|
Production of wheat quality status to master the Guanzhong area Daejeon improve bread quality analysis and evaluation of technology, produced in 2008 in Shaanxi Guanzhong Daejeon 92 wheat samples for the material in the systematic analysis of wheat grain physical quality, milling quality, protein quality starch quality, dough rheological properties and bread on the basis of food quality traits identified key indicators that affect the quality of wheat, and Shaanxi Guanzhong quality wheat production area, and bread sensory evaluation of the quality indicators Texture Analyzer, color colorimeter The test indicators combined, a clear key indicators of the evaluation of the quality of the bread, and bread quality evaluation system is built. The main results are as follows: (1) the Guanzhong area Daejeon production wheat bulk density, grain hardness, protein content were higher, but lower sedimentation value, protein quality is poor, and the general performance of the dough rheological properties. Field production of 15% of the wheat samples reached quality wheat - strong gluten wheat requirements of the national standards, 9% to a high-quality wheat - weak gluten wheat requirements of the national standards, and the remaining 76% in gluten wheat. (2) in Guanzhong three regions, Weinan region wheat flour yield higher chroma better flour, grain protein content is lower, but better quality gluten the dough farinograms and stretching parameter performance fine. Wheat grain weight of Xianyang, bulk density and grain chroma more balanced, relatively low flour yield, higher flour ash content, protein content, sedimentation value, wet gluten content, gluten index the excellent farinograms, dough extending small, flexible and strong. In Baoji low bulk density and grain hardness of wheat, grain protein content, gluten poor quality, general performance the silty parameters and tensile parameters. (3) evaluation of 29 indicators of wheat quality traits by factor analysis of compressible seven public factor, the protein quality factor, the processing quality factor, starch pasting properties factor, gluten quantity factor, grain physical quality factor, starch hot paste stability the factor, starch rebound factor, the cumulative contribution rate of more than 82.14%. Flour L *, ash content, grain protein content, water absorption, the degree of softening, the evaluation value, maximum resistance, tensile energy, the peak viscosity (B), starting thermostat gelatinization resistance (C), starting cooling paste Turning obstacles (D), the cool end of the the gelatinization resistance (E) Cluster analysis and damage values ??(BD) 13 indicators, 92 the Daejeon production of wheat samples can be divided into three categories (region), Sanyuan County, Jingyang County Wugong County in the northern region wheat field production of a class of the area drier the better wheat flour farinograms, stretching parameters and starch pasting properties superior; of Weinan District Linwei Pucheng County field production samples of wheat a class of wheat flour in the area farinograms better tensile parameters starch pasting properties in general; Pucheng County, along the provincial highway through Fuping County, Sanyuan County, Jingyang, Wugong County Fufeng County, Qishan County field production of wheat and Fengxiang county's eight counties (districts) of the third class, the area planted to wheat fertilizer conditions, high yield, processing quality, silty parameters, tensile performance of the parameters and starch pasting properties poor. (4) physical quality and milling quality wheat grain quality traits of grain bread surface color and appearance traits that directly affect the appearance of bread and structure formation, thereby affecting the total score of the bread. Protein content and gluten strength is conducive to the bread surface color, can increase the specific volume of the bread, and to improve its internal structure, significantly improved the total score of the bread, and high-quality bread dough extensibility and elasticity is relatively modest. Peak viscosity (B), starting thermostat gelatinization resistance (C), starting the cooling the gelatinization of resistance (D), cooling end gelatinized resistance (E) and 50 ℃ thermostat gelatinized in resistance (F) mainly by improving the surface of the bread color and toughness to improve the total score of the bread. Hematocrit is one of the key indicators of the evaluation of the quality of steamed bread, wet gluten content, tensile energy, land values, the maximum tensile resistance, bulk density, the damage value, grain hardness, water absorption of the bread specific volume impact, followed by the extent of its impact weakened direct impact on the effect of bread hematocrit largest tensile energy and tensile energy and bread specific volume was significantly positively related. Tensile energy forecast bread specific volume of steamed bread quality is better. (5) in the bread quality evaluation system, hematocrit and Texture Analyzer TPA test indicators hardness, gumminess, elasticity Reply sexual, chewiness was extremely significant with a positive correlation, L * and surface color was a very significant with a positive correlation, Elongation associated with height was extremely significant with negative textural properties (hardness * gumminess * chewing degrees) and the appearance of the characters and the internal structure was a significant positive correlation, smell and compression relaxation resistance (elastic * cohesion sex * Reply sexual) was significant with a positive correlation than content, L *, elongation, texture characteristics, compression relaxation, flexibility, adhesion bread quality evaluation of key indicators. Redistribution results, based on seven key indicators of the right to learn the principles and methods of construction of the wheat quality tasting bread quality evaluation system for hematocrit, L *, 25 points to 15 points, 10 points textural properties, adhesive 15 points compression Chang Chi resistance 15 points, 15 points of flexibility, elongation 5, total score 100-point scale. 22 Daejeon in 2009 to produce wheat samples to verify the material, and use of the results of the the GB/T17320-1998 standard sensory score and bread quality evaluation system for the classification of bread are basically the same. Bread quality evaluation system constructed to compare objectively reflect the quality characteristics of the flour, the results of the evaluation will be more reliable.
|