Antioxidant Potentials of Turmeric (Curcuma longa) and Clove (Syzygium aromaticum) Extracts, Singly and in Synergy on Peanut Butter

Turmeric and clove are consider ed to be rich sources of phenolic compounds that can be used to replace synthetic antioxidants in fatty foods. Therefore the use of clove and turmeric extracts as natural antioxidants in peanut butter has future prospects. The main objective of this study was to preserve peanut butter with turmeric and clove ethanol extracts as natural antioxidants. The prepared peanut butter (PB) was preserved at 25 ° C with 100 ppm each of turmeric and clove extracts; mixtures of turmeric and clove in ratios 1:1, 1:3 and 3:1 respectively. Butylated hydroxyl anisole (BHA) was used as a control in another sample. Peroxide values (PV) and antioxidant effectiveness (AE) of extracts on the samples were determined on the first day and every 7 days for 28 days. Sensory analysis w as carried out on various samples of peanut butter before and at the end of storage period using a 9 - point hedonic scale. Peroxide values for all samples at the beginning of storage were 0. At the end of the storage period, untreated peanut butter showed t he highest peroxide value (23.33 me q /kg). The PB sample treated with clove extract gave the least PV (8.33me q /kg); however there was no significant difference (p≤0.05) between this value and those obtained for peanut butter preserved with turmeric extract (11.67me q /kg) Butylated hydroxyl anisole (10.00me q /kg) and sample containing turmeric and clove in ratio 1:3 (15.00me q /kg). Similarly antioxidant effectiveness was highest in peanut butter sample containing 100ppm clove extract (66.68%) and least for peanu t butter containing mixtures of turmeric and clove in ratio 1:1 (13.32%). In terms of general acceptability sample with BHA received the highest score and there were no significant differences (p≤0.05) among the peanut butter samples containing clove extra ct at 100 ppm and samples with BHA and one with mixture of turmeric and clove extracts in ratio 1:3. It can be concluded that 100ppm clove ethanol extract was the most suitable natural antioxidant and exhibited maximum score in terms of sensory attributes compared to others with added clove and turmeric extracts.