In this study, we report an optimization study on fig foam composition and hot air/microwave‐assisted foam mat drying (FMD) at different conditions to produce fig powder. The effects of foam composition on foam stability and capacity were evaluated. The optimum ratio of fig, egg white, carboxymethyl cellulose, and maltodextrin was determined as 52.9, 28.9, 0.8, and 17.4% (wt/wt), respectively, targeting maximum foam capacity and minimum drainage volume, that is, maximum foam stability. The effects of drying methods and their conditions were investigated on the drying rate of fig foam and physicochemical properties of fig powder. Moisture content, water activity, particle and bulk properties, and hydroxymethylfurfural and total phenolic contents of FMD fig powder were analyzed to understand the effect of drying methods and conditions on the physicochemical properties of fig powder. Practical applications Although fig fruit is generally dried as a whole, the ready‐to‐eat foods in the food market are mostly in powder form. That is why the powdering fig fruit by an appropriate drying method is essential. In this study, we report the foam mat‐dried (FMD) fig fruit powder. The fig foam composition was optimized. The fig foam was dried through hot air and microwave separately. The results showed that the foam capacity and stability of the fig powder highly depend on the foam composition. Microwave drying method was found more efficient than the hot air in the sense of time. Besides, the higher foam thickness provided more hydroxymethylfurfural content in the fig powder. The drying method and conditions were found to be important to produce a high‐quality FMD fig powder.

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Herein we investigated the effects of homogenization rate, inlet, and outlet air temperatures on physical (moisture content, water activity, glass transition temperature, particle and bulk density, wettability, solubility, and color) and chemical (total and surface phenolic content, antioxidant activity and encapsulation efficiency) properties of spray dried encapsulated propolis. The moisture content of encapsulated propolis powder was ranged from 4.26 to 6.17% while, the water activity values of these were changed between 0.197 and 0.269. The moisture content and water activity of products was an upward tendency with increasing inlet air temperature and decreasing outlet air temperature. An increase in inlet air temperature and decrease in outlet air temperature led to an increase in the glass transition temperature which changed in range of 44.50 to 51.45°C. While the wettability time of encapsulated propolis powder was longer than 100 s, their solubility ranged from 82 to 95%. Propolis powder produced at high inlet and outlet air temperatures and low homogenization rate had higher antioxidant activity, total, and surface phenolic content. Encapsulation efficiency calculated based on total/surface phenolic content varied widely between 29.79 and 99.73%. Encapsulation efficiency results clearly demonstrated that the conditions of process variables were effective on the encapsulation process. Practical Applications Propolis is one of the valuable bee products due to its high phenolic content and antioxidant activity. In the current market, propolis is mostly presented as a food supplement in the form of liquid extract. Although the importance of propolis has been recognized by the food industry and consumers, the usage of propolis has been limited due to its bitter and unpleasant taste. Another limitation of propolis usage in food products is environmental factors and food process conditions due to easily loss of its antioxidant activity and phenolic compounds. Encapsulation technology could provide overcome these challenges and improve the usability and durability of propolis in food products as an ingredient. However, the success of an encapsulation process considerably depends on process conditions. Therefore the effects of the encapsulation process conditions of spray drying method on physicochemical properties of encapsulated propolis powder were investigated in this study.

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In this study, turkey breast meat samples were dried with hot air (60, 75, 90 C), microwave (180, 360, 540 W) and freeze (0.1, 0.15, 0.2 mbar) drying and parameters related to the drying kinetics of turkey breast meat were investigated. Although a constant drying rate was not observed for all drying methods, the drying process occurred only during the falling drying rate period. Microwave drying process times were lower than those of hot air and freeze drying because of volumetric heating. Drying times decreased by increasing temperature, power and vacuum pressure. Kinetic parameters were determined by using the semi-empirical models of 2. Fick's diffusion equation. Two terms, Logarithmic and Page models were found to be better for hot air, microwave and freeze drying, respectively. In addition, the effective diffusion coefficient values were found in range of 2.03-2.53 × 10 −10 , 27.89-103.96 × 10 −10 and 2.99-3.36 × 10 −10 m 2 /s for hot air, microwave and freeze drying, respectively. Effective diffusion coefficients increased in direct proportion with temperature, microwave power and vacuum pressure. The activation energy obtained by the modified Arrhenius equation were 7.481 kJ/mol to 6.043 W/g for hot air and microwave drying respectively. Practical Applications The drying kinetics behavior of foods is important for protecting the final product quality, determining the process method and optimizing the process parameters in the food industry. Despite the availability of many drying kinetics studies, meat products exhibit different behaviors during the drying process due to their structure and composition. The drying kinetics behavior of turkey breast meat with different drying techniques was investigated in this study. When the effective diffusion coefficient and activation energy data were considered, it was noticed that microwave drying provided a faster and more effective drying process. The moisture content and water activity values, which are very important especially for meat products, showed that freeze drying provided a more reliable product by reducing the moisture content and water activity of final product more than other drying methods.