New microbes, more virulent strains, superbugs resistant to a multiplicity of antibiotics, and centralised distribution of food have all upped the ante in combatting food poisoning. Within 24 hours, produce can not only be shifted across the globe but, in the case of Ireland for example, can be in a distribution centre near Dublin at lunch-time and in south-west Cork by nightfall.
So when a major food poisoning outbreak occurs, tracing the source is as important as it is difficult. How the risk is reduced differs on both sides of the Atlantic. The US is leading the way in terms of intervention before outbreaks occur. Europeans are often less keen to deploy aggressive food safety measures.
DNA fingerprinting/rapid assay techniques are now being used routinely in the US and increasingly in Ireland to detect impurities or pathogenic bacteria in or on food products. This involves comparing genetic material (DNA) in the bacteria.
Irradiation has been shown to be such an effective eliminator of harmful bacteria that its use is being allowed extensively in the US. Europe is not likely to follow due to consumer resistance, though some products imported into the EU, notably some spices, are irradiated. The process exposes food to radiant energy which delays spoilage or eliminates harmful bacteria.
Competitive bacteria compete with and often eliminate pathogens such as E coli 0157 or salmonella. These are being used in some poultry production systems in the US. The use of competitive or probiotic species has great potential, even if the scientific basis for their success has yet to be fully understood.
Ozone is increasingly being used in water treatment and sanitation. Some scientists now believe it has more applications in food processing than chlorine.
Chlorine baths and trisodium phosphate sprays or dips are used in poultry processing in the US, while the US Food and Drug Administration has approved chlorine dioxide as an anti-microbial agent in water to wash certain fruits and vegetables.