| The crux of maintaining the persimmon industry developing steadily and healthily is to enhance its benefit keeping pace with the increasing of persimmon quantity and the development of persimmon industry. Now that the products of acetic acid fermentation have good market vista. The research stand on the natural strain and traditional technology of processing vinegar of persimmon. Rounding the core of improving the quality of flavor of the vinegar of persimmon. Applied basic method of microbial separation and identification to screening yeast and acetobacter acetic which suitable for brewing vinegar of persimmon, the work lays a strain foundation for producing vinegar of persimmon. Study on Physico-chemical changes in aging process, the work lays a theory foundation for researching aging technology. Revealed mainly characteristics composing component of fragrance of vinegar of persimmon, providing reference for establishing quality evaluated system of vinegar of persimmon.Mizukaki which yielded in Yang Ling taked to be raw material, fermented with no added microbial strain, separation and identification superior yeast and acetobacter acetic. Aging vinegar of persimmon after fermented accomplish under different temperature conditions during 180d, determination content of soluble solids and total acid and scanning absorption wavelength and its value. The flavoring compositions in Vinegar of Persimmon were extracted by solid phase micro-extraction (SPME) and was separated and analyzed by GC-MS, and contrasted fragrance of vinegar of persimmon aging in different conditions. Obtains the following conclusion:1. The solid-fermenter of Vinegar of Persimmon virgin pulp with no added microbial strain is tested in this experiment. Isolation, Screening of Yeasts, on base of satisfying requirements of brewing persimmon vinegar, but more emphasizes the performance of producing fragrant. Obtained one strain (JM2), this yeast is good at the performance of producing fragrant and typicality. According to observation of the morphology, the way of sexual reproduction, fermented sugar, assimilating carbon source, assimilating nitrogen source, growth in the 50% yeast extract, growth in 37℃etc. Compare to the decription of The Yeasts: a taxonomic study (3rd edition). In the end, this superior strain belongs to Kluyveromyces. JM2 was characterized as Kluyveromyces marxianus.2. The solid-fermenter of Vinegar of Persimmon virgin pulp with no added microbial strain is tested in this experiment. As to its inside acetobacter acetic, adopting the changing colour circle method to separate acetobacter acetic, then through early screening and second screening, finally according to the quantity of producing acid the author got one superior acetobacter acetic (Af6). The morphology, cultivation, physiology, biochemistry were tested for identification. In the end, this superior strain belongs to Acetobacter. Af6 was characterized as A. rancens.3. Aging Vinegar of Persimmon after fermented accomplish under different temperature conditions during 180d, study on Physico-chemical changes in aging process: All the soluble solids content of samples showed decending trend. Acid content of sample G1 and G2 showed rising trend and the rest decreased. After aged 180d, acid content of samples aged at 3-6℃is more than aged at 30-35℃. Centrifuged samples aged in 30-35℃, maximum absorption wavelength increased, centrifuged samples aged in 3-6℃, maximum absorption wavelength decreased. The range of absorption wavelength of sample Y1, Y2, Y3 and Y4 reached most widely when aged the third month, sample Y5, Y6, Y7 and Y8 reached most widely when aged the fourth month.4. Aging Vinegar of Persimmon after fermented accomplish under different temperature conditions during 180d. The flavor components in Vinegar of Persimmon were extracted by solid phase micro-extraction (SPME) and was separated and analyzed by GC-MS. About 63 different compounds were identified in the flavor components in Vinegar of Persimmon aged at 3-6℃; About 65 different compounds were identified in the flavor components in Vinegar of Persimmon aged at 30-35℃.All including acids, alcohols, aldehydes, ketones, esters, phenols,hydrocarbon and other a few compounds. Alcohols, esters and hydrocarbon in the flavor components in Vinegar of Persimmon aged at 30-35℃is more than in Vinegar of Persimmon aged at 3-6℃; Acids aldehydes, ketones and phenols in the flavor components in Vinegar of Persimmon aged at 30-35℃is less than in Vinegar of Persimmon aged at 3-6℃.
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