylamide in the raw brown sugar, is significantly reduced by the asparaginase treatment during the production of the raw brown sugar.
In addition, the characteristics are similarly exhibited when a secondary processed product or a higher processed product that requires further heat treatment is produced using the brown sugar processed product (for example, brown sugar syrup, etc.) produced here. It is a characteristic to be manufactured.
Since asparaginase irreversibly loses its activity due to the rise in product temperature in the finish heating step, the asparaginase activity does not remain in the brown sugar produced above. Therefore, when a raw material containing asparagine is added as a raw material other than brown sugar in a processed brown sugar product, acrylamide due to asparagine derived from the raw material is produced. On the other hand, by using the brown sugar (acrylic mid-reduced brown sugar) produced above as a raw material, asparagine derived from brown sugar can be surely reduced. Therefore, even in a wide variety of processed brown sugar products, at least the amount of acrylamide derived from brown sugar is reduced. It will be reduced. Similarly, for processed brown sugar products produced from brown sugar syrup as a raw material, the same effect can be obtained by substituting brown sugar syrup produced from acrylamide-reduced brown sugar as a raw material.

As the processed brown sugar product according to the present invention, a mode of brown sugar syrup produced by immersing brown sugar in water and performing heat treatment can be preferably mentioned.
As an example of the embodiment relating to the production of brown sugar syrup, the acrylamide-reduced brown sugar produced above and water are mixed and dissolved by heating, and this is heated while stirring or mixing to add flavor and color. , A method for producing brown sugar syrup can be mentioned. Further, the brown sugar syrup according to the present invention can be produced by another production method as long as the acrylamide-reduced brown sugar produced above is used as the raw material brown sugar.
Here, since the brown sugar syrup is produced using the brown sugar produced above as a raw material, the composition of acrylamide (reduction rate with respect to the normal product), asparagine (content), and aspartic acid (molar ratio with aspartic acid). The characteristics are similar to the above-mentioned compositional characteristics of brown sugar. In addition, the compositional characteristics of flavor and appearance are similar to those of brown sugar described above.

4. Invention of Method The present invention includes the invention of various methods relating to brown sugar production, which comprises performing asparaginase treatment in the above-mentioned brown sugar production process.
The present invention includes, for example, a method for reducing or suppressing acrylamide production in the production of brown sugar or processed brown sugar, a method for reducing the acrylamide content in the production of brown sugar or processed brown sugar, and a method for reducing the source of acrylamide in brown sugar or processed brown sugar. Inventions relating to methods, etc. are included.
Various steps, conditions, methods, means, etc. relating to the invention of these various methods can be used by referring to or quoting the description in the above paragraph. Further, with respect to various processes, conditions, methods, means and the like other than the featured portion of the present invention, it is possible to adopt a conventional method or a known method.

Hereinafter, the present invention will be described with reference to examples, but the scope of the present invention is not limited thereto.

[Test Example 1] "Contribution to acrylamide production in each step in brown sugar production"
Regarding each process performed at the brown sugar production site, how each process is involved in acrylamide production was investigated.

(1) Production of brown sugar Brown sugar was produced at three brown sugar production plant plants in Okinawa Prefecture through the following steps. The outline of the process is shown in FIG. Here, in order to produce honey-containing sugar recognized as "brown sugar" by the Okinawa Prefecture Brown Sugar Cooperative, it is necessary to produce it through a predetermined process, but the production process of this example is a production method that matches this. Is.

1) Juice squeezing step A step of squeezing the raw material sugar cane to obtain a mixed juice (a vine juice containing various impurities) was performed. In this example, in order to increase the squeezing rate, the process was carried out using a quadruple squeezing machine, and squeezing was performed while injecting water into bagasse between the No. 3 mill and the final mill.
2) Primary heating process (primary juice heater: part of the pretreatment heating process)
Since the mixed juice contains enzymes such as conversion enzymes that decompose sucrose into reducing sugars and various microorganisms that promote putrefaction, a step of heating for enzyme inactivation and sterilization was performed. In this step, a multi-tube heater using steam as a heat source was used to heat the product to a temperature of about 75 ° C. in order to suppress the decomposition of sugars.
3) pH adjustment process (riming: part of pretreatment heating process)
Since the above mixed juice shows a pH in an acidic range where sugar is easily decomposed, the pH value is set to neutral to alkaline by adding lime milk (suspended by adding an amount of calcium hydroxide that is more than dissolved in water). The process of adjusting to was performed. In this step, the sugar cane juice having a pH of 5.5 to 5.7 was adjusted to pH 7 to 7.4 while the product temperature was maintained at about 75 ° C.
4) Second heating process (second juice heater: part of the pretreatment heating process)
The pH-adjusted mixed juice after rimming was heated to a temperature several degrees higher than the boiling point by a multi-tube heater using steam as a heat source. This step is a step necessary for ensuring the removal of precipitation of proteins and the like in the precipitation step (clarifier) of the next step. In this step, by heating at 103 to 105 ° C., which is higher than the boiling point under atmospheric pressure, it is possible to remove the air contained in the fine particles such as bagasse pieces when the pressure is reduced in the next step, and these fine particles can be removed. It ensures that it will settle.
5) Precipitation process (clarifier process)
After decompressing the above-mentioned pressurized and heated sugar cane juice to atmospheric pressure in a flash tank, the process was performed to clarify the sugar cane juice by allowing it to stand in a continuous settling tank (clarifier) to settle impurities. .. In this step, the precipitated protein, fine particles, etc. were removed by allowing the mixture to stand at 90 ° C. or higher.
6) Decompression and concentration step A step of collecting the clarified solution of the sugar cane juice that had undergone the above precipitation step and concentrating the sugar cane juice in a decompression tank was performed. In the factory of this example, four decompression evaporation cans (heated decompression concentration tanks) that can heat the sugar cane juice inside the can by heating with steam via a heat transfer tube arranged inside the can are installed in series. , Gradual decompression concentration by quadruple effect evaporation was performed. In the tank at the final stage of the process, the product temperature was about 60 ° C. and Brix 70 ° C. was high syrup.
7) Finish heating step After performing the above decompression concentration step, a finish heating step of evaporating water while heating the high syrup was performed. In this step, since the product is heated until the product temperature reaches 135 ° C. while evaporating the water content using an open pan or Roththerm, the product of the step is imparted with a flavor and color tone peculiar to brown sugar. The product after heating became a viscous liquid.
8) Cooling and stirring step A cooling and stirring step was performed in which the highly viscous liquid material was stirred to further evaporate water and precipitate crystals. By this step, the water content of the treated product was evaporated to form a soft, highly viscous mud-like product in which fine crystals of sucrose and honey were mixed. The product temperature was 80 ° C.
9) Solidification Step The highly viscous mud-like substance was formed into a plate, completely solidified, and then coarsely crushed to obtain solid sugar.

(2) Analysis of acrylamide production A sample was collected after each of the above steps was performed, and analysis of acrylamide production was performed. The quantification of acrylamide contained in each sample was performed using an LC-MS / MS apparatus (4000QTrap, manufactured by SIEX). In this analysis, the detection limit was 0.005 mg / kg or less and the quantification limit was 0.010 mg / kg or less.
Based on the quantitative values obtained in the analysis, the contribution rate of each step to acrylamide production with respect to the amount of acrylamide contained in the final product was calculated. The results are shown in the table below.
In the table, the total contribution rate of Factory A is insufficient by 3%, but it is estimated that this is the amount generated by the residual heat during cooling stirring. Further, in Factory C, a sample was collected from the secondary heating and concentrated under reduced pressure as one operation step, and the contribution rate was calculated.

As a result, it was shown that most of the acrylamide was produced during the heat treatment in the finish heating step in all of the three brown sugar manufacturing plants investigated. In particular, in Factory A, it was shown that 90% of the acrylamide contained in the final product is produced in the finish heating step. On the other hand, in the step prior to the finish heating, acrylamide formation was confirmed between the second heating step and the vacuum concentration step, but the amount of acrylamide produced was found to be about 1/4 or less of the total amount, and especially in factory A, 7 It was a small value of%.
From the above results, the factors that generate acrylamide in the brown sugar production process are not the heat treatment in the previous stage such as primary heating and secondary heating, but the presence of reducing sugars and amino acids in high concentrations and 120 ° C. or higher. It was shown that the contribution of the finish heating under the heating conditions of is the largest.
Therefore, it was shown that when acrylamide is reduced by using asparaginase treatment in the brown sugar production step, it is necessary to carry out the asparaginase treatment in the step prior to the finish heating.

[Test Example 2] "Examination of asparaginase treatment for each step of brown sugar production"
The possibility of reducing acrylamide by using asparaginase treatment was investigated for each process performed at the brown sugar production site.

(1) Mixed juice after the squeezing process It was examined to treat the mixed juice (sugar cane juice containing various impurities) immediately after the squeezing process with asparaginase treatment. In this step, since the product temperature was room temperature, an acrylamide reducing effect was expected in terms of the enzymatic activity of asparaginase.
However, since the mixed juice at this stage contains enzymes such as conversion enzymes that decompose sucrose into reducing sugars and various microorganisms, sugar cane juice is treated with asparaginase, which requires retention of sugar cane juice. Accompanied by quality deterioration. Therefore, it was recognized that the process was not suitable for asparaginase treatment at the site of the brown sugar manufacturing factory.

(2) Sugar cane juice after the first heating step Since the acrylamide production rate was low in the steps from the first heating step to before the finish heating step, the acrylamide reduction effect by the asparaginase treatment was expected.
However, in the plant of the brown sugar manufacturing factory, the steps after the first heating step are performed at a high temperature of 60 ° C or higher, and in these steps, the product temperature of the sugar cane juice greatly exceeds 60 ° C in which asparaginase is inactivated. Since the temperature reaches a high temperature of 75 to 105 ° C., the enzyme treatment cannot be performed as it is. In this respect, in order to carry out the asparaginase treatment, it is necessary to introduce a cooling facility or the like into a large-capacity tank or the like of a factory plant, and thus it is recognized that the process is not suitable at an actual manufacturing site. In addition, if the temperature of sugar cane juice, which is a large-volume solution, is lowered by cooling, there is a concern that the production efficiency will be significantly reduced due to the deterioration of the thermal economy required for cooling and reheating. In addition, there was a concern that the compositional change of sucrose to reducing sugar would occur due to the increase in residence time due to the temperature change of the large-volume solution. Further, in the high syrup after concentration under reduced pressure, there is a concern that when cooling is performed, a problem may occur in the piping or the like due to an increase in viscosity and crystal precipitation of sucrose.

(3) High syrup after concentration under reduced pressure As discussed in (2) above, it is difficult to introduce a cooling process in the intermediate stage in the brown sugar production process in terms of technical and production efficiency, and immediately before the finish heating process is performed. It is also necessary to maintain the product temperature at 60 ° C. or higher for the high syrup after the vacuum concentration step.
However, when the present inventor conducted an asparaginase activity test on high syrup collected from the tank after the vacuum concentration step, the asparaginase activity was exhibited at 60 to 70 ° C., which is a temperature range in which asparaginase is normally inactivated. It was shown to be done. The detailed test results are as follows.

High syrup (Brix 68.3 °, asparagine concentration 19.5 mmol / L) after the vacuum concentration step of Test Example 1 was collected, asparaginase was added at a concentration of 500 ppm (w / w), and it was a substrate at various temperatures. The decomposition rate of asparagine was measured. As the asparaginase used in this example, two commercially available asparaginases (manufactured by Acrylaway L Novozymes and manufactured by PreventASe M DSM) were used. In addition, the asparagine decomposition rate was measured by measuring the change over time in the amount of ammonia produced by the decomposition of asparagine from the color absorbance of phenol nitroprusside, and calculating the asparagine decomposition rate from the measured values. The results are shown in the table below.

As a result, in both of the two types of asparaginase (enzyme 1 and enzyme 2), the reaction rate of asparaginase was maximized at 60 ° C. and the maximum activity was not lost even at 70 ° C. in the high syrup of Brix 68.3 °. It has been shown that a reaction rate of 60-72% of activity is maintained.
Here, the temperature of 70 ° C. is recognized as a temperature at which the activity of asparaginase is reduced to about 10 to 30% of the maximum activity in a normal aqueous solution or buffer solution in which Brix is not increased. In this regard, Patent Document 1 relating to the reduction of acrylamide in honey-containing sugar, which is a prior art document, describes that asparaginase loses its activity at 60 ° C. or higher.
From the results, it is possible to perform asparaginase treatment without cooling in the high syrup after decompression concentration (immediately before finish heating) in the brown sugar production process even when the temperature is 60 to 70 ° C. Was shown.

In view of the above findings, in the brown sugar manufacturing process, the product temperature of high syrup after concentration under reduced pressure and immediately before finish heating is 60 to 70 ° C. Therefore, when asparaginase treatment is performed at this stage, cooling for temperature adjustment, etc. It was recognized that there was no need for. In this respect, it is recognized that the asparaginase treatment at this stage can be performed as it is using the tanks of existing factory plants, etc., and it is the most suitable stage for performing asparaginase treatment at the actual brown sugar production site. Admitted.

(4) Enzyme reaction time Asparaginase (manufactured by Acrylaway L Novozymes) was added to a tank filled with high syrup at about 65 ° C after concentration under reduced pressure, and the sample was stirred for 40 minutes at 5-minute intervals over time. The sample was collected, the amount of ammonia produced by the decomposition of asparagine was measured, and the asparagine concentration in the sample solution was calculated from the value. Various experimental conditions and measurement operations were carried out in the same manner as in (3) above.
As a result, the asparagine concentration decreased rapidly from the start of the reaction until 15 minutes later, and no subsequent decrease was confirmed. From the results, under the condition that asparaginase at a concentration of 500 ppm was added to high syrup (Brix 68.3 °, asparagine concentration 19.5 mmol / L, temperature 65 ° C.), most (85-97.6%) took about 15 minutes. ) Was shown to disappear.

[Test Example 3] "Demonstration test of asparaginase treatment in brown sugar manufacturing factory"
At the site of the brown sugar manufacturing plant, asparaginase treatment was applied to the high syrup after the vacuum concentration process before the finish heating process, and its acrylamide reduction effect was verified.

(1) Production of brown sugar treated with asparaginase At a brown sugar production plant in Okinawa Prefecture, brown sugar was produced in the same manner as in Test Example 1 except that high syrup at 60 to 70 ° C. after the vacuum concentration step was treated with asparaginase. To obtain brown sugar (the product of the present invention). In the asparaginase treatment, asparaginase (Acrylaway L Novozymes) has a concentration of 400 ppm (w / w) in 0.5 tons of high syrup (Brix value 70 to 72 °) after the vacuum concentration step before the finish heating step. (Manufactured) was added, and the reaction tank was maintained at about 65 ° C. and treated with asparaginase for 40 minutes while stirring.
Further, as a comparative example, brown sugar was produced in the same manner as in Test Example 1 without asparaginase treatment to obtain brown sugar (comparative product). The verification test was carried out twice with different production lots.

(2) Measurement of acrylamide content High syrup after the vacuum concentration step before the finish heating step and a part of brown sugar after the finish heating step in an open pan were collected as samples and the acrylamide concentration was quantified. The quantification of acrylamide contained in each sample was carried out in the same manner as in Test Example 1. The results are shown in the table below and FIG. Here, the acrylamide concentration of high syrup in the result is shown as a value converted per weight of the soluble solid content in high syrup. In addition, the total acrylamide indicates the acrylamide concentration in brown sugar. The amount produced in the finish heating step is a value calculated as the difference between them.
As a result, in both of the two brown sugar productions carried out in different production lots, when asparaginase treatment was performed on high syrup at 60 to 70 ° C. after the vacuum concentration step (the product of the present invention), enzyme treatment was performed. It was shown that the amount of acrylamide produced was significantly reduced as compared with the non-brown sugar (comparative product). Specifically, it was shown that the acrylamide content was reduced to 38.7% in Test 3-1 and to 34.2% in Test 3-2 compared to untreated brown sugar. ..

(3) Appearance of the produced brown sugar, etc. After the above finish heating step, the final product, brown sugar, was produced. The photographic image is shown in FIG. As a result, the acrylamide-reduced brown sugar (the product of the present invention) produced through the above-mentioned asparaginase treatment showed the same characteristics as the normal brown sugar (comparative product) that had not been subjected to the enzyme treatment in its appearance and color tone.

(4) Summary From the above results, it is possible to perform asparaginase treatment on high syrup at 60 to 70 ° C. after concentration under reduced pressure and immediately before finish heating without cooling in the brown sugar production process. Shown. Then, it was shown that by carrying out this treatment, acrylamide production in the finish heating step was suppressed, and brown sugar having a significantly reduced acrylamide content could be produced.
It was also shown that even when asparaginase treatment is performed, it can be produced as a product having an appearance and color tone suitable for brown sugar.

[Test Example 4] "Ratio of asparagine and aspartic acid in brown sugar"
The contents of asparagine and aspartic acid contained in the brown sugar produced above were measured, and the content ratios were calculated.

At a brown sugar production plant in Okinawa Prefecture, acrylamide-reduced brown sugar (product of the present invention: with asparaginase treatment) and normal brown sugar (comparative product: without asparaginase treatment) were produced in the same manner as in Test Example 3.
A part of brown sugar immediately after production was used as an analysis sample, and the contents of asparagine and aspartic acid contained in brown sugar were measured using a fully automatic amino acid analyzer. From the obtained measured values, the molar ratio of aspartic acid to asparagine contained in brown sugar was calculated. The results are shown in the table below and FIG.

As a result, it was shown that the ordinary brown sugar (comparative product) produced without asparaginase treatment contained an average of 14.35 mmol / kg of asparagine. Moreover, in the composition of brown sugar obtained by ordinary brown sugar production, the molar ratio of aspartic acid / asparagine showed an average of 0.211. The value was a value indicating that the composition had a significantly smaller content ratio of aspartic acid than that of asparagine.

On the other hand, it was shown that the acrylamide-reduced brown sugar (the product of the present invention) produced by asparaginase treatment contained 0.57 mmol / kg of asparagine. In this regard, in the composition of brown sugar (acrylamide-reduced brown sugar) produced by asparaginase treatment, the molar ratio of aspartic acid / asparagine was 3.8. This value was a value indicating that the content ratio of aspartic acid was significantly larger than that of asparagine.

From the above results, the brown sugar (the product of the present invention) produced by the asparaginase treatment showed a significantly lower asparagine content and a significantly higher aspartic acid content as compared with the normal brown sugar (comparative product). From this, the acrylamide-reduced brown sugar according to the present invention is clearly distinguished from ordinary brown sugar by the compositional characteristics regarding the molar ratio of asparagine and aspartic acid in addition to the compositional characteristics in which the acrylamide content is reduced. It was shown that it can be done.

[Test Example 5] "Production of brown sugar syrup (processed brown sugar) from acrylamide-reduced brown sugar"
A brown sugar syrup was produced using acrylamide-reduced brown sugar as a raw material and evaluated in various ways.

(1) Production of brown sugar syrup An acrylamide-reduced brown sugar that had been treated with asparaginase was produced in the same manner as in Test Example 3. In addition, as a comparative product, ordinary brown sugar was produced in the same manner except that asparaginase treatment was not performed.
Water was added to the obtained raw material brown sugar and heated to produce a brown sugar syrup. Specifically, 10 kg of brown sugar and 5 L of charged water were placed in a rotary kettle and heated to boil and dissolve, and the whole was boiled. Heat treatment was carried out in a rotary kettle for about 40 minutes to add flavor and color to obtain about 14.5 kg of brown sugar syrup.

(2) Measurement of acrylamide content A part of the syrup in the kettle was taken as a sample for the intermediate product and the final product in the heating process when brown sugar was dissolved, and the acrylamide concentration was quantified. The quantification of acrylamide contained in each sample was carried out in the same manner as in Test Example 1. The amount of acrylamide derived from the brown sugar raw material is a value obtained by converting the measured value of the acrylamide concentration at the time of dissolution into the same Brix value as the final product in consideration of the evaporation of the amount of water due to heating during the brown sugar syrup manufacturing process (at the time of dissolution). The Brix value of 65 ° is converted into the Brix value of 70 ° of the final product). The results are shown in the table below and FIG.

As a result, when a brown sugar syrup (comparative product) was produced using ordinary brown sugar as a raw material, the acrylamide content of the final product brown sugar syrup was 670 μg / kg. Here, in addition to 452 μg / kg, which is the acrylamide content at the time of dissolving the raw brown sugar (the amount produced during the production of the raw brown sugar), 218 μg / kg of acrylamide is newly generated in the heating step at the time of producing the brown sugar syrup. It was shown to do.
On the other hand, when brown sugar syrup (the product of the present invention) is produced using acrylamide-reduced brown sugar as a raw material, the acrylamide content of the final product brown sugar syrup is 180 μg / kg, which is 26.9% of the acrylamide content of the above-mentioned normal brown sugar syrup. It was shown that the acrylamide content was reduced.
Here, in addition to 151 μg / kg, which is the acrylamide content when the raw brown sugar is dissolved (the amount produced during the production of the raw brown sugar), only 29 μg / kg of acrylamide newly generated in the heating step during the production of brown sugar syrup. It was shown to be minutes.

From the above results, when a processed brown sugar product such as brown sugar syrup is produced using reduced acrylamide brown sugar as a raw material, in addition to the small amount of acrylamide itself contained in the raw material brown sugar, the subsequent processed brown sugar product such as brown sugar syrup It was shown that the new production of acrylamide was also reduced during the heating process during the production of.
It was recognized that this result was due to the fact that the content of asparagine, which is an acrylamide producing source, was significantly reduced by the asparaginase treatment during the production of raw brown sugar.

(3) Sensory evaluation The functional evaluation of the brown sugar syrup produced above was performed. About 100 brown sugar syrups produced using normal brown sugar (comparative product: normal brown sugar syrup) and brown sugar syrup produced using acrylamide-reduced brown sugar (invention product: acrylamide-reduced brown sugar syrup) under blind conditions. I handed it over to the tester and got answers about the following evaluation items. The results are shown in the table below. The results of the comprehensive evaluation are also shown in FIG.

(Color, aroma, and taste preference)
Regarding the evaluation of the color, aroma, and taste preference of brown sugar syrup, acrylamide-reduced brown sugar syrup is better than normal brown sugar syrup, there is no difference between the two, and the difference between the two is not noticeable. Answers accounted for about 95%, about 88%, and about 72%, respectively.

(Comprehensive evaluation)
Regarding the overall evaluation of brown sugar syrup as a product, about 85% of the respondents answered that acrylamide-reduced brown sugar syrup is better than normal brown sugar syrup, there is no difference between the two, and the difference between the two is not noticeable. It was.
From the above results, brown sugar syrup produced from acrylamide-reduced brown sugar is a product that can be accepted by the majority of consumers as a product equal to or better than ordinary brown sugar syrup in terms of color tone and flavor as brown sugar syrup. It was shown to be.

The present invention is expected to be used in the food industry field. The problem of reducing acrylamide in brown sugar production is an important issue for all food business operators that handle brown sugar, and the technique according to the present invention is a technique that can be used as it is by using the equipment of a conventional brown sugar manufacturing factory. .. Therefore, the technique according to the present invention is expected to become a technique that can be immediately used by a brown sugar producer, a brown sugar processing company using brown sugar, and the like.

Claims (6)

A method for producing brown sugar, which comprises a squeezing step of raw sugar cane, a pretreatment heating step, a precipitation step, a concentration step, and a finish heating step of 120 ° C. or higher.
A step of performing asparaginase treatment at 65 to 70 ° C. on high syrup, which is an aqueous solution containing sucrose having a high sugar content showing a Brix value of 68 to 72 ° after the concentration step before the finish heating step.
A method for producing acrylamide and brown sugar having a reduced source thereof, which comprises. The method for producing brown sugar according to claim 1, wherein in the method for producing brown sugar, from the pretreatment heating step to the completion of the finish heating step is performed at a temperature not less than 60 ° C. The method for producing brown sugar according to claim 1 or 2 , wherein the asparaginase treatment in the temperature range is carried out for 10 minutes or more so as to contain 200 ppm or more of asparaginase. The method for producing brown sugar according to any one of claims 1 to 3 , wherein the brown sugar is brown sugar having the compositional characteristics according to the following (A) and (B):
(A) The asparagine content is 1 mmol / kg or less.
(B) Aspartic acid is contained in a molar ratio of 3 or more with respect to asparagine. After producing brown sugar by the production method according to any one of claims 1 to 4 ,
A method for producing a processed brown sugar product, which comprises a step of heating the obtained mixture containing brown sugar and water. The method for producing a processed brown sugar product according to claim 5 , wherein the processed brown sugar product is a brown sugar syrup, which is a processed brown sugar product having the compositional characteristics according to the following (A') and (B'):
(A') Asparagine content is 1 mmol / kg or less,
(B') Aspartic acid is contained in a molar ratio of 3 or more with respect to asparagine.