Journal of Food Processing & Technology

Abstract

Osmotic Dehydration of Garden Egg (Solanum aethiopicum): The Shrinkage and Mass Transfer Phenomena

DK Adekeye*, OI Aremu, OK Popoola, EO Fadunmade, IS Adedotun and AA Araromi

Osmotic dehydration is usually employed to lower the water activity of fruits and vegetables and thus has a wide range of applications in food preservation. This study investigates the osmotic dehydration of garden egg (Solanum aethiopicum) using sodium chloride solution (NaCl) of varying concentrations (20, 40 and 60)% w/w as osmotic solutions. Different parameters such as percentage water loss (%WL), weight reduction (%WR) and solid gain (%SG) were investigated at different solution temperature (25, 35, 45, 55, and 65)°C, agitation time (20, 40, 60, 80, 100, 120, 140, 160 and 180) min and osmotic solution concentration (20, 40 and 60)% w/w to ascertain the optimum dehydration performance of the process. The performance efficiency of the process was evaluated at different osmotic solution concentrations (20, 40 and 60)% w/w with respect to time (20-180) min at a constant temperature of 40°C. The performance efficiency of the process was also evaluated at different osmotic solution concentrations (20, 40 and 60)% w/w with respect to temperature (25, 35, 45, 55, and 65)°C at the constant time (180 min). The results of this study showed that %SG and %WL increased with increase in concentration with respect to time whereby the optimum values for these parameters being 157% and 45.80% respectively were achieved at 60% w/w osmotic solution concentration, while optimum %WR (34.70%) with respect to time was achieved at 40% w/w osmotic solution concentration. Therefore, the order of %SG and %WL by the garden egg with respect to time was (60>40>20)% w/w. The optimum %SG, %WL, and %WR were achieved at 65°C in 60% w/w osmotic solution with the values of (133, 53.11 and 40.10)% respectively. The results from this study, therefore, showed that osmotic dehydration could potentially reduce the water activity of the garden egg.

Published Date: 2019-12-28; Received Date: 2019-12-03