EFSA has assessed the risks to public health from Listeria contamination of vegetables that are blanched – scalded in hot water or steam for a short time – before they are frozen. They conclude that the risks associated with the consumption of these products is lower than for ready-to-eat foods such as smoked fish, cooked meat, sausages, pâté, soft cheese – which are usually associated with listeria contamination.
Food business operators often blanch vegetables before freezing them because this stops enzyme actions which can cause loss of flavour, colour and texture.
EFSA’s experts identified relevant control activities that food business operators can implement to lower the risks of contamination of frozen vegetables. These range from cleaning and disinfection of the food producing environment to water, time and temperature control at different processing steps, and accurate labelling.