Abstract
The effect of tehina processing and storage during six months at 25 degrees C and 35 degrees C on total phenolics, antioxidant activity, anthocyanins, and fatty acid analysis was evaluated. Tehina processing, storage period and temperature significantly (p <= 0.05) decreased total phenolics, antioxidant activity and anthocyanins contents. The results showed that raw sesame seeds had the highest total phenolics (99.98 mg GAE/100 g) and lower levels were found in dehulled unroasted sesame seeds, tehina at zero time and roasted sesame seeds (62.53, 60.61 and 47.03 mg GAE/100 g, respectively). In addition, tehina during storage showed a significant decrease in total phenolics (60.61 to 42.45 mg GAE/100 g). Raw sesame seeds had the highest antioxidant activity (0.51 mg/mL), while the tehina, dehulled unroasted and roasted sesame had antioxidant activity values of 1.21, 1.35 and 1.79 mg/mL, respectively. Also, antioxidant activity of tehina at zero time was highest (1.21 mg/mL) and lowest was in tehina stored for six months (1.70 mg/mL). Sesame seeds and tehina had low levels of anthocyanins (1.26 and 0.50 mg cya-3-glu/100 g). Fatty acid analysis showed that sesame seeds (raw, dehulled unroasted and roasted) and tehina samples contain high percent of unsaturated fatty acid oleic (C18:1) and linoleic (C18:2).