| Tea is one of the important economic crops, which is dating back more than3000years of history. The tea is widely distributed in china. Chinese tea plantation area and production of China are up to the world. Tea contains a variety of active ingredient that human needs, which enhanced immune function of the body effectively. In order to meet the requirements of modern society. The production and consumption of instant tea has been unprecedented developed. The characteristics of instant green tea were healthy, fast, convenient, health, taste, Which meet the the modern beverage consumption fashion. In recent years, actively instant tea have been processed and researched by internal and external numerous enterprises and research departments. Instant green tea production of raw materials come from the finished tea or fresh tea leaves. Currently, the rural labor force have been tightly and the mechanical harvest tea technology have became maturely. Therefore, the amount and scope of the mechanical harvest tea will become more and more greatly. It is difficult to process high-grade green tea with the machine, fresh tea does not pay attention to the shape of the machine processing of fresh tea is a good way, but also the future trends. However, there are many questions in mechanical harvest tea fresh leaves: coarse, contains more tea stems,feeding difficulties, fixing uneven impervious, extracted inadequate and so on. Yet, the applicable equipment of instant green tea process is so serious shortage, which has been unable to meet the needs of rapid development of China’s modern tea industrialization, and which seriously has hampered the further development of the tea industry. It is very necessary to research and develop the new applicable machine and production technology of machines harvest instant green tea. In this paper, it introduced the research and development of the processing technology and key equipment of machines harvest tea from the instant tea production reality and providing technical support for instant tea processing.Specific research content includes the following sections:1. Research on the crushing processing technology and equipment of machines harvest tea. According to the problem of crushing processing operations of machines harvest tea, it is researched and developed two new tea crushing process technology and equipment, according to being based on the current new crushing processing technology.1) Research on the rolling cutting machine with Conveyor belt feeding. It is optimized the design of the structure and the key components of the machinery. According to the actual production, it is finished the selection and optimization test in the main factors of affecting the tea guillotine cutting. It is determined the order of primary and secondary factors to affect the tea chopped qualified rate, production and unit energy consumption. Finally, it is obtained the best combination of process parameters. The factors affecting the tea guillotine cutting reached a significant level by variance analysis. Through the production test, the performance of the equipment can meet the design requirements.2) Research on the technology and equipment of tea combined grinding. It is achieved the structure design, optimization of process parameters and the comparison test of production performance in the disc cutter guillotine cutting device and hammer crushing device of the unit, to obtain the best structure and process parameters. Analyzed the features and advantages of the technology of twist knife cutting and hammer grinding, the first time these two technologies complement each other, to realize the integration and breakthrough of the crushing technology in the long-fiber, higher water content materials(such as machines harvest tea). To solve a technical problem for our country tea crushing technology, it is showed a strong technological advantage and a production practicality. Through the production experiments and applications, the design of structural parameters of the unit is rational, and the performance indicators of crushing operations meet the design requirements. So it have the characteristics of a safe, reliable, high productivity, and low energy consumption.2. Research on the tea fixation processing technology and equipment. In response to the problems of mechanical harvest tea fixing uneven impervious, it is researched three equipments and techniques of tea fixation operations based on the current tea fixation technology.1) Research on the comparative test of the hot-air-steam combination fixing. It is obtained the comparison experiment of microwave fixation, steam fixation, hot-air fixation, pot banknote fixation and hot air-steam combination fixation. Through the comparison in sensory assessment of the different fixation, determination of the inclusions, technical characteristics and economic, it is achieved the hot air-steam combination fixation has the highest score in the sensory assessment, which keeps more tea inclusions. However, the device structure is complex, first-cost is high, fixing costs much and leaf temperature is difficult to control.2) Research on the technology of microwave-far infrared combination fixation. By optimizing experiment, the optimum process parameters and the main influencing factors have been gained. By comparing belt microwave fixation, roller microwave fixation and far-infrared fixation, it was found that microwave-far infrared combination fixation technology had the highest score after sensory quality. Except the color appearance score slightly,the rest of the sensory quality were good. By fixation tea compounds were measured, the remaining components were higher than other fixation components, in addition to the content of tea polyphenols and catechins which were slightly lower than the microwave fixation. This study was to combination the advantage of microwave fixation and far infrared fixation technology. It overcome the lack of use of simple microwave fixation.3) Research on the tea roller microwave fixation technology. Tea microwave roller has been designed through the optimized design of the microwave roller structure and motion parameters. Through orthogonal test and organoleptic evaluation,organoleptic evaluation the optimum as being founded. Organoleptic evaluation score is the highest. By determination, Amino acids, caffeine and tea polyphenols content were higher than microwave fixation, far-infrared fixation, far infrared-microwave combination fixation. These were showed the more advantage of tea roller microwave fixation technology.3. Research on the processing technology of mechanical harvest green tea main composition extraction.According to the characteristics with three problems, which were extracted with time-consuming and low yield in main composition of tea extraction, which was difficult to achieve the desired effect by single extraction technology or traditional water extraction. In order to solve this problem, the equipments and processes of the two tea extraction has been researched and developed.1) Research on the technology of microwave-ultrasonic combination extraction. The tea extraction technology program has been determined by the combination of microwave and ultrasonic extraction technology. The main factor of microwave-ultrasound combination extraction has been analysised. Based on single factor test, main influence factors and the optimum extraction process parameters was investigated using an orthogonal design. It was the better than microwave-ultrasonic combination extraction, compared with traditional water extraction test. This shows the more technological advantage of microwave-ultrasonic combination extraction.2) Research on the process of ultrasonic assistant extraction tea polyphenols. The ultrasonic had unique mechanical crashing and cavitating reactions, which can be used in extraction of Tea-Polyphenols from Tea. The main influence factors in Ultrasound extraction and the optimum parameters of extraction obtained by using ultrasonic assistant extraction testing. The results on compared with the traditional method of hot-water extraction, show that the extraction time is shorter, the temperature is lower, the number is less in under the same extraction condition. The test can save time4/5in comparison with the traditional method of hot-water extraction. |
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