Comparison of Fatty Acid Profiles in Jack Bean By-Product Oil Compared with Soybean and Commercial Vegetable Oils

Jack bean (Canavalia ensiformis) is an emerging alternative plant-based protein source, but lipid-rich by-products from its extraction remain underexplored. This study aimed to characterize the fatty acid profile of oil from defatted jack bean flour and compared it with black soybean (Glycine max), refined palm oil, and refined soybean oil. Jack bean and soybean seeds were blanched, soaked, dried, milled, and extracted with n-hexane (1:5, w/v). Lipid extraction and fatty acid analyses were performed in duplicate, and fatty acid methyl esters were analyzed by gas chromatography according to ISO 12966-4:2017. Jack bean flour yielded 2.23% oil, significantly lower than black soybean flour (18.76%; p < 0.05). Nineteen fatty acids were identified in jack bean oil, dominated by oleic acid (48.19%), γ-linolenic acid (16.00%), palmitic acid (15.96%), and linoleic acid (6.90%). Jack bean oil contained significantly more γ-linolenic acid and less linoleic acid than the comparison oils (p < 0.05), indicating a distinct fatty acid profile. An EPA-like peak (4.27%) was tentatively detected but requires confirmation. The oil showed favorable MUFA/SFA (2.65) and ω-6/ω-3 (2.96) ratios, highlighting its potential for valorizing protein-extraction by-products within a circular economy framework.