Feasibility of Using Sucrose Laurate to Control Thermophilic Spoilage in Low-Acid Canned Rations.

The individual and combined effects of sucrose laurate SL, L-1695, tert-butylated hydroxyanisole B ethylenediamine tetraacetate E and nisin were evaluated in a liquid growth medium antibiotic assay medium 1 soluble starch, AAMS to determine their antagonistic action against the thermophilic flat-sour bacterium, B. stearothermophilus. Results indicated that on AAMS agar pH 6.5 - 6.8 the minimum inhibitory concentration MIC of these additives required to prevent germination and outgrowth of B. stearothermophilus spores were 50-60 ppm for SL and SLEB, while the MICs for BHA, EDTA and nisin were 150, 350 and 400 ppm, respectively. During incubation 144 h at 55 deg C in AAMS broth pH 6.8 containing 50 ppm of SL and SLEB, respectively, the vegetative cell number increased ca. 2 log10 cycles, e.g., 103 -.105 CFUmL. At similar concentrations of BHA, EDTA and nisin, no inhibition was observed. SL and SLEB did, however, prolong the lag phase and arrest log phase growth BHA, EDTA and nisin did not exhibit similar inhibition tendencies. Differences in the inhibitory properties of SL and SLEB, relative to B. stearothermophilus, were not statistically significant p0.05. Under the conditions defined in this study, it would appear that SL and SLEB may have some utility in protecting thermally processed military rations from thermophilic spoilage.