Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution

• Published in: Chemical Industry and Chemical Engineering Quarterly 2015, Vol.21 (4), p.485-492
• Main Authors: Pavelkic, Vesna, Brdaric, Tanja, Petrovic, Marija, Sekularac, Gavrilo, Kosevic, Milica, Pezo, Lato, Ilic, Marija
• Format: Article
• Language: English
• ISSN: 1451-9372; 2217-7434
• DOI: 10.2298/CICEQ141014004P

The applicability of Peleg?s model was investigated for predicting mass transfer kinetics during osmotic dehydration (OD) process of pears, at different concentrations (40%, 60% and 70% w/w) and temperatures (20?C, 35?C and 50?C) of sucrose solution. Increase in sucrose solution concentration resulted in higher water loss (WL) and solid gain (SG) values through the osmotic treatment period. After 360 minutes of osmotic treatment of pears, WL ranges from 23.71 % to 31.68 % at 20?C, from 24.80 % to 40.38 % at 35?C and from 33.30 % to 52.07 % at 50 ?C of initial weight of pears. The increase of dry mass of the samples, SG, after 360 minutes of osmotic treatment ranges from 3.02 % to 6.68 % at 20?C, from 4.15 % to 7.71 % at 35?C and from 5.00 % to 8.92 % at 50?C. Peleg?s rate constants k1WL and k1SG, decreased with increasing temperature, as well as decreased with increasing concentration of osmotic solution at constant temperature. Both capacity constants k2WL and k2SG also exhibits the inverse relationship between capacity constant and temperature, as well as concentration of the osmotic solution. The Peleg?s rate constants for WL and SG at all temperatures followed Arrhenius type relationship. The model predicted equilibrium values were very close to experimental ones, which is confirmed with high coefficients of determination and by the residual analysis.