Ukuku Dike O, Bari M L, Kawamoto S, Isshiki K
Food Safety Intervention Technologies Research Unit, Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA.
Int J Food Microbiol. 2005 Oct 15;104(2):225-33. doi: 10.1016/j.ijfoodmicro.2005.01.016.
Hydrogen peroxide (2.5%) alone or hydrogen peroxide (1%) in combination with nisin (25 microg/ml), sodium lactate (1%), and citric acid (0.5%) (HPLNC) were investigated as potential sanitizers for reducing Escherichia coli O157:H7 or Listeria monocytogenes populations on whole cantaloupe and honeydew melons. Whole cantaloupes inoculated with E. coli O157:H7 and L. monocytogenes at 5.27 and 4.07 log10 CFU/cm2, respectively, and whole honeydew melons inoculated with E. coli O157:H7 and L. monocytogenes at 3.45 and 3.05 log10 CFU/cm2, respectively, were stored at 5 degrees C for 7 days. Antimicrobial washing treatments were applied to inoculated whole melons on days 0 or 7 of storage and surviving bacterial populations and the numbers transferred to fresh-cut pieces were determined. At days 0 and 7 treatment with HPLNC significantly (p<0.05) reduced the numbers of both pathogens, by 3 to 4 log CFU/cm2 on both types of whole melon. Treatment with HPLNC was significantly (p<0.05) more effective than treatment with 2.5% hydrogen peroxide. While fresh-cut pieces prepared from stored whole melons were negative for the pathogens by both direct plating and by enrichment, fresh-cut pieces from cantaloupe melons treated with 2.5% hydrogen peroxide were positive for both pathogens and pieces from honeydew melons were positive for E. coli 0157:H7. The native microflora on fresh-cut melons were also substantially reduced by HPLNC treatment of whole melons. The results suggest that HPLNC could be used to decontaminate whole melon surfaces and so improve the microbial safety and quality of fresh-cut melons.
研究了单独使用过氧化氢（2.5%）或过氧化氢（1%）与乳酸链球菌素（25微克/毫升）、乳酸钠（1%）和柠檬酸（0.5%）组合（HPLNC）作为潜在消毒剂，以减少完整哈密瓜和白兰瓜上的大肠杆菌O157:H7或单核细胞增生李斯特氏菌数量。分别以5.27和4.07 log10 CFU/cm²接种大肠杆菌O157:H7和单核细胞增生李斯特氏菌的完整哈密瓜，以及分别以3.45和3.05 log10 CFU/cm²接种大肠杆菌O157:H7和单核细胞增生李斯特氏菌的完整白兰瓜，在5℃下储存7天。在储存的第0天或第7天对接种的完整甜瓜进行抗菌清洗处理，并测定存活的细菌数量以及转移到鲜切片中的数量。在第0天和第7天，用HPLNC处理显著（p<0.05）减少了两种病原体的数量，在两种类型的完整甜瓜上均减少了3至4 log CFU/cm²。用HPLNC处理显著（p<0.05）比用2.5%过氧化氢处理更有效。虽然从储存的完整甜瓜制备的鲜切片通过直接平板计数和富集培养对病原体均呈阴性，但用2.5%过氧化氢处理的哈密瓜鲜切片对两种病原体均呈阳性，白兰瓜鲜切片对大肠杆菌O157:H7呈阳性。通过对完整甜瓜进行HPLNC处理，鲜切甜瓜上的天然微生物群落也大幅减少。结果表明，HPLNC可用于对完整甜瓜表面进行去污，从而提高鲜切甜瓜的微生物安全性和质量。
