Studies on the Chemical and Sensory Properties of Jam from Osmotically Dehydrated Pineapple Slices

Abstract

Dried fruits have limited food use, this study explored the food utilization potential of dehydrated pineapple slices. The influence of 50 °Brix sugar and 47:3 % w/w sugar/salt solutions on the quality of jam produced were investigated. Pineapple slices were osmotically dehydrated (4 hr), oven dried (60 ℃ 27 hr), and rehydrated at 90 ℃ for 15 min and at room temperature (RT) for 6 hr. Jams were made from dried pineapple slices (with or without osmotic dehydration), fresh pineapple and compared with commercial pineapple jam. Chemical and sensory properties of the jam were conducted. Osmotic dehydration contributed to the titratable acidity values, rehydration temperature had no significant (P<0.05) effect on total soluble solid of the samples dehydrated in sugar/salt solution, also the moisture content increased as the rehydration temperature was increased. Osmotic dehydration of fruits prior to drying had effect on the retention of the vitamin C and protected reducing sugar from being lost. Panelist revealed that jam samples produced from pineapple dehydrated in sugar solution and rehydrated at room temperature were most preferred. The results suggest that surplus fruits can be preserved by osmotic dehydration followed by oven drying for later use in jam production.