Alkaline Extraction Method of Cottonseed Protein Isolate

Cottonseed protein was extracted from defatted cottonseed flour with alkaline solvent and its precipitation property in different pH value was investigated. Orthogonal experiments design was introduced and factors influencing protein extraction were studied, namely, extraction solvent type, solvent-to-flour ratio, extraction pH value, extraction temperature and time. The optimum scheme of extraction was obtained: 0.1N KOH as extraction solvent, solvent-to-flour ratio=12,pH=12.5, temperature=60? and time=40min.Under this condition, the cotton protein extractability is above 70%and the protein extraction can be directly applied to further chemical modification.