Thermal Treatment of Cottage Cheese “In-Package” by Microwave Heating1

Small-curd cottage cheese was packaged in polystyrene tubs and subjected to heat treatments of 37–82.2°C using .5 and 2.8 kw microwave sources. Cottage cheese was also packed in flexible pouches (laminate structure of ethylene vinyl acetate/polyvinylidene chloride/ethylene vinyl acetate - EVA/PVDC/EVA) and polyethylene tubs and subjected to heat treatments of 37.0 – 82.2°C. Moisture content, syneresis, microbial population, pH and sensory properties were monitored until samples were considered no longer acceptable. The shelf life of samples ranged from 7 to 42 d. Optimum quality was observed when the packaged cheese was heated to 48.8°C using the low power source. Cheese packed in the flexible pouches had the longest shelf life.