The findings from researchers at the University of Limerick in Ireland come as food manufacturers globally attempt to reduce salt levels in their products in response to the health concerns linked to the substance. However, because salt also has properties as a preservative, an industry move to slash sodium levels could be expected to increase the risk of food spoilage by bacteria. But the latest findings, presented today at the Society for General Microbiology's 161st Meeting at the University of Edinburgh, UK, confirm that low salt foods are just as safe as - or even safer than - high salt products. "In general we discovered that the growth of different sorts of typical food spoilage bacteria was unaffected by the various salt levels we tested, which means that low salt foods are just as safe as conventionally processed ones" said Edel Durack, who presented the results. The scientists checked safety levels of low salt foods by studying the behaviour of different strains of food spoilage bacteria inoculated into model systems. All the bacteria studied were capable of growing in the highest concentration - 3 percent - of salt used, they said. Even at this level of salt none of the bacteria experienced any difficulty in surviving for 24 hours. The researchers did find differences between the salt tolerances of all the bacteria tested, and contrary to what might be expected, their results confirmed that some bacteria strains actually exhibited greater resistance to the high salt environment. This is in line with previous findings that have shown salt to have a stimulating effect on some types of bacteria. This confirms that rather than keeping food products safer, high levels of salt in some foods may actually place these at a greater risk of bacterial spoilage than they need to be. "At the moment our results are helping processors reduce salt levels in frozen ready-to-eat meals. Generally these meals carry a large percentage of the recommended daily allowance of salt. This type of food is becoming increasingly popular and is in high demand due to its convenience and time restrictions placed on consumers due to modern day lifestyles," said Durack. Salt is of course a vital nutrient and is necessary for the body to function, but salt reduction campaigners such as the Consensus Action on Salt and Health (CASH) consider the average daily salt consumption in the western world, between 10 and 12g, far too high. Numerous scientists are convinced that high salt intake is responsible for increasing blood pressure (hypertension), a major risk factor for cardiovascular disease. "Hopefully our study will lead to the development of a new range of low salt foods that will help people to reduce salt levels in their diet, reducing their risk of cardiovascular diseases linked to excess sodium, without compromising product safety," said Durack. In the UK, Ireland and the USA, over 80 per cent of salt intake comes from processed food, with 20 per cent of salt intake coming from meat and meat products, and about 35 per cent from cereal and cereal products. Yet salt reduction remains a major challenge, not only in terms of taste but also formulation, as salt is a vitally important compound in food manufacturing. In processed meat products, for example, salt is involved in activating proteins to increase water-binding activity, improves the binding and textural properties of proteins, and helps with the formation of stable batters with fat.