JP2006180868A - Method for producing chlorella fermented food - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a chlorella fermented food decreased in flavor and smell peculiar to alga while suppressing production of pheophorbide. <P>SOLUTION: This method for producing the chlorella fermented food comprises using chlorella containing ≤18 mg% of free pheophorbide and having coliform group number negative and general viable cell number of ≤8,000 cfu/mL, and fermenting the chlorella with baker's yeast. The chlorella is obtained, for instance, by washing chlorella before fermentation using water at 0-10°C, or subjecting to heat sterilization treatment. The baker's yeast is mixed with the chlorella preferably at 0.1-15 wt.% ratio. Fermentation treatment is performed preferably in the presence of glucose and lactic bacterium. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a chlorella fermented food.

Chlorella is a food rich in protein, chlorophyll, dietary fiber, various vitamins and minerals, and has been conventionally eaten as a substitute for green-yellow vegetables and as a dietary supplement.
However, chlorella has a unique algal odor and is difficult to taste. In addition, when chlorella is decomposed, pheophorbide, which is a causative substance of photosensitivity, is produced by an enzyme called chlorophyllase contained in chlorophyll.

On the other hand, conventionally, a chlorella enzyme production method (Patent Documents 1 and 2) in which chlorella and an enzyme stock solution containing yeast are mixed and fermented under predetermined conditions, and fermentation of vegetables, wild grasses and fruits containing chlorella and yeast. A chlorella production method (Patent Document 3) is proposed in which a stock solution and a mixture of white birch are mixed and fermented under predetermined conditions.
JP-A-9-322768 JP 2002-218952 A JP 2003-88339 A

  However, the inventions described in the above Patent Documents 1 to 3 relate to a method for processing chlorella into an easily absorbable state, and are intended to improve the chlorella to be easily consumed as food. is not. In particular, in the inventions described in Patent Documents 1 and 2, since the enzyme stock solution contains yeast, actinomycetes, filamentous fungi, lactic acid bacteria, and the like, a complicated fermentation flavor is produced by fermentation. . In addition, in the invention described in Patent Document 3, in addition to an enzyme stock solution containing yeast, actinomycetes, filamentous fungi, lactic acid bacteria, etc., a unique flavor due to fermented products such as vegetables is added. Therefore, in either case, the ease of taking chlorella is insufficient.

  Further, in the inventions described in Patent Documents 1 to 3, no consideration is given to the fact that chlorella is a material that easily generates pheophorbite. Chlorophylase that produces pheophorbide is an enzyme contained not only in chlorella but also in vegetables and the like, and since the enzyme activity is increased by alcohol, it is originally a chlorophyllase contained in the entire system. Careful attention must be paid to various points such as the amount of phyllase, the composition of the enzyme stock mixed with chlorella, and factors affecting the enzyme activity of chlorophyllase (for example, alcohol produced during fermentation).

  Then, the objective of this invention is providing the method for manufacturing the chlorella fermented food which reduced generation | occurrence | production flavor and smell peculiar to algae, suppressing generation | occurrence | production of pheophorbite.

In order to achieve the above object, the present invention provides:
(1) fermenting the chlorella with baker's yeast using a chlorella having a free pheophorbide content of 18 mg% or less and a general viable cell count of 8000 cfu / mL, which is negative for the number of coliforms. A method for producing a chlorella fermented food,
(2) The method for producing a chlorella fermented food according to (1) above, wherein the chlorella before fermentation with baker's yeast is washed with water at 0 to 10 ° C.
(3) A method for producing a chlorella fermented food, characterized by fermenting chlorella subjected to heat sterilization with baker's yeast,
(4) The method for producing a chlorella fermented food according to any one of (1) to (3), further comprising fermenting in the presence of a saccharide.
(5) The method for producing a chlorella fermented food according to any one of (1) to (4), further comprising fermenting in the presence of lactic acid bacteria,
(6) The chlorella fermentation according to any one of (1) to (5), wherein a blending amount of the baker's yeast is 0.1 to 15% by weight based on a blending amount of the chlorella. Food manufacturing methods,
I will provide a.

  In the present invention, the content (mg%) of free pheophorbite is “Food Hygiene Inspection Guidelines, Physical Chemistry”, Japan Food Sanitation Association, 289-290 (1991), “(a) Quantitative Determination of Existing Pheophorbide”. It measures according to the method of description. A specific measurement method is as follows. After extracting 100 mg of chlorella with 85% acetone and adding ether to separate, the ether layer is taken out. The ether layer is extracted with 17% hydrochloric acid, a saturated sodium sulfate solution is added to the resulting hydrochloric acid solution, and the mixture is extracted with ether. The absorbance of the ether layer thus obtained was measured at 667 nm, and the amount of chlorophyll degradation was calculated from the absorbance of the standard pheophorbite a, and this was calculated as the content of free pheophorbite (existing pheophorbide amount; unit mg %).

  In the present invention, the number of general viable bacteria (cfu / mL) is measured by an official method using a standard agar medium (“Food Hygiene Inspection Guidelines for Microorganisms”, Japan Food Sanitation Association, 1990). A specific measurement method is as follows. 10 g of chlorella is added to 90 mL of sterile water and the resulting suspension is used as the test solution. Next, this test solution is appropriately diluted and cultured in a standard agar medium at 35 ° C. for 24-48 hours, and then the number of colonies in the petri dish is counted.

  In the present invention, whether the number of coliforms is negative or positive is determined by an official method using BGLB medium ("Food Hygiene Inspection Guidelines for Microorganisms", Japan Food Sanitation Association, 1990). A specific determination method is as follows. 10 g of chlorella is added to 90 mL of sterile water and the resulting suspension is used as the test solution. Next, 1 mL of the obtained test solution is added to the BLGB medium housed in the Durham tube and cultured at 35 ° C. for 24 to 48 hours, and then generation of gas in the Durham tube is confirmed. Here, only when the generation of gas is not recognized, the number of coliforms is negative.

According to the method for producing a chlorella fermented food of the present invention, by fermenting chlorella with baker's yeast, the flavor and smell peculiar to algae can be reduced, and a chlorella fermented food that is easy to ingest can be provided.
In addition, according to the method for producing a chlorella fermented food of the present invention, a predetermined washing treatment for reducing the content of free pheophorbide in advance, or a heat sterilization treatment for deactivating chlorophyllase, on chlorella In addition, since fermentation using baker's yeast suppresses the production of alcohol associated with fermentation as much as possible, activation of chlorophyllase and generation of pheophorbite associated with fermentation treatment are suppressed. Can be suppressed.

The first chlorella fermented food production method according to the present invention is such that the free pheophorbite content is 18 mg% or less, the general viable cell count is 8000 cfu / mL or less, and the coliform group count is negative. It is characterized by fermenting this chlorella with baker's yeast using the adjusted chlorella.
Moreover, the manufacturing method of the 2nd chlorella fermented foodstuff which concerns on this invention is characterized by fermenting the chlorella which heat-sterilized processing was performed with baker's yeast.

The raw material chlorella for fermentation with baker's yeast is not particularly limited, and examples thereof include various chlorellas such as those cultured in a culture pond using sunlight and those cultured by tank culture.
Further, the raw material chlorella may be one in which the content of various nutrients is increased by setting the culture environment or the like. Examples of the nutrient include iron, zinc, DHA (docosahexaenoic acid), and the like.

The raw material chlorella may be powdered by drying and pulverizing or spray-drying the chlorella subjected to the above-described washing treatment.
In the first method for producing a chlorella fermented food, in order to adjust the content of free pheophorbite of chlorella to 18 mg% or less, for example, in each step of chlorella cultivation, harvesting, washing and concentration, chlorella cells are It is preferable not to kill as much as possible. When chlorella cells die, chlorophyllase, a pheophorbite-producing enzyme, elutes, leading to an increase in the content of free pheophorbite, contamination of free chlorophyllase into the raw material chlorella, There is a risk of increasing the content of pheophorbite (in chlorella fermented food) after the fermentation treatment.

  As a specific method for adjusting the content of free pheophorbide of chlorella to 18 mg% or less, reducing the number of general viable bacteria to 8000 cfu / mL or less, and adjusting the number of coliforms to be negative For example, a method of washing the cultured and harvested raw chlorella with water at 0 to 10 ° C. (preferably with water at about 4 ° C.) can be mentioned. The cleaning process is not limited to this, and for example, a centrifuge can be used.

  From the viewpoint of reducing the number of general viable bacteria and adjusting the number of coliforms to be negative, the chlorella washing treatment is more preferably at a temperature of 0 to 10 ° C. and has a bactericidal action. It is preferable to use the water that it has. Examples of water having a bactericidal action include electrolyzed water (so-called strong acidic water, acidic water, alkaline water and strong alkaline water obtained by electrolyzing an aqueous electrolyte solution), a small amount of excited iron ions. Examples include water activated by (so-called π water), ozone water, and water containing a bactericidal agent (for example, hypochlorite).

  The content of free pheophorbite in the raw material chlorella is 18 mg% or less, preferably 10 mg% or less as described above. Note that the content of free pheophorbite is usually increased by subjecting chlorella to fermentation. Therefore, from the viewpoint of suppressing the content of free pheophorbite in the chlorella fermented food, the content of free pheophorbite in the raw material chlorella suspension before the fermentation treatment is set in the above range.

By setting the content of free pheophorbite for chlorella (raw material) before fermentation treatment to the above range, the content of free pheophorbite for chlorella (chlorella fermented food) after fermentation treatment, It can be set to 60 mg% or less.
In relation to the safety of chlorella processed products, according to the former Director General of the Ministry of Health and Welfare, Environmental Health Bureau (May 8, 1981), the content of free pheophorbide in chlorella processed products exceeds 100 mg%, or The total amount of pheophorbite (described later) should not exceed 160 mg%. In recent years, the industry standard values for chlorella processed products are set such that the content of free pheophorbite in the chlorella processed product is 60 mg% or less and the total pheophorbite amount is 80 mg% or less.

Therefore, to improve the safety of the chlorella fermented food of the present invention by pre-treating the chlorella (raw material) before fermentation treatment so that the content of free pheophorbide is in the above range. Can do.
Examples of the index indicating the content of pheophorbite include the total amount of pheophorbite (mg%) together with the content of the above free pheophorbite. The total amount of pheophorbide (mg%) refers to the sum of the content of free pheophorbite and the chlorophyllase activity. Here, the chlorophyllase activity is the amount of pheophorbite (mg%) increased by the above reaction when chlorella is reacted in a buffer solution (for example, phosphate buffer-acetone mixed solution) for 3 hours. Indicates. The total amount of pheophorbite is, for example, obtained by adding a phosphate buffer (pH 8.0) -acetone mixed solution (volume ratio 7: 3) to 100 mg of chlorella and fermenting at 37 ° C. for 3 hours, and then obtaining chlorella It is determined by making the solution weakly acidic with 10% hydrochloric acid and then measuring in the same manner as the method for measuring the content of free pheophorbite.

As described above, the total pheophorbite content of chlorella (chlorella fermented food) after the fermentation treatment is 80 mg% or less as an industry standard value.
As described above, the general viable cell count for the raw material chlorella for fermentation with baker's yeast is 8000 cfu / mL or less, and preferably 3000 cfu / mL or less. If the number of viable bacteria in the chlorella suspension, which is the raw material of the chlorella fermented food, exceeds 8000 cfu / mL, or if the number of coliforms is positive, the chlorella fermented food is not suitable as a food.

In the method for producing the second chlorella fermented food, the heat sterilization treatment of chlorella is not limited to this, and examples thereof include various methods such as blanching treatment using steam. The blanching process is not particularly limited, and examples thereof include various blanching processes such as steam blanching and blanching in hot water.
The conditions for the heat sterilization treatment are not particularly limited. For example, the heat treatment temperature is preferably 90 to 110 ° C., more preferably 95 to 105 ° C., and the heat treatment time is preferably 20 seconds to 5 minutes. More preferably, it is 40 seconds to 2 minutes.

  By subjecting the raw material chlorella before the fermentation treatment to heat sterilization treatment, the chlorophyllase in the chlorella can be killed and activated, and therefore an increase in the content of pheophorbite after the fermentation treatment can be prevented. In addition, by performing heat sterilization treatment, it is possible to kill germs adhering to chlorella, and to reduce the number of viable bacteria and coliform bacteria to the above-mentioned range in the stage before performing the fermentation treatment. Can do.

  In the first and second chlorella fermented food production methods, when the raw material chlorella is used as a powder, the particle size of the chlorella powder is not particularly limited. The average particle size of the secondary particles is usually about 60 μm. When the aggregate is finely pulverized and adjusted so that the average particle size (50% particle size) of the secondary particles is about 3.0 to 10 μm, the time required for fermentation of chlorella can be shortened, As a result, the flavor, aroma and texture of the chlorella fermented food can be further improved. Furthermore, it can suppress more effectively that pheophorbite produces | generates by the chlorophyllase which remains in a chlorella by shortening fermentation time.

The method for finely pulverizing chlorella is not particularly limited, and examples thereof include a method for finely pulverizing using a stone mill and a method for pulverizing using an airflow pulverizer.
Baker's yeast is used for fermentation of chlorella. Thereby, the production | generation of the alcohol accompanying fermentation can be suppressed as much as possible.
The baker's yeast is not particularly limited, and various types of baker's yeast that can be used as an edible yeast can be mentioned.

The compounding quantity of baker's yeast is 0.1-15 weight% with respect to chlorella, Preferably, it is 0.5-10 weight%, More preferably, it is 0.5-5.0 weight%.
The conditions for the fermentation treatment with baker's yeast are not particularly limited. For example, the fermentation temperature is preferably 15 to 45 ° C, more preferably 30 to 40 ° C, and the fermentation time is preferably 1 to 7 hours. More preferably, it is 1.5 to 5 hours.

It is preferable to perform the fermentation process by baker's yeast in a state with oxygen from a viewpoint of suppressing the production | generation of alcohol. Furthermore, from the viewpoint of suppressing the production of alcohol, the water content of chlorella at the time of fermentation treatment is set to the following range, or the mixture containing chlorella and baker's yeast is sufficiently stirred during the fermentation treatment It is preferable.
The water content of chlorella during the fermentation treatment (that is, the ratio of the water content to the total amount of chlorella containing water) is preferably 20 to 70% by weight, more preferably 30 to 55% by weight. When the water content is set in the above range, sufficient oxygen is supplied to the yeast, and the production of alcohol can be suppressed.

In order to set the water content of the chlorella within the above range, the chlorella used as a raw material for the fermentation treatment may be prepared as a suspension dispersed in water. Moreover, about stirring of the chlorella during a fermentation process, it does not specifically limit, What is necessary is just to stir according to a conventional method.
In addition, chlorella used as a fermentation raw material has its chlorophyllase activity reduced by a predetermined washing process, or its chlorophyllase content has been sufficiently reduced, or has been subjected to a heat sterilization process. Therefore, it is not always necessary to ferment in the presence of oxygen. For example, it can be fermented by liquid culture using baker's yeast.

  In the above liquid culture, the harvested and washed chlorella is prepared as a suspension having a solid content concentration of 5 to 25% by weight, preferably 10 to 15% by weight. (If necessary, repeat). What is necessary is just to mix | blend the fermentation process by subsequent baker's yeast in the range of the compounding quantity of baker's yeast with respect to the chlorella solid content in the said suspension, and to ferment.

When chlorella is fermented with baker's yeast, not only the flavor unique to chlorella is improved and the odor is reduced, but also nutrient components such as proteins, carbohydrates and lipids are more easily digested and absorbed. Moreover, as is clear from the results of Examples described later, the content ratio of various micronutrients such as minerals increases.
Chlorella fermentation is preferably performed in the presence of saccharides, more preferably in the presence of lactic acid bacteria.

Although it does not specifically limit as saccharides, For example, glucose, a trehalose, raffinose, fructose, sucrose, starch, a starch degradation product, molasses, waste sugar etc. are mentioned. These saccharides may be used alone or in combination of two or more.
By fermenting chlorella in the presence of the above saccharides, the fermentation proceeds smoothly and the time required for the fermentation treatment can be shortened.

Among the above-mentioned examples, the saccharide is preferably glucose or a combination of glucose and trehalose from the viewpoint of promoting the fermentation effect of chlorella and adjusting the flavor of the chlorella fermented food. In addition, trehalose has a strong water holding power, and can mix water with chlorella evenly by mixing with chlorella.
The blending amount of saccharides is not particularly limited because it varies depending on the types and properties of saccharides such as monosaccharides, disaccharides, oligosaccharides and polysaccharides. For example, the blending amount of glucose is preferably 0. It is 5 to 2.0% by weight, and more preferably about 1% by weight. The amount of trehalose is preferably 0.1 to 5% by weight, more preferably 0.5 to 2.0% by weight, based on chlorella.

The lactic acid bacterium is not particularly limited except that it is an edible lactic acid bacterium, and examples thereof include Bifidobacterium, Enterococcus, and Lactobacillus.
Although the compounding quantity of lactic acid bacteria is not specifically limited, For example, Preferably it is 0.05 to 5.0 weight% with respect to chlorella, More preferably, it is 0.2 to 3.0 weight%.

The chlorella fermented food can be formulated into various known dosage forms such as powders, granules, tablets, etc., depending on the purpose and application.
In addition, the chlorella fermented food obtained by the production method of the present invention may be formulated as a chlorella fermented food alone or in combination with an excipient depending on the dosage form, purpose and application. The blending ratio of the chlorella fermented food with respect to the excipient can be appropriately selected from the range of 0.1 to 99% by weight.

Next, although this invention is demonstrated based on an Example and a comparative example, this invention is not limited by the following Example.
<Test Example 1>
Example 1
The chlorella cultured in a natural culture pond using sunlight was blanched with steam at 100 ° C. for 1 minute, subjected to heat sterilization, and then spray-dried. Mixing the chlorella powder thus obtained with 0.05% by weight of baker's yeast (dry yeast) and water, and mixing and kneading the mixture, the water content was adjusted to 40% by weight. Obtained.

Next, the said mixture was fermented by leaving still at 35 degreeC for 3 hours. Furthermore, the chlorella fermented material was obtained by heating and drying at 110 degreeC and adjusting a moisture content to 5 weight% or less.
Examples 2-8
A chlorella fermented product was obtained in the same manner as in Example 1 except that the blending ratio of baker's yeast relative to the blending amount of chlorella powder was changed to the ratio shown in Table 1 below.

Comparative Example 1
A chlorella cultured in a natural culture pond using sunlight was sterilized by heating with steam at 100 ° C. for 1 minute, and then spray-dried. After kneading the chlorella powder thus obtained and water, the resulting mixture was heated and dried at 110 ° C. to adjust the water content of the mixture to 5% by weight or less.

Evaluation of taste and odor The chlorella fermented product obtained in Examples 1 to 8 and the dried mixture obtained in Comparative Example 1 were actually sampled by 5 subjects (2 adult men and 3 adult women). We asked them to evaluate the flavor and odor and averaged the evaluations. The evaluation criteria are as follows.
-Strong flavor: I felt strongly the flavor of algae or yeast and it was difficult to eat.
Yes: Algae or yeast flavor was felt, but there was no inconvenience in eating.
Weak: A slight algae or yeast flavor was felt.
Weak: I felt a slight algae or yeast flavor.
None: Almost no algae or yeast flavor was felt.

・ Strong smell: I felt a strong smell of algae or yeast and it was difficult to eat.
Yes: Algae odor or yeast odor was felt, but there was no inconvenience in eating.
Slight: Algae odor or yeast odor was slightly felt.
Slight: Algal odor or yeast odor was felt slightly.
None: Algal odor or yeast odor was hardly felt.

  The evaluation results are shown in Table 1 below.

In Table 1, the blending amount of baker's yeast indicates a weight ratio (% by weight) with respect to the blending amount of chlorella powder.
As is clear from the results shown in Table 1, by fermenting chlorella with baker's yeast, the flavor and smell of algae were suppressed, and a chlorella fermented product that was easy to ingest could be obtained. In addition, chlorella can be fermented in a relatively short time of 3 hours, and in addition, the production of alcohol associated with the fermentation can be suppressed, so that the production of pheophorbite can also be suppressed.

By setting the blending amount of baker's yeast in the range of 0.1 to 15% by weight with respect to the blending amount of chlorella, the flavor and smell of both algae and yeast could be reduced. Moreover, from the result shown in Table 1, it turned out that it is preferable that the compounding quantity of baker's yeast is 0.5 to 5 weight% especially in the said range.
On the other hand, in the comparative example 1 which has not performed the fermentation process by baker's yeast, there existed a malfunction that the flavor and smell of algae were strong and it was hard to eat.

<Test Example 2>
Example 9
The chlorella cultured in a natural culture pond using sunlight was blanched with steam at 100 ° C. for 1 minute, subjected to heat sterilization, and then spray-dried. By mixing 3.0% by weight of baker's yeast (dry yeast) and 1.0% by weight of trehalose with water and mixing and kneading the chlorella powder thus obtained, the water content is 40%. A mixture adjusted to% was obtained.

Next, the said mixture was fermented by leaving still at 35 degreeC for 3 hours. Furthermore, the chlorella fermented material was obtained by heating and drying at 110 degreeC and adjusting a moisture content to 5 weight% or less.
Example 10
A chlorella fermented product was obtained in the same manner as in Example 9 except that glucose was added instead of trehalose, and the fermentation time was changed from 3 hours to 2 hours. The blending amount of glucose was adjusted to 1.0% by weight with respect to the blending amount of chlorella powder.

Example 11
A chlorella fermented product was obtained in the same manner as in Example 9 except that glucose was added together with trehalose, and the fermentation time was changed from 3 hours to 2 hours. The blending amounts of trehalose and glucose were adjusted to 1.0% by weight with respect to the blending amount of chlorella powder, respectively.

Comparative Example 2
A chlorella fermented product was obtained in the same manner as in Example 9 except that beer yeast was blended in place of baker's yeast and fermented using this beer yeast.
Evaluation of taste and odor The taste and odor of the chlorella fermented products obtained in Examples 9 to 11 and Comparative Example 2 were evaluated by the same evaluation method and evaluation criteria as described above.

Evaluation of pheophorbite content For the chlorella fermented product obtained in Example 1, Examples 9 to 11 and Comparative Example 2, and the dried mixture obtained in Comparative Example 1, respectively, the total amount of pheophorbite (Mg%) was measured. The method for measuring the total amount of pheophorbite is as described above.
The above evaluation results and measurement results are shown in Table 2 below.

In Table 2, the amounts of baker's yeast, trehalose, and glucose indicate the weight ratio (% by weight) with respect to the amount of chlorella powder. Further, the content (mg%) of pheophorbite indicates the content (mg) per 100 g of the chlorella fermented product. In Comparative Example 2, beer yeast was used instead of baker's yeast (* 1).
In Examples 9 to 11 in which trehalose and / or glucose were blended during the fermentation treatment, fermentation by baker's yeast proceeded smoothly, and in any Example, the flavor and smell of algae could be reduced. . In Comparative Example 2, since it was fermented with brewer's yeast, the flavor and smell of algae tended to be alleviated, although the flavor was different from the example fermented with baker's yeast. .

  In particular, in Examples 10 and 11 in which glucose was blended, although the fermentation time was shortened from 3 hours to 2 hours, the effects of improving the algae flavor and odor could be sufficiently exhibited. In Examples 9 and 10 containing trehalose, not only the flavor and odor of the fermented chlorella were improved, but also moisturizing properties could be imparted to the fermented chlorella, and a fermented product with a moist feel was obtained. I was able to. For this reason, the processability at the time of processing a chlorella fermented material into a tablet etc. was favorable.

With regard to the content of pheophorbite, even when the blanching treatment is performed, chlorophyllase in chlorella cannot be completely removed. Therefore, in Examples 1, 9, 10 and 11, accompanying the fermentation treatment, The pheophorbite content increased slightly. However, the increase was very small.
On the other hand, when alcohol was produced by fermentation as in Comparative Example 2, the increase in the content of pheophorbite accompanying the fermentation treatment was significant.

<Test Example 3>
Example 12
A chlorella cultured in a natural pond using sunlight was blanched with steam at 100 ° C. for 1 minute, subjected to a heat sterilization treatment, pulverized and spray-dried. To the chlorella powder thus obtained, 3.0% by weight of baker's yeast (dry yeast), 1.0% by weight of raffinose and 1.0% by weight of glucose and water are mixed and kneaded. Thus, a mixture in which the water content was adjusted to 40% by weight was obtained.

Next, the said mixture was fermented by leaving still at 35 degreeC for 3 hours. Furthermore, the chlorella fermented material was obtained by heating and drying at 110 degreeC and adjusting a moisture content to 5 weight% or less.
The nutritional component of the fermented chlorella product of Example 12 and the mixture obtained in Comparative Example 1 was analyzed. The analysis results are shown in Table 3.

As is clear from the analysis results shown in Table 3, it was found that the fermented chlorella product had an increased content of minerals such as magnesium as compared to the chlorella that had just undergone the blanching treatment.
<Test Example 4>
Example 13
The chlorella cultured in a natural culture pond using sunlight was blanched with steam at 100 ° C. for 1 minute, subjected to heat sterilization, and then spray-dried. Furthermore, the chlorella powder thus obtained was finely pulverized with an airflow pulverizer so that the particle size thereof was adjusted to about 3.0 to 10 μm.

  Next, a chlorella fermented product was obtained in the same manner as in Example 11 except that the pulverized chlorella powder thus obtained was used. That is, with respect to the finely pulverized chlorella powder, baker's yeast was blended at a ratio of 3.0% by weight, trehalose at 1.0% by weight, and glucose at 1.0% by weight, and mixed and kneaded. As a result, a mixture having a water content adjusted to 40% by weight was obtained. Subsequently, the said mixture was fermented by leaving still at 35 degreeC for 3 hours. Furthermore, the chlorella fermented material was obtained by heating and drying at 110 degreeC and adjusting a moisture content to 5 weight% or less.

When the fermented product thus obtained was compared with the chlorella fermented product obtained in Example 11, Example 13 using chlorella that had been previously pulverized in spite of the same fermentation conditions. According to this, compared with Example 11, the flavor and smell of algae in the chlorella fermented product could be further improved and reduced.
<Test Example 5>
Example 14
The chlorella cultured in a natural culture pond using sunlight was blanched with steam at 100 ° C. for 1 minute, subjected to heat sterilization, and then spray-dried. To the chlorella powder thus obtained, 3.0% by weight of baker's yeast (dry yeast), 1.0% by weight of glucose and 1.0% by weight of lactic acid bacteria (Enterococcus faecium FA-5) and water were blended. By mixing and kneading, a mixture in which the water content was adjusted to 40% by weight was obtained.

Next, the said mixture was fermented by leaving still at 35 degreeC for 3 hours. Furthermore, the chlorella fermented material was obtained by heating and drying at 110 degreeC and adjusting a moisture content to 5 weight% or less.
In the chlorella fermented product thus obtained, the flavor and smell of algae were both sufficiently reduced and improved. Further, the content of pheophorbite was 57 mg%, which could be kept low.

<Test Example 6>
Example 15
Chlorella cultured in a natural culture pond using sunlight was harvested, washed and concentrated to adjust the solid content to 10% by weight. The suspension thus obtained was blanched for 1 minute with steam at 100 ° C. and subjected to heat sterilization. Furthermore, a chlorella powder was obtained by spray drying a part of the suspension after the blanching treatment. The pheophorbite content of this chlorella powder was 35.27 mg%.

  Next, the above-mentioned suspension after the blanching treatment is 3.0% by weight for baker's yeast, 1.0% by weight for glucose and 1.0% for lactic acid bacteria, based on the chlorella solid content in the suspension. Each was mixed so that it might become weight%, and it fermented by lightly stirring at 35 degreeC for 3 hours (liquid fermentation). Further, the fermented suspension was again blanched with 100 ° C. steam for 1 minute, subjected to heat sterilization, and then powdered by spray drying. The pheophorbite content of the chlorella fermented powder thus obtained was 39.42 mg%. Moreover, as for the said chlorella fermented material, both the flavor and smell of algae were fully reduced and improved.

  In Example 15, the content of pheophorbite in the raw material chlorella (before fermentation treatment) exceeds 18 mg%. However, since chlorophyllase has been inactivated by heat sterilization, the content of chlorophyllase is not significantly increased even if fermentation is performed thereafter, and chlorella fermentation About content of chlorophyllase in foodstuff, it was able to be set as the value (39.42 mg%) far less than 60 mg%.

Protein Digestion Test Next, the protein digestibility was compared using the chlorella fermented product obtained in Example 15 and the unfermented product of Comparative Example 1.
The test was conducted using Wistar rats (male, 6 mice, 2 groups in total) that were 4 weeks old at the start of preliminary breeding, and the following preliminary breeding period, first period, second period and third period (each 7 days).

  In the pre-feeding period, each group of rats was fed a solid feed (product number “CE-2”, manufactured by CLEA Japan, Inc.). In the first period and the third period, each group of rats was fed a “protein-free feed” having the composition shown in Table 4 below. In the second period, one group (Group A) is fed with “unfermented chlorella feed” having the composition shown in Table 4 below, and the other group (Group B) is fed with Table 4 below. The “fermented chlorella feed” having the composition shown in FIG.

  The composition of the protein-free feed, the fermented chlorella feed and the unfermented chlorella feed is as follows.

In Table 4, Philis-Hart mixture IV was used as the inorganic salt. Also, the vitamin mixture is vitamin A 50000 IU, vitamin B ₁ 20 mg, nicotinamide 200 mg, folic acid 10 mg, vitamin B ₁₂ 20 μg, vitamin E 20 mg, vitamin D ₂ 4000 IU, vitamin B ₂ 30 mg, vitamin B ₆ 80 mg, calcium pantothenate 200 mg, 750 mg of vitamin C, 4 mg of vitamin K, 10 g of choline chloride and 1.0 g of inositol were used to add flour to a total amount of 100 g.

Subsequently, feces of the latter half 3 days during each breeding period were collected, and the protein mass was measured by the micro Kjeldahl method. Further, the digestibility (%) of the protein was calculated by simultaneously measuring the feed intake and the protein mass (see “Nutrition and Food”, Vol. 30, pp. 93-98 (1977)).
The above results are shown in Table 5.

As is clear from the analysis results shown in Table 5, there was a significant difference in protein digestibility between the rats fed the fermented chlorella feed and the rats fed the unfermented chlorella feed. As a result, the result that protein digestibility was improved was obtained.
Content measurement of β-glucan and γ-aminobutyric acid Furthermore, using the chlorella fermented product obtained in Example 15 and the unfermented product of Comparative Example 1, the content of β-glucan and γ-aminobutyric acid was determined. Compared.

-Measuring method of content of β-glucan A phosphate buffer solution (pH 6.0) was added to each sample collected from the chlorella fermented product of Example 15 and the unfermented product of Comparative Example 1, and suspended. After that, the sample was digested by adding thermostable amylase and allowing to stand. Next, alkali was added to adjust the pH to 7.5, and then protease was added to digest the sample. Further, an acid was added to adjust the pH to 4.3, and amyloglucosidase was added for digestion. 95% ethanol was added to the digested product thus obtained, and the precipitate was filtered off. Subsequently, the filtered precipitate was hydrolyzed with sulfuric acid, neutralized, and the glucose content was measured. In addition, the β-glucan content (mg%) was determined by the following formula using the measured glucose content.

β-glucan content (mg%) = glucose content (g / 100 g) × 0.9
Method for measuring content of γ-aminobutyric acid Samples collected from the chlorella fermented product of Example 15 and the unfermented product of Comparative Example 1 were placed in a container, and after adding 20% hydrochloric acid, Was degassed and sealed. Thus, after hydrolyzing the sample, the content (mg%) of γ-aminobutyric acid in the sample was determined by measuring with an amino acid automatic analyzer.

  The results are shown in Table 6.

  As shown in Table 6, it was recognized that the content of β-glucan and γ-aminobutyric acid can be remarkably increased by performing the fermentation treatment. That is, through fermentation treatment, not only can the flavor and odor peculiar to chlorella be improved, but also the effect of improving the protein digestibility and increasing the content of physiological functional components such as β-glucan and γ-aminobutyric acid can be obtained. It was found that it can be changed to a more preferable food.

<Test Example 7>
Example 16
Chlorella was cultured by adding iron to a natural culture pond using sunlight. The iron content of the obtained chlorella was 300 mg% or more. In addition, the iron content of the chlorella cultured in the natural culture site using sunlight is usually 80 to 200 mg%. The above chlorella having an iron content of 300 mg% or more was harvested, washed and concentrated to adjust the solid content in the suspension to 10% by weight.

  Next, the suspension was blanched with steam at 100 ° C. for 1 minute. The solid content of the suspension thus obtained was 3.0% by weight of baker's yeast and 1.0% by weight of lactic acid bacteria. And fermented by gently stirring at 35 ° C. for 3 hours. After fermentation, the suspension was sterilized by heating with 100 ° C. steam for 1 minute, and then chlorella powder was obtained by spray drying.

The chlorella powder thus obtained had an iron content of 321.1 mg%, and the algae-specific flavor and odor were improved. In addition, the above chlorella powder had a pheophorbite content of 42.29 mg%, and the increase in pheophorbite accompanying the fermentation treatment was extremely low.
Example 17
Chlorella was cultured by adding iron and zinc to a natural culture pond using sunlight. The iron content of the obtained chlorella was 300 mg% or more, and the zinc content was 200 mg% or more. In addition, the zinc content of the chlorella cultured in the natural culture place using sunlight is 2-4 mg% normally. Chlorella having an iron content of 300 mg% or more and a zinc content of 200 mg% or more was harvested, washed and concentrated to adjust the solid content in the suspension to 10% by weight.

Next, a chlorella powder was obtained by blanching treatment, fermentation, heat sterilization, and spray drying in the same manner as in Example 16 except that the above suspension was used.
The thus-obtained chlorella powder had an iron content of 334.5 mg% and a zinc content of 287.7 mg%, and the algae-specific flavor and odor were improved. In addition, the above chlorella powder had a pheophorbite content of 42.29 mg%, and the increase in pheophorbite accompanying the fermentation treatment was extremely low.

<Test Example 8>
Comparative Example 3
Chlorella cultured in a natural pond using sunlight is harvested and repeatedly washed and concentrated with water at 4 ° C under cooling (4 ° C), so that the free pheophorbite value is 0 mg%. A suspension (solid content 10% by weight) was obtained.

Next, the suspension was subjected to a blanching treatment with steam at 100 ° C. for 1 minute, heat-sterilized, and then spray-dried to obtain a chlorella powder.
Example 18
The chlorella suspension obtained in the same manner as in Comparative Example 3 and having a free pheophorbite value of 0 mg% was sterilized by heating by blanching with steam at 100 ° C. for 1 minute. Next, baker's yeast (dry yeast) 3.0% by weight, glucose 1.0% by weight, lactic acid bacteria (Bifidobacterium longum BB536) 1.0% by weight and water based on the solid content of the chlorella suspension, It fermented by leaving still at 35 degreeC for 3 hours. The fermentation solution thus obtained was sterilized by heating with 100 ° C. steam for 1 minute, and then spray-dried to obtain a powder of chlorella fermented product.

Example 19
The same as Example 18 except that a chlorella suspension having a free pheophorbite value of 0 mg% obtained in the same manner as in Comparative Example 3 was used, and this suspension was not subjected to blanching treatment. Thus, a powder of chlorella fermented product was obtained by blending baker's yeast, glucose, lactic acid bacteria and water, fermentation, heat sterilization and spray drying.

Example 20
Chlorella cultured in a natural culture pond using sunlight is harvested and repeatedly washed and concentrated with water at 4 ° C under cooling (4 ° C), so that the chlorella suspension has a solid content of 10% by weight. A turbid liquid was obtained. In addition, by setting the frequency | count of washing | cleaning less than the comparative example 3, the free pheophorbite value of the chlorella after washing | cleaning was 4 mg%.

Using the suspension obtained in this manner, the suspension was not subjected to the blanching treatment, and in the same manner as in Example 18, the combination of baker's yeast, glucose, lactic acid bacteria and water, fermentation, and heat sterilization The powder of chlorella fermented product was obtained by spray drying.
Example 21
Chlorella cultured in a natural culture pond using sunlight is harvested and repeatedly washed and concentrated with water at 4 ° C under cooling (4 ° C), so that the chlorella suspension has a solid content of 10% by weight. A turbid liquid was obtained. In addition, by setting the frequency | count of washing | cleaning less than the comparative example 3, the free pheophorbite value of the chlorella after washing | cleaning was 5 mg%.

Using the suspension obtained in this manner, the suspension was not subjected to the blanching treatment, and in the same manner as in Example 18, the combination of baker's yeast, glucose, lactic acid bacteria and water, fermentation, and heat sterilization The powder of chlorella fermented product was obtained by spray drying.
Example 22
Chlorella cultured in a natural culture pond using sunlight is harvested and repeatedly washed and concentrated with water at 4 ° C under cooling (4 ° C), so that the chlorella suspension has a solid content of 10% by weight. A turbid liquid was obtained. In addition, by setting the frequency | count of washing | cleaning less than the comparative example 3, the free pheophorbite value of the chlorella after washing | cleaning was 10 mg%.

Using the suspension obtained in this manner, the suspension was not subjected to the blanching treatment, and in the same manner as in Example 18, the combination of baker's yeast, glucose, lactic acid bacteria and water, fermentation, and heat sterilization The powder of chlorella fermented product was obtained by spray drying.
Comparative Example 4
Chlorella cultured in a natural culture pond using sunlight is harvested and repeatedly washed and concentrated with water at 4 ° C under cooling (4 ° C), so that the chlorella suspension has a solid content of 10% by weight. A turbid liquid was obtained. In addition, since the frequency | count of washing | cleaning was set less than the comparative example 3, the free pheophorbite value of the chlorella after washing | cleaning was 20 mg%.

Using the suspension obtained in this manner, the suspension was not subjected to the blanching treatment, and in the same manner as in Example 18, the combination of baker's yeast, glucose, lactic acid bacteria and water, fermentation, and heat sterilization The powder of chlorella fermented product was obtained by spray drying.
Evaluation of the content of pheophorbite For Examples 18 to 22 and Comparative Examples 3 to 4, the content of free pheophorbite (mg%) and the total pheophorbite content in the chlorella suspension after the washing treatment ( mg%). The methods for measuring the free pheophorbite content (mg%) and the total pheophorbite content (mg%) are as described above.

Moreover, about chlorella fermented products (Examples 18-22 and Comparative Example 4) and the chlorella suspension (Comparative Example 3) after the heat sterilization treatment, the content (mg%) of free pheophorbide and the total pheophorb The bite content (mg%) was measured.
Evaluation of chlorophyll content From each of the fermented chlorella (powder) obtained in Examples 18 to 22 and Comparative Example 4 and the chlorella powder obtained in Comparative Example 3, 5 to 10 mg of each sample was collected. 10 mL of water was added to the sample and left for 30 minutes with occasional stirring. Next, 5 mL of an alkaline pyridine solution was added to the obtained suspension and allowed to stand for 15 minutes, followed by centrifugation, and the supernatant was collected. Next, 3 mL of an alkaline pyridine solution was added to the residue after centrifugation, allowed to stand for 15 minutes, then subjected to centrifugation, and the supernatant was collected and mixed with the previously obtained supernatant. Furthermore, the same amount of treatment as described above was repeated on the residue after centrifugation, so that the total amount of the supernatant was 10 mL. The alkaline pyridine solution used was prepared by adding water to 1.4 g of sodium hydroxide and 16.6 g of pyridine to adjust the total amount to 100 mL.

Next, with respect to the supernatant, the absorbance E ₄₁₉ at a wavelength of ₄₁₉ nm and the absorbance E _{454 at} a wavelength of ₄₅₄ nm were measured, and the content (μg) of chlorophyll per 1 mg of the sample was calculated by the following formula (1).
The absorbances E ₄₁₉ and E ₄₅₄ are values calculated by the following formula (2) using the transmitted light intensity I ₀ of the blank cell and the transmitted light intensity I of the sample cell at the respective measurement wavelengths. It is.

Evaluation of Flavor About the flavor and smell when actually eaten the fermented chlorella obtained in Examples 18 to 22 and Comparative Example 4 and the chlorella suspension after heat sterilization treatment obtained in Comparative Example 3 And evaluated. The evaluation was made in two stages, where B was the case where the original seaweed odor of Chlorella remained remarkably, and A was the case where the seaweed odor was reduced and was hardly felt.

  The results are shown in Table 7.

In Table 7, “total amount” for “content of pheophorbite” indicates “total amount of pheophorbite (mg%)”. Moreover, chlorophyll content is the value converted into g%.
As shown in Table 7, by reducing the content of free pheophorbite in the chlorella suspension to 10 mg% before the fermentation treatment, the pheophorphorus can be obtained without performing the blanching treatment before the fermentation treatment. A chlorella fermented product having a low bite content (specifically, after the fermentation treatment, the free pheophorbite content is 60 mg% or less and the total pheophorbite content is 80 mg% or less) was obtained.

Moreover, the content of chlorophyll can be maintained even after the fermentation treatment and the heat sterilization treatment by omitting the blanching treatment before the fermentation treatment from the comparison between Example 18 and Examples 19-22. It was.
The fermented chlorella of Examples 18 to 22 and Comparative Example 4 and the mixture of Comparative Example 3 all had a general viable count of 3000 cfu / mL or less, and the number of coliforms was negative. .

<Test Example 9>
Chlorella cultured in a natural pond using sunlight is harvested, washed and concentrated to adjust the solids content to 10% by weight. Further, the suspension thus obtained is cooled ( 4 ° C.) Washed repeatedly with 4 ° C. water. At this time, by appropriately adjusting the number of times of washing, sample 1 having a general viable count after washing of less than 300 cfu / mL, sample 2 having a general viable count after washing of about 3000 cfu / mL, and after washing A total of three samples (chlorella suspension) of sample 3 having a general viable cell count of approximately 10,000 cfu / mL were prepared.

  Subsequently, baker's yeast (dry yeast) 3.0% by weight, glucose 1.0% by weight, and lactic acid bacteria (Bifidobacterium longum BB536), respectively, with respect to the chlorella solid content of the chlorella suspensions of Samples 1 to 3 above. It fermented by mix | blending 0 weight% and water, and leaving still at 35 degreeC for 3 hours. The fermented solution thus obtained is sterilized by heating with steam at 100 ° C. for 1 minute, and then spray-dried to adjust the water content of chlorella to 5% by weight or less to obtain a chlorella fermented product. It was.

Among the above chlorella fermented products, those using sample 1 as a raw material, chlorella seaweed odor and fermentation odor were felt from the suspension after fermentation treatment, but after spray drying these odors were observed. It was greatly improved.
On the other hand, in the chlorella fermented product using the sample 2 as a raw material, both the suspension after the fermentation treatment and the fermented chlorella after the spray drying, the odor of chlorella and the fermentation odor were felt. The odor was of no problem in actual edible use.

Moreover, about the chlorella fermented product which uses the said sample 3 as a raw material, both the suspension after a fermentation process and the chlorella fermented product after spray-drying felt rot odor.
<Production example>
Production Example 1
30 kg of each chlorella fermented product obtained in Example 1 and Example 14 and 0.15 kg of xanthan gum as an excipient (binder) were charged into a blow granulator, and each was shaped into granules.

All of the granules thus obtained had no algae flavor and smell, were delicious and easy to eat.
Production Example 2
The fermented chlorella obtained in Example 1 and Example 14 were each molded with a tableting machine to produce a round tablet (1 tablet 200 mg).

All of the tablets thus obtained had no algae flavor and smell, were delicious and easy to eat.
The present invention is not limited to the above description, and various design changes can be made within the scope of the matters described in the claims.

  The method for producing a chlorella fermented food of the present invention is suitable as a method for producing an easily ingested chlorella fermented food by a simple treatment.

Claims (6)

  The chlorella is fermented with baker's yeast using a chlorella having a free pheophorbite content of 18 mg% or less and a general viable cell count of 8000 cfu / mL, which is negative for the number of coliforms. , Method for producing chlorella fermented food.   The method for producing a chlorella fermented food according to claim 1, wherein the chlorella before fermentation with baker's yeast is washed with water at 0 to 10 ° C.   A method for producing a chlorella-fermented food, characterized in that chlorella subjected to heat sterilization is fermented with baker's yeast.   Furthermore, it ferments in presence of saccharides, The manufacturing method of the chlorella fermented foodstuff in any one of Claims 1-3 characterized by the above-mentioned.   Furthermore, it ferments in presence of lactic acid bacteria, The manufacturing method of the chlorella fermented foodstuff in any one of Claims 1-4 characterized by the above-mentioned.   The method for producing a chlorella fermented food according to any one of claims 1 to 5, wherein the amount of the baker's yeast is 0.1 to 15% by weight based on the amount of the chlorella.