Description

Prickly pear fruit contains approximately 91 moisture content (wb). Removal of water from product, to make it unavailable for microbial growth is one of the important principles used in food processing. The slices were pre treated by dipping them in 1 calcium chloride solution for 10 minutes to maintain the firmness. The pre treated slices were then dipped in sugar syrup of 50, 60 and 70 °Brix added with 0.1 citric acid, as preservatives in beakers having syrup to fruit ratio as 1:4, 1:6 and 1:8. The beakers were then placed in temperature controlled water bath at 40, 50, 60 °C and at room temperature for 5 hours. The weight reduction, water loss and sugar gain during osmotic dehydration were studied.. It was found that the weight reduction, water loss and sugar gain increased with temperature and concentration of sugar syrup. The weight reduction of prickly pear fruit slices were found to vary in the range of 41.45 to 70.54 after 5 hours of osmotic dehydration. The subsequent air drying experiments showed that the complete drying of osmotically dehydrated prickly pear fruit slices was took place in the falling rate period.