A five level four factors central composite rotatable design under response surface methodology was used to optimize process conditions of the foam mat drying process i.e. egg albumen (0%-12%), methyl cellulose (0.1%-0.5%), drying bed thickness (3-7 mm) and drying temperature (55-75°C) to develop grape bar with final moisture content of 14%±1% (dry-base). Contour and response graphs were genera...

The drying of hydrogel films formed by Poloxamer 407 poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) amphiphilic block copolymer was investigated at various air relative humidity (RH) conditions ranging from 11 to 97%. Initially, the amount of water lost increased linearly with the drying time. After this linear region (stage I), a nonlinear behavior was observed (stage II). The...

Convective air drying characteristics of mango slices at different drying temperatures (60°C, 70°C and 80°C), at an air velocity of 0.5 m/s and for constant sample thickness (3 mm) were investigated. Results indicated that drying took place in the falling rate period. Drying time decreased considerably with increased drying temperature. Three mathematical models; namely, Newton (Lewis), Henders...

microwave assisted fluidized bed drying is a novel drying technique which reduces drying time and yields higher quality products. in this study the effect of this method on color changes of whole and cut hazelnut kernels was investigated. the parameters of color and resulting total color change, chroma, hue angle and browning index were also calculated during drying in three temperatures (40, 5...

Gentle in-store drying of popping corn may reduce the risk of stress fissures being generated, an effect which reduces popcorn expansion volume. In order to allow optimisation studies of in-store drying to be conducted, thermophysical properties of two current Australian popping corn varieties were measured in the range 30-50°C, at moisture contents from 12% to 20% wb. Models were developed for...

In this work, we tried to evaluate mass transfer during a combined infrared-vacuum drying of kiwifruits. Infrared radiation power (200-300 W) and system pressure (5-15 kPa), as drying parameters, are evaluated on drying characteristics of kiwifruits. Both the infrared lamp power and vacuum pressure affected the drying time of kiwifruit slices. Nine different mathematical models were evaluated f...

This study was conducted to investigate the effect of blanching treatment (98 °C for 3 and 6 min) and air drying temperature of 40, 50 and 60 °C on the thin layer drying characteristics such as drying time, drying rate constant, effective moisture diffusivity and activation energy, as well as on anthocyanin content of black carrot shreds. It was observed that drying temperature affected the dry...

Optimization of the cereals drying operation requires a model containing the operating variables for dryers. Modeling of grain dryer is still uncertain since the drying process is unpredictable and relies on empirical parameters. The paper present the main mathematical models proposed in the last years for describing the drying phenomena. The main objective is to develop a model that would desc...

A domestic solar dryer with transparent external surfaces was designed, built and tested. Thin-layer drying models that describe the drying phenomena in a unified way, regardless of the controlling mechanism; have been used to estimate the drying period for several products. Temperature of the drying medium is one of the factors that affect the drying rate constant of the exponential model. Thi...