Green valorization of avocado pits waste via intermittent pressurized liquid extraction: Phenolic profiling, antioxidant activity, and pH-dependent color stability of six Brazilian cultivars.

This study investigated intermittent process of pressurized liquid extraction (PLE) as a green strategy for recovering bioactive compounds from avocado (Persea americana) pits from six Brazilian cultivars (Breda, Fortuna, Geada, Hass, Margarida, and Quintal). Temperature was the most influential extraction parameter, with best conditions established at 150 °C, 4 min static time, and 105% of rinse solvent volume using pressurized ethanol. Pits from the Geada cultivar achieved the highest extraction yield (56.57%), whereas those from Breda cultivar exhibited the highest total phenolic content (27.64 mg GAE/g d.w). Antioxidant capacity varied significantly among extracts from different cultivars, with Breda pits extracts showing the highest activity (DPPH: 22.98, ABTS•+: 70.48, and FRAP: 19.08 µmol TE/g d.w). UHPLC-MS analyses revealed phenolic profiles dominated by vanillic acid, catechin and chlorogenic acid. Multivariate analysis demonstrated stronger correlations between antioxidant capacity and specific phenolic compounds (apigenin, catechin, and chlorogenic acid). Additionally, pH-dependent color stability highlighted the potential application of the extracts as natural colorants.