Physicochemical Properties of Osmo-Dried Ma-Kiang (Cleistocalyx nervosum var. paniala) as Affected by Different Osmotic Solutions

Physicochemical properties of osmo-dried Ma-kiang ( Cleistocalyx nervosum var. paniala ) prepared by various osmotic solutions were investigated. Sucrose solution (60 and 70 °Bx) mixed with 1% citric acid (CA) and calcium chloride (CaCl 2 ) were used. Osmo-dried  Ma-kiang fruits were hot air dried at 60°C for 8 hr. Results showed that there were no significant differences in all samples with respect to color ( L *, a *, and b * values), moisture content, water activity, pH, total soluble solid, titratable acidity and ascorbic acid content ( p >0.05). However, hardness and firmness were significantly different ( p ≤0.05). When considering sensory evaluation, the highest hedonic score of overall liking was found in the 70°Bx sucrose solution containing 1% citric acid (70°Bx-CA) sample. Osmotic dehydration was could be used as the promising pre-treatment before hot-air drying, in which 70°Bx-CA was an appropriate osmotic solution that enabled improvement of the sensory quality of dried Ma-kiang fruits. Keywords : Cleistocalyx nervosum var. paniala , osmotic dehydration, osmotic solution, hot-air drying, physiochemical properties