Physico-chemical, thermo-physical and energy consumption analyzes of carrot chips produced by osmotic drying method

Abstract

Abstract In present study, effects of drying methods (continuous and intermittent) and pre-treatments (dipping into 25% salt, 25% vinegar, 25% (salt + vinegar), 10% Pyracantha coccinea and 10% Malus floribunda solutions) on drying models, effective diffusion, dimensional traits, rehydration, color, shrinkage ratio, energy consumption, thermo-physical and some drying properties of carrot slices were investigated. Among the thin-layer drying models, Wang-Sing model yielded the best and Rational 1-parameter 2 model yielded the weakest estimations. Effective diffusion values varied between 2.96–9.12x10− 9 m2 s− 1 in continuous drying method and between 2.61–5.59x10− 9 m2 s− 1 in intermittent drying method. The greatest rehydration capacities were observed in samples dipped into 25% vinegar (82.88%) and 10% Malus floribunda (82.13%) solutions. The greatest volume change (92.60%) was observed in samples dipped into 10% Pyracantha coccinea solution and dried by continuous drying method. The lowest volume change (72.92%) was observed in control samples of intermittent drying method. In terms of chroma values, the samples dried by intermittent drying after dipping into 25% salt and 25% vinegar solutions yielded the closest values to the fresh samples. As an alternative drying method in terms of chroma value, dipping into 10% Pyracantha coccinea solution could also be selected in intermittent drying method. The greatest evaporation latent heat (ELH) value (10.62 kWh) was observed in samples dipped into 25% vinegar solution and the lowest ELH value (5.63 kWh) was observed in samples dipped into 25% (salt + vinegar) solution.