Industrial application of an antilisterial strain of Lactobacillus sakei as a protective culture and its effect on the sensory acceptability of cooked, sliced, vacuum-packaged meats

Abstract

The application of a protective lactic acid bacterium (LAB) during the commercial production of cooked meat products is described. The LAB, a strain of Lactobacillus sakei, was previously isolated from cooked ham and inhibited growth of Listeria monocytogenes and Escherichia coli O157:H7 in this product. L. sakei was applied to the cooked products at a concentration of 10⁵–10⁶ cfu/g immediately before slicing and vacuum-packaging using a hand-operated spraying bottle. The LAB strain inhibited growth of 10³ cfu/g of a cocktail of three rifampicin resistant mutant L. monocytogenes strains both at 8°C and 4°C. Consumer acceptance tests of cooked ham and of servelat sausage, a Norwegian non-fermented cooked meat sausage, showed that control and inoculated products were equally acceptable. The products were still acceptable after storage for 28 days at 4°C and, after opening the packages, for a further 5 days at 4°C. The findings presented here confirm that the L. sakei strain is suitable for use as a protective culture and may technically easily be implemented in the commercial production of cooked meat products.