Abstract
Abstract This study investigates the chemical composition of black chokeberry (Aronia melanocarpa (Michx.) Elliott) fruit extracts collected during the summer and autumn of 2024 in the Trans-Ili (Zailiysky) Alatau region. Gas chromatography-mass spectrometry (GC-MS) was employed to determine seasonal variations in metabolite profiles and to evaluate the effect of fruit ripening on biochemical composition. Summer extracts were dominated by volatile organic compounds, particularly furan and lactone derivatives such as dihydro-3-methylene-5-methyl-2-furanone and 5-hydroxymethylfurfural. Their abundance reflects intensive carbohydrate dehydration and thermo-enzymatic transformations associated with active metabolic processes during fruit growth. In contrast, autumn extracts exhibited a shift toward more stable metabolites, including polyols (sorbitol, mannitol, isosorbide), fatty acids (oleic, linoleic, palmitic), and phytosterols (γ-sitosterol, campesterol). This compositional transition indicates the completion of biochemical maturation, accompanied by enhanced antioxidant accumulation and stabilization of the lipid-polyol fraction. Seasonal comparison revealed that summer extracts possess higher aromatic and volatile compound content, contributing to increased reactivity and flavor intensity, whereas autumn extracts are characterized by a higher proportion of non-volatile metabolites, resulting in improved chemical stability and antioxidant capacity. These findings highlight the critical role of harvest timing in optimizing extraction strategies for Aronia melanocarpa fruits intended for food, pharmaceutical, and cosmetic applications.