Abstract
Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts’ antioxidative properties when added to soybean oil.
Highlights
Peanut skins are waste from the blanching process of peanuts, which are recognized for their bioactive compounds’ antioxidative properties
Proanthocyanidins isolated from the water-soluble fraction of peanut skins exhibited antioxidant activity [4]
While the blanching process influences both the total phenolic and isolated procyanidin contents [7], the total phenolics and procyanidins present in skins that were peeled by hand or by roasting presented concentrations comparable to those found in grape seeds
Summary
Peanut skins are waste from the blanching process of peanuts, which are recognized for their bioactive compounds’ antioxidative properties. These skins are a potential source for natural antioxidants, they have only been used for animal feed. Proanthocyanidins [1] and flavonoids [2] have been isolated from the water-soluble fraction of peanut skins. Radical scavenging activity in relation to the content of total phenolic compounds and trans-resveratrol in fractions from ethanolic extracts of peanut skins was reported [3]. Proanthocyanidins isolated from the water-soluble fraction of peanut skins exhibited antioxidant activity [4]. The total antioxidant activity and free radical scavenging capacities of peanut skin extracts were all higher than those of Trolox or Vitamin C at equivalent concentrations
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
