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Strawberries were osmotically dehydrated prior to microwave‐vacuum drying. Drying kinetics were presented in terms of the temperature of the product during drying, drying curve and drying time. Thin‐layer models of Lewis, Henderson and Pabis, and Page were fitted with the observed data. The root mean square error and the coefficient of determination (r2) were used to evaluate the fit of the models. The effects on quality of dried strawberries were evaluated for various drying parameters such as: with or without osmotic treatment, input power levels (1 W/g and 1.5 W/g) and power modes (continuous, 45 s on/15 s off, 30 s on/30 s off). The effects were evaluated by a standard factorial (2 × 2 × 3) analysis in triplicate. The quality aspects were studied in terms of water activity, shrinkage, rehydration capacity, texture, color and sensory evaluation. The results showed that the osmotic pretreatment did not help in terms of drying time and energy saving but provided a better quality of dried product. Page's model presented the best fit for the observed data. PRACTICAL APPLICATIONS The objective of this research was to provide predictive equations and determine the drying kinetics for osmotically dehydrated microwave‐vacuum dried strawberries. The goal was to optimize the drying conditions in terms of energy requirement and product end quality.

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Background and objectives Upland rice has unique quality derived from diverse growing environment; however, little is known about rice quality cultivated in the uplands of South‐East Asia region. Four highly consumed upland rice varieties are determined their important physical qualities and microstructures. Findings All four upland rice varieties exhibit different visual appearance and physical quality especially for color, sphericity, and bulk density of rice grain, and viscosity (peak viscosity ranges from 931 to 3,113 cP; p ≤ .05) of rice flour. Each variety reveals unique structure of aleurone layer and starch granule wherein the granule size and arrangement are notably different among the four varieties. Conclusions Physical quality and microstructure are the key features for identifying rice variety cultivated in upland area of Thailand. Significance and novelty The four varieties of Thai upland rice grains exhibit different macro‐ and microstructure that are considered a helpful index for variety identification, postharvest handling, and utilization of rice flour.

Heating is an important treatment before protein extraction process. Rapid heating of microwave heating (MW) was investigated to compare with hot air oven (HA) heating prior to protein extraction in soybeans. Heating temperature was controlled at 50°C, with the heating time of 15, 30, 45, 60 and 75 min. The control treatment was no heat treatment. The treated samples were analyzed i) the total protein using Kjeldahl method, ii) the protein soluble by Bradford method and iii) cells microscope investigated by scanning electron microscope (SEM). The results were found that the pretreatment of 75 min microwave (MW75) heating provided the highest protein with the amount of absorbance value and total protein of 3.0365 ± 0.004 mg mL-1 and 3.70 ± 0.01% respectively. The lowest protein extraction of 2.7707 ± 0.020 mg mL-1 and 3.38 ± 0.005% total protein value occurred in the condition of 15 mines hot air oven (HA15) heating. The investigation using scanning electron microscope (SEM) revealed that protein extraction correlated with the enlargement and breakage of cell wall and endosperm caused by microwave heating rather than hot air oven heating. The rapid heating of microwave and heating time influenced the amount of extracted protein. Keywords: Soybean, Protein, Microwave, Hot air, Heating

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