Response surface optimization of the formula of composite biological preservative for squid

LIU Xue-fei; LIU Xin-mei; ZHAO Dong-yu; ZHANG De-fu; BAI Feng-ling; MOU Wei-li; SHEN Lin; LI Jian-rong

doi:10.3969/j.issn.1673-0569.2017.04.006

Abstract：To avoid corruption and prolong the shelf -life of squid , spoilage bacteria from squid was used as indicator bacteria to study the antibacterial properties of Chinese prickly ash , aniseed , pepper , chitosan and pro-tamine .In order to screen the best formula of composite bio -preservative for squid , the preservatives with better antibacterial properties was selected to carry out the response surface optimization tests and the plate verification experiment .The results show that aniseed , chitosan and protamine had better antibacterial effects on spoilage bacteria of squid , chinese prickly ash and pepper had little inhibitory effects on squid spoilage bacteria .The minimum inhibitory concentration ( MIC) of chitosan and protamine against spoilage bacteria of squid was respec-tively 4.8 mg/mL and 2.4 mg/mL with the two-fold dilution method.Primary and secondary order of 3 pre-servatives with better inhibition effect on squid spoilage bacteria was protamine >chitosan >aniseed .Prota-mine and chitosan dosage had a very significant effect on the antibacterial properties of composite bio -preserva-tive (P<0.01), aniseed dosage has no obvious influence (P>0.05).The optimum formula of composite bio -preservative was protamine 2.39 mg/mL, chitosan 4.8 mg/mL and aniseed 100 mg/mL.The result of plate verifi-cation experiment showed that the inhibitory zone of the same amount of composite bio -preservative was 96.75％of the predicted value of the model , indicating that the model obtained could predict the inhibitory effect of com-posite bio-preservative on squid spoilage bacteria .