In this study, the effects of osmotic dehydration pre‐treatments in sucrose solutions on dried Kosia pear slices were determined. The effective diffusion, modeling, color, rehydration, specific energy consumption, specific moisture extraction rate (SMER), evaporation latent heat, energy efficiency (EE), convective heat (hc), and mass transfer coefficient (hm) parameters of fruit slices were investigated. The shortest drying time (17 h) was observed in the drying process of the samples subjected to osmotic dehydration in 25% sucrose solution for 1 h. The best thin‐layer drying models were identified as Lewis (R2: .9977) and Jane‐Das (R2: .9977) models. Effective diffusion values ranged between 2.13–4.94 × 10−5 m2 s−1. Rehydration ratios ranged between 2.09 and 2.71 g g−1 while rehydration capacities ranged between 57.24% and 63.05%. The least color change was observed in control samples. SMER values of the dried samples ranged between 0.0062–0.00011 kg kWh−1. EE values ranged between 4.19% and 0.03%. Mass transfer coefficient values varied between 1.57 × 10−8 and 1.06 × 10−12 m/s. Heat transfer coefficient value was calculated as 5.773 × 10−7 W m−2 K. Uncertainty that stems from measurements and cannot be controlled was calculated as ±2.324%. Novelty impact statement High sucrose solution ratios of drying pre‐treatments reduced the drying time of Kosia pear slices. Control samples retained their color values better. Samples subjected to osmotic dehydration in 25% sugar solution for 1 h had is the optimum values drying performance and energy parameters.

Bu çalışmada alıç meyvesi sıcaklık kontrollü bir mikrodalga kurutucuda kurutularak kuruma süresi, renk değeri ve ürünün kuruma eğrilerini en iyi tahmin eden matematiksel model belirlenmiştir. Ürünler tasarlanan sıcaklık kontrollü mikrodalga kurutucuda 50, 60 ve 70ºC sıcaklıklarda kurutulmuştur. Kuruma süreleri 50, 60 ve 70ºC kurutma sıcaklıkları için sırasıyla 129, 66, ve 45 dakika olarak belirlenmiştir. En kısa kuruma süresi 70ºC kurutma sıcaklığında olurken en uzun kuruma ise 50ºC kurutma sıcaklığında olmuştur. Kuruma eğrilerini tahmin etmek için ince tabakalı kurutma modellerinden Yağcıoğlu, Midilli-Küçük ve Page matematiksel modelleri kullanılmıştır. Kuruma eğrilerini en iyi tahmin eden matematiksel modelin Midilli-Küçük modeli olduğu belirlenmiştir. Ayrıca taze ve kurutulmuş alıç meyvesinin kalite kriteri olarak renk değerleri araştırılmıştır. L parlaklık ve a kırmızılık renk değerleri açısından her üç kurutma sıcaklığında da kurutulan ürünler ile taze ürün arasında istatistiki açıdan bir farklılık oluşmuştur. b sarılık değeri açısından ise istatistiki olarak 50 ve 70ºC sıcaklıkta kurutulan örneklerle taze ürün arasında bir farklılık oluşmamıştır. Taze ürünlere ait hesaplanarak belirlenen kroma, hue açısı ve esmerleşme değerleri ile kurutulan ürünlere ait kroma ve esmerleşme değerleri arasında ise rakamsal olarak büyük bir farklılık yoktur. Ancak taze ürünün kroma ve kahverengilik değerlerine en yakın değerler 70ºC kurutma sıcaklığında yapılan kurutma işleminde belirlenmiştir. In this study, the hawthorn fruit was dried in a controlled temperature microwave dryer and determined the mathematical model that best predicts the drying time, color value and product drying curves. Since the horticultural fruit contains important nutritional values, when it is desired to be dried and consumed, optimum drying conditions should be determined. Productions were dried in a temperature controlled microwave dryer under at temperatures of 50, 60 and 70ºC. Drying times lasted 129, 66, and 45 minutes for drying temperatures of 50, 60 and 70ºC, respectively. The shortest drying time was at a drying temperature of 70ºC, while the longest drying is at a drying temperature of 50ºC. The Yağcıoğlu, Midilli-Küçük and Page's mathematical model were used to predict the drying curves, and Midilli-Küçük model was determined as the best model to predict the drying curves. In addition, the color values of fresh and dried hawthorn fruit as a quality criterion were investigated. In terms of L brightness and a red color values, there was a statistically significant difference between dried and fresh products at all three drying temperatures, while there was no statistically significant difference between fresh and dried products at temperatures of 50 and 70ºC in terms of b yellowness value. The chroma, hue angle and brown values of the fresh products and chroma and brown values of the dried products are not differentiating from each other numerically. However, the values closest to the fresh product's chromium and brown values were determin...

The present study potato slices were dried at a microwave oven and  hybrid (microwave + convective) oven at PR 3 power rate. Effects of drying methods and conditions on surface temperature profile, drying characteristics, effective diffusion, activation energy, thin-layer drying model, specific moisture extraction rate (SMER), specific energy consumption (SEC), energy efficiency (EE), specific exergy loss (SEL), exergy efficiency (EXE), specific heat, thermal diffusivity, thermal conductivity and density were investigated. The lowest surface temperature (39.00 ºC) was observed in 160 W+55 ºC drying treatment and the greatest (128.30 ºC) in 160 W+75 ºC drying treatment. Among the thin-layer drying models, Wang-Sing model was identified as the best model. Effective diffusion values of drying treatments varied between 1.14x10-7- 3.18x10-10, activation energy values between 79.12 kJ/mol (Microwave) and 126.96 kJ/mol (microwave + convective), SMER values between 1006.57 - 1950.14 kg water/kWh, SEC values between 8.86 - 14.31 MJ/kg water, EE values between 2.55 - 19.39%, SEL values between 0.42 - 12.68 kJ/kg. Of thermophysical properties of potato slices, specific heat values varied between 837.69 - 848.13 J/kgºK, thermal conductivity values between 0.07 - 0.27 W/mºK, thermal diffusivity values between 1.163 - 3.774x10-6 m2/s and density values between 700.60 - 839.41 kg/m3.

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In this study, the plant node was dried in an oven (40, 50 and 60 °C), shade and temperature-controlled microwave (40, 50 and 60 °C) methods. Statistically (p < 0.05), the values closest to the color values of fresh grass were determined in an oven at 40 °C drying temperature. Effective diffusion values varied between 8.85 × 10 À 8 -5.65 × 10 À 6 m 2 s À 1 . While the activation energy was 61.28 kJ mol À 1 in the oven, it was calculated as 85.24 kJ mol À 1 in the temperature-controlled microwave. Drying data was best estimated in the Midilli-Küçük (R 2 0.9998) model oven at 50 °C. The highest SMER value was calculated as 0.0098 kg kWh À 1 in the temperature-controlled microwave drying method. The lowest SEC value in the temperaturecontrolled microwave was determined as 24.03 kWh kg À 1 . It was determined that enthalpy values varied between À 2484.66/ À 2623.38 kJ mol À 1 , entropy values between À 162.04/ À 122.65 J mol À 1 and Gibbs free energy values between 453335.22-362581.40 kJ mol À 1 . Drying rate values were calculated in the range of 0.0127-0.9820 g moisture g dry matter À 1 in the temperature-controlled microwave, 0.0003-0.0762 g dry matter À 1 in the oven, and 0.001-0.0058 g moisture g dry moisture matter À 1 in the shade. Phenolic content 6957.79 μg GAE g À 1 fw -48322.27 μg GAE g À 1 dw, flavonoid content 3806.67 mg KE L À 1 fw -22200.00 mg KE L À 1 dw and antioxidant capacity 43.35 μmol TE g À 1 fw -323.47 μmol TE g À 1 dw. The highest chlorophyll values were obtained from samples dried in an oven at 40 °C. According to the findings, it is recommended to dry the knotweed (Polygonum cognatum Meissn.) plant in a temperature-controlled microwave oven at low temperatures. In this study, in terms of drying kinetics and energy parameters, a temperature-controlled microwave dryer of 60 °C is recommended, while in terms of quality characteristics, oven 40 °C and shade methods are recommended.