Osmo-convective dehydration of pineapple cubes using jaggery and coconut sugar as non-conventional osmotic agents

Abstract

This study evaluates the suitability of unconventional natural sweeteners as an alternative to sucrose for pineapple’s osmotic dehydration (OD). This study focused on the mass transfer kinetics and the quality attributes of pineapple cubes treated with five different osmotic solutions, i.e., sucrose, jaggery, coconut sugar, sucrose-jaggery, and sucrose-coconut sugar mix. The concentration of solutes (60°Brix), sample-to-solution ratio (1:2), immersion time (5 h), and process temperature (room temperature) were kept constant for all the treatments. The evaluation of mass transfer kinetics was performed at an interval of 1 h by fitting the experimental data of water loss (WL), solid gain (SG), and weight reduction (WR) in the Peleg model (R² = 0.91 to 0.98). WL, SG and WR increased with the increasing immersion time. The combined mixture of two solutes (sucrose and jaggery) was found to be the best osmotic agent in terms of water loss (32.3%) and weight reduction (24.9%). Using coconut sugar instead of sucrose had little influence on osmo-dried pineapple cubes except for rehydration ratio (1.83), shrinkage (71.75%), and color responses. Sucrose and coconut sugar-treated cubes retained ascorbic acid at an acceptable level of 29.61% and 28.007%, respectively. A substantial impact on the sensory attributes of pineapple cubes was observed by introducing new and healthy sweeteners as osmotic agents. Replacement or combination of sucrose (conventional sweetener) with natural sweeteners like jaggery and coconut sugar could be an excellent strategy for decreasing unhealthy sucrose consumption.