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In this paper, free and immobilized Aspergillus niger (Aspergillus niger) cell fermentation technology for the production of liquid ginkgo tea, ginkgo liquid for functional development of tea drinks a preliminary exploration of the ginkgo fermented tea quality changes before and after fermentation, functional ingredients changes in biological activity, and free fermentation with immobilized fermentation were compared on the basis of a preliminary study of environmental factors on the impact of the fermentation system. The results showed that: Ginkgo tea by microbial fermentation liquid, color, smell and taste were significantly improved. Original Ginkgo biloba green gas, Smell disappeared, bitter taste decreased significantly, the soup turned by the bright yellowish amber, with a clear fruit sweet, refreshing taste of alcohol, long-term storage at room temperature, no precipitation deterioration and other produce. In order to investigate the mechanism of change in the quality of the research carried out by the aroma extracts of activated carbon adsorption headspace adsorption method, using the Curie point heating pyrolysis, and then GC-MS qualitative and quantitative analysis. The results showed that some of the high-boiling alcohols aromatic substances such as benzene, methanol, benzyl alcohol, linalool and its oxides increased in varying degrees, on behalf of taste, flavor substances Chan indole and propanal content was significantly reduced. By chemiluminescence antioxidant activity of Ginkgo biloba tea was found after fermentation greatly improved its biological activity. Ginkgo flavonoids in tea HPLC analysis showed that the composition of the fermentation broth of bitter components flavonol glycosides were significantly decreased, while flavonols content increased. Initially proved in Aspergillus niger secreted β-glucosidase under the action of ginkgo tea flavonol glycosides glycosyl are dissociated, the degradation of flavonols. Structural changes in flavonoids, phenolic hydroxyl broth increase in total (including 3 `-bit, 4-bit and 3,5,7 'bit), ginkgo tea is fermented antioxidant capacity increased mainly, but also by the fermentation After the taste quality improvement of the important reasons. To enable the products to industrial production, the study of the production process for a preliminary exploration, through contrast, found that the optimum immobilized fermentation temperature is 32 ~ 36 ℃, optimum speed is 90rpm. In addition, compared with the free fermentation immobilized particles can be adapted to high concentrations of growth, but in the fermentation process, pH can be maintained at a more stable state, which is the technology used in industrial production advantage. Made on the basis of the study, this paper first proposed the \the direction of the transformation, get nutrition, function, quality and taste of the product, will be the future production and development of functional foods in an important way.
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