通过商业规模的高压加工在水果汁中使食源性病原体无活化:酸剂和pH的影响
Rebecca M Cheng1, Jessie Usaga1,2, Randy W Worobo1
1Department of Food Science, Cornell University, Geneva, New York, USA.
概括
高压加工 (HPP) 有效地使诸如大肠杆菌,沙门氏菌和菌在果汁中的病原体无活化. 在HPP后的冷却增强了病原体的减少,特别是在较低的pH值.
科学领域:
- 食品微生物学 食品微生物学
- 食品加工技术 食品加工技术
- 食品安全 食品安全
背景情况:
- 酸性饮料容易受到微生物污染,造成食品安全风险.
- 高压加工 (HPP) 是一种非热技术,用于食品中的微生物无活化.
- 了解影响HPP疗效的因素对于确保酸性饮料的安全至关重要.
研究的目的:
- 评估果汁的pH值,酸剂类型和处理后冷却对HPP关键食物传播病原体的失活的影响.
- 在各种果汁和模型溶液中,确定HPP对*Escherichia coli* O157:H7,*Salmonella enterica*和*Listeria monocytogenes*的有效性.
主要方法:
- 接种过的果,子和葡萄汁在各种pH值下经过HPP (550MPa,1分钟,5°C) 处理.
- 用不同的有机酸酸化的模型溶液使用HPP (400MPa,1分钟,5°C) 进行处理.
- 评估了HPP后24小时冷藏存储对病原体减少的影响.
主要成果:
- 在所有条件下,HPP在原始pH值和*L. monocytogenes*的汁液中实现了所有三种病原体的>5-log降低.
- 在HPP后的制冷过程中,在果汁中的pH值为4.00时,增强了*E. coli* O157:H7和*Salmonella*的无活化.
- 酸剂类型对大肠杆菌和沙门氏菌的失活影响最小,但酸对L. monocytogenes最有效.
结论:
- HPP是一种可行的方法来减少酸性饮料中的病原体,其有效性取决于产品的pH值和特定的病原体.
- 处理后的制冷可以显著提高HPP处理的酸性饮料的微生物安全性.
- 优化HPP参数和考虑后处理条件对于果汁中有效的病原体控制至关重要.
相关概念视频
00:53Extraction: Effects of pH
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03:27Mixtures of Acids
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02:11Leveling Effect and Non-Aqueous Acid-Base Solutions
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03:22Strong Acid and Base Solutions
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02:41pH Scale
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