JP4547545B2 - Cereal seed extract and use thereof - Google Patents

Description

  The present invention relates to a cereal seed extract and use thereof.

  When starch is heated with moisture, it absorbs the moisture and swells to cause “gelatinization”. This characteristic is widely used in various foods such as udon and bread. However, starch paste that has been manufactured for a long time has a phenomenon called “aging”. Specifically, it has such phenomena as decreased water retention, solidified food, weakened gel, water separation and decreased digestibility. Cause, not only the quality of food but also the value of goods.

  In order to prevent aging of starch, a quick freezing method, a surfactant, use of additives such as β-amylase and trehalose have been conventionally attempted (for example, Patent Document 1, Patent Document 2, Patent Document 3, Patent (Ref. Literature 4, Patent Literature 5, Patent Literature 6, Patent Literature 7, Patent Literature 8, Patent Literature 9, and Patent Literature 10).

However, conventional methods for preventing starch aging have the following problems. For example, in the quick freezing method, there is a problem that a special device or equipment is required, and in the method using a surfactant, there is a problem that a food has a taste or smell. Further, the method of adding β-amylase has a problem that it is necessary to strictly control the temperature in the production process, and the original texture of starch is lost. The method of adding trehalose has a problem that the flavor of starch food changes. For these reasons, there has been a strong demand for a simple starch aging prevention method that does not require special equipment and that does not impair the flavor and the like of the starch food.
JP 58-086050 A JP 60-199355 A JP-A 63-267246 JP-A-64-060341 Japanese Patent Application Laid-Open No. 64-080447 Japanese Patent Laid-Open No. 02-035049 Japanese Unexamined Patent Publication No. 03-061459 Japanese Patent Application Laid-Open No. 07-079689 Japanese Patent Laid-Open No. 08-242784 Japanese Patent Laid-Open No. 11-042057

  Therefore, an object of the present invention is to provide a technique that can easily prevent aging of starch without requiring special equipment, strict temperature control, etc., and with little change in the flavor of food.

  In order to achieve the above object, the present invention provides an extract from cereal seeds that accumulates antifreeze proteins in leaves, the cereal seeds being stored at a low temperature of not less than 1 week and not more than 4 ° C., From the above, an extract extracted with an aqueous solvent is used.

  If the extract from the grain seeds of the present invention is added to starch, aging of starch can be suppressed, and in particular, aging of starch can be effectively prevented even when frozen or refrigerated. Moreover, even if the extract of this invention is added, there is little influence with respect to the flavor of a foodstuff. The cereal seed extract of the present invention can be prepared without the need for special equipment and facilities, and the method of use thereof is, for example, a very simple method of adding only during food production. In addition, the extract of the present invention has a water retention function in addition to the antiaging effect of starch, but has no antifreeze activity.

  Next, the present invention will be described in detail.

  First, the background to the present invention is as follows. Plants that inhabit low temperature environments are acclimatized to low temperatures by inducing and synthesizing necessary components under low temperatures. Although studies of such adaptive responses have been widely conducted, until now, there has been little research on those seeds, assuming that their composition has not changed. On the other hand, the present inventors focused on the point that cereal seeds, which are said to contain a large amount of starch, do not deteriorate the composition even in a low-temperature environment. Based on this hypothesis, we conducted a series of studies based on the hypothesis that ingredients with preventive functions were included. As a result, the inventors have found that an extract from cereal seeds stored at a low temperature contains a component that prevents starch aging.

  Aging of starch is a phenomenon that occurs as a result of starch molecules dispersed by gelatinization re-aggregating in the course of cooling and free water in the tissue is released, which can be evaluated as a reduction in the degree of gelatinization. it can. The detailed mechanism of starch aging has not yet been clarified.

  Next, the extract of the present invention is an extract of cereal seeds, which can be produced, for example, as follows.

  First, prepare grain seeds. The cereal seed is not particularly limited as long as it is a cereal seed that accumulates antifreeze protein in the leaves. Examples thereof include winter rye, spring wheat, winter wheat, spring rye, winter barley, and spring oats, preferably winter Rye, spring wheat, winter wheat, spring rye, more preferably winter rye and winter wheat.

  Next, the said grain seed is preserve | saved under low temperature. The storage temperature is not particularly limited as long as it is in a low temperature state of 4 ° C. or lower, and the lower limit of the storage temperature is not particularly limited, but is preferably −80 ° C. or higher, for example. A preferable range of the storage temperature is −80 to 4 ° C., and a more preferable range is −20 to 4 ° C.

  The storage period is, for example, 1 week, preferably 1 to 5 weeks.

  Next, the extract of the present invention is obtained by extraction from the cereal seed stored at a low temperature using an aqueous solvent. The aqueous solvent is not particularly limited, and examples thereof include water, physiological saline, and buffer solution, and among these, buffer solution is preferable. In the buffer, the pH is, for example, pH 5.0 to 8.0, preferably pH 6.5 to 7.5, and the ionic strength is, for example, 10 to 100 mM, preferably 10 to 50 mM. Examples of the buffer solution include a phosphate buffer solution and a sodium acetate buffer solution, and preferably a phosphate buffer solution.

  The extraction method is not particularly limited, and for example, grain seeds may be immersed in the aqueous solvent, and then the aqueous solvent may be recovered. In the extraction, it is preferable to grind the grain seeds in order to increase the extraction efficiency. The extraction temperature is not particularly limited, and is, for example, 4 to 20 ° C, more preferably 4 to 10 ° C. The extraction time is not particularly limited, and is, for example, 10 to 20 minutes, preferably 10 to 15 minutes.

  Thus, although the extract of the present invention is obtained, the present invention is not limited to the above-described production method.

  In the present invention, the form of the cereal seed extract is not particularly limited, and may be, for example, liquid, sol, solid, or powder, and is appropriately selected depending on the use form.

  The extract of the present invention has an anti-starch action and a water retention effect, but does not have antifreeze activity.

  Next, the starch anti-aging agent of the present invention contains the extract of the present invention. Moreover, the starch foodstuff of this invention contains the starch anti-aging agent of the said this invention. As described above, the cereal seed extract of the present invention has an anti-starch aging effect, so that it can be used to prevent starch aging of food, and even when the food is refrigerated or frozen, It is possible to suppress the solidification of the starch contained in the product, and it is possible to maintain the same quality as the state before storage even after refrigeration or frozen storage. Therefore, the starch food is preferably a refrigerated food or a frozen food.

  Examples of the starch food include rice balls, udon, cooked rice, rice cakes, dumplings, bread, bread dough, pasta, pie dough, Western confectionery, Japanese confectionery, and the like.

  The proportion of the cereal seed extract of the present invention added to the food is, for example, 0.01 to 0.1 weight of the extract protein with respect to 100 parts by weight of the starch food, based on the protein of the extract. Part range, more preferably 0.01 to 0.05 parts by weight. Moreover, the ratio of adding the cereal seed extract of the present invention to food is, for example, based on the sugar amount of the extract, for example, the extract sugar amount is 0.015 to 100 parts by weight of starch food. The range is 0.15 parts by weight, more preferably 0.015 to 0.075 parts by weight.

  Next, the water retention agent of the present invention contains the grain seed extract of the present invention. As described above, the extract not only suppresses the solidification of the starchy substance, but also can play a role of retaining water in the cell in order to suppress sublimation of water in the cell, for example. The water retention agent of the present invention can be used, for example, added to food additives, cosmetics, pharmaceuticals and the like. That is, the food additive, medicine and cosmetic of the present invention contain the water retention agent of the present invention.

  Next, examples of the present invention will be described together with comparative examples. The present invention is not limited to these examples.

(Preparation of seed extract)
10 g of winter rye seeds were weighed into four plastic dishes and stored at −80 ° C., −20 ° C., 4 ° C., and 20 ° C. for 1 week. The seeds after storage were washed with pure water and pulverized using a miller. 30 ml of 10 mM potassium phosphate buffer (pH 7.0) was added to 10 g of the crushed seeds and stirred sufficiently, followed by centrifugation (8000 × g, 15 minutes). The supernatant was filtered using a sterile filter with a pore size of 0.45 μm (manufactured by ADVANTEC: trade name: DISMIC), and the filtrate was used as an extract. In addition, the extract preserve | saved at -80 degreeC, -20 degreeC, and 4 degreeC was made into Example 1-1 of this invention, and the thing preserve | saved at 20 degreeC was made into comparative example 1-1.

(Contained protein and sugar content)
The total amount of protein contained in the extract was measured by the Bradfor method using a protein assay kit manufactured by BIORAD. Furthermore, the total amount of sugar contained in the extract was measured by the phenol-sulfuric acid method using glucose as a standard substance. The results are shown in Table 1 below.

(Table 1)
Protein amount (mg / g) Sugar amount (mg / g)
Comparative Example 1-1
20 ° C 13.4 19.7
Example 1-1
4 ° C 13.1 23.9
−20 ° C. 15.1 23.5
−80 ° C. 12.6 22.1
(Extract composition)
The composition of the extract (stored at −20 ° C.) was examined. The results are shown in Table 2 below. The moisture content is measured by the heat drying method under reduced pressure, the protein is measured by the Kjeldahl method (nitrogen / protein conversion factor: 6.25), the lipid is measured by the Soxhlet extraction method, and the ash content is measured by the direct ashing method. Sodium was measured by atomic absorption spectrophotometry. The carbohydrate was calculated by the following calculation formula (1). In addition, energy was calculated using an energy conversion factor (protein: 4, lipid: 9, carbohydrate: 4) according to nutrition labeling standards (2003, Ministry of Health, Labor and Welfare Notification No. 176).
Formula for calculating carbohydrate content (1): 100- (water + protein + lipid + ash)
(Table 2)
Moisture 97.5g / 100g
Protein 0.5g / 100g
Lipid Less than 0.1g / 100g Ash content 0.8g / 100g
Carbohydrate 1.2g / 100g
Energy 7kcal / 100g
Sodium 0.5g / 100g
(Ammonium sulfate fraction processing)
To the extract, ammonium sulfate (manufactured by Wako Pure Chemical Industries, Ltd.) was added to 80% saturated (w / v) ammonium sulfate, and equilibrated in ice for 60 minutes. The equilibrated solution was then centrifuged (15,000 × g, 15 minutes), and the precipitate was dissolved in 10 ml of 10 mM potassium phosphate buffer (pH 7.0). This solution was placed in a dialysis membrane (Wako Pure Chemical Industries, Ltd., trade name: Dialysis membrane, molecular weight cut-off 10,000), and this dialysis membrane was immersed in 10 mM potassium phosphate buffer (pH 7.0). The dialysis for 120 minutes was performed 3 times, and the solution after the dialysis was used as an ammonium sulfate fraction sample.

(Antifreeze activity measurement)
By using a phase contrast microscope with a cooling temperature control (Olympus: trade name BX-50, Rinkham: trade name LK600-PM) and observing the form of ice crystals, the antifreeze active protein in the extract The presence or absence was judged.

  First, a sample was prepared using the ammonium sulfate fraction sample so that the amount of protein was 100 μg / ml. 1 μl of the sample was dropped on a circular cover glass, the cover glass was placed on the microscope, and the temperature of the microscope was adjusted to 20 ° C. Next, after cooling to −40 ° C. at a rate of 100 ° C./min, the temperature is increased to −5 ° C. at the rate, and further heated at a rate of 5 ° C./min, and the number of ice crystals decreases. The temperature was increased and decreased at a rate of 1 ° C./min so that a single crystal was formed in the microscope field. When the single crystal grew into a circular disk shape, it was judged that there was no antifreeze activity, and when it grew to other shapes (for example, hexagonal shape, diamond shape, etc.), it was judged that there was antifreeze activity. The result is shown in FIG. As shown in the figure, all samples stored at 20 ° C., 4 ° C., −20 ° C., and −80 ° C. grew in a circular disk shape, and none of the samples had antifreeze activity.

(Starch aging test (BAP method))
1. Preparation of dehydrated powder sample The extract is added to wheat starch (manufactured by Wako Pure Chemical Industries, Ltd.) so that the final concentration is a sugar concentration of 100 μg / g or a protein concentration of 10 μg / g to prepare a 5% wheat starch suspension. did. After 15 g of the suspension was completely heat-gelatinized by an autoclave (121 ° C., 20 minutes) to form starch paste, it was stored at 10 ° C. for 1 day or −15 ° C. for 1 week. 70% ethanol, three times its weight, was added to the starch paste after storage, and dewatered by stirring and centrifugation (8000 × g, 10 minutes). In addition, the starch paste preserve | saved at -15 degreeC was used after defrosting in running water. After repeating this operation three times using the precipitate, adding 3 times its weight of acetone to the precipitate, stirring and centrifuging (8000 × g, 10 minutes), dealcoholization Processed. The precipitate was left to dry overnight in a desiccator, and then further pulverized using a mortar and pestle to obtain a dehydrated powder sample.

2. Preparation of additive-free dehydrated powder sample An additive-free dehydrated powder sample was prepared in the same manner as the method for preparing the dehydrated powder sample except that the extract sample was not added.

3. β-Amylase / Pullanase Treatment β-Amylase solution (SIGMA, Type1-B: Sweet potato-derived 10,000 unit / 0.5 ml) 16.19 ml and pullulanase solution (Seikagaku Corporation, Crude from Klebsiella pneumoniae, 2 μl of 2,100 unit / g) was dissolved in 100 ml of 0.8 M sodium acetate buffer (pH 6.0) and stirred well to prepare a β-amylase / pullulanase enzyme solution.

  Distilled water (2 ml) was added to each dehydrated powder sample (20 mg) and sufficiently homogenized using a glass homogenizer. First, 0.8 M sodium acetate buffer was added to 0.8 ml of this solution to make 10 ml, and this was used as a suspension sample. Next, 40 μl of 10N NaOH is added to 0.8 ml of the remaining solution and completely dissolved at 50 ° C. for 5 minutes. Then, 0.4 ml of 2N acetic acid is added to adjust the pH to 6.0, and then 0.8M acetic acid is added. Sodium buffer was added to make 10 ml, which was used as an alkali gelatinized sample.

  First, 0.25 ml of the enzyme solution which had been heat-inactivated was added to 1 ml of the suspension sample, which was used as a blank. Next, 0.5 ml of the enzyme solution was added to 2 ml of the alkali gelatinized sample and reacted at 40 ° C. for 30 minutes. After the reaction, the enzyme in the sample was heat-inactivated by heat treatment for 5 minutes, and this was used as a sample for quantification.

  Using the stock solution of the sample for quantification, the amount of reducing sugar (Somoginelson method) was quantified. In addition, the total amount of sugar (phenol sulfuric acid method) was quantified using the same sample diluted 10 times.

(Degree of gelatinization)
The degree of gelatinization (%) was calculated using the following formula. In the following formula, K ₁ is the amount of reducing sugar in the suspension sample, K ₂ is the total amount of sugar in the suspended sample, B ₁ is the amount of reducing sugar in the blank, and A ₁ is alkali gelatinization. The amount of reducing sugar in the sample and A ₂ represents the total amount of sugar in the alkali gelatinized sample.
Degree of gelatinization (%) = {(K ₁ −B ₁ ) / K ₂ } / {(A ₁ −B ₁ ) / A ₂ }
The obtained values are shown in Table 4 below. It can be said that the aging of starch progresses, so that the value of gelatinization degree is small. In addition, the extract preserve | saved at -20 degreeC and 4 degreeC was made into Example 1-2 of this invention, and the thing preserve | saved at 20 degreeC and the additive-free thing were made into comparative example 1-2.

(Table 4)
Comparative Example 1-2 Example 1-2
Gelatinization degree (%)
No addition 20 ℃ 4 ℃ -20 ℃
Frozen storage (-15 ° C)
Protein equivalent addition 50 78 100 100
Sugar equivalent addition 48 100 98
Refrigerated storage (10 ℃)
Protein equivalent addition 14 48 88 100
Sugar equivalent addition 91 100 100
In addition, the protein conversion addition and the sugar conversion addition in Table 4 are the addition of the extract sample to starch at a protein concentration of 10 μg / g in the preparation of the dehydrated powder sample, respectively, and the starch conversion at a sugar concentration of 100 μg / g. It represents what was added.

  As shown in Table 4 above, in Example 1-2, aging of starch was almost prevented. On the other hand, in Comparative Example 1-2, aging of starch was confirmed.

(Starch aging test (physical properties))
The extract samples (Example 1-1 and Comparative Example 1-1) were added so that the final concentrations were a sugar concentration of 100 μg / g or a protein concentration of 10 μg / g, respectively, and 10% wheat starch suspension was added. 400 g of turbid liquid was obtained. This was put into a 2 L Erlenmeyer flask and heat gelatinized by an autoclave (121 ° C., 20 minutes). Next, after storing at 4 ° C. for 1 day or at −20 ° C. for 7 days, the upper dry portion was scraped off and the distortion was measured with a rheometer (manufactured by Yamaden Co., Ltd .: trade name CREEP METERRE2-33005S). Load cell 20N, Load MAG 1, storage pitch 0.03, measurement speed 5 mm / sec, contact surface diameter 16 mm). Prepared using the sample of Example 1-1 and measured the result as Example 1-3, prepared using the sample of Comparative Example 1-1, and measured the result as Comparative Example 1-3, The results are shown in Table 5 below. It can be said that starch aging is progressing, so that a distortion rate (%) is small. In addition, the sample preserve | saved at -20 degreeC was used after defrosting in running water.

(Table 5)
Frozen (-20 ° C, 7 days) Refrigerated (4 ° C, 1 day)
Comparative Example 1-3
No addition 14.90 47.60
20 ° C. 15.76 35.34
Example 1-3
4 ° C 31.32 51.67
−20 ° C. 25.95 52.14
−80 ° C. 24.62 −
The temperature in a table | surface shows the temperature which preserve | saved the grain seed in preparing an extract.

  As shown in Table 5, when Example 1-3 is compared with Comparative Example 1-3, in any case of refrigeration and frozen storage, a decrease in distortion rate is suppressed in any sample of the example. It had been.

  Moreover, the distortion rate was measured by the method similar to the above using the ammonium sulfate fraction sample (-20 degreeC storage seed) (4 degreeC, 1 day). The results are shown in Table 6 below. In addition, the ammonium sulfate fraction sample prepared from the seed preserve | saved at 20 degreeC was set as Comparative Example 1-4, and the ammonium sulfate fraction sample prepared from the seed preserve | saved at -20 degreeC was set as Example 1-4.

(Table 6)
Refrigerated (4 ° C, 1 day)
Comparative Example 1-4 31.53
Example 1-4 65.94

  In this example, the grain seed extract of the present invention is applied to a rice ball.

  Grain in the same manner as the seed extract preparation method of Example 1, using winter rye stored at −20 ° C. for 1 week, winter wheat stored at −20 ° C. for 5 weeks, and spring wheat stored at 4 ° C. for 5 weeks. Each seed extract was prepared. Each said grain seed extract was added at the time of rice cooking so that protein concentration might be 20 microgram / g with respect to rice and water. After cooking rice balls, rice balls were prepared, each rice ball was covered with a wrap, and stored at 10 ° C. for one day in a state of being blocked from the outside air. Similarly, a rice ball without the addition of the grain seed extract was prepared and stored at 10 ° C. for 1 day.

  Each rice ball after storage was subjected to a rupture stress test using a rheometer (manufactured by Yamaden Co., Ltd .: CREEP METERRE2-33005S) (Load cell 20N, Load MAG 1, storage pitch 0.03, measurement speed) 5 mm / sec, contact surface diameter 16 mm). The results are shown in Table 7 below.

(Table 7)
Breaking stress strain rate
Comparative Example 2
Before storage 3.6 × 10 ⁴ Pa −
No addition (10 ° C, 1 day storage) 8.5 x 10 ⁴ Pa 26.3%
Example 2
Winter rye (10 ° C, 1 day storage) 6.0 × 10 ⁴ Pa 30.8%
Winter wheat (10 ° C, 1 day storage) 6.2 × 10 ⁴ Pa −
Spring wheat (10 ℃, 1 day storage) 6.5 × 10 ⁴ Pa −
As shown in Table 7, the additive-free rice balls of Comparative Example 2 rose to nearly 2.5 times the breaking stress before storage. On the other hand, in the rice ball of Example 2, the water resistance of the rice ball was maintained and its solidification was suppressed. As a result, the breaking stress changed only about 1.5 times. Therefore, it is clear that the grain seed extract of the present invention has an excellent anti-starch aging effect when added to food.

  The cereal seed extract of the present invention has a starch aging prevention function and a water retention function, and therefore has a wide range of uses such as foods, pharmaceuticals, and cosmetics.

It is a photograph which shows evaluation of the antifreeze activity of an example of the extract of this invention.

Claims (12)

An extract from cereal seeds that accumulates antifreeze protein in leaves,
The cereal seeds are seeds of any one of winter rye, spring wheat, winter wheat, spring rye, winter barley and spring oats;
An extract obtained by storing the cereal seeds at a low temperature of -80 ° C to 4 ° C for 1 week or longer and extracting the cereal seeds with a buffer solution having a pH of 5.0 to 8.0. The extract according to claim 1, wherein the cereal seeds are seeds of any one of winter rye, winter wheat and spring wheat. The extract according to claim 1 or 2, wherein the storage period of the grain seed is 1 to 5 weeks. The extract according to any one of claims 1 to 3, wherein the buffer is a phosphate buffer. The extract according to any one of claims 1 to 4, wherein the form is liquid, gel, solid or powder. Starch antiaging agent containing the extract in any one of Claim 1 to 5. A starch food comprising the starch antiaging agent according to claim 6. The starch food according to claim 7, which is for refrigeration or freezing. The starch food according to claim 7 or 8, which is at least one selected from the group consisting of rice balls, udon, cooked rice, rice cake, dumplings, bread, bread dough, pasta, pasta dough, pie, puff pastry, Western confectionery and Japanese confectionery. A water retention agent comprising the extract according to any one of claims 1 to 5. The food additive containing the water retention agent of Claim 10. Cosmetics containing the water retention agent of Claim 10.

Images