Impact of high-pressure processing on hemolymph, color, lipid globular structure and oxidation of the edible portion of blood clams

Abstract

Impact of high-pressure processing (HP-P) on hemolymph and lipid globular structures of the edible portion (EP) of blood clams (BC) was investigated. HP-P above 400 MPa decreased heme iron content, while upsurged non-heme iron content. Increasing pressure induced gaps and abnormal hemocyte cell arrangements. However, HP-P at 300 MPa improved and maintained total hemocyte counts, the heme iron content, and a*-value in BC-EP. For lipid globular structures, the mean diameter drastically decreased when an HP-P pressure of 600 MPa was employed. HP-P at higher pressure induced lipid oxidation, along with decreases in monounsaturated and polyunsaturated fatty acids as well as increases in thiobarbituric acid reactive substances and peroxide value. FTIR spectra displayed a reduction in phosphate groups and cis double bonds in lipids from HP-P treated BC, compared to controls. Therefore, HP-P at 300 MPa is recommended for preparing ready-to-cook BC with less tissue damage and lipid oxidation.

Keywords: Blood clam; Hemoglobin; High-pressure processing; Histological analysis; Ready-to-cook product.