Goepfert J M, Iskander I K, Amundson C H
Appl Microbiol. 1970 Mar;19(3):429-33. doi: 10.1128/am.19.3.429-433.1970.
The effect of water activity (a(w)) on the heat resistance of eight strains of Salmonella was studied. Heat resistance of the organisms increased as the a(w) of the heating menstruum was reduced. Sucrose afforded the cells a greater degree of protection than did fructose, glycerol, and sorbitol. A direct correlation between a(w) and heat resistance could not be established over the range of a(w) levels tested in this study. There was variation among the strains of salmonellae in the magnitude of the increase in heat resistance as the a(w) level was reduced. All strains of Salmonella tested showed a greater increase in heat resistance than S. senftenberg 775W as the environment became drier. Washed cells had D values 25 to 75% lower than unwashed cells. Prior growth of the organisms in media with a reduced a(w) increased the heat resistance of the organisms when glycerol, but not when sucrose, was the controlling substance.
研究了水分活度(a(w))对8株沙门氏菌耐热性的影响。随着加热介质水分活度的降低,这些微生物的耐热性增强。与果糖、甘油和山梨醇相比,蔗糖为细胞提供了更高程度的保护。在本研究测试的水分活度水平范围内,无法建立水分活度与耐热性之间的直接相关性。随着水分活度水平的降低,沙门氏菌各菌株耐热性增加的幅度存在差异。当环境变得更干燥时,所有测试的沙门氏菌菌株的耐热性增加幅度均大于肠炎沙门氏菌775W。洗涤后的细胞D值比未洗涤的细胞低25%至75%。当甘油(而非蔗糖)作为控制物质时,微生物在水分活度降低的培养基中预先生长会提高其耐热性。