Soy protein isolate is a full-value protein food additive produced from low-temperature solubilized soybean meal. The protein content of soybean protein isolate is more than 90%, there are nearly 20 kinds of amino acids, and it contains essential amino acids for human body. It is nutritious and cholesterol-free, making it one of the few plant-based alternatives to animal protein.

Soybean protein is a high molecular organic polymer composed of a series of amino acids through peptide bonds. It is mainly composed of albumin and globulin, of which albumin accounts for about 5% and globulin accounts for about 90%.

There are two classification methods for the existence of soybean protein isolate, one is the classification method according to the sedimentation index. After high-speed centrifugation, soybean protein is divided into 4 grades: 2S, 7S, 11S, and 15S according to the centrifugal sedimentation index. Among them, 7S and 11S are the main components, and they are also the main components of globulin, accounting for about 70% of the total protein. The functional properties of soy protein isolate play a very important and leading role. The other is a taxonomy based on immunological properties. It can be divided into a-concentrated globulin (about 15%), 13-concentrated globulin (about 28%), concentrated globulin (about 3%), soluble globulin (about 40%) 4 kind.

Application

Functional characteristics

Soy protein isolate is a surfactant that reduces the surface tension of water and oil, as well as water and air. Easy to form stable emulsions. In the production of baked food, frozen food and soup food, adding soy protein isolate as an emulsifier can stabilize the state of the product.

Hydration

Along its peptide chain backbone, soybean protein isolate contains many polar groups, so it has water absorption, water retention and swelling properties. The water absorption of protein isolate is much stronger than that of concentrated protein, and it is almost not affected by temperature. It also has the ability to retain moisture during processing, with a maximum moisture retention capacity of 14g water/g protein.

Oil absorption

The addition of protein isolates to meat products can form an emulsion and gel matrix to prevent fat from moving to the surface, thus promoting fat absorption or fat binding, reducing the loss of fat and juice during meat processing, helping to maintain The shape is stable, and the oil absorption rate of the isolated protein is 154%.

Gelatinous

 It makes the isolated protein have high viscosity, plasticity and elasticity, and can be used as a carrier for water, as well as a carrier for flavors, sugars and other complexes, which is extremely beneficial to food processing.

Foaming

Among soy proteins, protein isolates have the best foaming properties. Using the foaming properties of soybean proteins, food can be given a loose structure and good taste.

Conjunctival

 When the meat is minced, it is coated on its fiber surface with a mixture of isolated protein and egg protein to form a film that is easy to dry, prevents odor loss, facilitates the rehydration process, and provides a reasonable structure to the rehydrated product.

Application

meat products

Adding soybean protein isolate to high-grade meat products not only improves the texture and flavor of meat products, but also increases the protein content and strengthens vitamins. Due to its strong functionality, the dosage of 2~5% can play the role of water retention, fat retention, preventing gravy segregation, improving quality and improving taste. After processing the meat, the percentage of ham can be increased by 20%. Sausages, hot dog sausages, meat skewers, Sichuan-flavored chicken fillets, flesh-and-bone, Colonel chicken nuggets, McNuggets, Orleans roast duck embryos, seasoned wings, marinated pipa legs, luncheon meat, sandwiches and other meat products are processed in, soybean protein isolate The addition of soy protein can make the structure of the product more perfect, and the soy protein isolate and the vegetarian meat powder of Bangui can be added at the same time. Nutrition is more scientific.

Surimi products

Isolated protein is used in fried fish cakes, fish, tofu, fish steak, fish plate, fish roll, conch ball, northern sea fin, crab steak, crab stick, scallop, grilled sausage, shrimp flavored sausage, abalone sausage, sea cucumber, hot pot sausage, fish sausage, and fish rice cracker. It is advisable to take 20~40% of the fish.

Dairy products

Soy protein isolate is used to replace milk powder, non-dairy beverages and various forms of milk products. Nutritious and cholesterol-free, it is an alternative to milk. Soy protein isolate can be used in ice cream production instead of skim milk powder, which can improve the emulsification properties of ice cream, delay the crystallization of lactose, and prevent the phenomenon of "sand".

Pasta

Adding no more than 5% protein isolate when producing bread can increase the volume of bread, improve skin color and prolong shelf life; adding 2~3% protein isolate when processing noodles can reduce the breakage rate after boiling and improve noodles. The yield is good, and the color of the noodles is good, and the taste is similar to that of strong flour noodles.

Soy protein isolate can also be used in beverages, nutritional foods, fermented foods and other food industries. It has a unique effect on improving food quality, increasing nutrition, reducing serum cholesterol, and preventing heart and cerebrovascular diseases.