Optimization of decontamination conditions for Aspergillus flavus inoculated to military rations snack and physicochemical properties with atmospheric cold plasma

Abstract

AbstractIn this study, the effectiveness of ACP in inactivating Aspergillus flavus inoculated to military rations snack using response surface methodology (RSM) was investigated. Additionally, the effect of this treatment on the total count and yeast–mold count, as well as some quality properties of military rations snack, was examined. RSM was applied to study the voltage effects (5–15 kV), the distance between ACP emitter and sample (3–7 cm), and different treatment time (2–10 min) on the physicochemical properties of the military rations snack. Increasing voltage and time, together with reducing distance, caused a decrease in A. flavus, total count, yeast and mold count, total aflatoxin, as well as color difference. The peroxide value also increased with increasing voltage levels. The optimum conditions for treated military rations snack by ACP are as follows: a system voltage of 9 kV, a distance of 3 cm between the sample and the emitter, and a time of 6 min. Under these conditions, the responses, including the utmost reduction of 4.31 log CFU/g for the total count, 4.64 log CFU/g for yeast–mold count, and 2.98 log CFU/g for A. flavus were found from starting level of 5.2, 2, and 3.1 log CFU/g, respectively. It was found that snack samples had a 3.66% decrease in moisture content, 76.13% decrease in total aflatoxin, 3.01% increase in color difference, and 0.22 meq O2.kg/oil increase in peroxide value as a result of ACP application. ACP has the potential to increase microbiological safety by maintaining desirable quality properties in military rations snack.