These are prepared with little or no heat treatment, and major spoilage can be caused by Lactobacillus and Leuconostoc spp., which produce diacetyl-butter flavors.

• 这些产品较少或没有加热处理,主要的变质是由乳杆菌属和嗜柠檬酸明串珠菌属亚种所引起的,它们产生双乙酰奶油味