Effects of high-pressure processing on the quality of chopped raw octopus

This study evaluated the effects of high-pressure treatment on microbial growth and production of off-flavor compounds in raw octopus during 16 days of refrigerated storage. Chopped raw octopus samples were treated at 150, 300, 450, and 600 MPa for 6 mm using high-pressure laboratory food processing equipment. The number of psychrotrophic bacteria on day 16 was reduced by 0.1, 0.5, 1.3, and 2.8 CFU/g after pressure treatment at 150, 300, 450, and 600 MPa, respectively, as compared with control group. The amounts of trimethylamine (TMA) and dimethylamine (DMA) produced in the chopped raw octopus treated at 600 MPa was significantly reduced by 42.5% and 62.2%, respectively, as compared to the levels in the control. The production of biogenic amines (BAs) increased up to 1.82 mg/g in the control after 12 days of refrigerated storage, while the BA levels in the 450 MPa- and 600 MPa-treated octopus were 1.40 and 1.35 mg/g, respectively. Thus, high-pressure treatment effectively inhibited microbial growth and suppressed the formation of off-flavor compounds in raw octopus. High-pressure treatment is a promising alternative technology for extending the shelf life of raw octopus. (C) 2013 Elsevier Ltd. All rights reserved.