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According to the problem of bread in our country, which were that bread quality was not good enough and bread was aging easily during storage, we studied on bread improver, who had the function of improving bread quality and inhibiting the aging of bread, in order to solve the key technical problem of bread industry. This paper was studied on bread, probe into the improving influence of different kinds of antioxidant, enzymes, thicker and emulsifier alone or composite using in bread. The texture parameter, hematocrit, yield rate, moisture content and water activity of bread core were researched, we got a bread improving formula, which could obviously delay the aging and improve quality of bread. From these studies, we can make conclusions as following.We selected different kinds of antioxidant, enzymes, thicker and emulsifier monomer, and then toke some single factor experiments, to make sure the influence of single additive adding to bread. Some conclusions were made from these experiments, and the results were showed as below: (1) Ascorbic acid could increase bread hematocrit and delay the aging of bread when it was in a certain adding range. (2) In their adding range, turn glutamine enzyme and lipase could increase the hematocrit of bread, slow down the speed of bread aging. Glu-cose oxidase had an obvious influence to increasing bread hematocrit. In the adding range of 30ppm~50ppmof fungi amylase, the bread hematocrit was increase first and then drop as the adding amount increasing. When the adding amount was more than 40ppm, fungi amylase could reduce bread aging speed significantly. Fungus xylanase had no improvement function on bread quality. In addition to lipase, all the selected enzyme had negative influence to the function of water maintain. (3) All the selected colloid could reduce the bread hematocrit and increase the yield rate in the adding amount range of 0.05%~0.15%. As the adding amount increasing, the function of delaying aging of xanthan gum, carrageenin, gelatin and arabic gum were much clearer. Within the suitable adding range, sodium alginate could delay the aging speed of bread. Guar gum could increase the hardness of bread, and this phenomenon was clearer as the adding amount increasing. (4) Glycerol monostearate, SSL and CSL had the function of delaying aging of bread. Glycerol monostearate, SSL could increase the hemato-crit and yield rate of bread much better than CSL. We selected some single additives, which could delay the aging of bread significantly, to make composite adding tests. The results of experiment were showed as bellow: (1) Selecting any two of the glucose oxidase, turn glutamine enzyme and lipase to make combination add-ing tests, all enzyme combinations could delay the aging of bread. In later stage of storage, the elasticity and moisture of bread core were maintained by any enzyme combinations. (2) The combination of sodium alginate and gelatin could effectively delay the aging of bread and maintain the elasticity of bread in later stage of storage. Sodium alginate and xanthan gum could maintain the elasticity of bread in later stage of storage, and make bread achieve an ideal storage condition of high moisture and low water activity. The combination of xanthan gum and gelatin can effectively delay bread aging, but would weaken the bread elasticity maintain ability. (3) Adding compound emulsifier to bread could make the speed of bread ag-ing slow down and the elasticity of bread in later stage of storage is maintained. It also could reduce the moisture of bread’s losing, and had positive influence to delay the aging of bread.We choose the texture parameter, moisture content and water activity as optimization experiments’determination index, and then made comprehensive evaluation to determination results, got an optimization formula of bread improver. The formula was show as that, ascor-bic acid 0.04%, CSL 0.10%, SSL 0.10%, glucose oxidase 10ppm, turn glutamine enzyme 20ppm, xanthan gum 0.05%, gelatin 0.05%.Through comparative trial between optimization and some good bread improver in mar-ket, we found that the optimization formula had better improving effect to the aging, elasticity, chewiness of bread than the market formulas.Studying on the way of packing and storage of bread, we found that storage under room temperature could effectively maintain the quality of bread; especially the no inflatable sto-rage had better effect. Because of bread is soft and easy extrusion deformation during trans-port process, it need filling with air during packing to maintain a perfect appearance shape. Comprehensive consider of it, we choose inflatable packing and storage under room tempera-ture.
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