Flour Color and Dough Sheet Browning of Wheat Flour Coming from Different Flour Milling Systems

Key words: 
• Wheat flour /
• dough sheet /
• color /
• ash /
• bran speck /
• brown stain

Abstract: In order to understand the relationship of wheat flour milling systems with wheat flour color,dough sheet color and brown stain of the flour from different flour milling systems and well improve wheat flour quality,the wheat flour samples collected from 20 streams of flour milling systems were determined to observe their L^*,a^*,b^*values,ash content,protein content,bran speck area,black dot area,dough sheet color and browning.The results showed that flour milling system had a great influence on wheat flour color except raw grain and its cleaning effect. The b^*values,ash content,protein content,bran speck area and black dot area of wheat flour were higher in the latter than the former streams,and tended to decline gradually in the XF flour,the latter break streams of B flour,T flour,the former break streams of B flour,the former streams of M flour,D flour,S flour,the former reduction streams of M flour; L^*,a^*values were just the opposite. Dough sheet color of different flour systems gradually became darker over time,had the highest change at 8 h and 24 h and turned brown obviously. Dough sheet of the former streams of M flour was higher in L^*value than those from other streams of flour,and it was whiter and was browning slowly,followed by B flour,T flour and D flour. The former reduction streams of M flour was the best and belonged to fine powder in the four milling systems. XF flour was the worst and belonged to poor powder since its dough sheet color was dark and yellow. Therefore,the former break streams of B flour and the former reduction streams of M flour were recommended as high quality wheat flour with good color.