JPS5948624B2 - Production method of soybean meal and crude soybean oil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing soybean meal and crude soybean oil, and more specifically, a method for activating and deactivating enzymes during production. Dry to a constant moisture content in a temperature range where the enzyme retains its activity, then increase the temperature to a temperature range where the enzyme is inactivated, heat it with dry heat or moist heat to inactivate the enzyme, and then perform compression and solvent extraction according to conventional methods. This is a method for producing soybean meal and soybean crude oil that have not been degraded by enzymes, by removing solvent from meal and degumming from oil.

More than 20 enzymes have been reported to exist in soybean seed cells.

In order to maintain its own life, the soybean seeds undergo subtle biochemical reactions in response to changes in environmental conditions.
Generally, the enzyme activity of plant seeds is at its lowest when they are dormant, but when they absorb water and the amount of water inside the cells increases, enzyme metabolism increases and preparations for germination begin.

Furthermore, when a plant seed is mechanically injured and its cells are destroyed and exposed to oxygen in the air, enzyme activity is said to rapidly increase for self-defense. The acceleration of metabolism caused by enzymes associated with the increase in water content of the plant seeds described above is centered on the decomposition of polysaccharides, the oxidative decomposition of lipids, the synthesis of proteins, and the consumption of vitamins. This includes the generation of free fatty acids from neutral fats by oxidation, the isomerization of fat and the generation of peroxide radicals by lipoxygenase, the generation of non-hydrated phospholipids and choline from phospholipids by phospholipase, and the synthesis of enzyme proteins from amino acids.

As a result of secondary reactions caused by the above-mentioned oxidative decomposition products, the production of volatile odorous substances such as various alcohols, aldehydes and ketone compounds, the oxidation of unsaponifiable substances such as tocopherol, and the production of protein thiol groups. Many undesirable reactions that lead to quality deterioration of soybean meal and crude oil proceed in a chain reaction, such as oxidation of soybean meal and changes in functional properties, and oxidative discoloration of pigments such as carotenoids. In order to understand the changes in the properties of crude oil due to changes in the moisture content of soybeans, soybeans with a moisture content of 12% were humidified or dried at a temperature range that maintains enzyme activity (for example, 90°C or less), and seven types of soybeans with different moisture contents were analyzed. Prepare soybeans,
Table 1 shows a comparison of the oil extracted from each oil and its properties.

In Table 1 above, soybean moisture 1.9% is the constant moisture value at a temperature of 85°C, soybean moisture 5.7% is the constant moisture value when dried in the sun, and soybean moisture 7.8 and 10.1% are the constant moisture values when the soybean moisture is dried in the sun. Value of soybean water taken out during sun drying, moisture 1
2.1% is the moisture content of the sample soybean, and the soybean moisture content of 14.8 and 17.6% is the value obtained by placing the sample in a pin, adding the calculated amount of water, mixing it tightly, and leaving it at room temperature overnight. It is. According to Table 1 above, increases in activities such as enzyme hydrolysis and oxidation occur with an increase in water content, resulting in an increase in the acid value of the extracted oil, a decrease in the iodine value, an increase in conjugated dienes, an increase in phospholipids, and an increase in total tocopherols. This is manifested as a decrease in

In particular, when drying to a constant moisture content of 1.9% at a temperature range that maintains enzyme activity, that is, below 90°C, the total tocopherol content in the crude oil reaches a maximum value of 1.9 mg/g, while the phospholipid content reaches a maximum of 0.9 mg/g. It was found that it shows a minimum value of 36%. On the other hand, considering the fact that mechanical injury to plant seeds such as soybeans increases enzymatic activity, it is found that when soybean cells are destroyed by the mechanical injury, a peroxidation reaction involving oxygen in the air occurs instantaneously. The resulting peroxide radicals rapidly undergo secondary oxidation of coexisting substances, and in the case of soybeans, carbonyl compounds and ionone, a decomposition product of carotene, which are the causative agents of the characteristic bean odor, are produced.

The bean odor that appears as a self-defense effect is so bad that humans cannot tolerate it, and it odors and contaminates the oil.To remove it, the deodorization process is generally carried out at 250°C and 4mmH.
It is difficult to say that it is practical because steam distillation treatment is required under high temperature and high vacuum conditions. What should be noted here is that
Some of the above-mentioned primary and secondary oxidation reactions associated with water absorption in soybeans are reversible as long as the tissue cells are healthy and the enzymes are active; This means that a reduction reaction occurs.

For example, water 13%, total tocopherols 1.25mg/g
When soybeans (4) are dried to a moisture content of 1.9%, the total tocopherols increase to 1.90 mg/g, but when this is humidified to a moisture content of 18.0%, the total tocopherols are 0.33
mg/g. Also, the soybean (4) has a moisture content of 18.2
%, total tocopherols decreased to 0.28 mg/g, and when this was dried to a moisture content of 1.9%, total tocopherols increased to 1.87 mg/g, and when this was further humidified to a moisture content of 18.3%, total tocopherols decreased to 0.28 mg/g. Total tocopherols are again 0.
It decreased to 34 mg/g. In other words, as soybeans absorb water, lipoxygenase activity increases and the concentration of fatty acid radicals increases, which reacts with tocopherol radicals and tocopherols turn into inactive dimers and oxides such as tocolets, creating substances that cause color reversion. When the water content decreases and the concentration of peroxide radicals decreases, the tocopherol returns to its original active form and repeats the reversible change. However, in this case, reversible oxidation or reduction accompanying the increase or decrease of intracellular water is possible only when the cells are in a healthy state, and after the cells have been crushed by compression etc. Even if the water content is lowered, the reverse reaction will not occur. Now, if we focus on the behavior of the soybean enzyme groups mentioned above and examine the currently known soybean oil extraction methods, we will find the following two
I can point out two shortcomings.

(1) After carefully selecting soybeans, only if the soybeans have a high moisture content, dry them slightly to reduce the moisture content to around 11%.
% or less is not dried, so the moisture content of raw soybeans entering the pretreatment process is usually considered to be 9 to 12%.

By the way, under this moisture condition, some of the soybean tocopherols have already changed into dimers and quinones and have lost their activity. Active tocopherol is an essential factor to prevent oil oxidation and increase stability during and after oil extraction, and it is important to extract oil when the amount of active tocopherol in raw soybeans has decreased. This will reduce the (2) Soybeans are crushed, heated (below 90°C), and pressed to destroy the cells, and then subjected to solvent extraction, but as a result, the enzyme activity is retained and the cells are damaged. become.

Since the extraction process is proceeded with the enzyme activity level increased due to the damage, the primary oxidation by the enzyme of neutral fats, phospholipids, proteins, pigments, etc., of non-combatable substances such as neutral fats, phospholipids, and pigments, is carried out between the time of pressing and the completion of extraction. , secondary oxidation proceeds rapidly.
In this case, the appearance of bean odor peculiar to soybeans as a biological defense reaction is particularly noticeable during the extraction process, and it smells and contaminates all of the oil, meal, and phospholipids. During this time, phospholipids are decomposed into non-hydrated phospholipids and bitter choline. In addition, the SH group of miR protein is secondarily oxidized to S by peroxide radicals produced by lipoxygenase in the presence of oxygen.
-S bond, which causes discoloration of carotenoid pigments and decreases nutritional value and palatability. Therefore, the quality of the meal and oil obtained is considerably degraded and contaminated due to oxidation and hydrolysis based on enzyme action, compared to the quality when it existed in the raw material soybean cells. Furthermore, soybeans, which are the raw material for oil extraction, are organisms that have the ability to germinate, so if soybeans are dried and reduced to a constant moisture content at a temperature below 90°C, which preserves life, the enzyme activity of soybeans becomes weak, and the intracellular substances of soybeans are affected by the reduction effect. oxides are reduced.

For example, there is a decrease in free fatty acids, non-hydratable phospholipids, tocopherol oxides, pigments, etc. in oil, and a decrease in soybean protein oxides, bittern, etc. In other words, oxides are reversibly reduced to the maximum extent at the cellular level of soybeans or coarsely ground soybeans due to the inherent reducing action of life development. Therefore, the production of free fatty acids, non-hydratable phospholipids, tocopherol oxides, pigments, soy protein oxides, bitterness, etc. is suppressed to a minimum, reducing the acid value of soybean oil and increasing the total tocopherol content. By reducing soybean moisture in the pretreatment process, it is possible to improve the quality of the final product, such as reducing color reversion and improving the nutritional value and palatability of soybean meal. Next, after reduction at the cellular level by drying, the soybeans that still retain enzyme activity are removed at a temperature range of 90°C, which deactivates the enzyme.
Rapidly raise the temperature above ℃ or heat it with dry heat or moist heat to deactivate the enzyme and lose the vitality of the soybean.

As a result, even if the cells are destroyed in the subsequent process, the oxidation and hydrolysis effects by enzymes remain suspended, resulting in the development of bean odor, the production of non-hydratable phospholipids, tocopherol oxides, etc. There is no generation of protein oxides, bitterness, etc. After the above two steps, namely the dry reduction step and the heating step, the following steps are followed by pressing, solvent extraction, desolventizing the meal, and degumming the oil, resulting in denaturation with enzymes,
Soybean meal and crude soybean oil that have not undergone deterioration have the following characteristics. (1) Crude soybean oil, soybean gum and soybean meal with no soy odor can be obtained, and the palatability of each can be greatly improved.

(2) Soybean meal has minimal quality deterioration due to oxidation of sulfur-containing amino acids, has a yellow powder odor, is more palatable, and has high nutritional value.

(3) The crude oil has the highest tocopherol content, in addition to being free of tocopherol oxides, as well as non-hydratable phospholipids,
Free fatty acids, pigments, conjugate acids, etc. are all in very small amounts, and degummed crude oil with good hydration properties can be obtained. By omitting deacidification and only using white clay treatment and light deodorization, it is possible to obtain high-quality, highly nutritious crude oil with high oxidation stability. Refined oil is obtained.

In addition, before the extraction process, the coarsely crushed soybeans undergo heat denaturation due to enzyme deactivation treatment, and the water-soluble protein content has already decreased. Both amounts will decrease significantly.

Therefore, it is very useful for preventing the formation of balls, saving energy, and reducing solvent loss. Conventionally, a known soybean oil extraction method using enzyme deactivation (for example, Japanese Patent Application Laid-open No. 142409/1983) is a method for producing edible oil from crude soybeans, in which (a) 12 to 25% by weight of unextracted soybeans are extracted;
using soybean oil obtained from soybeans by humidifying to a water content of , heat treatment at a temperature of 90-120°C, and subsequently extracting the crude soybean oil from the treated material with a non-polar solvent; (b) using a special acid; This is a method for producing edible oil from crude soybean oil, which is characterized in that soybean oil that has been delecithinized by a known method is subjected to a bleaching process without a sliming process, and then deoxidized and deodorized simultaneously in a known manner.

However, all of these known soybean oil extraction methods do not perform reduction treatment that utilizes the enzyme activity of raw soybeans, and they destroy cells by crushing them while maintaining enzyme activity, and then attempt to deactivate the enzyme. It is something that exists. This invention was invented to solve the above-mentioned drawbacks, and the intracellular proteins, neutral fats, phospholipids, pigments, vitamins, etc. of raw raw soybeans and coarsely crushed soybeans are stored in a dormant state with an extremely low moisture content. By doing so, we succeeded in extracting oil while keeping the oxidation level to a minimum.

In other words, the raw raw soybeans and coarsely crushed soybeans are dried to a constant moisture content or 8% or less in a temperature range that maintains enzyme activity, and then heated, dry heat, or moist heat to a temperature range that deactivates the enzyme. To provide a method for producing soybean meal and crude soybean oil that have not been degraded by enzymes, in which enzymes are inactivated using conventional methods, followed by pressing, solvent extraction, desolventizing the meal, and degumming the oil. It is something. Here, the temperature range in which the enzyme activity is maintained is, for example, 90°C or lower, and the temperature range in which the enzyme is inactivated is the above-mentioned 90°C or higher.

To describe in detail the characteristics of the present invention, a reduction reaction is carried out in the cells of raw raw soybeans and coarsely crushed soybeans at a temperature of 90°C or less using enzyme activity, and a part of the previously produced The oxide is reduced to a highly physiologically active state, and then 9
After adding water vapor to a temperature above 0°C to inactivate the enzyme and stop the oxidation reaction, the oil is extracted by pressing, solvent extraction, removing the solvent from the meal, and gumming it in accordance with conventional methods. The present invention provides a method for producing soybean meal and crude soybean oil that have not undergone deterioration.

By doing the above, this invention makes it possible to obtain a soybean meal that is free from oxidation and contamination, contains highly active and nutritious proteins, has a high total tocopherol content, has no bean odor, and is non-toxic. A crude oil with a trace amount of hydratable phospholipids and high oxidation stability that is easy to purify can be obtained.

Next, a comparison of the conventionally known soybean oil extraction method with the method of the present invention is as follows.

(1) According to the conventionally known soybean oil extraction method, meal and crude oil are produced which are partially contaminated with quality deterioration and bean odor, bitterness, etc. due to oxidation and hydrolysis based on enzyme action.

As a result, the color tone of the meal, the strength of the bean odor and bitterness, the functional characteristics of the protein, the total tocopherol content of the crude oil, the bean odor, the content of non-hydratable phospholipids and choline, the difficulty of purification,
The oxidative stability of the refined oil, the color tone, taste, oxidative stability, emulsifying property, etc. of the soybean lecithin obtained in the degumming process are inferior to the products produced by the method of the present invention. In addition, in known soybean oil extraction methods that do not add enzyme deactivation, raw soybeans may be lightly dried, but the soybean moisture content after drying does not drop below 9%, so the reduction reaction within the cells is partially stopped and insufficient.

Another advantage of the method of the present invention is the nature of phospholipids in the extracted oil.

In other words, the main components of phospholipids present in raw soybeans are highly hydrating phosphatidylcholine (lecithin), etc.
When oil is extracted without enzymatic deactivation, it is subjected to the hydrolytic action of phospholipase in the extraction process after cell destruction to produce a hydrolyzate. In the case of soybeans, the main primary hydrolysis products are phosphatidic acid and choline as non-hydratable phospholipids. Oil obtained by solvent extraction is usually converted into soybean crude oil through a process in which water is added to hydrate the phospholipids and centrifuged to remove hydrated lecithin using the difference in specific gravity (degumming process). However, phosphatidic acid and other non-hydratable phospholipids produced as hydrolysates through the hydrolytic action of phospholipase remain dissolved in the oil and remain in the crude oil, increasing the phospholipid content of the crude oil. Part of the purpose of the treatment with caustic soda and activated clay in the conventional purification process is to remove remaining non-hydratable phospholipids. 1) Furthermore, the phospholipids in the extracted oil obtained by the method of the present invention are not peroxidized by lipoxygenase or decomposed by phospholipase, so they maintain healthy physiological activity and sufficient hydration. .

Therefore, in the degumming process performed by adding water, we produce highly active soybean lecithin that has no bean odor, no bitterness due to choline, and has a light color and good flavor, and a soybean lecithin that has a low content of non-hydratable phospholipids and has no bean odor. It is possible to obtain light colored crude oil. The crude oil obtained in this process has a low acid value, a trace amount of non-hydratable phospholipids, a high total tocopherol content, and no bean odor, so the alkali treatment carried out in the usual refining process is omitted, and the It can be made edible with only activated clay treatment to remove trace amounts of gum and dissolved metals and light deodorization treatment. That is, by light deodorization, it is possible to prevent tocopherols from distilling out and allow them to remain, and at the same time, it is possible to reduce heat deterioration of the oil and increase the nutritional value of the oil. That is, it is possible to greatly simplify the known soybean oil refining method and produce a high-quality edible oil with high nutritional value and high oxidation stability, and its value is high from the standpoint of resource and energy conservation. Example soybeans were pre-selected by conventional sieving and sorting to remove foreign accompanying substances, and then dried in a vertical air heating dryer to reduce the moisture content from 11.5% to 3% by blowing hot air at 80°C. 1/ with roller
The soybeans were coarsely crushed to 8 to 1/16 fractions, and then the enzymes were deactivated by moist heat heating in a horizontal multi-tube steam heater at a temperature of 100° C. and a residence time of 20 minutes.

The enzyme-deactivated coarsely crushed soybeans were humidified to a water content of 8% using a paddle mixer, sent to a smooth roller, pressed into soybean flakes with a thickness of about 0.3 mm, and then extracted. Soybean flakes are extracted with industrial hexane using a filtration type extractor, and the extraction time is approximately 1.5% until the residual oil content in the soybean meal is approximately 0.5% or less.
Extracted by time. Soybean meal with hexane is desolventizer tossed. In the evening, it was subjected to solvent removal and heat treatment, dried in a meal dryer, passed through an air cooler, and sized with a meal sieve and meal roller to obtain soybean meal. The soybean meal obtained in this way does not have the raw soy odor characteristic of soybeans.
A strong yellow and fragrant yellow powder odor is imparted to the rice.Table 2
A soybean meal with the following characteristic values was obtained.

On the other hand, the extracted micella was subjected to several steps of evaporation and distillation to obtain crude soybean oil with a phospholipid content of 2.1%.

This soybean crude oil was hydrated and degummed by adding 2% water using a conventional method.
to obtain soybean crude oil. The crude lecithin centrifuged in this step also lacked the raw grass odor characteristic of soybeans, and was given a new aromatic flavor. Soybean lecithin produced from crude lecithin by filtration and dehydration is a high-quality soybean lecithin with a rich yellow powder odor and enhanced palatability. Degummed soybean crude oil has extremely low residual phospholipid of 0.02%, acid value 0.3, color (mouth pivot method 25.4 mm cell) yellow 20-red 4, and is of good quality with no raw soy odor. be. Steam refining of the soybean crude oil thus obtained was attempted as follows.

That is, after pretreatment with 0.2% phosphoric acid, the aqueous layer is centrifuged, omitting alkaline deacidification, decolorized using 2% activated clay in a conventional manner, filtered, and sent to a deodorizing device (210).
It was deodorized for 120 minutes at ℃ (steam amount: 3%, degree of vacuum: 5 mmHg) to obtain lightly refined soybean oil with little distillation of infightable substances. The refined soybean oil had a good flavor. Control Example Raw soybeans of the same type as those used in the examples were sieved in a conventional manner, and immediately after sorting before sorting, they were divided into 1/8 to 1/8 cracks using a grooved roller.
The soybeans are coarsely crushed into 16 pieces, then heated with a horizontal multi-tube steam heater until the temperature of the crushed soybeans reaches 70℃, and then crushed with a smooth roller to about 0.0℃.
It was pressed into soybean flakes with a thickness of 3 mm.

Next, the soybean flakes were treated in the same manner as in the example to obtain soybean meal and crude soybean oil. On the other hand, soybean crude oil is processed by conventional methods such as hydration degumming, acid treatment, alkali deacidification, decolorization, and deodorization (250
℃, 3 mmHg) to obtain purified soybean oil. The properties of the soybean meal and soybean oil (crude oil, crude oil, refined oil) obtained in these Examples and Control Examples are as shown in the following table.

Claims (1)

[Claims] 1 Raw soybeans or coarsely crushed soybeans are dried to a constant moisture content within a temperature range in which the enzyme retains its activity, and then heated to a temperature range in which the enzyme is inactivated by dry heat or moist heat to release the enzyme. A method for producing soybean meal and soybean crude oil that have not been degraded by enzymes, by deactivating soybean meal and deactivating soybean oil, and carrying out pressing, solvent extraction, desolventizing the meal, and degumming the oil according to the following conventional methods. 2. The manufacturing method according to claim 1, wherein the temperature range in which the enzyme activity is maintained is 90° C. or lower. 3. The temperature range in which the enzyme is inactivated is 90°C or higher;
A manufacturing method according to claim 1. 4. The manufacturing method according to claim 1, wherein the constant water content is 8% or less. 5. After the enzyme is inactivated, if necessary, the water content is adjusted to 8 to 12%, and the following steps are carried out according to conventional methods: compression, solvent extraction, desolvation of the meal, and degumming of the oil. The manufacturing method described in paragraph 1.