Effect of Potash addition on groundnut oil yield and quality of kulikuli (fried groundnut cake)

Abstract

Fried groundnut cake, popularly called kulikuli, is obtained by frying the cake obtained from groundnut oil extraction. Addition of potash during defatting of groundnut is believed to increase oil yield and improve kulikuli quality, but there is little or no scientific information explaining this. This study investigated the yield, physical and chemical properties of oil extracted from groundnut with the addition of potash at 0.16, 0.32, 0.48 and 0.64%. The proximate and sensory attributes of the kulikuli produced were also determined. Groundnut yield increased from 14% to 27% with increasing addition of potash, presumably due to the emulsifying properties of potash. Potash addition significantly (p < 0.05) influenced the refractive indices, percentage impurity and colour of the oil samples. Oil extracted without potash had the lowest iodine value (85.12 mg/100 g), saponification value (202.2 mg KOH/g), acid value (6.46 mgKOH/g) and peroxide value (5.66 meq/Kg). The kulikuli had moisture in the range of 1.45 - 3.00%; carbohydrate, 20.6 - 40.4%; protein, 30.5 - 40.8%; ash, 4.45 - 5.05%; and fat, 23.5 - 30.6%. Kulikuli sample without potash was the most preferred based on taste and aroma while sample with 0.64% potash was the most preferred based on crunchiness, colour, breakability and overall acceptability. The study confirmed the hypothesis that potash addition during extraction of oil and production of kulikuli increases oil yield and some of the quality attributes of the kulikuli.

Keywords: Groundnut, potash, oil yield, kulikuli, quality attributes