牛奶储存温度对奶酪质量和乳制品加工厂微生物群落的影响
Lucia Giagnoni1, Saptarathi Deb2, Alessandra Tondello2
1Department of Veterinary Medicine, University of Sassari, Via Vienna, 2, 07100 Sassari (SS), Italy; Department of Agronomy, Food, Natural Resources, Animals and Environment, DAFNAE, University of Padova, Viale dell'Università 16, 35020 Legnaro, (PD), Italy.
Food research international (Ottawa, Ont.)
|September 10, 2023
概括
牛奶冷藏温度通过改变细菌群体,显著影响奶酪质量. 较高的温度可以减少腐烂微生物,但需要在冷却过程中仔细控制,以防止不良细菌生长并确保最佳的奶酪成熟.
科学领域:
- 应用生物技术应用生物技术
- 食品科学 食品科学 食品科学
- 微生物学 微生物学
背景情况:
- 奶酪生产依赖于微生物动力学,从收集牛奶到成熟.
- 牛奶在巴氏杀菌前的制冷温度会影响心理变质细菌的数量.
- 标准的4°C制冷可以让耐寒的蛋白质细菌对奶酪质量产生负面影响.
研究的目的:
- 研究牛奶制冷温度变化对奶酪感官特性和细菌群落的影响.
- 分析细菌在温度梯度 (4°C至13°C及相反) 的反应中发生的变化.
- 为奶酪制造业提供有关处理热变化的见解.
主要方法:
- 一个在工厂试验使用牛奶温度梯度从4°C到13°C和反转.
- 在不同成熟阶段对奶酪进行感官分析.
- DNA提取和16S rRNA基因测序 (元编码) 用于识别牛奶和奶酪样本中的细菌群体.
主要成果:
- 确定了1714种遗传变异和394种细菌种群.
- 奶酪中显著的细菌社区转移与牛奶制冷温度相关.
- 蛋白质溶解性心理受到了13°C的抑制,但在冷却时增加到7°C,而肠杆菌和其他种类受到了更高温度的青.
结论:
- 牛奶制冷温度是影响奶酪微生物生态和感官属性的关键控制点.
- 了解细菌对温度波动的反应有助于预测和管理潜在的缺陷.
- 优化温度控制策略可以改善奶酪制造工艺和产品的一致性.
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