|BOLTON, GREGORY - NC STATE UNIVERSITY
Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/22/2002
Publication Date: 2/27/2002
Citation: Bolton, G.E., Sanders, T.H. 2002. Effect of high oleic acid peanut roasting oil on the stability of regular and partially defatted peanuts. Journal of the American Oil Chemists' Society. Vol. 79, pp 129-132.
Interpretive Summary: High flavor oil-roasted peanuts already meet the need of consumers interested in healthy, good tasting snack food. Nutritional information indicates that products with oil containing high concentration of monounsaturated fatty acids decrease cardiovascular risk factors by lowering total and LDL cholesterol. In this study we used high oleic acid peanut oil to roast regular and partially defatted peanuts to determine if we could improve shelf-life and increase the concentration of oleic acid. Oil uptake by regular peanuts was about 3%, but oil content in pressed peanuts increased from 31 to 40%. Shelf-life increased in both types of peanuts with use of the high oleic oil. The data indicate that the concentration of monounsaturated fatty acid can be increased by oil roasting with high oleic oil and further demonstrates that addition of other flavor compounds may be included in frying oil to change flavor profiles.
Technical Abstract: Regular and partially defatted (pressed) peanuts were roasted in conventional and high oleic peanut oil to determine changes in shelf-life. The amount of oil uptake, oil exchange, and oil coating was evaluated. Pressed peanuts increased from 31 to 40% oil during roasting in both oils, while regular peanuts increased from 55 to 57% oil. Oleic acid to linoleic acid ratio (O/L) increased from 1.7 to 2.0 in regular peanuts after roasting in high oleic oil, but remained unchanged after roasting in conventional oil. Pressed peanuts increased from 1.7 to 3.5 after roasting in high oleic oil and decreased slightly after conventional oil roasting. Pressed peanuts were found to increase in oxidative stability after roasting in high oleic oil compared to regular peanuts roasted in either oil. Post-roast treaments to increase uptake of high oleic oil into peanuts did not significantly improve oxidative stability.