Chemical composition of some wild peanut species (Arachis L.) seeds

Abstract

Oil, protein, ash and carbohydrates contents, iodine value, fatty acid composition and sterol composition were studied in seeds of Arachis trinitensis, A. chiquitana, A. kempff-mercadoi, A. diogoi, , A. benensis, A. appresipila, A. valida, A. kretschmeri, A. kuhlmannii, A. williamsii, A. sylvestri, A. matiensis, A. pintoi, A. hoehnei, A. villosa and A. stenosperma. Oil content was greatest in A. stenosperma (mean value = 51.8%). The protein level was higher in A. sylvestris (30.1%) and A. villosa (29.5%). Mean value of oleic acid varied between 30.6% (A. matiensis) and 46.8% (A. villosa), and linoleic acid oscillated between 34.1% (A. villosa) and 47.4% (A. appresipila). The better oleic-to-linoleic (O/L) ratio was exhibited by A. villosa (1.38). Some species showed higher concentration of behenic acid. The greatest level of this fatty acid was found in A. matiensis (6.2%). Iodine value was lower in A. valida (99.2). The sterol composition in the different peanut species showed higher concentration of sitosterol (mean value oscillated between 55.7 and 60.2%) followed by campesterol (12.4-16.5%), stigmasterol (9.7-13.3%), and avenasterol (9.7-13.4%). The chemical quality and stability of oils (iodine value and O/L ratio) from wild peanut studied in this work are not better than those of cultivated peanuts.