14B-41

J. CHUN, J. Lee, and R. R. Eitenmiller. Department of Food Science and Technology, University of Georgia, Athens, GA 30602

Consumption of nuts and seeds is related to low incidence of coronary heart disease. This protective effect may be related to favorable fatty acid composition and other intrinsic components including folate, vitamin B-6, vitamin E, selenium, sterols and other phytochemicals. Especially, peanuts and peanut products are good sources of vitamin E. However, little is known about the stability of vitamin E in peanuts during processing.

To determine the effect of roasting and peanut butter manufacture on vitamin E stability of peanuts and to provide more complete data on the vitamin E content in raw, roasted peanuts, peanut butter and peanut oils.

Peanut oils were purchased locally. Raw and dry roasted peanuts and peanut butter were obtained from Tara Foods, Albany, GA. Five trials tracing processing from raw to dry roasted to peanut butter were conducted. Direct solvent extraction was used for the extraction of tocopherol homologs. HPLC was completed on Lichrosorb Si60 with a mobile phase of hexane:isopropanol (99.2:0.8) and fluorescence detection (Ex_l=290, Em_l=330).

a-Tocopherol equivalents (a-TE) were 11.7, 8.7, and 11.4 for raw peanut, dry roasted peanut, and peanut butter, respectively. The a-TE values for dry roasted peanut decreased by 25.6% compared to raw peanuts. The a-TE values for peanut butter samples ranged from 10.4 to 12.5 and were higher than the corresponding roasted peanuts. Addition of peanut oil and rapeseed oil based stabilizer to the roasted nuts during processing accounts for the increase in a-TE values. a-TE levels in commercial peanut oil ranged from 12.4 to 28.0.

The study expands the available data on vitamin E for peanuts and peanut products. Dry roasting decreases vitamin E in peanuts; however, peanut butter contains levels equivalent to that of raw peanuts due to the additive effect of the ingredients.