Lipid Oxidation in Spent Coffee Grounds: Mapping Critical Degradation Stages Across the Processing Chain

• Grant number: 25/28523-4
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: January 27, 2026
• End date: April 26, 2026
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Technology
• Principal Investigator: Kelly Johana Dussán Medina
• Grantee: Letícia Vicente Moreno
• Supervisor: Marianne Su-Ling Brooks
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Institution abroad: Dalhousie University, Canada
• Associated to the scholarship: 25/06057-1 - Opportunity assessment for the valorization of coffee grounds., BP.IC

Abstract

Lipid oxidation is a central degradation pathway affecting the technological, sensorial, and nutritional quality of coffee ground lipids, directly limiting their potential for high-value applications in food and bio-based industries. Spent coffee grounds (SCG) contain a significant fraction of unsaturated free fatty acids, which are highly susceptible to oxidative reactions during processing and storage. However, there is limited systematic evidence identifying which processing stages contribute most to oxidative deterioration. This project aims to map and quantify lipid oxidation across sequential stages of the SCG processing chain in collaboration with RFINE Biomass Solutions, determining the critical points that most compromise lipid stability. Representative samples will be collected after each operational step, including generation, transport, drying, grinding, and storage, and the extracted lipids will be characterized using standardized analytical methods (AOAC, AOCS, and Adolfo Lutz Institute). Primary oxidation will be assessed through Acid Value (AV), Free Fatty Acids (FFA), and Peroxide Value (PV), while secondary oxidation will be quantified via the p-Anisidine Value (PAV), enabling calculation of the total oxidation index (TOTOX). By comparing the magnitude of oxidative changes among stages, the study will identify the phase with the highest deterioration rate and determine the associated processing conditions that intensify lipid damage. The expected outcomes include a detailed degradation profile, the definition of critical oxidation points, and the proposal of targeted process interventions to minimize deterioration, improve lipid quality, and enhance the stability and value of SCG-derived ingredients. Overall, the project provides essential scientific and technological contributions to sustainable biomass valorization and supports the development of better processing protocols for the coffee industry. (AU)