Development and optimization of peanut chocolate spread for Ghanaian consumers

Abstract

Epidemiological data have linked lower risk of certain diseases including cardiovascular disease to regular consumption of peanuts. To promote enhanced benefit from the nutritional and health benefits of peanuts, there is the need to broaden the scope of consumer choice through diversification of the uses of peanuts. This study optimized the formulation for consumer acceptance of the sensory attributes of a prototype Peanut-chocolate Spread for commercial adoption. Peanuts were heat blanched at 140ᵒC for 30 minutes, sorted for moldy and shriveled nuts, deskinned followed by removing discolored kernels. Sorted peanuts were roasted for 100 minutes at 140ᵒC to medium roast (L=50) in 2 kg batches. A constrained simplex mixture design using the following proportions of peanuts, natural cocoa powder and sugar: 0.30-0.80; 0.05-0.55 and 0.15-0.65 respectively. Nine formulations were obtained. These were milled and stabilized with 1% PS 105 K-A (Danisco, USA) stabilizer in a plate mill and then conditioned for 24 hours at 10ᵒC. A total of 60 consumers rated the sweetness, peanut flavor, chocolate flavor, smoothness, spreadability and overall liking of the coded prototypes in two sessions using a 9-point hedonic scale. The sensory evaluation was conducted using central location testing in the Accra metropolis. The average rating of the attributes ranged from dislike slightly (4.0) to like very much (8.0) as follows: Sweetness (4.45-7.30); Peanut Flavor (5.18- 7.37); Chocolate Flavor (5.28-6.97); Smoothness (4.90-7.60); Spreadability (3.60-7.63) and Overall Liking (4.97-7.57). The contour overlay of the attributes indicated that a Peanut-chocolate Spread acceptable to consumers can be produced from any of the combinations of 0.65-0.79 peanuts, 0.15- 0.29 sugar and 0.05-0.13 cocoa powder. FRI has engaged an industrial partner to whom this technology will be transferred. The results of this research should significantly help to promote utilization of peanuts in Ghana