JPS5852622B2 - Manufacturing method for extracted vegetable protein - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides isolated protein (at least 85-90% protein)
Alternatively, the present invention relates to a method for producing extracted vegetable protein, which is known as concentrated protein (approximately 70% protein).

Plant protein-rich extracts, such as isolated or concentrated proteins, are prepared by grinding the seeds or other elements of plants.

If the seeds are previously treated with a fatty solvent, such as hexane, a "defatted" flour is obtained.

To obtain separated proteins, defatted or unreadable fat powder is mixed in an alkaline medium (pH = 7-14) or an acidic medium (pH = 1-14).
3.5), the insoluble residue is separated and washed, and the washing water is mixed with the soluble fraction.

This soluble fraction is then adjusted to the isoelectric pH value of the protein and precipitated to obtain a good yield and quality.

For example, in the case of soybean protein, it is brought into contact with an alkaline medium of pH 8 and precipitated at pH 4.5, resulting in approximately 80-90%
The dissolved protein is recovered in the form of separated protein and has a protein content of at least 85-90% on dry matter.

The remainder of the dry matter includes soluble carbohydrates, salts and organic compound-bound proteins.

Among these, phytic acid (myo-inositol-6 phosphate)
is about 1.5-2% of dry matter.

To obtain concentrated protein, the defatted powder is washed with an aqueous medium such as water at the isoelectric pH value of the protein and the protein-rich solid residue is separated from the supernatant.

The dry matter of this residue contains polysaccharides, salts and organic compounds, of which approximately 1.2-1.7% is phytic acid.

In both cases, the protein fraction contains biologically active proteins, including, among other things, significant amounts of trypsin inhibitors.

The presence of phytic acid and trypsin inhibitors has a detrimental effect on the value of extracted proteins as nutrients.

In fact, trypsin inhibitors can cause pancreatic enlargement and reduced growth rate in young rats.

Phytic acid can form complexes with many metal cations essential to life such as calcium, iron, magnesium and zinc, thus reducing their availability and reabsorption in the intestine.

Extracted proteins have been obtained which are substantially free of at least one of the undesirable substances mentioned above, but these extracted proteins can be obtained by using enzymatic treatments or technical treatments such as ultrafiltration. or produced by incubating raw materials at temperatures above ambient temperature for long periods of time.

The method of the present invention provides an effective and simple way to obtain high quality vegetable extracted protein compared to prior art methods.

The present invention provides that a plant-extracted protein with a low content of trypsin inhibitors, fuicenic acid and oligosaccharides can be produced by separating the plant-extracted protein in solid form from an aqueous medium containing it, and this aqueous medium is pH greater than .0 and less than or equal to 5.7, preferably from 5.3 to 5.5
Based on the knowledge that H.

"Isoelectric pHJ" as used in the present invention means the isoelectric pH value of the protein in question or, for protein mixtures, the average isoelectric pH value identified at the minimum solubility.

This pH value is about 4.5 for most plant proteins, such as soybeans and cottonseed that have not undergone any particular treatment other than solubilization (ie, raw plant proteins).

In such a case, the pH value range according to the invention is 5.0.
~5.7 (excluding 5.0), preferably pH5.3 ~
5.5.

In one aspect of the invention, the plant-extracted protein is prepared by preparing a powder, isolated protein, or concentrated protein at an isoelectric pH of +0.5 units to an isoelectric pH of
It is preferable to wash with +1.2 units of aqueous medium and recover the remaining insoluble components as an extract.

Another aspect of the invention comprises: (1) suspending a plant flour in an alkaline aqueous medium having a pH of 7 to 14 or an acidic aqueous medium having a pH of 1 to 3.5; and (11) isolating the flour fraction that is soluble in the medium. , the plant-extracted protein is separated by precipitation at a pH greater than 5.0 and less than or equal to 5.7.

The method of the invention thus differs from conventional methods in that the effect p) (value is not the isoelectric pti value, but a substantially higher pH value.

Using this higher pH value is accompanied by a negligible decrease in quantitative yield (i.e. % amount of recovered protein), but this is further explained by the improved quality of recovered protein as described above. There are benefits.

It was established that the quantitative yield was generally reduced by 10-20%, while the phytic acid and trypsin inhibitor content was reduced by a factor of about 2-4 depending on the pH value used.

Oligosaccharide content is also reduced. As is known, plants from which useful extracted proteins can be obtained include crops, especially soybeans, sunflowers, corn, chinese beans, lima beans, castor beans, cotton, lotus, lupine, sesame, peanuts, cowpeas. (
Vignasinensis), legumes (I egminous) such as Egyptian beans, and oilseeds (ol).
eaginous) crops.

The flour used as a raw material, preferably defatted flour, is as described above.

The concentrated or separated protein, preferably further washed, used as starting material was defined as above.

These latter starting materials were all obtained in conventional manner at isoelectric pH values.

The pH value to obtain the plant extract protein is greater than 5.0; 5.
7 or less, preferably from 5.3 to 5.5, and can be suitably adjusted with any convenient agent, such as hydrochloric or phosphoric acid, acetate, buffer or caustic soda solution, caustic potash solution or carbonate buffer.

The pH value is a decisive factor for obtaining the desired extracted whitening in terms of quantity and quality.

For example, for the use of soybean, the phytic acid and trypsin inhibitor content decreases little below pH 5.0, but above pH 5.7 the quantitative loss becomes too great and the trypsin inhibitor content becomes too high again.

The method of the invention does not require special equipment or expensive chemicals or processing or any modification of existing production lines.

The soluble and insoluble fractions can be separated in a conventional manner, for example by decanting, filtration, centrifugation or any other technique.

The insoluble fraction obtained can of course be washed with water or with an aqueous solution having a pH value preferably greater than 5.0 and less than or equal to 5.7.

The extracted proteins can be used as such or after neutralization, optionally after standardization of their composition.

They can also be dried (spray-dried, freeze-dried, etc.)**.

They can be used in the food industry, especially in human food, especially in the diet.

Their nutritional value is greatly improved. The following examples illustrate the method of the invention.

In these examples the percentages are expressed by weight and the values according to the invention are indicated by an asterisk in the comparison table.

Example 1 Concentrated soybean protein Concentrated protein is made by mixing 100g of dehulled and defatted soybean flour with 19g of distilled water.
It is manufactured by suspending it in 00g.

The suspension was stirred for 1 hour at ambient temperature, then 6 fractions of 300 g each were taken and the pH values were adjusted with hydrochloric acid to 4.5, 5.0, 5.3, 5.5, 5.
7 and 6.0.

These fractions are then centrifuged at 3000 G for 15 minutes and the centrifuged precipitate is dried by lyophilization.

The amounts and composition of these dry fractions are shown in the following table.

It has been shown that the concentrated proteins produced at pH values between 5.0 and 5.7 are better than those produced at pH values 4.5 and without an unacceptable decrease in yield as at pH 6.0. It is.

Example 2 Isolated soy protein (by washing) and concentrated soy protein The following products 10.9 are washed with 50-200 g of water at a pH value of 5.5.

The suspension thus obtained is centrifuged at 3000 G for 15 minutes, and the insoluble residue is collected and dried.

Example 3 Soy protein isolate (by precipitation) Protein isolate is prepared from dehulled and defatted soybean flour as follows: 100 g of the flour is suspended in 1900 g of water, then p
Adjust the H value to 8.0 with caustic soda.

This suspension is centrifuged at 3000G for 15 minutes to obtain 1740**g of a powder solution containing 90% Kunshiro.

Make six identical fractions of 2809 each and add hydrochloric acid to the following pH values: 4.5, 5.0, 5.3, 5.5
.

Add to 5.7 and 6.0 to precipitate proteins.

These fractions are then centrifuged at 3000 G for 15 minutes, and the centrifugal precipitate is collected and dried by lyophilization.

The results are shown in Example 1. The quality of the isolated protein obtained at pH 5.0 to 5.7 is remarkable as for the concentrated protein of Example 1.

Example 4 Protein isolation (by precipitation) of soybeans, sesame, peanuts and Egyptian beans (a) Commercially available defatted soybean flour (BakerlSNutris) without prior heat treatment and having a high nitrogen solubility index
oy.

Archer Daniel Midlands) is suspended in a ratio of 60 g of powder to 540 g of water at pH 8.0.

After removing the insoluble portion by centrifugation, half of the supernatant was adjusted to pH
Acidify to pH 4,5 and the other half to pH 5,5.

(b) The same method was applied to another commercially available defatted soybean flour (■
※※ 5oyafluff 200W, Centra
l 5oya ).

The result is qualitatively the same as that of Example 3a, but the fact that this flour has been heat treated results in a lower quantitative yield.

(C) Apply this method to sesame flour.

Despite the extremely low solubility of the raw materials, the reduction in the proportion of phytic acid is evident.

(d) The method is successfully applied to defatted peanut flour.

The recovered tan days are in this case the same for both pH values.

(e) This method also applies to ground Egyptian beans.

A decrease in phytic acid content is also clearly shown here.

Example 5 Separated soy flour (by precipitation) 5 kg of defatted soy flour is suspended in 95 kg of water, then the pH value is adjusted to 8.2 and the insoluble fraction (Al
Centrifuge in a fa-Laval) machine.

The collected juice containing 85% of the total nitrogen content of soybeans was adjusted to pH 5.
, 5, mixed to facilitate precipitation and centrifuged in the same machine as above.

The residue is collected and dried by freezing.

1.55 kg of isolated protein are obtained in this way with 92.9% protein, ie 66% of the total nitrogen content of the soybean.

This isolated protein contains 0.61% phytic acid and 11n nitrogen.
96 units of trypsin inhibitor (K a
Measured by kade and coll, y, Cerea
l Chem, 51.

376.1974).

Its PER (protein effective ratio for casein standard with PER = 3.2) is 2.18, and its value is 1
After heat treatment for 0 minutes, it changes to 2.66.

For comparison, protein isolate produced under the same conditions with acidification to p) 14.5 yielded 2.26 kg of protein, i.e. 1.8% phytic acid and nitrogen representing 78% of the nitrogen content of the soybean. Contains 350 units of tryp**sin inhibitor (from Kakade and coll) per m9.

Its PER is only 1.66 and does not exceed 2.11 after heat treatment at 100°C for 10 minutes.

Commercially available isolated protein Promine R has a PER of 1.1
and 1.7 after heating under the above conditions.

Example 6 Soybean and peanut protein isolation (by precipitation) (a)
The preparation described in Example 4a was repeated.

However, defatted soybean flour (60 g) is suspended in a caustic soda aqueous medium with a final pH value of 12.0.

After removing the insoluble portion by centrifugation, half of the supernatant was adjusted to pH
Acidify to pH 4,5 and the other half to pH 5,5.

(b) The preparation of groundnut isolate protein as described in Example 4d is repeated at the above pH value conditions, namely 11.5.

After removing the insoluble portion by centrifugation, half of the supernatant was adjusted to pH
Acidify to pH 4,5 and the other half to pH 5,5.

For comparison, the trypsin inhibitor content of the soy protein isolate at pH 5.5 in Example 6a was 229 units, while the protein isolate prepared under the same conditions and precipitated at pH 4.5 had 375 units.

Example 7 Separation of soybean and peanut flour (by sedimentation) (a)
The preparation described in Example 4a was repeated.

However, the defatted soybean flour was suspended in an aqueous hydrochloric acid medium to obtain a pH value of 2.5.

After removing the insoluble portion by centrifugation, half of the supernatant was adjusted to pH
4,5 and the other half to I) H5,5.

(b) The preparation of groundnut isolate protein as described in Example 4d is repeated at the above pH value, ie 2.5.

After removing the insoluble portion by centrifugation, half of the supernatant was adjusted to pH
Acidify to pH 4,5 and the other half to pH 5,s.

For comparison, the trypsin inhibitor content of the soy protein isolate precipitated at pH 5.5 of Example 7a was
242 units compared to 443 units of the isolated protein precipitated in .

Example 8 Soy Protein Isolation (by Precipitation) The mode of practice of Example 6a is repeated on a larger scale with 10 kg of defatted soy flour suspended in a caustic soda aqueous medium with a final pH value of 11.5.

After removing the insoluble part, it contains 3.6 kg of protein and 0.
．． 4.0 kg of soybean protein isolate with a phytic acid content of 18% are obtained by precipitation at pH 5.5.

Example 9 Whole soybean isolated protein (by precipitation) 10 g of dehulled and ground whole soybean seeds are suspended in 190 g of water, and then the pH value of the suspension is adjusted to 8.0.

Insoluble material is then removed by centrifugation at 2000G for 10 minutes.

The fatty substances separated on the surface are added to the solution obtained after centrifugation, and the pH value of this solution is adjusted to 5.5.

The precipitate obtained (4 g after drying) had a protein content of 62% of the total dry matter, or approximately 83% of the non-fat dry matter, with a protein content of approximately 0.32%.
It is a protein isolate containing % phytic acid.

For comparison, 4.9 g of isolated protein containing 57% protein and 1.32% phytic acid in total dry matter are obtained by precipitation at pH 4.5.

Example 10 Round soybean concentrate protein Round soybean concentrate protein is made from 19 log dehulled and crushed whole soybean seeds.
It is prepared by suspending it in 0 g of water and then adjusting the pH value to 5.5.

The insoluble fraction is then separated by centrifugation for 10 min at 20'JOG, and the supernatant fatty material is added to the centrifuge sediment.

A whole soy protein concentrate (6 g) is thus obtained which, after drying, contains 51% protein in total dry matter, i.e. 68% non-fat dry matter and 0.31% phytic acid.

Claims (1)

[Scope of Claims] 1. A method characterized by separating plant-extracted proteins in solid form from an aqueous medium with a pH greater than 5.0 and 5.7 or less,
A method for producing plant-based protein extracts. 2. The method according to claim 1, wherein the plant extract protein is separated from the powder, isolate or concentrate. 3. Flours, isolates or concentrates are legume or oilseed flours;
The method according to claim 1 or 2, which is a isolate or a concentrate. 4. Powders, isolates or concentrates are flours of soybeans, sunflowers, corn, tanata beans, lima beans, castor beans, cotton, mustard, lupine, sesame, peanuts, cowpeas or Egyptian beans;
The method according to claim 1, 2 or 3, which is a isolate or a concentrate. 5. Suspend the plant powder in an alkaline aqueous medium with a pH of 7 to 14 or an acidic aqueous medium with a pH of 1 to 3.5, isolate the fraction that is easily soluble in these media, and prepare the plant extract with a pH of 5.0. ~5.7 (excluding 5,0) A method for producing a plant-extracted protein, characterized by precipitation and separation. 6. The method according to claim 5, wherein the plant extract protein is separated from the powder, isolate or concentrate. 1. Flours, isolates or concentrates are legume or oilseed flours,
7. The method according to claim 5 or 6, which is a isolate or a concentrate. 8. Flours, isolates or concentrates include soybean, sunflower, corn, chinese bean, lima bean, castor bean, cotton, bean, lupine, sesame, peanut, cowpea or Egyptian bean flour;
8. The method according to claim 5, 6, or 7, which is a isolate or a concentrate. 9. The method according to any one of claims 5 to 8, wherein the precipitation is carried out at a pH of 5.3 to 5.5. 10 The pH of the aqueous medium is adjusted using hydrochloric or phosphoric acid, acetate or carbonate buffers or sodium hydroxide or potassium hydroxide solutions, claims 5 to 9.
The method described in any one of paragraphs.