Changes in Microflora of Ozone-treated Cereals, Grains, Peas, Beans and Spices during Storage

Abstract

Changes in microflora of ozone-treated cereals, grains, peas, beans and spices, packaged in a polyethylene pouch and stored at 10, 30°C for 30days were investigated. The conditions to evaluate the ozone treatment effect on various samples were: ozone concentration, 0.5-50 ppm; temperature, 10°C; time, 1h and flow rate of ozone-oxygen stream, 100l/min. Results were as follows: 1) Bacillus and Micrococcus have been found to be the main microflora of cereals, grains, peas, beans and spices. The number of the main microorganisms of these samples could be decreased by a factor of 10-10³ by the ozone treatment below 50ppm and further decreased during storage. 2) At 10 and 30°C storage, a decrease of total microbial count was mainly ascribed to ozone remained in a polyethylene pouch. Cereals and grains kept ozone for relatively long period. 3) The preservation lives of cereals, peas, beans, grains and spices were extended by ozone treatments above 5, 5, 5, 0.5, and 50ppm, respectively.