Biochemical tests for the selection ofStaphylococcusstrains as potential meat starter cultures

A fast screening procedure has been applied for the isolation of staphylococcal strains with possible value as starter cultures in fermented meat products. Colonies isolated in MSA (mannitol-salt phenol red-agar) from a naturally fermented spanish ‘salchichón’ were stabbed into KNO3-containing agar plates. Then, colonies showing very high and low nitrate reductase activity were selected and used in further biochemical tests. All strains were identified asStaphylococcus xylosus, with the exception of oneStaphylococcus epidermidisisolate. In addition to the APIZYMRgalleries, other activities were quantified, such as, nitrate reductase, catalase, proteases and lipases. High nitrate reductase was found in some of the strains. Lipase activity was found in different strains, and all of them had an interesting cell-bound proteinase activity when assayed against β-casein. Another study should be undertaken to test these strains ofS. xylosusfor the production of fer?mented meat products, and their activities correlated to the development of desirable physicochemical and organoleptic characteristics.