| Chinese steamed breads (CSB) as a kind of steaming fermented foods with distinct Chinese culture characteristics have been invented and improved by Chinese for about 2300 years. However, up to now, it has not reached the level of industrialization and modernization. CSB is the dietary staple food of many populations in China especially in northern China. Recently years, in northern China about 70% of wheat flour is used for CSB-making. At the same time, in southern China, the consumption of CSB has increased year by year. Compared with the achievement of western bread manufacture on a large scale and cereal or baking science, the production system and scientific research of CSB is at a very low level for a long time. Today, CSB production has the same trend with development of bread production in western countries.The goal of this paper was focused on some key points as follows: (1) Scientific classification of CSB by way of expertise investigation and fuzzy clustering analysis methods; (2) Establishment of sensory evaluation system for quality of staple CSB by means of expertise investigation and statistics methods; (3) Use of fractional factorial design and response surface methodology (RSM) to optimize processing procedure of harden type CSB; (4) Relationship among wheat flour quality and three types staple CSBs. (5) Effect of endoxylanases on dough properties and making performance of soften type CSB. The main contents and results as follows:1. This paper studied and obtained the scientific classification system of CSB for the first time. By means of comparisons between different results of phenomenological classification for CSB and conducting expertise investigation, the standards by ranks for CSBs' classification showed as three factors such as primarily usefulness, secondarily oral texture and thirdly shape and/or taste and/or flavor of CSB. And then we adopted fuzzy clustering analysis methods to discover the significant differences between different types CSB. As a result, CSBs can be classified into three major types, i.e. soften type, medium type and harden type CSB according to specific volume and hardness of different type CSB.2. This paper first time systematically studied establishment of sensory evaluation system for staple CSB quality. Based on the contrasting method between tow elements, a special expertise investigation was done and selected out 10 items of sensory quality parameter and tow items of physical properties parameter for evaluating CSBs' quality. And then by means of the other expertise investigation and derived statistics methods, the weight coefficients of every quality parameters for quality evaluation of different type CSB were obtained. Furthermore, the quality evaluation system was established respectively for three different types CSB.3. In order to establish the laboratory processing procedure for harden type CSB, a screening test of fractional factorial design was applied to weak, medium and strong flours to discover critical variables. As a result, only the medium and strong flours were suitable for harden type CSB-making. Furthermore, a Box-Behnken design and central composite design first time was conducted to study and to optimize the processing conditions for the harden type CSB. The considerable settings were established as optimallaboratory processing procedures for this type CSB. For the medium flour, first fermentation time: 36min; flour usage of main dough: 21-22%; flour usage of sponge dough: 52-53%. For the strong flour, times of pressing dough: 40-41times; flour usage of main dough: 23-24%; first fermentation time: 39-40min. The adequacy of the predictive models generated using the RSM procedure and reproducibility of the method for this type CSB were verified.4. Based on the results of classification of CSB, this paper studied the relationships between wheat 14 flours and CSB of 3 major types. Some significant correlations were found between flour quality and CSB quality. Protein quantity is an important factor effecting steamed volume. For soften type CSB, med...
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