Dual Valorization of Garlic Cloves and Peels into Functional Honey-Garlic Candy and Biodegradable Edible Film

Abstract

Growing interest in the comprehensive use of functional ingredients and food waste has been driven by consumer demand for natural, health-promoting, and environmentally friendly products. This study aimed to develop a honey-infused candy using garlic bulbs and an edible film incorporating garlic peel waste, and to evaluate the physicochemical properties and biological activities of the resulting product for use as an enriched food with health-promoting benefits. Honey-infused garlic candy was prepared using three honey concentrations: 40%, 50%, and 60%. The physicochemical and sensory properties of the developed candies were evaluated. Garlic peel extract was incorporated into a gelatin–starch-based edible film containing glycerol and clove essential oil. The developed films were characterized for moisture content, thickness, water activity, microbial load, antioxidant activity, degradability, and surface morphology using Scanning Electron Microscopy (SEM). The formulation with 60% (HIGC) honey exhibited superior nutritional quality, higher protein content, and reduced water activity, indicating improved shelf stability and consumer acceptability. The developed film displayed increased moisture content and thickness but lower water activity and microbial load, along with high antioxidant activity. Surface morphology (SEM) showed a heterogeneous, micro-porous structure, confirming effective incorporation of garlic peel extract. Among the candy formulations, the 60% HIGC showed lower water activity (0.64 ± 0.00), lower browning index (2.2 ± 0.2), and higher protein (3.6 ± 0.0%), fat (0.4 ± 0.0%), and ash content (38.8 ± 0.2%) compared to the other formulations. Sensory evaluation indicated that the 60% HIGC received the highest scores for appearance (8.0 ± 0.1), taste (8.1 ± 0.1), and overall sensory preference (8.0 ± 0.1). The garlic peel-based edible film exhibited a moisture content of 21.7 ± 1.6%, a thickness of 0.09 ± 0.00 mm, a lower water activity (0.55 ± 0.01), a reduced microbial load (8.6 ± 12.5 CFU/g), and a higher antioxidant activity compared to the control film. SEM analysis revealed a compact, relatively uniform film structure, while degradability studies confirmed the biodegradability of the developed films. The study demonstrates a feasible dual-valorization approach for garlic cloves and peels in the development of functional food and biodegradable edible films, supporting sustainable utilization of agricultural by-products. Taken together, these studies illustrate an integrated approach to using garlic to enhance the functional value of food and to convert processing waste into environmentally acceptable packaging, thereby fostering sustainable food systems aligned with UN SDGs 3, 9, and 12.