A COMPARISON OF Microbacterium thermosphactum AND LACTOBACILLI AS SPOILAGE ORGANISMS OF VACUUM‐PACKAGED SLICED LUNCHEON MEATS

TLDR

In vacuum‑packaged sliced luncheon meats, a simple total bacterial count is insufficient to predict spoilage risk. The study evaluated spoilage of vacuum‑packaged sliced luncheon meats at 5 °C by Microbacterium thermosphactum and lactobacilli using analytical taste panels. Microbacterium thermosphactum rapidly induced off‑aroma at ~10⁸ CFU g⁻¹ and off‑flavor 2–3 days later, whereas homofermentative lactobacilli caused much slower spoilage with no off‑aroma at similar counts, heterofermentative strains were intermediate, showing that shelf life depends on bacterial species.

Abstract

ABSTRACT The spoilage of vacuum‐packaged sliced luncheon meats at 5°C by Microbacterium thermosphactum and lactobacilli was studied using analytical taste panels. M. thermosphactum caused rapid spoilage. “Off” aroma was significant at about the time the bacterial population reached 10 8 /g and “off” flavor 2–3 days later. In contrast homofermentative lactobacilli caused spoilage much more slowly. No “off” aroma was detected with products which had carried a population of 10 8 /e. for 21 days the time at which “off” flavor first became significant. Heterofermentative lactobacilli were intermediate in their effect. Thus shelf life is dependent upon the types of bacteria present. Under such circumstances a “total count” microbiological standard is of little value.