sunflower seed protein is also called sunflower protein. It is a protein product made from defatted sunflower seed cake, after removing the shell and phenolic acid compounds such as chlorogenic acid and caffeic acid. The main components are globulin (about 70% to 79%), followed by albumin and a small amount of gluten and alcohol-soluble protein. In the amino acid composition, the lysine content is low, while the content of other essential amino acids is high.
Protein Composition
Domestic sunflower kernels contain 21% to 30% protein, and sunflower seed cake after oil extraction generally contains more than 50% protein. The globulin content in sunflower seed protein is 55% to 60%, albumin is 17% to 23%, alcohol-soluble protein is 1% to 4%, and gluten is 11% to 17%. The bound non-protein nitrogen and insoluble residues are less than 11% of the total nitrogen content. The solubility of sunflower seed protein in aqueous solution, salt solution and ethanol solution is 20%, 50% to 60% and 3% respectively. Using gel chromatography, ultrafiltration, electrophoresis and other methods to qualitatively find that the molecular weight of sunflower seed protein ranges from 10 to 450 kDa, the molecular weight of the main component is 125 kDa, and the average molecular weight is 180 kDa. It contains 6 to 7 protein components. Studies have found that sunflower seed protein is mainly composed of two components, 7 to 8S and 11 to 12S. The isoelectric point of sunflower seed protein is pH 4.0.
Nutritional Characteristics
Depending on the variety and growth environment, the chemical composition of sunflower seeds will have certain differences. Domestic sunflower kernels usually have a fat content of 40% to 68%, a protein content of 21% to 30%, a carbohydrate content of 2.0% to 6.5%, a crude fiber content of 6.0%, and an ash content of 3.2% to 5.4%. After extracting oil, the sunflower seed cake generally contains 29% to 43% crude protein, 4% to 15% crude fat, 7% to 23% cellulose, 3% to 19% moisture, and 7% to 10% ash.
In the composition of amino acids in sunflower seed protein, the content of lysine is higher than that of cereal protein, but slightly lower than that of soy protein and animal protein. The other various amino acids have a good balance. Its amino acid composition is compared with the FAO value. Except for the lysine content, the contents of other essential amino acids are higher than or similar to the FAO value, so lysine is the first limiting amino acid in sunflower seeds. Although the lysine content is low, its effective lysine content can be as high as 90%. Sunflower seed protein is rich in sulfur-containing amino acids such as methionine. Compared with most plant proteins, sunflower seed protein has good digestibility (90%) and higher biological value (60%).
Contact Now
