不同介质中甲型副伤寒沙门氏菌的热失活特性

摘要

This study aimed to study the thermal inactivation profile of Salmonella paratyphi A in different media.Salmonella paratyphi A was inoculated at a concentration of 108 CFU/g into different media,and then subjected to thermal treatments at different temperatures.The surviving cells were counted on selective media.DoseResp model was used to fit the thermal inactivation curve by Origin 8.0 software.The decimal reduction time (D) values were calculated,which represented the heat resistance of Salmonella paratyphi A.The results showed that thermal inactivation curves were well fitted to the DoseResp with a correlation coefficient (R2) ＞ 0.97.The D values of Salmonella paratyphi A in different media were different.The D value in sausage high in fat and protein with a lean meat-to-fat ratio of 1∶1 (m/m) was greater,indicating that that it was relatively heat resistant.Salmonella paratyphi A could be killed by thermal treated at 55 ℃ for 25.0 min,63 ℃ for 2.03 min,or 72 ℃ for 0.31 min in common meat products.%研究甲型副伤寒沙门氏菌在不同介质中热失活规律,对接种108 CFU/g甲型副伤寒沙门氏菌的不同介质进行55、63、72℃热处理,测定处理后样品中甲型副伤寒沙门氏菌的菌体浓度.应用DoseResp模型拟合在3种温度下志贺氏菌的动力学模型,用D值(decimal reduction time)表示甲型副伤寒沙门氏菌在不同介质中的耐热情况.结果表明:甲型副伤寒沙门氏菌的热失活曲线运用DoseResp模型拟合较好,相关系数均在0.97以上.甲型副伤寒沙门氏菌在不同介质中的D值不同,在蛋白质和脂肪含量较高的灌肠肥瘦肉1∶1 (m/m)中D值较大,相对耐热.55℃条件下热处理25.0 min,63℃热处理2.03 rmin,72℃热处理0.31 min后,一般肉制品中甲型副伤寒沙门氏菌均能被杀死.