Influence of oven and microwave roasting on bioproperties, phenolic compounds, fatty acid composition, and mineral contents of nongerminated peanut and germinated peanut kernel and oils

Abstract

While antioxidant activity values of nongerminated peanut kernel extracts change between 46.58% (raw peanut) and 49.63% (oven), this values of germinated kernel extracts varied between 38.67 (oven) and 44.83 mgGAE/100 g (germinated). In addition, total phenolic contents of both nongerminated and germinated peanut kernels changed between 12.68 (oven) and 19.73 mgGAE/100 g (raw) and 23.81 (oven) and 41.62 mgGAE/100 g (germinated), respectively. p‐Hydroxybenzoic, vanillic, ferulic, quercetin, and p‐coumaric and cinnamic acids were the dominant compounds of both germinated and nongerminated peanut kernels. It was observed statistically differences in fatty acid composition of peanut oils (p < .05). The highest oleic acid contents (62.74%) were determined in nongerminated kernel oil roasted in oven. The contents of α‐tocopherol in nongerminated peanut ranged from 16.58 mg/100 g (oven roasted) to 18.64 mg/100 g (raw),while α‐tocopherol contents of germinated kernel oils change between 14.72 mg/100 g (microwave roasted) and 16.49 mg/100 g (germinated). Mineral contents of germinated peanut kernels decreased partially compared to nongerminated peanut kernels. Practical applications Nut oils are receiving growing interest due to their high concentration of bioactive lipid components, which have shown various health benefits. Germination produced high phenolic content and antioxidant activities in lupin seeds. Phenolic compounds are generally secondary metabolite produced in plants, and they might be correlated to antioxidant activity, which has been shown to retain various biological benefits; microwave energy and conventional heating are currently being used for food processing operations, including cooking, drying, tempering, baking, pasteurization, and sterilization.

Impact of roasting conditions on the quality and acceptance of the peanut paste

“…Greater oxidation was observed in oil from peanuts roasted at 200 C and in the microwave oven, with values of 0.024 and 0.017 for K 232 and 0.039 and 0.028 for K 270 , respectively. Increases in primary and secondary oxidation products have also been verified by Ziegler et al (2017), who studied the roasting of different peanut genotypes in the microwave oven and by Aljuhaimi and Ozcan (2017) that observed an increase in peroxides, from 18.63 meqÁkg −1 , in unroasted peanuts, to 74.26 meqÁkg −1 in roasted peanuts under in oven (120 C for 15 min).…”

“…Roasting alters the lipid profile by facilitating fatty acid degradation, which starts with the formation of hydroperoxides and peroxides. These changes modify the color, taste, and odor of vegetable oils, thereby negatively affecting derived products and reducing the concentration of bioactive compounds (Aljuhaimi & Ozcan, 2017; Pratt, Tallman, & Porter, 2011; Ziegler et al, 2017). Roasting develops peanut coloration, mainly through the Maillard reaction between free amines and reducing sugars (Su et al, 2011).…”

Macro‐ and microelements in pumpkin seed oils: Effect of processing, crop season, and country of origin

“…As kitchen salt, besides sodium chloride, also contains certain amounts of calcium, magnesium, and potassium, the amounts of these elements are also higher (De la Guardia & Garrigues, ). In addition, heat applied during roasting could have attributed to the increase of the dominant elements due to the thermal degradation of the cell structures as it was already reported for roasted peanuts and sesame seeds and oils (Aljuhaimi & Özcan, ; Hassan, ).…”

Optimization and validation of a simplified methodology for simultaneous extraction of fatty acids and tocopherol homologues in peanuts

“…Peanuts contain around 50 % wt. of fats, with more than 70 % of the FA being unsaturated, mainly oleic acid (42-52 %) and linoleic acid (32-37 %) (Aljuhaimi & Musa Özcan, 2018;Gavrilova et al, 2020;X. J. Liu et al, 2011;Yoshida, Hirakawa, Tomiyama, Nagamizu, & Mizushina, 2005).…”