This study aimed at evaluating the physicochemical and microbiological quality, besides the occurrence of aflatoxins M₁ and B₁, in samples (229) of the whole, semi‐skimmed and skimmed milk processed by the ultra‐high‐temperature system, in the three Brazilian southern states (Rio Grande do Sul, Santa Catarina and Paraná). After incubation at 37°C for 7 days, it was found, a sample that had protein precipitation, regarding microbiological standards, 19.7% did not comply with the legislation (10² CFU ml⁻¹). The values of defatted dry extract and acidity were presented the highest occurrence of irregularities. AFM₁ was found in 13.2%and AFB₁ was found in seven samples. The principal component analysis (PCA) confirmed that defatted dry extract (PC 1) and fat (PC 2) were related to the contamination by aflatoxin.

中文翻译：

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牛奶质量的季节性变化：物理化学，微生物学和毒理学

这项研究的目的是评估在通过超高温系统处理的全脂，半脱脂和脱脂奶的三个样本中，除了黄曲霉毒素M ₁和B _{1的存在外}，还有三种样品中的黄曲霉毒素M ₁和B _1的存在。巴西南部各州（南里奥格兰德州，圣卡塔琳娜州和巴拉那州）。在37°C下孵育7天后，发现有一个蛋白质沉淀的样品，按照微生物标准，有19.7％的含量不符合法律规定（10 ² CFU ml ^-1）。脱脂干提取物和酸度的值显示出最大的不规则性。AFM ₁在13.2％和AFB发现₁在七个样本中被发现。主成分分析（PCA）证实，脱脂的干提取物（PC 1）和脂肪（PC 2）与黄曲霉毒素的污染有关。