PDF(Pubmed)
Abstract：
Vegetative cells of Listeria monocytogenes and Escherichia coli and spores of Bacillus subtilis and Aspergillus niger were inoculated in soy milk at an initial concentration of ≈5 log CFU/mL. Inoculated and control (non-inoculated) soy milk samples were submitted to three types of treatments using a tubular annular thin film short-wave ultraviolet (UV-C) reactor with 1 mm of layer thickness. Treatments applied depended on the flow rate and the number of entries to the reactor, with UV-C doses ranging from 20 to 160 J/mL. The number of entries into the reactor tube (NET) was established as the most determining parameter for the efficiency of the UV-C treatments. Conidiospores of A. niger were reported as the most resistant, followed by B. subtilis spores, while vegetative cells were the most sensible to UV-C, with Listeria monocytogenes being more sensible than Escherichia coli. Treatments of just 80 J/mL were needed to achieve a 5 log CFU/mL reduction of L. monocytogenes while 160 J/mL was necessary to achieve a similar reduction for A. niger spores.
摘要：
将单核细胞增生李斯特菌和大肠杆菌的营养细胞以及枯草芽孢杆菌和黑曲霉的孢子接种在豆浆中，初始浓度约为5logCFU/mL。使用1mm层厚的管状环形薄膜短波紫外线（UV-C）反应器，对接种和对照（未接种）的豆浆样品进行三种类型的处理。应用的处理取决于流速和进入反应器的数量，UV-C剂量范围从20到160J/mL。进入反应器管(NET)的数量被确立为UV-C处理效率的最决定性参数。据报道，黑曲霉的分生孢子抗性最强，其次是枯草芽孢杆菌孢子，营养细胞对紫外线C最敏感，单核细胞增生李斯特菌比大肠杆菌更敏感。仅需要80J/mL的处理才能实现单核细胞增生李斯特菌的5logCFU/mL减少，而黑曲霉孢子的类似减少则需要160J/mL。
