Variability in fatty acid composition, oxidative status, and vitamin E content of commercial roasted Peanuts

Abstract

Abstract

This study evaluated the oil quality of roasted peanut samples collected from different Turkish producers (M–T7) by analyzing oil yield, acidity, peroxide index, vitamin E content, oleic/linoleic acid ratio, fatty acid composition, and multivariate relationships using principal component analysis (PCA). Oil yields varied from 47.81% to 57.64%, reflecting differences in raw materials and processing efficiency. Acidity values (0.13-0.61 mg KOH g⁻¹) and peroxide indices (0.15-7.19 meq O₂ kg⁻¹) indicated generally good oil quality, although some samples showed early oxidative or hydrolytic degradation. Vitamin E content ranged widely (0-166.50 mg 100 g⁻¹ oil), highlighting variability in antioxidant capacity and its inverse relationship with oxidation. Oleic/linoleic acid ratios ranged from 1.78 to 20.99, allowing discrimination between conventional and high-oleic profiles, with higher ratios associated with improved oxidative stability. Fatty acid analysis confirmed oleic and linoleic acids as the dominant components, with marked inter-sample variability. PCA revealed that sample dispersion was mainly driven by fatty acid composition, oxidation indices, and antioxidant content, reflecting heterogeneous genetic origins and processing conditions. These findings demonstrate substantial quality variability among commercial roasted peanut products and underline the importance of systematic quality assessment for industrial applications.