Extraction of squalene from agro-industrial waste: a sustainable alternative to conventional sources Available to Purchase

Improper disposal of agri-food processing wastes, including vegetable peels and dairy residues, poses environmental pollution challenges. This study evaluates the potential of onion peels, garlic peels, and molten butter (ghee) residue – common food processing by-products – as sustainable, non-food sources for squalene extraction. Squalene, a valuable bioactive compound traditionally obtained from shark liver oil and edible plant oils, faces sustainability issues due to its reliance on primary food resources. Using Soxhlet solvent extraction followed by high-performance liquid chromatography analysis, squalene yields of 23.59 ± 0.04, 22.21 ± 0.02, and 10.21 ± 0.02 mg/kg were obtained from garlic peels, ghee residue, and onion peels, respectively. These results demonstrate that food industry waste streams can provide appreciable quantities of squalene, promoting waste valorisation and resource recovery. The study supports the integration of food waste management strategies with biochemical production to reduce environmental impact and conserve primary food materials.