Mould-ripened meat products: New selection scheme for non-toxigenicPenicillium spp.

Species belonging to the genusPenicillium are known to produce a variety of mycotoxins. The use of non-toxigenic isolates is therefore of a major concern when selecting strains for improving mould-ripened food products. For initial selection 249 different strains of the genusPenicillium originally isolated from food products have been used in this study. The isolates were grouped according to the pattern of their secondary metabolites by TLC methods. Mould ripened salamis were then produced to prove the technological suitability of the strains. The potency of selected strains to produce antibiotic, cytotoxic and mutagenic metabolites was proven by the use of bacterial test systems, the MTT (3-(4.5-dimethylthiazol-2yl)-2.5-diphenyltetrazoliumbromide) -cell culture bioassay and the AMES-test, respectively. A total of 13 isolates out of 249 strains tested were found to meet the demands on technological suitability and toxicological safety to the greatest extent and could thus be recommended for the use in the meat industry. The chemotaxonomic characterisation of the strains showed correlation with the technological suitability and offers a simple but useful first step in selecting appropriate strains. Moreover, the overall selection scheme presented in this study was found to be useful for screening out toxigenic species and to enhance food safety aspects.