Department of Comparative Biomedicine and Food Science, University of Padova, Viale Università 16, 35020 Legnaro, PD, Italy; Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29280 Plouzané, France.
Department of Comparative Biomedicine and Food Science, University of Padova, Viale Università 16, 35020 Legnaro, PD, Italy.
Int J Food Microbiol. 2024 Feb 2;411:110523. doi: 10.1016/j.ijfoodmicro.2023.110523. Epub 2023 Dec 18.
Traditional products are particularly appreciated by consumers and among these products, cheese is a major contributor to the Italian mountainous area economics. In this study, shotgun metagenomics and volatilomics were used to understand the biotic and abiotic factors contributing to mountain Caciotta cheese typicity and diversity. Results showed that the origin of cheese played a significant role; however, curd cooking temperature, pH, salt concentration and water activity also had an impact. Viral communities exhibited higher biodiversity and discriminated cheese origins in terms of production farms. Among the most dominant bacteria, Streptococcus thermophilus showed higher intraspecific diversity and closer relationship to production farm when compared to Lactobacillus delbrueckii. However, despite a few cases in which the starter culture was phylogenetically separated from the most dominant strains sequenced in the cheese, starter cultures and dominant cheese strains clustered together suggesting substantial starter colonization in mountain Caciotta cheese. The Caciotta cheese volatilome contained prominent levels of alcohols and ketones, accompanied by lower proportions of terpenes. Volatile profile not only demonstrated a noticeable association with production farm but also significant differences in the relative abundances of enzymes connected to flavor development. Moreover, correlations of different non-homologous isofunctional enzymes highlighted specific contributions to the typical flavor of mountain Caciotta cheese. Overall, this study provides a deeper understanding of the factors shaping typical mountain Caciotta cheese, and the potential of metagenomics for characterizing and potentially authenticating food products.
传统产品尤其受到消费者的赞赏，而在这些产品中，奶酪是意大利山区经济的主要贡献者。在这项研究中，我们使用组合式宏基因组学和挥发组学来了解促成山地卡伊奥塔奶酪典型性和多样性的生物和非生物因素。结果表明，奶酪的起源起着重要作用；然而，凝乳烹饪温度、pH 值、盐浓度和水活度也有影响。病毒群落表现出更高的生物多样性，并根据生产农场来区分奶酪的起源。在最主要的细菌中，嗜热链球菌表现出更高的种内多样性，并且与生产农场的关系比德氏乳杆菌更密切。然而，尽管在少数情况下，起始培养物在系统发育上与奶酪中测序的最主要菌株分离，但起始培养物和主要奶酪菌株聚集在一起，表明在山地卡伊奥塔奶酪中存在大量的起始培养物定植。卡伊奥塔奶酪的挥发组含有大量的醇类和酮类，萜烯类的比例较低。挥发性图谱不仅与生产农场有明显的关联，而且与与风味发展相关的酶的相对丰度也有显著差异。此外，不同非同源同工酶的相关性突出了对山地卡伊奥塔奶酪典型风味的特定贡献。总的来说，本研究深入了解了塑造典型山地卡伊奥塔奶酪的因素，以及宏基因组学在表征和潜在认证食品产品方面的潜力。
