The Effect Of Natural Additives On Bread Quality Of Different Wheat Flour

In recent years, with the adjustment of industrial structure, wheat production situation of China hadchanged dramatically, but the structural contradiction between wheat varieties, and the big gap withinternational high quality wheat still exists. Although wheat advantage region had formed basically,there are still the irrationality of structure and scale, and the wheat quality is not stable. This studyselected Shiluan02-1, Shiyou17, Aikang58and Jimai22which were extended widely and used asexperimental materials. Gluten, vitamin C and soybean flour were added to wheat flour to investigateeffects on baking quality and dough properties of different wheat flour. The main results as follow:1. In order to understand wheat protein quality status in China in recent years, the trend of wheatprotein quality and developing direction was discussed,4235wheat samples collected from the mainwheat provinces during2004-2011were analyzed for protein content, wet gluten content andsedimentation value. The result showed that protein content and wet gluten content had no obviouschange, however, sedimentation value declined slightly from2004to2011; The protein quality indifferent main wheat provinces was quite different, Higher in the north and east places. Indicating thedecline of wheat quality, the widespread plant of the varieties with high yield had affect the overallquality of wheat seriously in China. Development of high yield wheat varieties quality with high qualityshould be focused according to different area conditions.2. To investigate the improvement effect on bread baking quality of different wheat flour and toprovide theoretical basis for the flour factory to improve all sorts of flour produced in China, four wheatcultivars,Shiluan02-1, Shiyou17, Aikang58and Jimai22were tested by adding gluten with the level of0%,1%,3%,5%,7%and9%.Physical and chemical property tests showed that the gluten additionincreased the volume of bread rapidily, improved function on the sensory characteristics in a certainrange. However, too much addition caused empty bread core and other adverse effect. Different flourhad different optimal addition levels. The most appropriate addition quantity to Shiluan02-1, Shiyou17,Aikang58and Jimai22were1%-2%,3%-5%,7%and9%respectively.3. To investigate effects of the Vitamin C on baking quality and dough properties of different wheatflour, four wheat cultivars, Shiluan02-1, Shiyou17, Aikang58and Jimai22were used as materials fortesting of the effect. The result showed the Vitamin C had significant effect on the bread volume ofShiluan02-1, Aikang58and the effect varied with cultivars. Adding of the Vitamin C had no effect onbread structures including bread appearance, colour, texture and structure. The effect of adding VitaminC on rheological properties of wheat flour was limited and varied with cultivars. Adding of Vitamin Ccould not change the properties of wheat end use.4. To investigate effects of inactivation and bioactive soybean flour on baking quality and doughproperties of different wheat flour, four wheat cultivars,Shiluan02-1, Shiyou17, Aikang58and Jimai22 were tested by adding soybean flour with the level of0%,1%,3%,5%,7%and9%. The result showedthat weaker the flour was and smaller effect from soybean flour occurred, and only bioactive soybeanpowder improved the stability time and weakening degree of strong and moderately strong gluten wheatflour; The addition of bioactive soybean powder could increase the bread volume of middle stronggluten flour, while inactivation and bioactive soybean flour both had no improved function on the breadbaking quality of strong gluten and weak gluten wheat flour.5. To investigate the nutrition reinforcement of bran and whole soybean flour to bread, the stronggluten wheat flour Shiluan02-1was tested with the addition proportion of5%and10%. At the sametime, the methods of SHS and HS-SPME method, together with mode of splitless and split with the ratioof5:1were compared to analyse the flavour compounds in bread, finally, HS-SPME and split modewere chosed. Replace wheat flour with5%of wheat bran and5%of soybean flour respectively toanalyse the effects to bread flavor compounds. The result showed that the bread protein content, crudefiber content and parts of amino acid level increased obviously as the bran or whole soybean flour’saddition, and strengthened the role of nutrition.87compounds were detected in wheat bran bread, andthe total content decreased by11.36%, while the main flavor compounds increased which made the branbread rich more aromas.89compounds were detected in soybean bread, the total content increased by9.89%, and almost all compounds content that affected bread flavor had different increase.