JPS6265654A - Production of processing starch - Google Patents

Abstract

PURPOSE:To efficiently and economically obtain processing starch utilizable for various applications while preventing the quality deterioration thereof, by granulating starch to give granular starch and heat-treating the granular starch in the presence of superheated steam. CONSTITUTION:Starch, preferably wheat or barley starch, corn starch, potato starch, sweet potato starch, tapioca sorghum starch or chestnut starch, is granulated preferably in the presence of a binder, e.g. starch paste, to give granular starch, which is then heat-treated in the presence of superheated steam to afford the aimed processing starch.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing starch for processing, and in particular, to granulating starch into granular starch, which is heat-treated in the presence of superheated steam to prevent starch quality deterioration as much as possible. The present invention relates to a method for efficiently and economically obtaining processing starch that can be used for various purposes.

[Problem that the invention seeks to solve]

Conventionally, pregelatinized starch has been known as a type of starch for processing, and its manufacturing method involves adding water to starch to make an emulsion, heating it to gelatinize it, and then spreading it out into a film on the surface of a drum F dryer, etc. , a method of drying by heating, scraping, and pulverizing (hereinafter referred to as a drum dryer method), and a method of heat treatment using an extruder are known.

However, in the drum dryer method, the liquid must be heated and pregelatinized, and a large amount of water is required for operation, so a huge amount of thermal energy is required for drying. Also,
A feature of this treatment method is that it is difficult to appropriately control properties such as degree of gelatinization, degree of swelling, gel strength, etc. in accordance with the application and purpose of processing, and this has the problem of limiting the range of application.

In addition, the method of heat treatment using an extruder is
Heat treatment (gelatinization) can be performed all at once under conditions with little moisture, but the starch granules are destroyed during the pressure extrusion process, so if you use this dissolved in water, water will be absorbed too quickly and lumps will form. Easy to do. Considering that the texture of starch in foods such as bread and anchovies is greatly affected by the fact that the starch grains are not disintegrated, foods in which the starch grains are destroyed are unsuitable. . In addition, the processing capacity for starch is low compared to the size of the apparatus, and there is a problem that it is not suitable for processing large amounts of starch.

On the other hand, the starch for processing obtained in this way.

It does not require heat treatment when dissolved in water and has important physical properties in the food industry and other industries, such as becoming viscous immediately, so it is used as a food material as well as a thickener for various foods.

It is used as a water retention agent, quality improver, and excipient, as a coating agent and excipient for pharmaceuticals, and also as an industrial adhesive, and the demand for it has been rapidly increasing in recent years.

[Means to solve the problem]

Therefore, the present inventors have conducted various researches in response to the current situation, and have found that if starch is granulated into granular starch and then heat-treated in the presence of superheated steam, the above-mentioned drawbacks and It is possible to obtain starch without any problems economically and efficiently, and that when the starch is granulated in the presence of a binder in the above method, the granular starch becomes difficult to break; Based on this knowledge, if the surface moisture of the granular starch is high prior to the superheated steam treatment, drying can effectively (prevent) the granular starch from adhering to each other or to the inner wall surface of the apparatus during the superheated steam treatment. The present invention was completed.

That is, the present invention provides (1) granulating starch into granular starch;
(2) The starch is granulated in the presence of a binder to form granular starch, which is then heated in the presence of superheated steam. (a method for producing starch for processing, which is characterized by heat treatment in the presence of).

and (3) a method for producing starch for processing, which comprises granulating starch into granular starch, drying it, and then heat-treating it in the presence of superheated steam.

[Effect]

The present invention will be explained in detail below.

First, the starch used in the present invention is as follows.

Starch separated from wheat such as barley, wheat, and oats; corn (maize), g, millet, Il, )-! J
Examples include starch separated from cereals such as cypress; and starch separated from potatoes such as potatoes, horse mackerel, and mackerel. These may be used alone or in combination.

Next, as a method of granulating this starch to obtain granular starch, the starch may be used as it is, or preferably, water may be uniformly added to the starch until the water content is 7-'Jθ% (hereinafter referred to as humidification), preferably A 10 to 40% wet powder or a wet kneaded body is prepared, and this is subjected to ordinary granulation means to obtain granular starch having an outer diameter of 1 to 15 m, preferably 3 to 8 w1. The above-mentioned humidification and granulation may be performed sequentially, or may be performed all at once in one step.

As the above granulation means, any means may be used,
For example, a rotating cylinder-type transfer granulation method in which wet starch is supplied to an inclined rotating cylinder and is aggregated into granulated starch as it moves in the cylinder: the starch is fluidized with hot air or dry air, Fluidized bed granulation method, in which water or a binder (such as a dilute starch paste solution) is sprayed onto this to perform agglomeration granulation; Depending on the crushing mechanism, a stirring granulation method using a Kuspapu mill, Henschel or Eirich type; starch aggregates are crushed by a rotating knife and discharged from a screen. Alternatively, a rotating knife type in which starch aggregates are broken up by a high-speed rotating knife and discharged from a cylindrical screen, or rotation in which a prismatic or cylindrical rotating bar is used to loosen starch aggregates and discharge them from a screen. Bar format crushing and granulation method: Starch is put into a mold on the surface of a rotating roll and compressed to make briquettes, or a mortar is filled with a medium amount of starch.

A compression molding method in which the tablets are compressed between a lower punch and an upper punch to form a tablet; and a screw method in which the material is transported by a starch screw with low moisture content and extruded from a cylindrical die.
Or, put low-moisture starch between the rotary die and the p-ru,
Examples include a rotating die type extrusion method in which the starch is extruded from a die using rolls, and a rotating blade type extrusion method in which low-moisture starch is put into a die and then extruded from the die using a rotating paddle.

Furthermore, as described above, it is preferable to add a binder (for example, a glue obtained by heating starch with water or warm water while stirring) during humidification and/or granulation, since this makes the granular starch less likely to break. In this case, it is preferable to add the glue in an amount of 10 to 100% by weight, particularly 30 to 80% by weight, based on the starch.

The starch obtained in this way may be used as it is, but if there is a lot of surface moisture, it tends to dry up and stick to the inner wall of the device or each other during the first superheated steam treatment, so the moisture content is 6 to 25%. , preferably 10 to 20%.

Drying methods include ventilation drying, hot air drying, vacuum drying, etc.
Any means may be mentioned. Granular starch obtained by drying only one surface by hot air drying or ventilation drying is
In superheated steam treatment.

Since it is difficult for Vζ to adhere to each other and retains an appropriate amount of moisture necessary for α-ization, the superheated steam treatment reduces α.
It is possible to obtain processing starch with a high degree of chemical conversion.

Next, the granular starch is heat-treated in the presence of superheated steam to obtain a starch for processing.

The present invention is characterized in that granular starch is heat-treated with superheated steam rather than powder, and this is extremely important. Starch for processing of appropriate and uniform quality may be lost due to starch being left behind near the raw material inlet or raw material discharge part, or due to stagnation and burnt browning, and some of the burnt raw material getting mixed into the product. The disadvantage is that it is often difficult to obtain.

In addition, powdered starch retains water less easily than granular starch, so water is added to powdered starch to increase gelatinization.
Even if it is introduced into a superheated steam treatment device, there are disadvantages in that the water quickly disappears within the device and it is difficult to obtain the desired degree of gelatinization.

On the other hand, when starch is granulated and treated with superheated steam as granular starch, the starch may adhere to the inside of the processing equipment or
Furthermore, the above-mentioned inconvenience does not occur because it does not stay in a specific location. Moreover, by granulating it, it becomes easier to retain moisture inside, so the degree of gelatinization of the starch for processing can be easily increased.

In the present invention, it is extremely important to use superheated steam as a heating medium for the 5-granular starch, and other heating media such as heated air or saturated steam are not preferred because they cannot achieve the purpose of the present invention.

In other words, in the case of heated air, the thermal conductivity is poor, so it takes a long time to raise the temperature to the inside of the granular starch. When heated, it tends to burn, and the granular starch tends to brown due to oxidation in a short period of time.

In addition, in the case of saturated steam, when granular starch comes into contact with saturated steam, the steam condenses and adheres to the surface of the granular starch, and the starch on the surface gelatinizes, so that the granular starch adheres and bonds with each other. If it becomes a large lump, adheres to the inner wall surface of the device, or increases moisture locally, α
It becomes difficult to obtain processed starch.

On the other hand, when using superheated steam, it is possible to prevent quality deterioration such as browning and scorching due to oxidation of granular starch, partial excessive water content of starch, gelatinization, clumping of granular starch, uneven agization, etc., while preventing quality deterioration. By increasing the temperature of granular starch over time, it is possible to obtain highly desirable processing starch with a high degree of gelatinization.

Next, the heat treatment conditions for the granular starch vary depending on the physical properties of the starch for processing, such as the size of the grain, the internal moisture content of the grain, the desired degree of gelatinization, etc., and may be at normal pressure, but preferably at a gauge pressure of 0.
．． 5~15 kg/ad1%K 2~9kg/t-d
is preferable, and the temperature is 115°C to 350°C1 [150°C to 350°C].
260°C is preferred. Moreover, the time is preferably 2 seconds to 5 minutes, particularly 5 seconds to 2 minutes. The relationship between warm pressure and heating conditions and time is inversely proportional, and it is preferable to shorten the time when the temperature is high and to lengthen the time when the temperature is low. Pressure treatment is preferable as it has various advantages over normal pressure treatment, such as shorter treatment time. The heating conditions for the superheated steam used in the present invention are as described above, but if the conditions exceed a gauge pressure of 15 and a temperature of 9/-1 of 350°C, a burnt odor will adhere to the starch, and it will cause discoloration (browning) and This is not preferable as it will cause significant burns. Also, on the contrary,
If the temperature is less than 115°C, the physical properties of the product, starch for processing, cannot be sufficiently changed, and if the desired starch for processing is obtained at a temperature of 115 to 350°C, a suitable method that does not have the above disadvantages may be used. Starch for processing is obtained.

The granular starch thus pressurized and heated is gradually or preferably instantaneously released under lower pressure, for example atmospheric pressure, to obtain granular starch for sensitized processing.

Examples of devices for carrying out the above-mentioned superheated steam treatment include JP-B No. 46-34747r "Method and Apparatus for Producing Puffed Foods by Air Stream Heating Method", JP-A No. 55-33622r Continuous Steaming and Heating Apparatus", and JP-A No. 56-26180R Powder Apparatus described in "Heat sterilization method for grains", JP-A-57-826
86r, "Method for heat treatment of granular materials and electrical production", etc.

By adjusting the water content of the granular starch, the pressure, temperature and time of the superheated steam as appropriate, it is possible to obtain processed materials with various degrees of -ization, swelling degree, gel strength, etc., and with a very small number of viable bacteria. It is possible to obtain starch for processing which is excellent for use.

The starch for processing thus obtained is in the form of granules, but if necessary, it may be further classified using a classifier using a sieve or screen (mesh) to make the particle size uniform. Furthermore, depending on the intended use, it may be dried and/or pulverized (pulverized).

[Effects of the present invention]

The advantages of the invention are as follows.

(1) Since the present invention heat-processes starch under low moisture conditions, it is economical as it requires less thermal energy than the drum dryer method.

(2) Since granular starch is heat-treated in a medium-sized container while being in direct contact with a large amount of superheated steam, a large amount of starch can be processed in a short amount of time, and starch granules are less likely to be destroyed.

(3) Since the starch is granulated and treated with superheated steam as granular starch, the starch may adhere to the inside of the processing equipment.
In addition, it is possible to prevent the starch from staying in specific places, and it is possible to prevent the starch from becoming partially charred or colored (browning).

(4) During the superheated steam treatment, it is possible to maintain the water content of the starch to be treated at the level of water required for monoconversion of starch, so the degree of monoconversion can be increased by a fraction of a son.

(5) The degree of a-ization, etc. can be arbitrarily changed by appropriately changing the water content of the granular starch, the pressure, temperature, and time conditions of the superheated steam.

(6) Starch for processing can be obtained in which deterioration in quality, such as starch browning and scorching due to oxidation, partial excess moisture in starch, partial gelatinization, and uneven agization, is prevented as much as possible.

(7) The processed starch obtained by the present invention can be used as a food material itself, and can also be used in various foods, drugs, industrial adhesives, etc. for which conventional starch or its processed starch is known to be used. It can be used in place of the starch (or processing starch) to improve the expected quality of the product.

Namely, the powdered starch for processing obtained by the present invention is as follows.

When dispersed in water, there is almost no lump formation, and it dissolves uniformly and quickly just by gentle stirring, and the stability of the dissolved product is excellent, so it can be used in instant soups, instant soups, cakes, etc.

It is used as a starch material for instant foods such as couscous, and as a thickening agent for sauces and gravy, and is processed under high temperature and high pressure conditions, so it is biologically purified and has a soft texture. So 1 For example, rice crackers such as rice crackers, rice crackers, snack food, food products, Western sweets, bread, etc. 1
It has excellent effects on texture improvement, prevention of deterioration (aging), flavor improvement, and flavor retention immediately after production. Furthermore, when applied to foods that require high viscosity (binding properties) during the processing process (for example, deep-frying process), such as croquettes and batters for frying, it provides excellent moldability. In addition, when used in processed meat products such as ham, sausage, and hamburger steak, and processed seafood products such as kamaboko and chikuwa, it has excellent binding retention effect, gel reinforcement effect, syneresis prevention effect when kept at low temperature, and anti-aging effect during storage. It has effects etc.

When used in heated foods such as retort processed foods, it has a good gel strength retention effect. Further, according to the present invention, processing starches having various degrees of gelatinization and digestibility can be obtained, and among them, starches with a good degree of gelatinization and digestibility are suitable for use as feed for livestock and fish farming, and fishing bait. In addition, finely pulverized products have excellent water retention properties, so they can be suitably used as base materials for cosmetics, pharmaceuticals, and agricultural chemicals, and for single-tablet powder materials. Yet again. For other industrial purposes, it can be used as an adsorption base material and carrier for various fragrances, as an adsorption carrier for enzymes, and as an inner layer filler for soundproofing and moistureproofing materials.

Hereinafter, the present invention will be explained in more detail by showing examples.

Example 1 (Production of processing starch from cornstarch) As raw materials,
Using 10 Kf of cornstarch (10% moisture), heat a 10% by weight aqueous cornstarch solution with stirring, mix 2 with starch paste 6 and knead to obtain a wet kneaded product, which is manufactured by Seikoku Seisakusho. The starch was placed in a basket of a single-type granulator (a perforated plate with a hole diameter of 6 slIl), granulated by extrusion, and then dried in a hot air dryer at 80° C. to obtain granular starch with an average moisture content of 15.0%.

Next, this granular starch is heated using a continuous pressure heating device using an air current heating method (device described in Japanese Patent Publication No. 46-34747).
K was continuously introduced and heat treated under the pressure and heating conditions listed in Table 1 below to obtain granular pregelatinized cornstarch having the appearance and characteristics listed in Table 1.

The digestibility of these enzymes (according to the Sake Rice Research Group's "Unified Analysis Method for Sake Rice") and degree of gelatinization (according to Keiji Kainuma et al., "Starch Science J 28.235 (1981)") are shown in Table 1. That's right.

From the results in Table 1, it can be seen that Category 2 (comparative example) using saturated steam is sticky overall with partial lumps, the degree of gelatinization is low, direct reducing sugar and Baume are slightly low, and digestibility is slightly low. Category 3 (comparative example), which has a low separation point and uses heated air, has an overall light brown color and a considerable burnt odor, but
In category 1 (invention) using superheated steam, the obtained granular pregelatinized cornstarch is entirely smooth and granular.

It is clear that there are no lumps, the color is white, there is no off-flavor, and the degree of gelatinization is very high.Furthermore, good results can be obtained in terms of digestibility, with high Baume and direct reducing sugars.

Example 2 (Production of starch for processing from granular starch with different particle sizes) In the method for producing granulated cornstarch in Example 1 above, the pore diameter of the basket of the granulator was changed to the pore diameter as shown in Table 2. Granulated cornstarch having various particle sizes was obtained in exactly the same manner except for the following steps.

We investigated the relationship between the particle size of granular starch and the characteristics of granular 6-processing starch (formation of cohesive lumps) obtained by heat-treating the granular starch with superheated steam, as shown in Table 2. The results were obtained.

From the results in Table 2, it can be seen that in the case of granular starch with a particle size of 1 square centimeter, there are many bound lumps, but when the particle size is 2 square meters, the number decreases, and when the particle size is 3 square meters or more, they are not found here and there (i.e., granular The starch particle size is 2 cm or more.

It can be seen that a very favorable granulated processing starch is obtained.

Table 2 (Particle size of granular starch and characteristics of superheated steam treated starch) (Note)
10: Many ±: Occasionally found 1: None Example 3 (Production of processing starch from potato starch) The inside of a cylindrical tank is partitioned by a dispersion plate with a large number of air holes perforated upward. A flow chamber and a lower ventilation chamber are formed, dry air is supplied to the lower chamber, and the dry air is blown up from the air hole into the flow chamber to uniformly fluidize the potato starch with the air flow, and to 10% of potato starch
The starch paste obtained by heating the aqueous solution while stirring is diluted with warm water, and the obtained binder is dispersed (sprayed) to perform agglomeration and granulation, and then it is classified to obtain granular starch with a particle size of about 7. Obtained.

Next, the above-mentioned granular starch is placed in a closed cylindrical container filled with superheated steam, and a high-speed stirring method is used in which rotatable blades are rotated at high speed with a small gap around the inner circumference of the cylinder to stir and disperse the raw material. into a heating device with a gauge pressure of 3.0 Yu/c.
d. Pressurized and heated for 60 seconds in the presence of superheated steam at a temperature of 230°C, and after gradually decompressing, the starch was taken out to obtain a non-expanded starch for granulation processing with a degree of gelatinization of 72 degrees.

Example 4 (Production of starch for processing from cornstarch) Add water to cornstarch to obtain a wet powder with a water content of 22%, put this into a screw extrusion granulation system, and rotate the 11 knees in the barrel to make the powder. The wet starch is pressurized and the tip of the die (pore size 4
M) was extruded to obtain granular starch with relatively high density.

As in Example 3 above, this was introduced into a high-speed stirring type heating device filled with superheated steam, and the gauge pressure was 4.0 kg/
After pressurizing and heating at a temperature of 250° C. for 45 seconds, the mixture was gradually decompressed and taken out to obtain granular starch for monomer processing.

Example 5 (Production of starch for processing from mixed starch) 50 parts of corn starch and 50 parts of potato starch were mixed and stirred, 50 parts of water was added and kneaded, and the starch was mixed with a roll rotating in contact with a cylindrical screen. The product was extruded and granulated using a roll-type extrusion granulator (also referred to as a beret), dried through ventilation, and then classified to obtain granules with a particle size of 5.

Next, this granular starch is continuously introduced into a continuous pressure heating device using an air flow heating method (equipment described in Japanese Patent Publication No. 46-34747), and the gauge pressures s, oy, 'y, and the temperature 2 are maintained.
After pressurizing and heating for 7 times in the presence of superheated steam at 50°C, the starch was instantaneously and continuously discharged to atmospheric pressure to obtain processing starch with a high degree of gelatinization.

Example 6 (Manufacture of starch for processing from tapioca starch) Fill a white medium tonne with a certain volume of tapioca starch (moisture 13%) and compression mold it between the lower and upper punches to give a diameter of 6u. Tablet-shaped tapioca starch with a thickness of 3u was obtained.

Next, this was introduced one by one into a continuous pressure heating device using the air flow heating method as in Example 5 above, and heated with superheated steam at a gauge pressure of 5.0 at a temperature of 9/i and a temperature of 250°C. After pressurizing and heating for 7 seconds in the presence of the starch, it was continuously released under atmospheric pressure to obtain granular pregelatinized tapioca starch, which was crushed by a conventional method to obtain powdered starch for processing. .

Claims (5)

[Claims] (1) A method for producing starch for processing, which comprises granulating starch into granular starch and heat-treating it in the presence of superheated steam. (2) A method for producing starch for processing, which comprises granulating starch into granular starch in the presence of a binder and heat-treating the starch in the presence of superheated steam. (3) The method for producing starch for processing according to claim 2, wherein the binder is starch paste. (4) A method for producing starch for processing, which comprises granulating starch into granular starch, drying it, and then heat-treating it in the presence of superheated steam. (5) Starch is barley starch, corn starch, potato starch,
The method for producing a processing starch according to any one of claims 1 to 4, wherein the starch is one or more selected from the group consisting of sweet potato starch, tapioca, sorghum starch, and millet starch.