Sensitivity of Spores to Hydrostatic Pressure Mechanisms of Inactivation, Injury and Repair Phase II.

摘要

Over the past fifteen years, it has been established that high- hydrostatic pressure processing (HPP) has significant potential to function as an effective nonthermal method in the destruction of microorganisms in foods with little effect on the sensory qualities of the food product. However, bacterial endospores are very pressure-resistant and have been shown to require a hurdle approach for inactivation when HPP is employed. This study investigated the inhibitory effect of approved emulsifiers (sucrose esters) in comparison to the widely studied mono-glyceride, monolaurin (Lauricidin) on Bacillus sp., Clostridium sporogenes, and Alicyclobacillus sp. The combined treatments of sucrose laurate, HPP and mild heat were evaluated on spores of Bacillus and Alicyclobacillus in foods. The minimum inhibitory concentrations (MICs) of the sucrose esters were higher for Bacillus, Clostridium, and Alicyclobacillus spp. than of Lauricidin. Sucrose stearates and sucrose palmitate were less effective and less soluble than sucrose laurates. A combined treatment (sucrose laurate L1695 CONCNS 0.1 AND 0.5%, 392 megaPascals MPa at 45 C for 10 to 15 min) provided 4.5-to 5.5-log(sub 10) CFU/mL reductions from initial populations of 106 CFU/mL for Bacillus subtilis 168 in milk, Bacillus cereus 14579 in beef, Bacillus coagulans 7050 in tomato juice (pH 4.5), Alicyclobacillus sp. N1089 in tomato juice (pH 4.5) and Ali clobacillus s . N1098 in apple juice.