Using Egyptian Caper Seeds Oil Capparis spinosa L as a Natural Antioxidant to Improving Oxidative Stability of Frying Oils During Deep Fat
Abestract: The addition of natural antioxidants in food plays an important role to avoid toxic effects of synthetic antioxidants. This work was aimed to evaluate the effect of natural antioxidants addition in the protection of sunflower and soybean oils as frying oils during the deep frying of potato fingers at 180degC for 180 min, since caper seed oil (CSO) as a rich source of natural antioxidants. The CSO was added to sunflower and soybean oils separately at ratio as follows: 200, 400 and 600 ppm. Besides, 200 ppm of tertiary butylhydro quinone (TBHQ) served as a control sample. From the obtained results it could be concluded that the CSO contain higher phenolic compounds content (858.54 mg/100g) total tocopherols (758.12 mg/100 gm as vitamin E) total carotenoids (675.8 mg/100 g) and the DPPH activity was recorded (152.40 The induction period (IP) in hrs was taken as an index for the oxidative stability of the oil samples. However, the addition of CSO to oil samples at different mentioned levels led to increase its stability against oxidation. The higher IP of sunflower and soybean oil samples was found at addition ratio of the CSO 600 ppm was (9.89 and 8.11 hrs, respectively) compared with the TBHQ (6.67 hrs, as control sample) During frying process of potato finger, the results showed that the addition of CSO at levels 400 and 600 ppm to sunflower and soybean oils reduced the refractive index, free fatty acids, peroxide, TBA values and polymer content as compared to oil samples treated with TBHQ under the same conditions. Although the soybean and sunflower oils had the highest amounts of polyunsaturated fatty acids, but the CSO was exhibited superior ability in protecting the oil from oxidation during frying process. Finally, it can be recommended that the caper seed oil (CSO) suggests as a good natural antioxidant alternative to TBHQ as antioxidant in frying oils.