JPS6125337B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a method for maintaining the quality of a flour improving agent using raw soybean flour and/or defatted soybean flour having lipoxidase activity by preventing a decrease in lipoxidase activity during storage. Regarding. There is an enzyme called lipoxidase (lipoxygenase) in soybeans. It is well known that this oxygen oxidizes certain unsaturated fatty acids and lipids containing them to produce peroxides, which oxidize pigments in flour, etc., resulting in a decolorizing effect. In addition, in the case of foods made from wheat flour, such as bread, it improves its texture, texture, etc., and delays aging, and in the case of noodles, it strengthens the waist and gives it an elastic texture. Since soybean flour has a variety of useful functions, attempts have been made to utilize soybean flour having lipoxidase activity as a wheat flour improving agent. However, the problem with using soybean flour as a wheat flour improver is that the lipoxidase activity is significantly reduced. That is, when raw soybeans, defatted soybeans, etc. are powdered and stored, their lipoxidase activity rapidly decreases, and the flour improver effect is also lost. This decrease in activity is particularly significant in the case of defatted soybean powder, and therefore, unless the powder is prepared each time it is used, it is impossible to obtain soybean flour that achieves the purpose of improving wheat flour, which is time-consuming and uneconomical. Of course, if you use soybean flour with reduced enzyme activity, the desired improvement effect will appear if you use it extensively, but it is unavoidable that it will give food the odor, taste, color, etc. of soybeans, so it is not practical. isn't it. Furthermore, when raw soybeans are powdered, in addition to a decrease in lipoxidase activity, the lipids contained therein are rapidly oxidized, so that they immediately develop a rancid odor during storage and cannot be used as food. For the reasons mentioned above, although the effect of soybeans as a wheat flour improver is well known, up to now there has been little industrial use of this. The present inventors have repeatedly conducted research on the industrial use of soybeans as a wheat flour improver, and have found that in order to prevent a decrease in lipoxidase activity during storage, it is necessary to use raw soybean flour and/or defatted soybean flour that has this enzyme activity. It has been found that it is extremely effective to store a wheat flour improver using 10% oxygen concentration in an environment with an oxygen concentration of 10% or less, and that this significantly suppresses the decrease in lipoxidase activity. That is, the present invention provides raw soybean flour and/or defatted soybean flour having lipoxidase activity, and a wheat flour improving agent prepared by adding grain flour, starch, protein powder, etc. thereto, if necessary, in an environment with an oxygen concentration of 10% or less. The gist of the present invention is a method for maintaining the quality of a wheat flour improving agent using natural products, which comprises preventing a decrease in the lipoxidase activity during storage. In the present invention, the flour improver having lipoxidase activity needs to be stored in an environment with an oxygen concentration of 10% or less. The reason is clear from the following experimental example. Experimental example Raw soybean flour with lipoxidase activity (lipoxidase activity 1800) and defatted soybean flour (lipoxidase activity 1700) were placed in a glass container and degassed to oxygen concentrations of 0, 5, 10, and 15%, respectively. It was then sealed and stored at 30°C. 1, 3, and 6 months after the start of storage, take a portion of each sample, manufacture gyoza skin according to the following recipe, and use a color difference meter to determine the color difference using a sample to which no soybean flour is added as a control. The elasticity and texture were compared through sensory tests. (1) Method for making gyoza skin (a) Blend Wheat flour (unbleached all-purpose flour) 500 grams Salt 5 Water 165 Raw soybean flour or defatted soybean flour 5 (b) Process Mixing 15 minutes (room temperature 27℃) Layering 2 times Rolling 4 times (0.7 mm thickness) (2) Method for measuring color difference The gyoza skin produced as described above was placed in a plastic bag and left at room temperature for 2 hours, and then measured using a color difference meter (manufactured by Nippon Denshoku Kogyo Co., Ltd.). I went. The measurement results were expressed as the color difference √ ΔL ² +Δa ² +Δb ² between the soybean flour-added product and the additive-free product (control).
However, ΔL, Δa, and Δb represent the difference in brightness and a value (green-red) and b value (blue-yellow) from the control, respectively. (3) Sensory test The ingredients were wrapped in the skins of the soybean flour-added and control dumplings and steamed for 15 minutes, after which a sensory test of elasticity and texture was conducted by a panel of 20 experts. Both elasticity and texture were evaluated using the following 3-level scoring system based on the control. Much better than the control...3 Better than the control...2 Same or worse than the control...1 (4) Results a Color difference The relationship between stored oxygen concentration and color difference is shown in Figures 1 (raw soybean flour) and It is shown in Figure 2 (defatted soybean flour). It is clear that in both raw soybean flour and defatted soybean flour, when the oxygen concentration during storage exceeds 10%, the color difference value decreases rapidly. That is,
It has been shown that when a flour improver with lipoxidase activity is stored in an environment with an oxygen concentration of 10% or more, the effect of improving the hue of dumpling skin decreases rapidly as the lipoxidase activity significantly decreases. ing. Even when compared with the naked eye, gyoza skin made using raw soybean flour and defatted soybean flour stored at an oxygen concentration of 15% has a certain degree of hue improvement effect compared to the control, but the extent of this effect is not practical. It wasn't the point. b Sensory test The results of the sensory test for each storage period are shown in Table 1 (raw soybean flour) and Table 2 (defatted soybean flour).
The results were shown as the average score.

【table】

[Table] As is clear from the above, when any sample is stored at an oxygen concentration of 10% or less, its elasticity
Both the texture and texture are significantly better than the control, but when the oxygen concentration is 15%, both the firmness and the texture are almost the same as the control. That is, oxygen concentration
Soybean flour stored in an environment with a concentration of 10% or more has a significant decrease in lipoxidase activity, and no practical quality improvement effect can be expected at all. As is clear from this experimental example, by storing soybean flour having lipoxidase activity in an environment with an oxygen concentration of 10% or less, a decrease in the enzyme activity can be effectively prevented. It is clear that the enzyme activity rapidly decreases under conditions where the oxygen concentration exceeds 10%. In this experimental example, the skin of dumplings was shown as an example, but the same results were obtained for other general foods made from wheat flour, such as bread and noodles. It is clear that preservation of flours is extremely effective in preventing a decrease in lipoxidase activity. In the present invention, methods for reducing the oxygen concentration to 10% or less include vacuum degassing, inert gas substitution,
Any method may be used, such as a method using an oxygen absorber. Soybean flours with lipoxidase activity include powdered whole soybeans, broken soybeans, or flakes obtained by rolling them, powdered soybeans swollen with water, and powdered defatted soybeans. These can be used alone or in a mixture at an appropriate ratio. The deterioration rate of the lipids in soybean flour is slowed down when stored in an environment with an oxygen concentration of 10% or less, so even with long-term storage, there is no deterioration in flavor due to the generation of off-flavors, and there are no practical problems at all. do not have. Further, these soybean flours may be mixed with grain flours such as wheat flour and rice flour, starches such as potato starch and corn starch, protein flours such as gluten powder and skim milk powder, etc., if necessary. Depending on the intended use, inorganic substances such as potassium bromate, ammonium chloride, calcium carbonate, monosodium phosphate, etc., which are generally used as yeast food, may be added. The flour improver treated to prevent the decrease in lipoxidase activity by the method of the present invention can be stored for a long time without reducing its flour improver effect and is convenient to transport, so it can be used at any time and place. Moreover, it is economically advantageous because it can be carried out at low cost. In addition, since it uses natural products, it is completely safe and harmless from a food hygiene perspective, and has the advantage of being useful in nutritionally enriching flour foods. Example 1 A flour improver made by thoroughly mixing 2 parts of cornstarch with raw soybean flour obtained by finely pulverizing dehulled and coarsely crushed soybeans (produced in Illinois, USA) was placed in an air-impermeable bag with an oxygen absorbent (( It was sealed together with 3 tablets/Kg (manufactured by Taipack Co., Ltd., trade name: "Jyorikku A") and stored at 25°C for 6 months. Note that the oxygen concentration in the bag was 2%. Regarding this flour improving agent, at the start of storage and after 3 months of storage, gyoza skins were produced in the same manner as in the above experimental example, and color difference measurements and sensory tests (elasticity, texture) were performed using the flour improving agent without using the flour improving agent as a control.
As a result, the values for color difference at the start and after storage were 6.4 and 6.0, respectively, and for elasticity and texture, both at the start and after storage, all panelists judged it to be much better than the control. . Therefore, no decrease in the improving effect of the wheat flour improving agent was observed during storage for 6 months, and it is clear that the lipoxidase activity was maintained at the level at the start of storage even after 6 months. Example 2 A flour improver made by thoroughly mixing 5 parts of wheat flour with 20 parts of low-temperature extracted defatted soybeans (NSI85) pulverized to 100 mesh was placed in a glass container, and the oxygen concentration inside was set to 5%. The air in the container was replaced with nitrogen gas until then, and the container was sealed and stored at 30°C for 3 months. For this wheat flour improving agent, dried noodles (Hiyamugi) were manufactured as follows at the start of storage and after 3 months of storage, and color difference measurements and sensory tests for elasticity (body) and texture were conducted using noodles without this flour improving agent as a control. Ivy. (1) Manufacture of dry noodles (a) Mixture Flour (unbleached all-purpose flour) 100 parts Salt water (12 Baume degree) 33 Flour improver 1 (Addition is omitted for control product) (b) Process Mixing 〓 15 minutes Overlapping 2 times Rolling 4 stages of rolls Cutting blade No. 20 square Drying Continuous method up to 5% moisture (2) Color difference measurement Same as the above experimental example. (3) Sensory test Noodles were boiled in boiling water for 5 minutes, then cooled by immersing them in running water, and then tasted by a panel of 20 experienced people using separately prepared noodle soup to evaluate the elasticity and texture of the noodles. did. The scoring method was the same as in the above experimental example. As a result, the color difference values at the start of storage and after 3 months of storage were 6.2 and 5.6, respectively, and regarding elasticity and texture, both at the start and after storage, all panelists agreed that the additive addition was better than the control. I found it to be much better. From these results, it is clear that the quality improvement effect of the flour improver did not decrease during storage, and that the lipoxidase activity maintained its initial level even after storage.

[Brief explanation of the drawing]

FIGS. 1 and 2 are diagrams showing the relationship between oxygen concentration and color difference during storage of raw soybean flour and defatted soybean flour having lipoxidase activity, respectively. In each figure, the vertical axis represents color difference, the horizontal axis represents oxygen concentration, and curves 1, 2, and 3 represent the 1st, 3rd, and 6th month of storage, respectively.

Claims (1)

[Claims] 1. Raw soybean flour and/or defatted soybean flour having lipoxidase activity, and flour improvers made by adding grain flour, starch, protein powder, etc. thereto as necessary, must be stored in an environment with an oxygen concentration of 10% or less. A method for maintaining the quality of a flour improving agent using a natural product, which method comprises preventing a decrease in the lipoxidase activity.