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Lipids from cephalothorax of Pacific white shrimp (Litopenaeus vannamei) are obtained using solvent extraction and ultrasonic assisted extraction (UAE). Among all solvents used, the mixture of hexane:isopropane (1:1) provided the highest yield (25.32% dry weight basis) and carotenoid content (1.97 mg g−1 lipid). When ultrasonication with different amplitudes (50–90%) is used for 25 min, the highest yield is obtained at 80% amplitude (p < 0.05). With the same ultrasonication time, UAE with continuous mode rendered the higher yield than pulse mode (p < 0.05). Lipid extracted with hexane:isopropanol mixture with UAE process has the yield of 49.81%. Phospholipids are major constituents of lipids extracted by solvent extraction. However, more free fatty acids, mono, and diglycerides are found in lipids extracted by UAE process, indicating increased hydrolysis. UAE process resulted in higher oxidation of lipids as evidenced by increased peroxide values (PVs) and thiobarbituric acid reactive substances (TBARS). Those alterations are more pronounced in lipids extracted using UAE with continuous mode than pulse mode as confirmed by fourier transform infrared (FTIR) spectra. Overall, UAE process markedly increased the yield of lipids from shrimp cephalothorax, but oxidation and hydrolysis took place to some degree. Practical Applications: Cephalothorax of Pacific white shrimp contains high value products, especially lipids rich in polyunsaturated fatty acids (PUFAs) and astaxanthin. These value‐added products can serve as excellent source of nutrients as well as bioactive compounds with proven health benefits. The extraction yield of lipid and carotenoid are significantly higher when UAE was implemented, compared to the conventional solvent extraction method. The lipids extracted by UAE process are found to have high free fatty acids (FFAs). The lipids rich in FFAs can be used as alternative raw material for manufacturing of biodiesel or other marketable products. Lipids from cephalothorax of Pacific white shrimp (Litopenaeus vannamei) are obtained using solvent extraction and ultrasonic assisted extraction (UAE). Different solvents are used to investigate for the highest yield and a mixture of hexane:isopropanol (1:1) provided the highest yield of 25.32% (db). Ultrasonication with different amplitudes (50–90%) is used for 25 min and the highest yield is obtained at 80% amplitude with continuous mode.

Impacts of pulsed electric field (PEF) pretreatment with different electric field strengths (4, 8, 12 and 16 kVcm-1 ) and pulse numbers (120, 160, 200 and 240) on extraction yield of lipid and cell disintegration index (Zc) of Pacific white shrimp cephalothorax were examined. PEF treated samples were subsequently subjected to lipid extraction using ultrasonic assisted extraction (UAE) process at ultrasonic amplitude of 91.2 microns for 25 min in continuous mode. Samples with PEF pretreatment and subjected to UAE rendered the highest lipid yield (30.34% dry basis). PEF pretreatment resulted in suppression of lipid oxidation as affirmed by the decreases in peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). Lipid from PEF pretreated samples had higher content of PUFAs as well as carotenoids, which included astaxanthin, astaxanthin monoester, astaxanthin diester, canthaxanthin and β-carotene. Overall, PEF was a promising pretreatment to increase the yield and maintain the quality of lipid extracted from cephalothorax using UAE.

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