FACTORS AFFECTING THE EFFICACY OF WASHING PROCEDURES USED IN THE PRODUCTION OF PREPARED SALADS
FACTORS AFFECTING THE EFFICACY OF WASHING PROCEDURES USED IN THE PRODUCTION OF PREPARED SALADS
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DOI：
10.1016/s0740-0020(89)80039-5
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发表时间：
1989-01-01
期刊：
影响因子：
--
通讯作者：
COX L J
中科院分区：
文献类型：
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作者：
ADAMS M R;HARTLEY A D;COX L J
整个生菜的外部叶子的数量比随后的内部叶子层的数量高出大约 1 个对数周期。在自来水中进行标准清洗后，平均 92.4% 的生菜叶微生物群被去除。添加 100 mg l-1 (pH c.9) 有效游离氯可使计数减少 97.8%。用无机酸或有机酸将次氯酸盐溶液的 pH 值从 c.9 调节至 4.5-5.0，杀菌效果可提高 1.5-4.0 倍。将次氯酸盐清洗时间从 5 分钟增加到 30 分钟并没有进一步减少微生物数量，而延长自来水清洗的减少量与次氯酸盐相当。在次氯酸盐中添加表面活性剂 Tween 80 可将微生物数量减少 99.6%，但会导致感官差异。传统的水和次氯酸盐洗涤未能去除更多的微生物区系，这归因于细菌在叶子表面的保护性疏水袋或褶皱中的存活，并且提出了一些支持性的电子显微镜证据。
External leaves of whole lettuce were found to have counts approximately 1 log cycle higher than subsequent inner leaf layers. A standard washing in tap water resulted in the removal of an average of 92.4% of the lettuce leaf microflora. Inclusion of 100 mg l-1 (pH c.9) available free chlorine reduced the count by 97.8%. Adjusting the pH of hypochlorite solutions from c.9 to 4.5-5.0 with inorganic or organic acids produced a 1.5-4.0 fold increase in the microbiocidal effect. Increasing the washing time in hypochlorite from 5 to 30 min did not decrease microbial numbers further whereas extended washing in tap water produced a reduction comparable to hypochlorite. Addition of a surfactant, Tween 80, to hypochlorite reduced microbial numbers by 99.6% but resulted in organoleptic differences. Failure of conventional water and hypochlorite washing to remove more of the microflora is ascribed to the survival of bacteria in protective hydrophobic pockets or folds in the leaf surface and some supportive electron microscopy evidence is presented.