复配抑菌剂对单增李斯特菌的抑制作用及其保鲜效果

Inhibition and preservation effect of compound antibacterial agent on Listeria monocytogenes

研究溶菌酶、甘氨酸和乙酸钠对单增李斯特菌的抑制效果,通过单因素抑菌率的结果,运用响应面法优化三种抑菌剂复配后对单增李斯特菌的抑制效果,并且将得到的最优浓度复配抑菌剂用来保鲜感染了单增李斯特菌的三文鱼,以细菌总数、单增李斯特菌数、pH、TBA值和TVB-N值为指标,研究复配抑菌剂的保鲜效果。结果表明:溶菌酶0.6 g/L、甘氨酸浓度为6.4 g/L、乙酸钠浓度为4.9 g/L为复合保鲜剂的最佳配比,此条件下对单增李斯特菌的抑菌率为80%±0.23%。冷藏条件下,经复配抑菌剂处理后的三文鱼品质优于未经处理的空白组,第7 d时,实验组细菌总数、单增李斯特菌数、pH、TBA值和TVB-N值分别为5.56 lg CFU/g、4.65 lg CFU/g、6.78、1.048 mg MDA/kg、18.03 mg N/100 g,相比空白组,能延长2 d的货架期。

To study the combined effect of lysozyme, glycine and sodium acetate on Listeria monocytogenes.The response surface methodology was used to determine the optimal combination of antibacterial agents.The effects of the calculated combinations of antibacterial agents were evaluated on the preservation of raw salmon. The bacterial count, pH, 2- thiobarbituric acid （TBA） content and total volatile basic nitrogen （TVB-N）content were measured to determine the changes in the quality of salmon during cold storage.The results showed that the optimal concentrations of lysozyme, glycine and sodium acetate were 0.6,6.4 and 4.9 g/L, the inhibition rate was 80% ± 0.23% .The compound bacterial agent group＇ s bacterial count, pH, TBA contents and TVB-N was 5.56 lg CFU/g,4.65 lg CFU/g,6.78,1.048 mg MDA/kg, 18.03 mg N/100 g in the seventh day.These indicators were much lower in the compound bacterial agent group than in the control, and the sensory scores were higher for raw salmon treated with the compound bacterial agent than for the control.This compound bacterial agent may effectively extend the shelf life of raw salmon by approximately two days.