Leuconostoc spoilage of vacuum-packaged vegetable sausages.

The present study was conducted to assess the role of lactic acid bacteria (LAB) in spoilage of a vacuum-packaged vegetable sausage product. This spoilage problem was characterized by formation of gas and slime, and was limiting the shelf life of the product. To investigate the LAB populations, LAB were enumerated in vegetable sausages graded as either spoiled or acceptable. From these vegetable sausages, 110 prevailing LAB isolates were recovered and identified using an LAB ribotyping database, which uses HindIII restriction fragment length polymorphism patterns of the 16S and 23S rRNA genes as operational taxonomic units. Finally, to determine the effects of the prevailing LAB on the sensory properties of the product, fresh vegetable sausages were inoculated with six LAB strains. The results revealed that Leuconostoc gelidum, Leuconostoc gasicomitatum, and Leuconostoc mesenteroides were the predominant LAB in the commercial vegetable sausages. The inoculation of these LAB onto vegetable sausages resulted in the formation of gas, slime, and a sour off-odor. Based on these findings, L. gelidum, L gasicomitatum, and L. mesenteroides were responsible for spoilage of the vegetable sausage product.