Abstract Pink discoloration in cheese has been the subject of wide research, but the basis for this phenomenon remains elusive. This defect impacts a wide range of ripened cheeses, resulting in the rejection of cheese and a consequent economic loss for dairy industries. As multiple causes for pink discoloration have been reported for different cheeses in the literature, the aim of this research was to investigate the cause of a pink discoloration found on Pecorino Toscano cheese rind. The results of microbiological analysis revealed the presence of high microbial counts associated to the rind and the nearest inner part. Strains isolated from the coloured part were mainly identified as Serratia liquefaciens, suggesting that an environmental contamination of the cheese rind by this species could be the cause of the observed defect and expanding the knowledge related to pink discoloration in cheeses.

中文翻译：

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关于奶酪粉红色变色的新见解：以 Pecorino Toscano 为例

摘要 奶酪中的粉红色变色一直是广泛研究的主题，但这种现象的基础仍然难以捉摸。这种缺陷会影响范围广泛的成熟奶酪，导致奶酪被拒收，从而给乳制品行业造成经济损失。由于文献中报道了不同奶酪出现粉红色变色的多种原因，因此本研究的目的是调查 Pecorino Toscano 奶酪外皮出现粉红色变色的原因。微生物分析的结果揭示了与外皮和最近的内部部分相关的高微生物计数的存在。从有色部分分离的菌株主要被鉴定为Serratia liquefaciens，