Influence of Solar Radiation and Microwave Heating on Microbiological, Chemical and Sensory Quality of Fresh Khoa

In a maiden attempt in utilizing solar radiation in dairy product preservation, the solar radiation was passed on to khoa through some media in order to extend its shelf life under room temperature (32 to 37°C). Similarly, application of microwave heating technique for the same purpose was also tried. Influence of the solar radiation through plain glass (S₁) and convex lense (S₁) and microwave heating powers (ranging from 40% to 60%) for 60 sec to 80 sec) on microbiological, chemical and sensory qualities of the fresh khoa was studied. The mean Standard Plate Count (SPC), Yeast and Mould Count (YMC) and spore count of fresh khoa (day-0) ranged from 0 to 4.33×102, 0 to 11.66 and 0 to 9.67 cfu/g. The chemical and sensory qualities of the samples remained almost similar (8.5 points out of 9) of control (8.6 point) The application of microwave heating was observed to be quite superior in reducing the SPC, YMC, and spore count of the khoa samples.