Dual Control of 3-Mcpd Esters in Vegetable Oils: Formation Pathways Modulated by Storage, Heat, Chlorides, and Mitigation Via Antioxidant and Mesoporous Silica Nanoparticle

Abstract

This study investigated 3-monochloro-1,2-propanediol (3-MCPD) ester dynamics in vegetable oils under room-temperature storage, thermal processing, and chloride supplementation. Prolonged storage (>6 months) significantly accelerated 3-MCPD ester formation (80.8–190 μg/kg·month−1), exceeding initial 6-month accumulation rates (15.2–71.9 μg/kg·month−1), thereby elevating contamination risks despite levels remaining below EU Regulation 2023/915 limits. Thermal processing induced a dynamic equilibrium between 3-MCPD ester synthesis and degradation, modulated by oil-specific thermal stability. CaCl2 supplementation generated the highest 3-MCPD ester levels (2189 μg/kg) compared to NaCl and KCl, with metal cations (via coordination capacity, charge density, and ion-pair effects) critically influencing nucleophilic substitution pathways. Antioxidants mitigated ester formation by suppressing lipid oxidation and epoxonium radical reactions, though efficacy depended on thermal stability and dispersibility. Mesoporous silica nanoparticles (MSNs) achieved 98% adsorption removal, demonstrating potential for industrial application in oils and lipid-rich foods. Combined antioxidant and MSN strategies offer practical solutions for reducing 3-MCPD ester exposure.

Keywords: Formation, Mitigation, 3-MCPD esters, storage, Thermal processing