Aerococci and carnobacteria cause discoloration in cooked cured bologna Original Research Article

Three groups of alkalitrophic lactic acid bacteria were isolated from discolored bologna and from a bologna manufacturing plant. The organisms grew on vacuum-packaged bologna at both 4°C and 9°C and induced green discoloration in ⩽3 d upon exposure to air. Weissella viridescens ATCC 12706 also caused greening but Enterococcus faecalis ATCC 7080 and a variety of other strains did not. The organisms that caused greening in meat were Aerococcus viridans and Carnobacterium viridans. Meat–agar test systems failed to predict an organismʹs ability to produce green discoloration. The speed and extent of green discoloration varied greatly depending on the organism and the composition of the bologna. We suggest that greening in cooked cured meats may often be due to alkalitrophic bacteria and not to the acidiphilic lactobacilli, leuconostocs or pediococci, as is commonly thought.