UTILIZATION OF CAROTENOID PIGMENTS EXTRACTED FROM TOMATO PEEL AS NATURAL ANTIOXIDANTS AND COLORANTS IN SUNFLOWER OIL AND SPAGHETTI

Abstract

Extraction and Determination of carotenoids pigment from tomato peel was optimized for identification of the major constituent of the extract by HPLC to be used as alternative natural colorants in some processed foods, i.e. spaghetti. Also the effect of using carotenoids from tomato peel as natural antioxidant on sunflower oil was also undertaken. Tomato peel contained 720 mg carotenoids /100g. The carotenoids (lyco-red) extracted from tomato peel were separated based on their functional groups into thirteen fractions and identified nine compounds from them by HPLC. lycopene was the major carotenoid represented with 86.12 % of total carotenoids from tomatoes peel followed by 3.15% phytoene, 2.31% phytofluene, 2.11% β-carotene, 1.71% cis-lycopene, 1.51% lutein, 0.61% cis-ζ-carotene, 0.56% ζ-carotene, and 0.52% γ-carotene respectively. Antioxidant activity of carotenoids from tomato peel were evaluated by measuring Rancimat test on sunflower oil by adding 50 to 200 ppm carotenoids from tomato peel and radical scavenging activity RSA by DPPH. The sunflower oil containing 50 to 200 ppm carotenoids from tomato peel showed a higher induction period compared to the sunflower oil containing 200 ppm (BHT) as a synthetic antioxidants. Optimum cooking time, cooking weight and swelling index were not differed within each level of oil carotenoids tomato peel powder compared with control. On the other hand, spaghetti cooking losses were decreased by increasing the level of carotenoids in spaghetti compared with control (without added carotenoids). Supplementing spaghetti with carotenoid (lyco-red) from tomato peel increased the Radical Scavenging activity (RSA) in the spaghetti by increasing the percentage of added carotenoid (lyco-red) from tomato peel. Sensory evaluation of spaghetti prepared from carotenoid pigments from tomato peel revealed the highest score of color, taste, texture and overall acceptability compared with control and other tested samples.