Production of low salted and fermented shrimp by irradiation

Abstract

Shrimp (Acetes chinensis) were sliced, washed, and then salted with 15 and 20% (w/w) sodium chloride. Salted shrimp was 0, 5, and 10 kGy-irradiated at 2 different stages: 1) irradiated immediately after processing salted shrimp, 2) irradiated at optimum fermentation period, and fermented at 15 degreesC for 10 weeks. Nonirradiated shrimp with 30% salt were also prepared as a control. Irradiated shrimp were not different in proximate composition, salinity, and water activity from nonirradiated shrimp with the same salt addition and the same irradiation time. During fermentation, volatile basic nitrogen (VBN) contents increased as the salt concentration and irradiation dose decreased. From results of sensory analysis, total bacterial count, and pH, the combination of low salt concentration (15% or 20%) and gamma irradiation (5 or 10 kGy) was effective in processing low-salted and fermented shrimp. Results provided no adverse sensory quality and improved microbial shelf-stability compared to control (30% of salt addition).