Natural Antioxidant Enrichment of Olive Pâté: Effects of Microencapsulated Bergamot By-Product Extract Levels on Quality and Storage Stability

Abstract

Olive pâté is a lipid-rich semi-solid product susceptible to oxidative deterioration during storage. This study investigated microencapsulated bergamot (Citrus bergamia) by-product extract (MBE) as a natural antioxidant for improving olive pâté stability. MBE, obtained by spray drying with 20% (w/w) maltodextrin, was incorporated at 2.5 or 5.0 g per 100 g of olives (OP2.5 and OP5), while a non-enriched formulation served as control (CTR). Samples were stored at 20 and 30 °C for 100 days and analysed for physicochemical, colour, phenolic, antioxidant, microbiological, sensory, and oxidative stability. Storage temperature and formulation significantly influenced quality evolution. At 30 °C, OP2.5 showed the lowest total colour difference after 100 days (ΔE* = 3.29 versus 5.05 for CTR) and the highest final DPPH radical-scavenging activity. Both enriched formulations exhibited longer Oxitest induction periods than CTR at day 0 (26.53 and 25.33 vs. 19.85 h) and after 100 days at 30 °C (22.30 and 21.50 vs. 16.45 h). Microbial counts remained low, while sensory profiling indicated limited rancidity development and preservation of the main sensory characteristics. MBE effects were not proportional to the amount added, with OP2.5 providing the most balanced performance. These findings support MBE as a promising clean-label ingredient for improving olive pâté stability.