Effect of citric acid on the quality and shelflife of dried shrimp
1996
Yaowalux Ruttanapornvareesakul
Dried shrimp was processed by dipping fresh shrimp in 0.1, 0.3, 0.5 percent citric acid solution then boiling in 5 percent brine to select appropriate concentration of citric acid. Shelflife storage of dried shrimp under vacuum and air packed at 30+-2 deg C and 10+-2 deg C was studied. Chemical (astaxanthin, ammonia, moisture, NaCl, pH), microbiological (TVC, anaerobe TVC, yeast and mold, E. coli, S. aureus, Salmonella, Vibrio), physical (Aw, colour using L, a, b system) analysis and sensory evaluation were conducted. It was found that astaxanthin content and overall acceptability of samples dipped in 0.1, 0.3, 0.5 percent citric acid solution were not significantly different (P0.05) but they were significantly better than samples without citric acid dipping. Therefore the lowest concentration of citric acid solution, 0.1 percent was selected for studing the changes of quality during storage under vacuum and air packed. The results had shown that dried shrimp under all conditions of packaging stored at 10+-2 deg C had shelflife longer than 14 weeks, and had better quality than samples stored at 30+-2 deg C. Sample stored under air packed and vacuum at 30+-2 deg C had shelflife of 6 and 8 weeks, respectively, Moreover dried shrimp dipped in citric acid solution had better colour, higher astaxanthin content and higher acceptability score as well as lower ammonia content than samples without citric acid dipping (P0.01) both stored under vacuum and air packed at 30+-2 deg C and 10+-2 deg C.
显示更多 [+] 显示较少 [-]