Heat Penetration Studies

Kadhi, an ethnic fermented food is popular is most parts of India, but has very short life at ambient temperature. A long shelf life kadhi (prepared by cooking lactic fermented milk with gram flour and spices) was developed by retort processing of the product. Kadhi was packed in retortable pouches and subjected to heat treatment of F0 = 3.0 and F0 = 5.0. The ‘Come-up'' time required in kadhi heat treated to F0 = 3.0 to attain retort temperature of 115°C was 6 min whereas that in case of heat treated to F0 = 5.0, it was 12 min. The corresponding ‘Process – time'' were 27.25 and 48.11 min. and cook values were 58.48 and 99.52 min respectively. These values indicated the more energy requirement for kadhi for heat treating at F0 = 5.0. No significant differences in the sensory & chemical parameters between the two heat treated samples was observed. The studies indicated that the heat treatment of F0 = 3.0 was sufficient to give a shelf life of more than 6 weeks at 37°C storage. This study should help shed some light on the convenience food sector and should be especially useful to professionals in the food processing industry.