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A nondefatted peanut beverage (NDPB) and a partially defatted peanut beverage (PDPB) were processed under high temperature at 110°C or 121°C for 3 set with homogenization pressures equivalent to 2000 or 3000 psi. Beverages were evaluated for suspension stability, viscosity, and color (L) values. Sensory ratings for color, viscosity and chalkiness were also determined. All processing conditions produced very stable emulsions. PDPB were rated significantly darker, more viscous (P 2 0.01) and more chalky (P 5 0.05) than NDPB. The NDPB samples homogenized at 3000 psi were rated lighter, and were characterized by greater particle size reduction than samples homogenized at 2000 psi. Sensory and objective measures were observed to be highly correlated.

Differences in sensory qualities of a peanut beverage processed at 85", loo", and 121°C for 5, 15 and 25 min were determined using analysis of variance (ANOVA) techniques. Temperature significantly affected cooked flavor, raw and cooked odors, viscosity and color. Time had significant effects only on cooked flavor and color. Factor analysis was used to determine relationships among sensory qualities and gas chromatographic peaks of the headspace volatiles. Seven factors accounted for 91% of data variance. Processing at 100°C yielded a peanut beverage with sensory quality better than the product processed at either 121°C or 85°C.

Nutritional, microbiological and sensory qualities of peanut beverages processed at 85"C, 100°C and 121°C for 15 min and 121°C for 3 set were determined. Heating improved the digestibility of peanut beverages, particularly those processed at 121°C for 3 set and 85°C for 15 min. Methionine was particularly sensitive to the treatment at 121°C. The limiting amino acids were threonine, cystine, valine, lysine and tyrosine. No microbial growth was observed in products processed at 100°C and 121°C followed by storage at 4°C and 30°C for 20 days. Beverage processed at 85°C and stored at 30°C for 3 days contained an aerobic microbial population of 2.4 x lo4 CFU/mL. The beany flavor was least pronounced in beverages processed at 100°C for 15 min and strongest at 121°C for 3 sec.

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