Nutrición y Bromatología, Escuela de Ingenierías Agrarias, Universidad de Extremadura, Avd. Adolfo Suárez s/n, 06007 Badajoz, Spain; Instituto Universitario de Investigación en Recursos Agrarios, Avd. De la Investigación, Universidad de Extremadura, 06006 Badajoz, Spain.
Nutrición y Bromatología, Escuela de Ingenierías Agrarias, Universidad de Extremadura, Avd. Adolfo Suárez s/n, 06007 Badajoz, Spain; Instituto Universitario de Investigación en Recursos Agrarios, Avd. De la Investigación, Universidad de Extremadura, 06006 Badajoz, Spain.
J Dairy Sci. 2017 Sep;100(9):6987-6996. doi: 10.3168/jds.2017-12865. Epub 2017 Jul 12.
Traditional cheeses may be contaminated by aflatoxin-producing Aspergillus flavus during the ripening process, which has not been sufficiently taken into account. The objectives of this study were to evaluate the influence of water activity (a), pH, and temperature on the lag phases, growth, and aflatoxin production of 3 A. flavus strains (CQ7, CQ8, and CG103) on a cheese-based medium. The results showed that the behavior of A. flavus strains was influenced by pH, a, and temperature conditions. The CQ7 strain showed the maximum growth at pH 5.5, 0.99 a, and 25°C, whereas for CQ8 and CQ103 strains, no differences were obtained at pH 5.5 and 6.0. In general, low pH, a, and temperature values increased the latency times and decreased the growth rate and colony diameter, although a and temperature were the most limiting factors. Maximum aflatoxin production on the cheese-based medium occurred at pH 5.0, 0.95 a, and 25 or 30°C, depending on the strain. This study shows the effect of pH, a, and temperature factors on growth and aflatoxin production of 3 aflatoxigenic A. flavus strains on a cheese-based medium. The findings may help to design control strategies during the cheesemaking process and storage, to prevent and avoid aflatoxin contamination by aflatoxigenic molds.
传统奶酪在成熟过程中可能会被产黄曲霉毒素的黄曲霉菌污染，但这一点尚未得到充分考虑。本研究的目的是评估水分活度（a）、pH 值和温度对 3 株黄曲霉菌（CQ7、CQ8 和 CG103）在奶酪基培养基上的延滞期、生长和黄曲霉毒素产生的影响。结果表明，黄曲霉菌株的行为受到 pH 值、a 和温度条件的影响。CQ7 菌株在 pH5.5、0.99a 和 25°C 时表现出最大生长，而 CQ8 和 CQ103 菌株在 pH5.5 和 6.0 时没有差异。一般来说，低 pH 值、a 和温度值会增加潜伏期，降低生长速率和菌落直径，但 a 和温度是最具限制的因素。3 株产黄曲霉毒素的黄曲霉菌在奶酪基培养基上的最大产毒量发生在 pH5.0、0.95a 和 25 或 30°C，具体取决于菌株。本研究表明了 pH 值、a 和温度因素对 3 株产黄曲霉毒素的黄曲霉菌在奶酪基培养基上的生长和黄曲霉毒素产生的影响。这些发现可能有助于在奶酪制作过程和储存过程中设计控制策略，以防止和避免产黄曲霉毒素的霉菌对黄曲霉毒素的污染。
