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Withering is an important process in the white tea processing, the withering the natural withering, duplex withering, and heating withering. 3 ways withering environmental parameters change its physical and chemical changes of fresh leaves not yet fully proven, natural withering, duplex withering long time, not suitable for rainy days, heating withering technology there is still instability in the hot air temperature the problem of inconsistent quality. In this paper, the introduction of air conditioning withering technology for the processing of white tea, air conditioning withering reasonable theoretically discussed. The withering way withering environment and natural, duplex, heating, air conditioning, four kinds of biochemical changes, color changes were determined and compared. (1) different ways the withering environmental temperature and humidity measurement results show that: the early spring, natural, duplex withering average temperature of 18-21 ℃, was \was \the biochemical changes, you need to the late Ottawa heap fermentation make remedies; environmental temperature and humidity of the air conditioning withering ranged between natural the withering and heating withering. (2) Temperature Humidity Index THI can be used for the expression \At low temperature, humidity, and the proper conditions, the temperature and THI associated larger; in the case of high temperature, humidity and small, humidity and THI associated. (3) heating the withering of the indoor and outdoor temperature and humidity was a significant positive correlation, therefore heated the withering room for heat should vary with the outdoor temperature and humidity changes, in order to stabilize the withering temperature; heating withering on the X-axis and Y-axis direction, temperature humidity and leaf temperature changes, the difference was not significant, but significant differences on the Z-axis direction; throughout the withering process temperature, relative humidity and leaf temperature difference was not significant. (4) The test results show that the rate of water loss in the withering process: white tea withering process of dehydration speed quickly at first and then slowly turning point to the critical water content was. The critical moisture content is different of the different withering way, withering the higher the temperature, the larger the critical moisture content, otherwise smaller. Different way of withering critical moisture were 28.67% of the natural withering, duplex withering 31.63%, 30.50% of the air conditioning withering, heating withering 36.17% 34.00% of the, cryogenic air conditioning withering climate withering 33.39%, 33.82% of the high-temperature air conditioning withering. (5) The experimental results show that the tea-like image acquisition: tea-like image acquisition of external conditions, about the size of 1.0MB, bright indoor open flash, the share of the thickness of the leaf to cover the backplane. Elevated R-value smaller before wilting and drying process; G values ??smaller first and then increased; B value has been reduced, R / G / B ratio has been increased. (6) The measurement results show that the biochemical composition of the tea samples: spring, throughout the withering process polyphenols, soluble carbohydrate content decreased, amino acids, flavonoids content; reduce summer season polyphenol content, amino acids, flavonoids, soluble carbohydrate content increased. (7) According to the fuzzy comprehensive evaluation method the white tea biochemical qualities Sort: spring: Duplex withering natural withering air conditioning withering> heating withering; summer season: low temperature air conditioning withering> high temperature air conditioning withering temperature air conditioning withering. (8) According to the fuzzy comprehensive evaluation method to to get of white tea biochemical and sensory quality sort :4-01 Mingqian tea: air conditioning withering the> heating withering natural withering, and the outcome of the review, exactly; 4-13 before rain tea: Duplex withering wither air conditioning withering heating withering with the outcome of the review exactly; the 7-26 summer tea: cold air conditioning withering climate withering> high temperature air conditioning withering, and the results of sensory evaluation of certain differences. (9) Application CFD heating withering environmental simulation results show that the air inlet at the age of air, temperature, humidity smaller; larger air vents at the age of air, the lower the temperature, high humidity.
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