Tocopherols: their role in stabilizing anhydrous butter-fat[Ghee] and butter cookies

Two different concentrations of mixed Tocopherols known commercially as Covi-OxT50 [Covi 50] and Covi-OxT70 [Covi 70] together with a single concentration of a synthetic antioxidant known as Tenox 25 [T25] were added to butter and anhydrous butter fat [ABF] Ghee. Butter cookies made from the aforementioned butter were prepared and stored at tropical room temperature conditions [37-45°C and 95% RH] for 4 months. Chemical and sensory tests were performed for quality testing. The oxidative stability of ABF was performed by determining the conjugated dienes [CD], acid value [AV], free fatty acids [FFA] and peroxide value [PV] at regular intervals [2 weeks] under accelerated storage conditions [63°C for 6 weeks]. Results of the oxidative rancidity Indicated that the addition of Covi 70 and T25 to the ABF significantly [P<0.05] retarded the oxidative rancidity as measured by the aforementioned parameters. No significant effects were detected in most of the tests between Covi 70 and 125 which emphasize the outstanding effect of Covi 70 in retarding the onset of rancidity and stabilizing the ABF under the experimental conditions. Results of the chemical analysis indicated the presence of a significant [P<0.05] drop in both the moisture content and the pH values and a significant rise [P<0.05] in the TBA values of the stored cookies as a function of time. Both Covi 50 and Covi 70 exhibited a significant [P<0.05] effect in maintaining the aforementioned parameters as compared to the control and the synthetic antioxidant. The sensory evaluation results showed that higher scores for the taste, odour and overall acceptance were given to the Covi 70- containing cookies as compared to the control and the other added antioxidants

Effect of added tocopherols on the stability of palm olein and biscuits contaning palm olein stored at tropical conditions

The oxidative stability of palm olein oil, with an added synthetic antioxidant, namely; Tenox 25 [T25] and two concentrates of tocopherol mixtures, namely, Covi Ox-T50 [Covi 50] and Covi Ox-T70 [Covi 70] was evaluated for 4 months storage under tropical conditions. The oxidative stability of palm olein oil stored under the aforementioned conditions was monitored by determining the conjugated dienes [CD], acid value [AV], free fatty acid [FFA], peroxide value [PV], p-anisidine value [PA], iodine value [IV] and the total oxidation value [TOTOX]. The antioxidant index [AI] was also calculated. The quality of biscuits containing palm olein oil was also evaluated under the aforementioned storage conditions. Data were analysed by the general linear analysis. Results of the oxidation measurements showed that the activity of the individual antioxidants used in the present study varied with the same type of oil, but in most of the tests, the tocopherols were as equally effective as the strong synthetic T25 and/or more superior than it in many aspects. The AI for the different antioxidants had values higher than unity and were similarly effective as T25 indicating their antioxidative powers in inhibiting the onset of rancidity in the stored oil. Results of the quality tests of the stored biscuits indicated that the low concentrate tocopherol Covi 50 significantly [P<0.05] prevented moisture loss and rancidity development as measured by the thiobarbituric acid number [TBA] as compared to the other antioxidants. Both added tocopherols and T25 were equally effective in preventing the pH rise of the stored biscuits as compared to the control. The sensory evaluation showed that higher scores were given by the panelists for all antioxidant treated samples without differentiation