​Physico-chemical and Organoleptic Properties of Intermediate Moisture (IM) Slices from Pineapple [Ananas comosus (L.) Merr.

Abstract

Background: Pineapple is produced round the year in the tropics and therefore, market gluts are very common and post harvest losses of around 20-30% are reported. Intermediate Moisture Fruits (IMF) have a water activity ranging between 0.65-0.90 and moisture content of 15-40%. Hence, the present study was undertaken to develop intermediate moisture fruit slices by evaluating the effect of various osmotic agents and pineapple varieties on the physico-chemical and organoleptic qualities of the product. Methods: Pineapple varieties ‘Mauritius’, ‘Kew’ and ‘MD-2’ were selected for the study. Fruit slices were steam blanched, followed by immersion in osmotic solutions (fruit : solution ratio of 1: 4), containing six different osmotic agents viz. sucrose, sucrose+sorbitol, glucose syrup, sucrose+NaCl, palm sugar and honey separately, in combination with 0.5% ascorbic acid and 0.25% potassium metabisulphite, for six hours and were subsequently dehydrated at 50°C in a tray dryer. Result: Moisture content varied between 19.42 and 29.71% and water activity values in between 0.60 and 0.73.Decline in L* and b* values with a corresponding increase in a* value was observed in IM slices. Intermediate moisture pineapple slices had ascorbic acid content in the range of 17.64 to 200 mg 100 g-1.