Volatilomic Analysis in Peel, Pulp and Seed of Hass Avocado (Persea americana Mill.) From the Northern Subregion of Caldas by Gas Chromatography With Mass Spectrometry

Abstract

Volatilomics, a subfield of metabolomics, is crucial for studying food quality and safety, ecological interactions, and natural product discovery. It allows characterizing biological matrices to identify secondary metabolites with biological potential. This study aimed to characterize VOCs present in the peel, pulp, and seed of Hass avocado and to reconstruct their associated metabolic pathways using HS-SPME-GC–MS. Hass avocado samples from the northern sub-region of Caldas and commercial sources were analyzed. A 3D model of the fruit was used to define optimal sampling points. VOCs were extracted using HS-SPME, separated, and identified by GC–MS, and compared against spectral libraries for compound confirmation. A metabolic enrichment analysis was performed using the hypergeometric test and betweenness centrality to identify key biosynthetic pathways. A total of 87 VOCs were identified, with the seed showing the greatest diversity, dominated by terpenes. Metabolites such as bicyclogermacene, β-pinene, dodec-(5Z)-enyl acetate, cis-β-guaiene, α-cadinene and δ-cadinene had the greatest influence on the variability between samples. Sensory profiles related VOCs to aromatic traits: peel herbaceous, woody and sweet notes, pulp fatty and green characteristics, seed woody and medicinal attributes. Metabolic enrichment analysis identified several key pathways involved in volatile compound biosynthesis, including sesquiterpenoid and triterpenoid formation, glycolysis, pyruvate metabolism, and fatty acid synthesis, as well as the biosynthesis of cutin, suberin, and waxes. Additional contributions to the complexity of the Hass avocado volatilome were observed from pathways such as fatty acid elongation, GPI-anchor biosynthesis, and fatty acid degradation. The peel, pulp, and seed of Hass avocado display distinct VOC profiles, suggesting tissue-specific metabolic functions. Terpenes predominate in the seed, esters and aldehydes in the pulp, and oxygenated terpenes in the peel. These findings offer insight into the biochemical basis of avocado aroma and its relevance for food quality, defense mechanisms, and potential industrial applications.