Valorizating non-aesthetic waste food to achieve zero hunger: thermal characterization and genetic algorithm for optimum flash drying of vegetables from a sustainable development goals perspective

Abstract Non-aesthetic wasted garlic from local markets is investigated for flash drying, aiming at waste food upgrading within circular economy principles. 1D wasted garlic flash drying model is developed, envolving the garlic thermal properties. Hence, thermal conductivity and heat capacity were experimentally investigated using MTPS and DSC techniques, respectively, in the temperature range of [30–100 °C] and moisture content of [5–20 %]. Regression models were then developed to correlate the properties to the variables. Experimental results showed that thermal conductivity and heat capacity varied in the range of 0.06–0.318 W/m °K and 1.6–2.05 J/g. °K, within a satisfatory experimental error of 2 % and 5 % respectively. The sensitivity analysis showed that the air temperature, initial moisture content and particle flow are the main variables. Using Genetic Algorithm, optimal drying conditions were identified to achieve a 2 % final moisture content. This configuration improved drying efficiency, reducing final moisture content by 52 % and increasing the drying rate by 33 %.