Comparison of different solvents for extraction of oils from by-products of shrimps Penaeus vannamei and Procambarus clarkia

The effects of different extraction solvents on the extraction yield and chemical composition of oils from by-products of marine shrimp Penaeus vannamei ( Pv ) and freshwater shrimp Procambarus clarkia ( Pc ) were investigated. Our results indicated that the ethanol and n-hexane mixture (4:1, v/v) was suitable solvent for simultaneous extraction of phospholipid and nonpolar lipids. By contrast, the ethanol and n-hexane mixture (4:1, v/v) and single ethanol were suitable solvents for the extraction of polyunsaturated fatty acids-rich (36.10%–42.78% of total fatty acids for Pv and 23.57%–25.58% of total fatty acids for Pc ) and phosphatidylcholine-rich (66.22–67.09 mol% of total phospholipids for Pv and 55.01–58.68 mol% of total phospholipids for Pc ) oils, but acetone was suitable solvent for the extraction of astaxanthin-rich oil (436.19 μg/g oil for Pv and 799.27 μg/g oil for Pc ). The findings will provide relevant information that can be used to improve the production of nutritional oils from shrimp by-products. Practical applications This study provides a theoretical basis for creating proper extraction processing to recover nutritional oils from shrimp by-products. For example, the ethanol and n-hexane mixture (4:1, v/v) was a suitable solvent for simultaneous extraction of phospholipid and non-polar lipids. By contrast, both of the ethanol and n-hexane mixture (4:1, v/v) and single ethanol were suitable solvents for the extraction of polyunsaturated fatty acids (PUFA)-rich and phosphatidylcholine-rich oils, but acetone was a suitable solvent for the extraction of astaxanthin-rich oil. Therefore, the oils extracted from shrimp by-products are rich in phospholipid, PUFA, and astaxanthin, which may be used as new functional food ingredients.