Effect of the food production chain from farm practices to vegetable processing on outbreak incidence

Abstract

The popularity in the consumption of fresh and fresh-cut vegetables continues to increase globally. Fresh vegetables are an integral part of a healthy diet, providing vitamins, minerals, antioxidants and other health-promoting compounds. The diversity of fresh vegetables and packaging formats (spring mix in clamshell container, bagged heads of lettuce) support increased consumption. Unfortunately, vegetable production and processing practices are not sufficient to ensure complete microbial safety. This review highlights a few specific areas that require greater attention and research. Selected outbreaks are presented to emphasize the need for science-based ‘best practices’. Laboratory and field studies have focused on inactivation of pathogens associated with manure in liquid, slurry or solid forms. As production practices change, other forms and types of soil amendments are being used more prevalently. Information regarding the microbial safety of fish emulsion and pellet form of manure is limited. The topic of global climate change is controversial, but the potential effect on agriculture cannot be ignored. Changes in temperature, precipitation, humidity and wind can impact crops and the microorganisms that are associated with production environments. Climate change could potentially enhance the ability of pathogens to survive and persist in soil, water and crops, increasing human health risks. Limited research has focused on the prevalence and behaviour of viruses in pre and post-harvest environments and on vegetable commodities. Globally, viruses are a major cause of foodborne illnesses, but are seldom tested for in soil, soil amendments, manure and crops. Greater attention must also be given to the improvement in the microbial quality of seeds used in sprout production. Human pathogens associated with seeds can result in contamination of sprouts intended for human consumption, even when all appropriate ‘best practices’ are used by sprout growers.

Geraniol-Loaded Polymeric Nanoparticles Inhibit Enteric Pathogens on Spinach during Posttreatment Refrigerated and Temperature Abuse Storage

“…Immediately following treatment by FAC, unencapsulated or nanoparticle-entrapped geraniol, Escherichia coli O157:H7 and Salmonella counts on spinach ranged from 1.5 to 6.1 log10 CFU/cm 2 . Geraniol-loaded nanoparticles reduced pathogens to non-detectable numbers (detection limit: 0.5 log10 CFU/cm 2 ) on refrigerated and moderately temperature-abused samples (15°C) within 7 days of storage posttreatment, and Microbial pathogens have been associated with a variety of produce-borne human disease outbreaks, with an apparent increase in the frequency of outbreaks in recent years (CDC, 2012a,b;Gould et al, 2013;Slayton et al, 2013;Jung et al, 2014;Angelo et al, 2015). Painter et al (2013) reported leafy green produce commodities were the most frequently implicated pathogen transmission vehicles in US human foodborne disease cases, as well as the food vehicle type second most frequently linked to hospitalizations resulting from foodborne disease.…”

Occurrence of Escherichia coli in Brassica rapa L. chinensis irrigated with low quality water in urban areas of Morogoro, Tanzania

“…Although there is no established criteria for concentration of E. coli in the raw leafy vegetables (ICMSF, 1986), concentration of E. coli >3 log cfu/g observed in this study may pose health risks to consumers. This was expected, because Jung et al, 2014). However, Chinese cabbage which has a natural epiphytic flora, it may acquire contamination from various incidental and accidental inputs.…”

“…The potential sources of pathogen contamination during preharvest practices may include dust, soil, polluted irrigation water and rodents (Jung et al, 2014). Previous studies conducted on leafy vegetables in Ghana (Keraita et al, 2007) and in Pakistan (Ensink et al, 2007) during pre-and post-harvest handling practices reported faecal pathogens contamination.…”

“…Although Chinese cabbage is heated prior to consumption, inadequate preparation could expose consumers to potential health risks. Although in developing countries, untreated wastewater is often used for irrigation of crops (Jung et al, 2014), data on occurrence of pathogenic bacteria on green leafy vegetables including Chinese cabbage are limited (Erickson, 2010). The aim of this study was, therefore, to determine the extent of contamination of E. coli in Chinese cabbage and low quality irrigation water.…”

Distribution of Pathotypes of E.coli in seafood from retail markets of Kerala (India)

“…Use of sewage contaminated water in the food production chain can lead to emergence of water borne diseases particularly by pathogens of public health importance (Jung et al, 2014).…”