3.2.4 Risk assessment

Fresh-cut vegetables and fresh cut fruit

• Listeria monocytogenes

The FDA/USDA (2003) quantitative risk assessment on L. monocytogenes assigned low relative risk rankings to fruits, vegetables, and deli-type salads. While it appears that the probability of infection is low even for persons vulnerable to listeriosis, the consequences of the illness remain severe. The high risk rating is also applied to modified atmosphere products that are stored for extended periods. The potential for growth in storage increases the ranking for MAP vegetables and salads.

• Pathogenic Escherichia coli

There have been a number of E. coli outbreaks attributed to this group of products around the world. The illness consequences are potentially severe with high rates of hospitalization and long-term effects, such as HUS and kidney problems. Food Science Australia rated the risk as high, while Gilbert et al. (2006) placed pathogenic E. coli in the highest severity category but lowest incidence category for New Zealand foods. It was concluded that it is essential that efforts continue to prevent the likelihood of foodborne transmission from this group of organisms.

• Salmonella serovars

The risk of Salmonella in these high-riskproducts is based on the severity of the illness and no consumer cooking step to eliminate the hazard. Significant risk of Salmonella serovars in fruit and vegetables is based on similar criteria to those defined by FSA, but it should be borne in mind that the increase in their production is not a condition for possible disease. This appears consistent with the many outbreaks attributed to products in which Salmonella might survive but not grow.

• Clostridium botulinum

FSArated the risk of C. botulinum in these products as high. The contributing factors are the severity of the illness, the fact that processing and packaging using MAP may increase the risk and the existence of an epidemiological link. There is no domestic epidemiological evidence to support the high risk ranking but, to date, longer shelf life vegetable products have had limited availability.

• Vegetables in oil

There appears to be clear potential for products prepared without appropriate control measures to result in a poorly acidified product, with potential to cause severe illness from pathogens such as C. botulinum. These products are sometimes prepared by small and medium enterprises, which is considered to increase the risk if knowledge of food safety controls is not adequate.

• Seed sprouts

The conditions during sprouting (time, temperature, water activity, pH, and nutrients) are ideal for growth of pathogenic bacteria such as Salmonella and pathogenic E. coli, leading to seed sprouts being considered a high risk product. The potential for growth of pathogenic organisms during sprouting increases the risk substantially, and there is epidemiological evidence to demonstrate that contamination does occur. The implementation of control measures, such as sanitation of seeds prior to sprouting, may lower the prevalence of pathogens.

• Unpasteurized fruit juice

The high risk ranking of unpasteurized juice is appropriate. The potential sources of contamination are virtually identical as those in fresh cut fruit, and there is strong epidemiological evidence to justify the risk. The two large-scale outbreaks in Australia, in 1991 and 1999, due to contamination of unpasteurized juice with Salmonella serovars have clearly demonstrated the potential for unpasteurized juice to cause illness.