Sorrells Kent M, Enigl Davin C, Hatfield John R
Research and Development Microbiology, Beatrice/Hunt-Wesson, Inc., Fullerton, California 92634.
J Food Prot. 1989 Aug;52(8):571-573. doi: 10.4315/0362-028X-52.8.571.
The effect of different acids, pH, incubation time, and incubation temperature on the growth and survival of four strains of Listeria monocytogenes in tryptic soy broth was compared. Hydrochloric acid (HCl), acetic acid (AA), lactic acid (LA), malic acid (MA), and citric acid (CA) were used to acidify tryptic soy broth to pH values 4.4, 4.6, 4.8, 5.0, and 5.2 pH. Incubation times were 1, 3, 7, 14, and 28 d at 10, 25, and 35°C. The inhibition of L. monocytogenes in the presence of high acidity appears to be a function of acid and incubation temperature. Based on equal pH values, the antimicrobial activity is AA > LA > CA ≥ MA > HCl at all incubation times and temperatures. When based on equal molar concentration, the activity appeared to be CA ≥ MA > LA ≥ AA > HCl at 35 and 25°C, and MA > CA > AA ≥ LA > HCl at 10°C. Greatest antimicrobial activity occurred at 35°C. Greatest survival occurred at 10°C and greatest growth occurred at 25°C. Final pH of the medium was as low as 3.8 in HCl at 28 d. All strains grew well at pH values lower than the minimum previously reported (5.5-5.6).
比较了不同的酸、pH值、孵育时间和孵育温度对胰蛋白胨大豆肉汤中4株单核细胞增生李斯特菌生长和存活的影响。使用盐酸（HCl）、乙酸（AA）、乳酸（LA）、苹果酸（MA）和柠檬酸（CA）将胰蛋白胨大豆肉汤酸化至pH值4.4、4.6、4.8、5.0和5.2。在10、25和35℃下孵育时间分别为1、3、7、14和28天。在高酸度条件下对单核细胞增生李斯特菌的抑制作用似乎是酸和孵育温度的函数。基于相同的pH值，在所有孵育时间和温度下，抗菌活性为AA > LA > CA ≥ MA > HCl。基于相同的摩尔浓度，在35℃和25℃时活性似乎为CA ≥ MA > LA ≥ AA > HCl，在10℃时为MA > CA > AA ≥ LA > HCl。最大抗菌活性出现在35℃。最大存活率出现在10℃，最大生长率出现在25℃。在28天时，HCl处理的培养基最终pH值低至3.8。所有菌株在低于先前报道的最低pH值（5.5 - 5.6）时均生长良好。
