Extending The Shelf Life Of Chinese Steamed Bread Validation And Implementation Of Measures

This paper devoted to the shelf life of steamed bread in terms of practical production, exploring the manners of extending the shelf life in two ways, first of which was to improve the formula while the other was to improve the craft. We used single factor experiments, orthogonal experiments and response surface method analyzing the shelf life, sensory score, physical and chemical indicators and mold colony count. By combining the experiments in lab with production in factory,In the precooling of steamed bread production workshop design H2O2spray device, The20%H2O2will be sprayed by high-power air humidifier atomization,and it can be transposted by the PVC pipe which has some small holes. H2O2fog can be fully applied to precooling the workshop, spraying time is3-5s. In steamed bread packaging machine conveyor belt with9w uv lamp cover, the cover of the three sides have the uv lamp distribution, before and after the cover joint are connected by a soft canvas, guarantee the steamed bread before packaging to keep the clean environment, so as to extend the steamed bread shelf life.The conclusions were as following:1. By adding dehydroacetic acid calcium, calcium propionate and ascorbic acid into the formulas as3different antibacterial agents, we performed single factor experiments and orthogonal experiments. The results showed that the best products can be produced with0.015%dehydroacetic acid calcium(mass fraction),0.1%calcium propionate and0.18%ascorbic acid, steamed bread shelf life can be extended to80h.3antibacterial agents, dehydroacetic acid calcium influence the shelf life mostly, then the calcium propionate, last the ascorbic acid.2. We used hydrogen peroxide spray treating on the steamed bread, selecting hydrogen peroxide concentration, spraying time and production cooling time as variates to do single factor experiments and response surface experiments. The results showed that when the concentration was20%, spraying time was5s, production cooling time was50min, the shelf life, sensory score and TPA data would be respectively good, while the residual quantity of hydrogen peroxide also be in the safe scope, teamed bread shelf life can be extended to60h. According to the experiments, we selected the spraying time point as15min after the steamed bread been produced.3. The ultraviolet irradiation experiments showed that when the irradiation time was7s, UV light tube amount was3, the production quality could be the best, teamed bread shelf life can be extended to36h. Extremely irradiation treating data indicated that when the irradiation time extended to1h, the sensory score, shelf life and whiteness had no obvious changes.4. The concentration of20%hydrogen peroxide spray5s combined with ultraviolet sterilization ways to deal with steamed bread, steamed bread shelf life can be extended to72h, basic can meet the needs of the steamed bread production and sales in the summer.