High-pressure homogenization enhances the physicochemical properties and extraction of broccoli leaf bioactives

Broccoli leaves, despite their rich bioactive content, are considered non-edible, thus wasted. High-pressure homogenization (HPH) is a non-thermal, water-based technique that is emerging as an alternative for processing agri-food waste. In this study, the effects of HPH (performed at 90 MPa) on the physicochemical and phytochemical properties of broccoli leaves were evaluated and compared to a conventional blending method. HPH-treated samples exhibited smaller, greener particles with evident cell disruption. In the serum, broccoli leaves treated with HPH showed higher concentrations of amino acids and monosaccharides. Additionally, methanolic extracts of HPH-treated samples presented greater contents of total phenolics, flavonoids, and glucosinolates, as confirmed by metabolomic analysis. A total of 201 compounds were annotated, with 22 uniquely detected in HPH-treated samples and 16 in blended ones. HPH-treated extracts also exhibited higher antioxidant activity, more than doubling the activity at all concentration ranges studied. Altogether, these findings indicate that HPH improves the physicochemical properties, bioactive compound extraction, and antioxidant capacity of broccoli leaves.