Soaking changes the moisture and chemical composition of the peas, and the fiber absorbs water and expands, making it easy to separate from the protein starch after being broken, so that the protein and starch can be easily extracted from it.
The effect of soaking time on the yield of protein and starch.
If the time is too long, the raw materials are easy to deteriorate, and the protein and starch are not easy to separate. Moreover, the container utilization rate is low, which is economically unreasonable; if the time is too short, the peas have not been completely softened, the power consumption during refining increases, and the network structure of the fiber and protein in the peas is not easily destroyed, and the starch particles are contained in the structural network. It is difficult to extract and separate the pigments and colloidal substances, and the purity of the obtained product is reduced. We soak peas for different times, compare the yield and quality of their protein and starch, to determine a better soaking time range.
2. Smash and Sieving
Smashing is to destroy the internal fiber and protein structural network of pea through mechanical action. So that starch and protein are dissolved in the refining liquid to achieve the purpose of separation and extraction.
Theoretically, the number of pea milling times is directly proportional to the product yield. In our research, we found that the secondary refining effect is the best.
After refining, the crude fiber is separated from the slurry containing starch and protein, that is, the residue is separated. If the sieve of the sample sieve is too large during slag separation, some of the finely ground fibers and impurities will pass through the sieve along with the slurry, and the purpose of slag separation will not be achieved; if the sieve is too small, a part of the swollen large protein particles cannot pass through the screen, which reduces the output. Refer to the relevant information, Hua-Thai chooses 100 mesh sieve to get the best effect.
3. Sieve and Separate
Starch has the characteristics of retrogradation, and choosing an appropriate resting time is also a technological requirement. The separation of starch requires that the starch be fully retrograded before the protein precipitates to achieve the purpose of separating starch and protein.
4. Centrifugal Settlement
The centrifugal force generated by the centrifuge can be much greater than gravity, so the speed of centrifugal sedimentation is much greater than that of natural sedimentation. Centrifugal sedimentation is used to shorten the sedimentation time.
The separated starch can be dried in an electric thermostat, but the temperature should not be too high at the beginning, because in the presence of more free water, high temperature will gelatinize the starch, thereby destroying its color and functional characteristics. Hua-Thai uses a pulsed air dryer when drying the protein. The inlet air temperature: 150-180°C, the exhaust air temperature: 40-60°C, and the transmission speed 30-50Hz.
Pea protein is one of the important sources of protein. Its amino acid ratio is relatively balanced. Except for the low content of methionine, the eight essential amino acids for the human body have reached the recommended model values of FAO/WHO. At the same time, it also has many excellent functional properties, such as solubility, gel formation, emulsifying power and good heat and salt resistance. Therefore, it has good application potential and a broad market.Hydrolyzed Pea Protein