Modeling of pomegranate arils drying was carried out under thin layer near‐infrared (NIR)‐vacuum conditions. Drying of the samples was implemented at the absolute pressures of 2, 20, 40 and 60 kPa and drying temperatures of 60, 70, 80 and 90C. Drying behavior of pomegranate arils as well as the effect of drying conditions on moisture loss, effective diffusion, activation energy, shrinkage, color and energy consumption, dried in NIR‐vacuum dryer are discussed in this study. Results showed that the Aghbashlo model had supremacy in prediction of pomegranate arils drying behavior. Effective moisture diffusivity of the samples was estimated in the ranges of 3.07 × 10−10 to 1.14 × 10−9 m2/s. Activation energy were computed between 30.80 and 37.48 kJ/mol. Minimum shrinkage (71.46%) and color difference (16.7%) were achieved at temperature of 60C and absolute pressure of 2 kPa. Energy consumption was estimated in the ranges of 0.206 to 2.072 kWh. Practical Applications Combining NIR with vacuum condition can be a novel method in drying of pomegranate arils. Advantages of this method are high mass transfer coefficients and high quality. NIR radiation energy is absorbed by the surface grain molecules and directly penetrates under the surface into the product. This phenomenon led to the rapid heating of water inside the material. Also, vacuum drying is a potentially useful technique to improve quality as well as nutritional value. Combination NIR with vacuum creates fast and quality method for thin‐layer drying. Monitoring of pomegranate arils can be easily controlled and the aril characteristics can be measured easily. Pomegranate is known as a medicinal plant. Pomegranate arils are used in medicine to cure heart and vascular disease, preventing cancers and blood purification. The dried arils using NIR‐vacuum were preserved for relatively long time and save minerals and vitamins.

Nectarine (Prunus persica) is smooth-skinned peach of the rosaceae family, known for more than 2000 years and grown throughout the warmer temperate regions of both the northern and southern hemispheres.In tree shape and leaf characteristics the peach and nectarine are indistinguishable, but nectarine fruits look more like plums than peaches because of the smooth skin. The stones and kernels of the two fruits are alike in appearance. Nectarines have red, yellow or white fl esh and source of fi ber, iron, calcium, magnesium, phosphorus, zinc, copper, glucose and vitamin B 1 , B 2 , B 3 , B 6 , C and E (Balch, 2003). Nectarine is one of MODELLING OF NECTARINE DRYING UNDER NEAR INFRARED -VACUUM CONDITIONSBehnam Alaei, Reza Amiri Chayjan ABSTRACTBackground. Drying of nectarine slices was performed to determine the thermal and physical properties in order to reduce product deterioration due to chemical reactions, facilitate storage and lower transportation costs. Because nectarine slices are sensitive to heat with long drying period, the selection of a suitable drying approach is a challenging task. Infrared-vacuum drying can be used as an appropriate method for susceptible materials with high moisture content such as nectarine slices. Material and methods. Modelling of nectarine slices drying was carried out in a thin layer near infraredvacuum conditions. Drying of the samples was implemented at the absolute pressures of 20, 40 and 60 kPa and drying temperatures of 50, 60 and 70°C. Drying behaviour of nectarine slices, as well as the effect of drying conditions on moisture loss trend, drying rate, effective diffusion coeffi cient, activation energy, shrinkage, colour and energy consumption of nectarine slices, dried in near infrared-vacuum dryer are discussed in this study. Six mathematical models were used to predict the moisture ratio of the samples in thin layer drying.Results. The Midilli model had supremacy in prediction of nectarine slices drying behaviour. The maximum drying rates of the samples were between 0.014-0.047 g water /g dry material ·min. Effective moisture diffusivity of the samples was estimated in the ranges of 2.46·10 -10 to 6.48·10 -10 m

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