Application of vacuum-steam-vacuum (VSV) technology for corn decontamination

Corn is a nutritious food which is stored in ensilage. Bacterial contamination is the most important problem in storage condition. Vacuum-Steam-Vacuum (VSV) Technology is a safe technique for microbial decontamination of food. In this methods decontaminating done by steam which effects thermally and mechanically to microbial destruction.
Statistical Analysis was carried out based on full factorial designs that repeated three times in the form of random plan. Independent variables in this research were temperature (115, 120, 125 °C), steaming time (15, 20, 25 seconds) and first vacuum's time (60, 90 and 120). Dependent variables were Total bacterial load, Total moulds and yeast, moisture content, ash, sensory attributes (color, smell and overall acceptability).
The results showed that the best bacterial decontamination was carried out in the following condition: treatment temperature 125 °C, the first vacuum time 90 s, steaming time 25 s and the second vacuum time 120 s. In this condition a decontamination rate of 4 log CFU for total bacterial count and 3.6 reduction log CFU in total mold and yeast was resulted. The highest percentage of moisture content in treated samples was 9.2 % which lower than national standards (13%). This technology as an applicable technique for food decontamination was advice.