Effect of sequential-combined solar energy assisted hot air and hot air assisted radio frequency drying on the physical and chemical properties of dried apricots.

Quality characteristics of sulphured and non-sulphured apricots dried with a sequential combined pilot scale solar assisted hot air and hot air assisted radio frequency dryer and conventional sun system were compared. The combined drying approach showed improved color, hardness, antioxidant activity and retention of vitamin C, β-carotene and total phenolic content values compared to conventional sun drying both for sulphured and non-sulphured samples. The effects of sulphur concentration and addition of pistachio hull extract as a treatment prior to drying were also investigated.

Hot air-assisted radio frequency drying of apricots: Mathematical modeling study for process design.

Conventional hot air and solar energy processes have been used for apricot. These processes had adverse effects on the quality due to the longer process times, and this indicates the need for an innovative approach. Radio frequency (RF) processing has innovation potential for drying with its volumetric heating feature, but an optimal process should be designed for process efficiency in industrial-scale applications.

Spray drying of liquorice (Glycyrrhiza glabra) extract.

The objective of this work was to study the influence of spray drying conditions on the physicochemical properties of liquorice (Glycyrrhiza glabra) extract. The stickiness and hydroscopicity problems in the power were overcome by use of dextrose equivalent (DE12) and DE19 maltodextrins as drying agents. The inlet air temperatures of 110 °C, 120 °C, and 130 °C and maltodextrin concentrations of 10 %, 15 %, and 20 % (maltodextrin dry solids/100 g feed mixture dry solids) were the independent variables.

Effect of drying methods on the moisture sorption isotherms and thermodynamic properties of mint leaves.

Mint leaves were dried by three different types of dryers, namely; tray, freeze and distributed (indirect)-type solar dryer. Sorption isotherms of fresh, solar, tray and freeze dried mint were determined at temperatures of 15 °C, 25 °C and 35 °C over a range of relative humidities (10-90%). The effect of drying method on the water sorption isotherms of dried mint samples was evaluated.