[Comparison of physical, chemical, rheological and baking properties of some local and imported wheat varieties]

ABSTRACT

This study was conducted to compare Physical, Chemical, Rheological, and Baking characteristics of some local [Pawni and Samra] and imported [Australian and U.S.] wheat varieties. All grains were cleaned and subjected to Physical tests and then ground and subjected to Chemical, Rheological, and Baking tests. Results of physical characteristics showed high humidity in Australian and U.S. wheat grains, and lower in local wheat grains of both Samra and Pawni varieties. Thousand-grain weight of local wheat Samra and Pawni recorded high values, while American wheat showed the lowest values. Imported wheat showed higher specific weight and had the highest average value of Particles Size Index [PSI%] as compared to local wheat varieties. Results of chemical characteristics of local wheat flour Samra and Pawni showed higher percentage of lipid, protein, ash, damaged starch granules, total Pentosans and water soluble Pentosans contents as compared to imported varieties, while the proportion of crop flour and wet gluten were higher in imported wheat compared with local wheat flour. All wheat varieties, particularly Samra and Australia showed lower activities of amylases enzymes as compared to best value. Farinograph results indicated that water absorption of local wheat flour [Pawni and Samra] was higher than imported wheat flour especially U.S. wheat flour. Australian wheat flour showed high dough development and stability time compared with local wheat flour; however, imported American wheat flour recorded lower value. There was no significant difference [P?0.05] between the two types of local wheat flour on the average values of development and stability time. Results of baking characteristics and sensory evaluation indicated that imported Australian wheat flour showed the highest specific loaf volume, followed by American; however, local wheat flour had the lowest volume. The results of sensory evaluation agreed with the results of baking characteristics regarding to baking quality factors