Determination the effects of hot air drying and microwave drying operations on the quality parameters and drying behavior of plum leather

Plum leather from the fresh fruits of japon variety. In production of plum leather, the plums were crushed and heating pressed by pulper. Afterwards, freshly prepared corn starch and sugar mixture was added to the boiling pulp. Cooked plum pulp?starch mixture was evenly spread, and the mixtures were dried by microwave dryer and hot air dryer. Plum leathers wrapped with baking papers and placed into lockable refrigerator bag, and then covered with aluminum foil to protect against external influences and stored for a period of 9 months. In order to determine the effects of processing methods and storage conditions various analyses were applied to samples at 3 month-interials. As a result, pH, TA, SS, total solids, water activity, total monomeric anthocyanins, anthocyanine degration products, color analyse, total phenolic contents, antioxidant activity, HMF, mineral content and sensory analysis were applied. Statistical evaluations showed that some processing applications and storage conditions significantly (p<0.005) affected color value of the plum leather samples. Plum leathers total monomeric anthocyanins and phenolic compounds amounts observed a decrease during storage. As expected, the value of HMF was observed to increase in the plum leathers during storage. Plum leathers samples were found to be rich in potassium content. Sensory evaluation of the most admired hot air-dried leather samples and microwave-dried leather samples were determined.