Irradiation of chewable tobacco mixes for improvement in microbiological quality.

Microbiological quality of chewable tobacco mixes traditionally known as "Gutkha" was studied. The microbiological analysis of 15 samples analyzed revealed high bacterial and fungal counts. The total viable counts were in the range of 1.8 x 10(4) to 7.2 x 10(4) CFU g(-1) and the yeast and mold count from 3.6 x 10(3) to 7.1 x 10(4) CFU g(-1). The proteolytic and lipolytic counts were 9 x 10(2) to 2.6 x 10(3) CFU g(-1) and 2.6 x 10(3) CFU g(-1), on an average, respectively. Lecithinase-positive Staphylococcus aureus was found in 2 of the 15 samples analyzed; the counts were up to 3.4 x 10(3) CFU g(-1). Coliform and Salmonella spp. were found to be absent. Aflatoxins B , B2, and G2 were found to be present in all the samples. These samples were exposed to gamma radiation (60Co) at 1-, 2-, 3-, 5-, 10-, and 25-kGy doses. The decrease in total viable count and fungal count was noticed with increase of radiation dose. The 3-kGy dose was observed to be the sterilization dose for Gutkha. At this dose no survival of organisms was noticed and no revival was observed during postirradiation storage at room temperature for 6 months.