| While China has come into a modern stage, people are concerning the questions about breakfast nutrition and overweight. The energy and nutrients from breakfast plays an important part among the dai ly need. No breakfast or low quality breakfast will influence daily intake of the nutrients and then their health condition, study performance and work efficiency. Overweight will cause inconvenience in the daily life and it is more concerning that overweight has been medically proved to link with diabetes and heart diseases. So the study on the development of the nutritional breakfast and slim food is worthwhile.Twin-screw continuous extrusion cooking technology is an advanced technology developed from the nineteen seventies, and it is the key and decisive function in the production upgrade of the breakfast cereals food. Even though the application of the cereals extrusion has been considerably researched, the mechanism of the twin-screw extrusion is rather complicated, and up to now there is not a complete, mature theory to explain the extrusion process, the quality control still depends on the experience. Many areas deserve to research systematically. For instance, the final quality influence of interactive function of raw materials during the extrusion process, the direct mathematic model of the operation parameter of the extrusion process related with product quality, and the interactive relation among different extruded cereals quality are not clear and need to further study. Meanwhile, the application range of twin-screw extrusion in food industry should be extended and further developed, besides the current wide use of production of breakfast cereals food, snacks, paste, instant flour, modified starch, texturised protein and food fiber.This thesis was to research nutritional breakfast cereals and tea slim cereals, by means of twin-screw continuous extrusion cooking technology. Three kinds of nutritional breakfast cereals were developed from all different kinds of cereals, and a tea slim cereals food was developed from tea, L-carnitine, dietary fiber as functional components, and corn meal as carrier. Systematically study on interactive influence of raw materials to the product quality during the extrusion process, and nutrition formula design of the breakfast cereals, operation parameter influence to the product quality, and the relationship among the quality standards of extruded breakfast cereals foods were conducted. Theoretical and practical meaning in the area of the development of extruded breakfast cerealsand research of the process of cereals food by twin-screw extruder was indicated. Formula for the extruded tea slim cereals food, and its toxic test and function were evaluated, which provided a new direction in the application of twin-screw extrusion technology in the food industry. The main results obtained are summarized as follows:1 Effects of breakfast cereals ingredients on the qualities of extruded cerealsThe effects of sugar, sweetener, fat, protein, dietary fiber and quality improver on the extruded cereals by twin-screw extrusion technology were discussed. Rice flour was used as the basic cereals ingredients in the experiment. Results showed that the structure of the extruded products became even and dense, the color was deepened, the flavoring was fortified, the expansion rate and water solubility index (WSI) were increased, water absorption index (WAI) was not changed much when l%-5% reduced sugar was added into rice flour. Sucrose more than 8% could restrict the expansion rate, increase the crispiness, decrease WAI, but not change WSI much. The less amount of fat, soy protein and dietary fiber could improve the quality and its nutrition of extruded product. Soya lecithin and calcium carbohydrate may be used as the quality improver of extruded cereals.2. The formula design of the extruded nutritional cereals foodBased on the analysis of the raw material property and linear programming theory, the nutritional requirement of the product and the limit of the raw material extrusio... |
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