Ghent University, Faculty of Bioscience Engineering, Department of Food Safety and Food Quality, Laboratory of Food Microbiology and Food Preservation (LFMFP), Ghent, Belgium.
Food Microbiology Laboratory of Food Science and Technology Institute (ICTA) of Federal University of Rio Grande do Sul (ICTA/UFRGS), Porto Alegre, Brazil.
Int J Food Microbiol. 2014 Jul 2;181:67-76. doi: 10.1016/j.ijfoodmicro.2014.04.025. Epub 2014 May 1.
The microbiological quality and safety of lettuce during primary production in Brazil were determined by enumeration of hygiene indicators Escherichia coli, coliforms and enterococci and detection of enteric pathogens Salmonella and E. coli O157:H7 in organic fertilizers, soil, irrigation water, lettuce crops, harvest boxes and worker's hands taken from six different lettuce farms throughout the crop growth cycle. Generic E. coli was a suitable indicator for the presence of Salmonella and E. coli O157:H7, while coliforms and enterococci were not. Few pathogens were detected: 5 salmonellae and 2 E. coli O157:H7 from 260 samples, of which only one was lettuce and the others were manure, soil and water. Most (5/7) pathogens were isolated from the same farm and all were from organic production. Statistical analysis revealed the following environmental and agro-technical risk factors for increased microbial load and pathogen prevalence in lettuce production: high temperature, flooding of lettuce fields, application of contaminated organic fertilizer, irrigation with water of inferior quality and large distances between the field and toilets. Control of the composting process of organic fertilizers and the irrigation water quality appear most crucial to improve and/or maintain the microbiological quality and safety during the primary production of lettuce.
本研究旨在调查巴西生菜初级生产过程中的微生物质量和安全情况，通过对有机肥料、土壤、灌溉用水、生菜作物、收获箱和工人手部的卫生指标（大肠杆菌、大肠菌群和肠球菌）进行计数，并检测肠道病原体沙门氏菌和大肠杆菌 O157:H7，对 6 个不同的生菜农场进行了研究。在整个作物生长周期中。普通大肠杆菌是沙门氏菌和大肠杆菌 O157:H7存在的合适指标，而大肠菌群和肠球菌则不是。从 260 个样本中仅检测到 5 株沙门氏菌和 2 株大肠杆菌 O157:H7，其中只有一株来自生菜，其余均来自粪肥、土壤和水。大多数（5/7）病原体来自同一农场，均来自有机生产。统计分析表明，以下环境和农业技术风险因素会增加生菜生产中的微生物负荷和病原体流行率：高温、生菜田洪水泛滥、使用受污染的有机肥料、水质较差的灌溉以及田地和厕所之间的距离较大。控制有机肥料的堆肥过程和灌溉水质量似乎对改善和/或维持生菜初级生产过程中的微生物质量和安全至关重要。
