JPS63207359A - Defatted soybean - Google Patents

Abstract

PURPOSE:To obtain defatted soybean with excellent water solubility and flavor, having a relation between water solubility and n-hexanal content thereof satisfying specific condition and capable of providing a soybean protein having excellent flavor in high yield. CONSTITUTION:Defatted soybean having x and y taking values within the range indicated by oblique lines in the graph of the figure on the assumption that NSI (water solubility) is x and TBA values (ppm value of n-hexanol content) is y. The above-mentioned soybean is obtained by roughly crushing soybean simultaneously deficient in two or more lipoxygenase isozymes, skinning the roughly crushed soybean, rolling the skinned soybean and defatting the rolled soybean.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to defatted soybeans that are excellent in both water solubility (NSI) and flavor.

(Conventional technology) Defatted soybeans are important as raw materials for various soy protein products.

In order to obtain a soybean protein product with good flavor, defatted soybeans with good flavor are required. For this reason, various research and developments have been carried out,
It has become clear that poxygenase is significantly involved in the development of green plants. Many methods have been developed for producing soybean protein using defatted soybeans with lipoxygenase inactivated or in a state where lipoxygenase is not active.

Practically speaking, most lipoxygenase inactivation methods involve heating. Therefore, as lipoxygenase is thermally inactivated, soybean protein is also thermally denatured, and only defatted soybeans with low NSI can be obtained. Therefore, when protein is extracted with an aqueous solvent, such as isolated soybean protein or tofu, the yield is low. It has some problems.

In addition, in the case of concentrated soybean protein obtained using an acidic aqueous solvent, N
If the SI is low, there is also a problem that the emulsifying property and gel forming property are poor.

If you place emphasis on yield and nutrition, you will need to use defatted soybeans with a high NSI, but defatted soybeans with a high NSI are less likely to be denatured by heat, and of course lipoxygenase has not been deactivated, so the flavor will be lower. There is a problem that only poorly defatted soybeans, soybean protein products, tofu, etc. can be obtained. Furthermore, if the NSI is low, there is a problem that it is difficult to organize the textured soybean protein.

That is, defatted soybeans with high NSI and good flavor are not known.

Incidentally, in recent years, it has become possible to cultivate soybeans in which several of the isozymes of glue boxygenase in soybeans are genetically deleted at the same time, and the prospect of obtaining high yields of soybean protein products with less grassy odor is becoming possible.

For example, in the Nikkei Sangyo Shimbun dated November 8, 1986, blue (
There is an article about the commercialization of a new variety of "Sayaka soybean" that has no grains or bitterness (processing and production of soy milk yogurt, tofu, natto, etc.). In addition, JP-A-61-170359 discloses food raw materials (soy milk) and processed products (processed soy milk products) made from L-2 and L-3 deleted soybeans. Furthermore, JP-A-61-170359 discloses bean sprouts with reduced green bean odor using L-2 and L-3 deleted soybeans. or,
■Japanese Society of Agricultural Chemistry, (10) 1071-1078
(1985), Professor Kitamura describes lipoxygenase L-2. L-
It is reported that several lines of soybean with 3 simultaneous deletions have been obtained, and that the grassy odor is almost completely eliminated. Furthermore, ■Journal of Japan Food Industry Association 31 (11), 751-758.19
84) discloses the breeding of soybeans with reduced lipoxygenase by Professor Kitamura.

(Problem to be solved) For conventional defatted soybeans, the lower the NSI, the better the flavor.
, those with high NSI had poor flavor.

Furthermore, if you try to obtain good flavor from conventional defatted soybeans, you will have the following problems. ■In the heating process of defatted soybean production, delicate and complicated heating process management is difficult. ■If the defatted soybean raw material is heat-treated to inactivate lipoxygenase, soybean protein with good flavor can be obtained, but the protein is denatured by heating and the yield of soybean protein obtained by water extraction is reduced.

(Means for solving the problem) As one way to achieve the above objectives and solve the problem, if we use soybeans that have been genetically bred to be deficient in lipoxygenase, which has now been made possible, the conventional heating process for deactivating lipoxygenase will be unnecessary. Therefore, without causing a decrease in NSI, the NSI
The present invention was based on the knowledge that defatted soybeans and soybean oil with good flavor can be obtained even when the soybeans are high, and that by using these defatted soybeans, soybean protein with improved soybean odor, bitter taste, astringency, etc. can be obtained in high yield. I have reached the point where I have completed the . In particular, the nige flavor is a taste that irritates the throat.
The cause of this was said to be polyphenols in soybeans, but the defatted soybeans of the present invention have no bitter taste.

That is, the present invention is a defatted soybean whose NSI is X and whose TBA value is y, which is an arbitrary value of X and y within the range represented by the diagonal line in the graph of FIG.

X represents the NSI of defatted soybeans and is defined as follows. Precisely weigh 3.5 g of defatted soybeans, add 100 ml of deionized water, stir and extract at 40°C for 1 hour, centrifuge at 1000 g, take the supernatant into a volumetric flask, add deionized water to the residue, and add 2. The second extraction was performed in the same way, and the obtained supernatant was combined with the first supernatant to make a constant volume, and filtered (filter paper No. 6).
) Measure nitrogen in the filtrate using the Kelpool method, and use this as water-soluble nitrogen. The nitrogen in the defatted soybean sample is measured using the Kelpool method, and this is taken as the total nitrogen. NSI is the value obtained by dividing water-soluble nitrogen by total nitrogen and multiplying it by 100.

As shown in Figure 1, 50≦x; 5100 is also possible, but 65
≦X≦100 is preferable, and 70≦X≦92 is more preferable. This is because the soybean protein has a good flavor and a high NSI, so the extraction efficiency of soybean protein with a good flavor is high. Conventional defatted soybeans usually do not have good flavor unless X≦65,
The defatted soybean of the present invention has good flavor even when X≧65. The higher the value of
Skimmed soy milk, etc.) can be obtained.

y represents the TBA value, which is determined as follows.

Sample 10g and tax ionized water 50m i! Homogenize to form a homogeneous suspension and transfer to a distillation flask using 45 ml of deionized water. Add 4N hydrochloric acid 5-1 to this, immediately steam distillate, and distillate 50I1
Take 1. 0.1% ferrous chloride aqueous solution lIlβ and 5 mjl of TBA (thiobarbic acid) solution were added to 41IIIl of this effluent, and after heating at 70°C for 35 minutes, it was heated in running water for 10
Cool for a minute. The absorbance of this at a wavelength of 450 nm is measured using a spectrophotometer. On the other hand, the standard curve of n-hexanal was similarly examined in advance, and the amount of n-hexanal in the sample was calculated, which was taken as the TBA value (n-hexanal Opp weight). Note that the TtlA solution is 2-
Thiobarbic acid dissolved to a concentration of 0.02M was used.

As shown in FIG. 1, it is preferable that y≦50,
More preferably, y≦40. Most conventional defatted soybeans have a value of around ) r = 130 when x = about 90, and even if heat treatment is applied to reduce the value of Ta. However, even if the defatted soybean of the present invention has a high value of X of around 90, it has a good flavor with y=40 or so.

Although it depends on the degree of defatting, the size of flakes, etc., the oil content of the defatted soybeans of the present invention is usually 3% or less, and most of the time it is 1% or less. Depending on the purpose of the defatted soybean, it may have a certain amount of oil content (for example, 3 to 8%).

The roughness of the defatted soybean of the present invention depends on the type of soybean and the degree of dehulling, but it is usually in the range of 40 to 65%, preferably in the range of 45 to 60%.

The crude fiber content of the defatted soybeans of the present invention is usually 1 to 5%, preferably 1.5 to 4.5%.

A method for producing defatted soybeans that is simultaneously excellent in both NSI and flavor as in the present invention will be exemplified.

This is a method for producing defatted soybeans, which is characterized by defatting soybeans that have simultaneously deleted two or more lipoxygenase isozymes.

Lipoxygenase isoenzymes are L-1, L-2 and L
-3, and the defatted soybean of the present invention is characterized by defatting soybeans lacking two or more of these isozymes. Although soybeans with simultaneous deletion of three isozymes have not yet been obtained, soybeans with genetic deletion of lipoxygenase L-2 and L-3 at the same time (hereinafter abbreviated as L-2,3-deficient soybeans), lipoxygenase L Soybeans in which -1 and L-3 are genetically deleted at the same time (hereinafter abbreviated as L-1,3-deficient soybeans) have been obtained. The soybeans that have two or more lipoxygenase isoenzymes deleted at the same time for use in the present invention include -2° L-3 deleted soybeans, L-1 and L-3 deleted soybeans, and the like.

For example, for L-2,3-deficient soybeans, the method of Kitamura et al.
985) ; Journal of Japan Food Industry Association 31 (11)
, 751-758.1984)) can be used. Also, L-1,3
The missing soybeans obtained by Kitamura et al. can also be used.

Soybeans lacking two or more lipoxygenase isoenzymes at the same time may be defatted by crushing or the like, but it is preferable to defatt by crushing, removing the skin, and pressing.

For the coarse crushing, soybeans lacking two or more lipoxygenase isozymes at the same time can be used as they are, but it is preferable to pre-dry the soybeans to a moisture content of about 8 to 12% so that they can be easily removed. For drying, known means such as hot air drying can be used. In order to inactivate the conventional soybean lipoxygenase and keep the NSI as high as possible, delicate temperature control was required, but soybeans lacking two or more of the lipoxygenase isozymes used in the present invention are responsible for the quality of the flavor. Since the content of polypoxygenase is small, there is no need to intentionally inactivate it by heating, or even if the sheet metal is heated, a small amount of heating is sufficient, and therefore temperature control is extremely easy. In addition, for coarse crushing, it is sufficient to divide the mixture into two pieces, and a known means (for example, a cracking roll, etc.) can be used.

Hulling can be carried out by coarsely crushing soybeans or by wind selection of soybeans that have simultaneously deleted two or more poxygenase isozymes.

In order to facilitate the subsequent degreasing process, it is appropriate to press the sheet to a thickness of about 0.50+m using a known means such as a roll. Depending on the application (for example, defatted soybeans with different oil contents), the width of the compression can be arbitrarily changed.

Soybeans that have been compressed or have two or more boxygenase isoenzymes deleted at the same time are treated with organic solvents (e.g., le-hexane, alcohol, methyl ethyl ketone, acetone, other azeotropes, etc.), or supercritical gases such as carbon dioxide in a supercritical state. It can be degreased using, etc. In the case of ordinary soybeans, strict temperature control is required in consideration of the inactivation of lipoxygenase, but in the present invention, temperature control is easy by using soybeans that have simultaneously deleted two or more lipoxygenase isozymes. At the same time, defatted soybeans that have been defatted by solvent extraction are usually heated to evaporate the remaining solvent, but in the present invention, strict temperature control has been performed in consideration of the deactivation of poxygenase in conventional defatted soybeans. By using soybeans that have two or more poxygenase isozymes deleted at the same time, temperature control is easy.

The defatted soybean obtained in this way has an NSI of defatted soybean.
Let X be the TBA value and y be the TBA value, which is included in the shaded range of the graph in FIG. That is, defatted soybeans with high NSI (and good flavor) can be obtained.

Therefore, when isolated soybean protein, concentrated soybean protein, etc. are produced using the defatted soybean of the present invention, soybean protein with excellent flavor can be obtained in high yield without using any means such as separate Al-Ali extraction.

In addition, the soybean oil obtained by defatting has a better flavor than conventional soybean crude oil even in its crude state, and has extremely little reversion and depth compared to soybean oil refined by deoxidizing and deodorizing.

(Example) Embodiments of the present invention will be described below with reference to Examples.

Example 1 Lipoxygenase L-2, L-3 simultaneous deletion soybean (L-2
゜L-3 deletion soybean) and lipoxygenase L-1. L-
3 simultaneous deletion soybeans (L-1, L-3 deletion soybeans) at a temperature of 75
Dry with hot air at ℃, coarsely crush into two pieces using a Graf King roll, remove the seed coat by air sorting, form into flakes with a thickness of 0.5 mm using a pressing roll, and use n-hexane to remove the seed coat. Fats and oils were extracted and heated using a membrane solvent to obtain defatted soybeans. (
Table 1 below shows the NSI and TBA values of the defatted soybeans obtained.

(Margin below) Table-1 However, for No. 2 and No. 6, 14 is used instead of hot air drying.
Using soybeans that were fluidized and heated at 0°C for 11 seconds, No. 3 was 14
Using soybeans that were fluidized and heated at 0°C for 15 seconds, No. 4 was 14.
Soybeans that had been fluidized and heated at 0°C for 17 seconds were used.

In addition, the oil content (OC) of the obtained defatted soybeans was approximately 0.5%,
Crude protein (CP) was between 51-54% and crude fiber (CF) between 2-3.5%.

(Margin below) Further, the TBA value was measured as follows.

10g sample and 50m deionized water I! The mixture was passed through a homogenizer to form a homogeneous slurry, which was then transferred to a distillation flask using 45 ml of salt ionized water. Add 5nl of 4N hydrochloric acid to this, immediately steam distillate, and 50ml of distillate
j! Take. To this distillate 4II11, 1 ml of 0.1% ferrous chloride aqueous solution and 5 ml of TBA (thiobarbic acid) solution.
ml was added, heated at 70°C for 35 minutes, and then cooled in running water for 10 minutes. The absorbance of this at a wavelength of 450 nm was measured using a spectrophotometer. On the other hand, the standard curve of n-hexanal was similarly investigated in advance, the amount of n-hexanal in the sample was calculated, and the TBA value (ppr weight of n-hexanal) was calculated.
And so. The TBA i solution was prepared by dissolving 2-thiobarbic acid in a 90% acetic acid solution to a concentration of 0.02M.

The NSI was measured as follows. Precisely weigh 3.5 g of defatted soybeans, add too many liters of deionized water, stir and extract at 40°C for 1 hour, centrifuge at 1000 g, take the supernatant into a volumetric flask, and add deionized water to the residue. In addition, a second extraction was performed in the same manner, and the resulting supernatant was combined with the first supernatant,
Keep the volume constant and filter (Toyo Roshi N).

, 6) Nitrogen was measured in the filtrate by Kelsol method, and this was taken as water-soluble nitrogen. Nitrogen in the defatted soybean sample was measured using the Kelsol method, and this was taken as total nitrogen. NSI was calculated as the percentage of water-soluble nitrogen divided by total nitrogen.

OC was extracted using Soxhlet and ethyl ether.

For CP, nitrogen X6.25 was used as crude protein by Kelsol method.

CF was determined by the modified Henneberg-Staumann method.

The relationship between NSI and Tl5A values is plotted in Figure 1. (L-2, L-3-deleted defatted soybeans are indicated by ・, L-1
, L-3-deleted defatted soybeans are indicated by a circle. ) Comparative Example 1 Soybeans produced in the United States were treated in the same manner as in Example 1 to obtain defatted soybeans. However, the heating conditions corresponded to those in Table 1 above.

(Left below) Table-2 No. 1 2 ・3 4
5 However, No. 4 was defatted using soybeans heated in a fluidized bed at 140°C for 11 seconds, and solvent removal was performed at 95°C for 12 minutes. In addition, No. 5 was degreased using soybeans heated in a fluidized bed at 140°C for 20 seconds, and the solvent was removed at 95°C for 12 minutes.

OC is about 0.5%, CP is about 52%, CF is about 3.2%
Met.

The relationship between NSI and TBA values is plotted in Figure 1.

(Indicated by an x mark.) Experimental Example 1 (Comparison of flavors) (blank below) 20 panelists tested 1 part by weight of each of the defatted soybeans obtained in Example 1 and Comparative Example 1 to 4 parts by weight of water. were added to form a suspension, and the participants ate the samples and ranked them according to their flavor.

the result. The order of flavor was as follows.

No. of Table-1, 4>No. of Table-1, 3=No. of Table-2,
5>No. of Table-1, 2=No. of Table-1, 6>N of Table-1
o, 1 > No. of Table-2, 4 = No. of Table-1, 5 >
No. of Table-2, 3 > No. of Table-2, 2 > No. 1 of Table-2
It was 1.

(Effects) As described above, the present invention has made it possible to produce defatted soybeans with a high NSI and good flavor, and compared to the conventional production method for defatted soybeans, the heating process for deactivating lipoxygenase is required. It is no longer necessary (it can be made weaker if necessary), making it easier to manage the process of defatted soybean production. The soybean oil obtained at the same time is also crude and has an excellent flavor.

In addition, (1) using the defatted soybean of the present invention has the effect that soybean protein with excellent flavor can be obtained at a high yield.

[Brief explanation of the drawing]

FIG. 1 is a drawing showing the relationship between N5I (x-axis) and TBA value (y-axis). × is normal defatted soybean, O is L-1, L-3 lipoxygenase-deficient defatted soybean,
represents L-2, L-3 lipoxygenase-deficient defatted soybean.

Claims (1)

[Claims] (1) Defatted soybeans whose NSI is x and whose TBA value is y, where x and y are arbitrary values within the shaded range of the graph in FIG.