Wheat Milling Quality And Its Relationship With The Quality Of Steamed Bread

Milling quality was considered an important character in wheat processing quality, directlyaffecting the enterprise’s benefit and foods processing quality such as bread, steamed bread. Theimprovement of milling quality including three important parameters, such as flour yield, flour ashcontent and whiteness, has been regarded as an important content of the wheat quality improvement.The present research is to study wheat varieties (lines) from different winter wheat regions, foridentifying the variation and distribution characteristics of wheat milling quality and steamed breadquality in different years, and analyzing relationships between wheat milling quality and steamed breadquality. The results were described as following:1. Variation and distribution characteristics of wheat milling quality in wheat varieties (lines)(1) The smaller coefficients of variation for flour yield, flour ash and whiteness were at5.53%,7.41%and4.57%, respectively. Furthermore, their coefficients of variation hardly suffered frominfluence of environmental conditions, were mainly attributed to genetic control of wheat varieties.(2) The averages of wheat flour yield exceeded60.00%in both2012and2013years, especially,the highest flour yield was at80.00%in2013year. The standard deviations of flour ash content areconsistent of0.05in both2012and2013years. Flour whiteness values exceeding80.00were found sixvarieties (lines) in2013years, which includes09-A6(80.10), Xumai9166(80.27), Neixiang188(80.83),Lian5105(80.90), BH50890-1-1(81.20), Xumai31(81.30). However, its values were all less than80.00in2012year.(3) The variations of average among flour yield, flour ash and whiteness are wider ranges in bothtwo years. Flour yields above70.00%were found on1.83%wheat varieties (lines), includingLuoyou9905(71.69%), nannong30I-87(70.36%) and nongda189(73.64%). Flour ash between0.40%and 0.50%, and above0.70%were discovered in one wheat varieties (lines)(08luo303,0.48%) and2wheatvarieties (lines)(CL0407,0.74%and OTTO,0.74%), respectively. And, flour whiteness above80wereonly2varieties (lines), which were wanmai19(80.18) from anhui province and chuanyu55871(80.17)from sichuan province.2. Steamed bread processing quality(1) After two consecutive years of steamed bread processing quality analysis, the results showedthat the coefficients of variation for four sensory quality parameters (specific volume, appearance,stickiness, Taste&flavor) and four parameters texture (hardness, adhesion, adhesiveness and chewiness)were relatively larger. Moreover, the ones for appearance, color, cohesion and elasticity are relativelystable among different years.(2) Many materials with better sensory quality were selected, i. e. Neixiang03-36, T21-6, Keyu818,Zhongyou9507and Qinnan mai. Meanwhile, several materials with better hardness and chewiness werealso selected, i.e. Chuannong05152,09P131, Zhongyou9507, Bayou1and Xuaiyou2004.(3) In the sensory quality and texture of each parameter between two years, there existed arelatively concentrated distribution, such as, bread score>80.00(53.57%), specific volume17.00-19.00(54.76%), adhesion0.10mJ-1.00mJ (90.48%), cohesion0.75-0.80(92.86%).(4) Correlation analysis showed strong positive correlations between total score and other7parameters from sensory quality, being from0.407**to0.764**. Additionally, strong positivecorrelations above0.950**were found among hardness, adhesiveness and chewiness from texture. Itwas also noteworthy that only two sensory quality parameters (specific volume and structure) andtexture existed close correlations.3. Correlation between wheat milling quality and steamed bread processing quality(1) Wheat flour yield had negative correlation with all sensory quality parameters, further havingsignificant negative correlations with both color and total score, which were-0.270*and-0.245*; respectively. There was a significant positive correlation existed in flour ash and specific volume(r=0.256*). And, it were found that flour whiteness was significant positive correlations with threesensory quality parameters: color, stickiness and total score.(2) Wheat flour yield had positive correlations with three texture parameters: hardness,adhesiveness and chewiness (r=0.222*-0.257*). On the contrary, flour whiteness was negativecorrelation among ones (r=-0.269*--0.217*). Additionally, it was showed that flour ash was no closedwith all texture parameters.