Antioxidant activity of barley as affected by extrusion cooking

• Published in: Food chemistry Vol. 131; no. 4; pp. 1406 - 1413
• Main Authors: Sharma, Paras, Gujral, Hardeep Singh, Singh, Baljeet
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.04.2012; Elsevier
• Subjects: Antioxidant activity; Barley; Biological and medical sciences; Cereal and baking product industries; Extrusion; Food industries; Fundamental and applied biological sciences. Psychology; Metal chelating activity; Reducing power; Total flavonoids content; Barley; Extrusion; Reducing power; Total flavonoids content; Antioxidant activity; Metal chelating activity; Heat treatment; Cooking; Metal; Antioxidant; Flavonoid; Polyphenol; Cereal; Power
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2011.10.009

► Extrusion lowers the total phenolic and flavonoid content of barley. ► The metal chelating and overall antioxidant activity increased upon extrusion. ► The NEB index increased upon increase in extrusion temperature. Grit from different hulled barley cultivars was subjected to extrusion cooking and the effect of extrusion moisture and temperature on the antioxidant properties was studied. A significant decrease in the total phenolic content (TPC) and total flavonoid content (TFC) was observed upon extrusion and a further decrease of 8–29% in TPC and 13–27% in TFC was observed when both the feed moisture and extrusion temperature were increased. The antioxidant activity (AOA) increased significantly upon extrusion and this increase was the highest (36–69%) at 150°C and 20% feed moisture. The increase in feed moisture and temperature significantly increased the metal chelating activity. The reducing power decreased significantly upon extrusion as compared to their corresponding control samples. Extrusion lead to a greater increase in non-enzymatic browning (NEB) index however, increasing the moisture content of feed decreased the NEB index by 3–29% (at 180°C) and 1–17% (150°C), while increasing the temperature increased the NEB significantly.