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Graphical abstract 3D sliced moisture content profile (db) at the end of foam-mat drying process at air temperature of 70 °C, foam thickness of 4 mm, and ovalbumin concentration of 2%. Highlights • A computational tool to produce foam-mat dried lime juice powder was developed. • Effect of air temperature, foam thickness and ovalbumin concentration was assessed. • Uniform moisture and temperature distributions were achieved during the process. • Improvements in the powder's water absorption properties were obtained. • The developed methodology may be a suitable tool for industrial applications. Abstract Foam-mat drying has been recently welcomed as an effective technique since it lacks deficiencies that plague conventional methods such as long processing time. It is essential to apply appropriate and inexpensive drying methods for producing powders from heat-sensitive foods such as lime juice. Therefore, this study aimed to intensify the interaction effects of multi variables including ovalbumin concentration, foam thickness and air temperature to analyze their simultaneous interactions on quality characteristics during lime juice drying. The process was also modeled to study the effect of ovalbumin concentration, foam thickness and air temperature on moisture and temperature distributions. Results showed that an increase in ovalbumin concentration reduced the foam density while increasing its expansion, porosity and stability. Higher air temperature, ovalbumin concentration and foam thickness reduced water solubility index and increased water absorption index. Increasing temperature from 50 to 70 °C intensified the drying rate by 25.58%. Moreover, chroma index, hue angle and browning index decreased by increasing temperature. Model performance was evaluated by comparing experimental and model data (R2 = 0.911). In summary, the lime juice powders produced by foam-mat drying process yielded promising results in terms of product's color, water absorption, porosity and flowability, among other quality characteristics. [ABSTRACT FROM AUTHOR]

• Foam-mat drying is applied to encapsulate sorghum extract rich in proanthocyanidin. • The encapsulant consisted of whey protein isolate, xanthan gum, and Arabic gum. • Encapsulant formula was chosen to build the best foam quality to support the drying. • A mechanistic drying model was built to simulate the moisture distribution in foam. • The encapsulant formula and the model works well to be applied in the encapsulation. Foam-mat drying (FD) was applied to encapsulate red sorghum extract (RSE) rich in proanthocyanidins. A sufficient amount of whey protein isolate (WPI) to build the foam that supported the drying acceleration and a mechanistic model for process quantification were required to design FD precisely. This research investigated the WPI percentage necessary for creating the best foam-microstructure to accelerate the drying considering the foam properties profiles during whipping and built a mechanistic model to quantitatively describe the drying phenomena illustrating the moisture distribution in foam. The foam obtained by the best formula (10% of WPI, 15 min of whipping) was then dried at 40, 50, and 60 ℃ of temperature. A mechanistic model was developed considering intraparticle diffusion, liquid-gas mass transfer, and liquid-gas equilibrium, involving effective-diffusivities (D e f f) and gas-liquid mass transfer coefficient (K) as parameters. The parameters were solved numerically, illustrating drying phenomena at several temperatures. It was observed that the model proposed works well, and the value of D e f f and K was temperature-dependent, with the activation energy of 5.904 kJ/mol and 13.857 kJ/mol, respectively. The encapsulation reached the yield (wb) of 16.24 - 18.29%, the encapsulation productivity of 84.17 - 96.01%, and proanthocyanidin content in the product of 9.113–9.227 mg/g. [Display omitted] [ABSTRACT FROM AUTHOR]