Soy protein isolate is made from soy meal with moisture, fats and carbohydrates removed. Its protein content is 90%, the highest among all other soy products like textured soy flour and soy concentrate. Due to the low fats and carbohydrate content, the taste of soy protein isolate is milder and more neutral than the normal soy flour. It is widely consumed and utilised in the food industry as it caters to people who are lactose intolerant and is gluten free. Besides possessing the health benefits offered by all soy products, it also reduces flatulence, a symptom that is common from consuming other soy products.
Soybeans are first grinded into powder to form soy flour. After which, it is dehydrated at pH 9 and below. In doing so, the insoluble solids are also removed. The supernatant liquid is then acidified to pH 4-5. Protein curd is then precipitated, and separated by centrifuging the supernatant liquid. The curd is then neutralised with alkali before drying to form soy protein isolate.
Soy protein isolate can also be lecithinated to increase the nutritional value.
Soya protein isolate is widely used in the food industry. It is commonly used as emulsifiers in food products and is often added into meat products for better texture.
Due to its mild and neutral taste, soy protein isolate is added into food products like bread, infant formula milk and beverages as supplement to increase the nutritional value without altering the taste of the food products.
It is also popularly incorporated into gluten free diet and serves as a good alternative for people with lactose intolerance.