Design And Optimization Of The Production Process Of Rice Jiaozi

Jiaozi, being a traditional leaven for cooked wheaten food in China, contains a series of microorganisms, such as Yeast, Molds, Lactic acid and Acetic acid bacteria. It can improve the quality of steamed bread because different microorganisms work together during the fermentation process. But the production process of Jiaozi sold in the market is various, the environment of its production is unstable, the quality of its product is unstable. The study aimed to optimize of the production process and to design a workshop as a reference to standardize Jiaozi production.The purpose of this study is to choose the best production processes by experiment, surveys and comparison on the different production processes. First, we obtain different levels of particle size of rice flour, additive volume of rice wine, Daqu, water, and the time and temperature of fermentation by single factor test to study the effecton the basic quality of Jiaozi. Second, the specific effects of various conditions on the count of Molds and the basic qualities of steamed bread were discussed by orthogonal experiments. Third, compare the properties of dough rheological fermentation, sensory evaluation of steamed bread and the content of flavor substance in term of the Jiaozi produced as the best process, sold on the market and high active dry yeast. Finally, we design a standard production workshop based on the best process to make a referenceto industrial production of Jiaozi. The detailed results of experiments were as follows:(1) The best production process is one supplement based on contrasting to six different processes and removing the useless step and composing the better measure. Stir and ferment slowly for 10hs.(2) The experiment of production process’s single factor showed that:the particle size of rice flour was 80 meshes; the additive volume of rice wine was 0.3-0.4 times (Based on the quality of rice flour, similarly hereinafter), the additive volume of Daqu was 0.03-0.04 times, the additive volume of water was 0.6-0.8 times, the fermentation time was 10-12h, the best fermentation temperature was 35℃.(3) The specific effects of various factors on Jiaozi and steamed bread quality and its influence degree is studied by orthogonal experiment’s range analysis and variance analysis. The result proved that the additive volume of Daqu had the most influence on the steamed bread quality and the final making process was concluded that the additive volume of rice wine was0.3 times (Based on the quality of rice flour, the same below), the additive volume of Daqu was 0.035times, the additive volume of water was 0.8 times, the fermentation time was 10hs.(4) The Jiaozi made by the best production process is better than that sold in the market and can substitute it by the comparison with dough rheological fermentation of Jiaozi made by self, sold and high active dry yeast, sensory evaluation of steamed bread and the content of flavor substance. From the test of volatile substance, we can that the Jiaozi steamed bread has much more content of volatile substance than that of yeast bread and its flavour also tastes better.(5) We designed a standardproduction workshop to provide a best process and a relatively stable environment, to ensure the quality of Jiaozi, to guide industrial production of Jiaozi based on the making process and contract. We combine the original workshop to build a new workshop.