EFFECT OF EVAPORATED ETHYL PYRUVATE ON SOME CHARACTERISTICS OF SHRIMPS (PARAPENAEUS LONGIROSTRIS) DURING REFRIGERATED STORAGE

Abstract

In the study, effect of ethyl pyruvate (EP), which has more likely been the topic of medical research, on certain characteristics of shrimps was investigated with EP being applied in the vapor-phase as an alternative antimicrobial agent. For this purpose, freshly supplied shrimps were allocated into five groups. The first group was treated with sodium metabisulphite (Na2S2O5) within permissible limits while the other groups were processed with 42, 105, 260 and 420 mg/L of EP, respectively. Then the shrimps were stored in a refrigerator for five days and daily exposed to microbiological (total aerobic mesophilic bacterial count, total psychrophilic bacterial count and Pseudomonas spp. count) and physicochemical (pH, water activity, total volatile basic nitrogen, trimethyl amine) analyses. Sensory analyses were carried out on the first and second days of the storage. While high concentration of EP was found to be effective on inhibiting microbial growth, its low concentrations rather aided in maintenance of physicochemical parameters at desired levels. Sensory panel revealed a spicy, palatable flavor in the shrimps treated with medium level concentration (105 mg/L) of EP. It was concluded that EP might have been used as an alternative microbiologic agent in the refrigerated storage of shrimps; however further studies should be carried out on the subject.