Flaxseeds nutritional value and the effect of its incorporation in some loaf properties with and without addition of transglutaminase

الملخص EN

The aim of this study was to determine the major nutrients in local flaxseeds, the amino acids content, the fatty acids content of extracted oil, and to investigate the effects of 5% seeds flour replacement and addition of microbial transglutaminase on some properties of dough and loaf bread.

Results showed that these seeds contained 4.93, 22.28, 36.03, 31.03, 18.03, 3.63and 1.08% (ww) of moisture, protein, fat, total carbohydrates, crude fiber, ash and reducing sugars respectively with 1.83mg 100 gm sample of Vitamin C.

Results of amino acids analysis indicated aspartic acid, glutamic acid, arginine as non –essential and tryptophan and phenylalanine as essential amino acids to be the main components of seeds protein, they represent 4.522, 3.486, 1.88 and 2.414, 0.695 gm /100gm sample respectively.

The analysis of fatty acids content, showed twenty nine fatty acids.

Unsaturated fatty acids spatially α-linolenic and oleic acids, were predominant, they comprise 24.94 and 22.79 g/100g of the total FA respectively, while palmitic acid was the major saturated fatty acid found in seeds and comprised 13.60% of total lipid.

The minerals, calcium, manganese, potassium and iron, were present in high concentrations.

Results indicated that the replacement of wheat flour by 5% ground flaxseed decreased wet gluten, tolerance index, loaf specific volume and increased dough water orption, stability and fermentation gassing power.

Sensory evaluation showed that the incorporation of these seeds flour had a slightly unfavorable effect on bread sensory properties but ensured satisfactory consumer acceptability.

Addition 2 units g protein of microbial transglutaminase caused increasing in wet gluten, gassing power of fermented dough, loaf specific volume and all sensory attributes.