Comparative Analysis of Raw and Roasted Peanut Skins: General Composition, Fatty Acids, and Minerals

Tulin Eker; Pinar Kadiroglu

doi:10.57252/jrpfoods.2025.5

Authors

Tulin Eker Dr.
Pinar Kadiroglu

DOI:

https://doi.org/10.57252/jrpfoods.2025.5

Keywords:

Agro-industrial by-product, Valorisation, Peanut skin, Fatty acid composition, Mineral content

Abstract

Peanut (Arachis hypogaea L.) is widely cultivated in Türkiye, particularly in the Osmaniye region, and its processing generates a substantial amount of peanut skin as a by-product. Although commonly discarded, peanut skins contain valuable nutritional components. This study aimed to determine the general composition, fatty acid profile, and mineral content of peanut skins as well as to evaluate the effect of roasting on these parameters. The moisture, ash, fat, and protein contents of roasted and raw peanut skins were determined as 11.42%–9.86%, 3.62%–3.79%, 19.64%–15.91%, and 16.89%–14.94%, respectively. The results showed that raw peanut skin had higher moisture, fat and protein levels compared to the roasted samples. Oleic and linoleic acids were identified as the predominant fatty acids in peanut skins, accounting for over 70% of the total fatty acid composition, with slightly lower levels in the roasted samples. Mineral analysis revealed that potassium, calcium, magnesium, and phosphorus were the major elements in peanut skins. While the levels of potassium and magnesium increased after roasting, other minerals such as calcium, phosphorus, iron, manganese, copper, and zinc showed a decreasing trend. These findings highlight the underutilized nutritional potential of peanut skins and offer valuable insights into the compositional differences between raw and roasted forms.

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