Effect of Adding Walnut Powder on Physical and Chemical Properties of Wheat Flour and Preventing Hyperlipidemia in Mice

Abstract

Walnuts ( <i> Juglans regia </i> L . ) are naturally rich source of many important nutrients which could be helpful in different food processing. Walnut mainly containing polyunsaturated fatty acids (PUFA), especially alpha linoleic acid (18:3n-3; 9 g) and linoleic acid (18:3n-; 38 g). Walnuts powder was fortified with commercial high gluten wheat flour (WF) into 4 composites flour from 10% to 40%. Walnut flour improves the nutritional value due to high protein and fat content, but affect s the technological properties. Parameters such as functional, pasting and rheological properties demonstrated the influence of walnut reincorporation into gluten network. The interaction of walnut flour with wheat flour is a key factor which effect s on the dough quality, causing thinning and weakening the gluten structure. Flour with 30% to 40% walnut substitution w as more nutritious especially in relation to protein and monounsaturated fatty acid (MUFA), but responsible for more changes in technological characteristics of dough. Present study w as also directed to examine the effect of moderate walnut consumption on lipids profile, enzymatic anti-oxidant (superoxide dismutase SOD and glutathione peroxidase GSH-Px) and lipid peroxidation ( Melondialdehyde MDA) in rats fed with high - fat food. The Sprague Dawley rats were housed for five weeks and assembled into normal, high fat, high fat (HF) + 10% walnut, HF + 20% walnut, HF + 30% walnut and HF + 40% walnut. The lipid profile significantly improved especially by lowering the low - density lipoprotein cholesterol (LDL-c) and high - density lipoprotein cholesterol (HDL-c) level increased in the group of HF + 40% walnut. The total anti-oxidant, SOD and GSH-Px activity were increased by supplementation of walnut and significantly higher in HF + 40% compared to the normal group. The Melondialdehyde (MDA) or lipid peroxidation status w as increased in HF + 20% walnut to HF + 30% walnut as compared to normal and HF - fed diet but reduced by HF + 40% walnut. These results suggest that walnut intake could be effective to protect from oxidative stress by lowering the lipid peroxidation by improving antioxidant defense system in rats fed high - fat diet.