Soy (Soybean) Protein is the protein obtained from Soybeans, containing the essential amino acids.
Since the approval of soy protein isolate and concentrate in Canada, usage has steadily increased. Soy is not used as a meat replacer but as a protein extender, emulsifier and binder in emulsion and whole muscle products.
After the oil is extracted from the beans, the resulting product is dried and finely ground. It is used as a protein additive in pet foods and health foods but the beany flavour persists. Soy flour has a protein content of 50%.
Textured Soy Protein
Good quality soy flour, soy concentrate or soy isolate is mixed with water into a dough, extruded under moist heat and high pressure, to form chips or chunks of flakes. The granules or textured pieces have 50- 90% protein and a better flavour than soy flour due to the heat process of extrusion. They are added to fresh ground meat products as an extender and have a similar meat like texture when hydrated (1:2-3).
Textured soy will bind free fat and water, improve texture and reduce flaring on grills.
Soy Protein Concentrates
Soy Protein Concentrate has a protein of 68-70% and is usually used in fine emulsion and ground meat products. It has a very low flavor profile and high protein solubility. For fine emulsion sausage 1 – 2 % soy concentrate will bind fat, extend the formula and reduce cooking shrink.
Granules of soy protein concentrate are used to improve the texture of ground meat products such as burgers and fresh sausage. They are usually used at 2 – 3 % and are rehydrated at 1 part soy to 3 parts water, prior to addition to meat batch.
Soy concentrate is usually used in conjunction with other binding systems such as starches and flours.
Soy Protein Isolate
Soy protein isolates contain approximately 90% protein and generally have a lower flavour profile than soy protein concentrates. Isolates contain a high percentage of soluble protein and are used for fat emulsification, water binding and protein additives for injection systems where permitted.
The soy protein isolate we carry is nitrite free and can be pumped into roast beef and poultry products with none of the pinking associated with sodium nitrite. Isolate are currently being used with great success in roast beef to reduce the drip loss out of the tumbler and reduce the shrink in the smokehouse.
Soy protein isolate is virtually fat and carbohydrate free, and are therefore desirable for making low fat meat products.