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Blueberry fruit is rich in nutrients and prevent brain aging, cardiac, cancer, soften blood vessels, enhance immune and other health effects, FAO recommended five healthy fruit. Our blueberry planting late, but rapid development, therefore, should speed up the establishment of blueberries series processing technology. China had a planned economy period, it has emerged blueberry wine, but did not form the industrialization, and do not yet blueberry wine production system. Impact as test materials to the blueberry study different yeast fermentation process blueberry wine brewing quality and antioxidant activity. Blueberry wine dregs anthocyanin extraction process has been optimized to provide a theoretical basis for the production of blueberry wine and research base. The main findings are as follows: 1. Determination of the composition and content of the conventional physical and chemical indicators blueberry juice and organic acid component and sugar components. The results show that the relatively high acidity of blueberry juice, titratable acidity of 10.27 ± 0.13 g / L, pH value of 2.87 ± 0.02, citric its dominant acid (9310 ± 259.88 mg / L), about 90% of the total acid In addition, blueberry juice also contains large amounts of gluconic acid (4838.18 ± 121.10 mg / L), a trace amount of malic acid (103.1 ± 2.87 mg / L), oxalic acid (35.5 ± 3.12 mg / L), ascorbic acid (19.4 ± 0.69 mg / L), and a trace amount of fumaric acid (0.58 ± 0.02 mg / L). The blueberry juice total sugar was 79.94 ± 1.05 g / L, and the sugar component in the blueberry juice 1:1 fructose and glucose, sucrose is not detected. Apple juice and pear juice were used to study the factors that affect the production of fruit wine yeast glycerol. The results show that: (1) different yeast fermented cider glycerol content has very significant difference (P lt; 0.01), six kinds of yeast fermentation at 15 ℃ cider glycerol content of 4.42 ± 0.02 ~ 6.18 ± 0.07 g / L between; (2) the glycerol content of the cider the six kinds yeast fermentation at 20 ℃ were higher than 15 ℃, but Y2 glycerol production was no significant difference (P2 gt; 0.05); (3) Add 100 mg / L phosphate dibasic ammonium, Y1, Y2, Y3 and Y4 fermented cider glycerol content increased significantly (P LT; 0.05) than the control, Y5 and control (P5 lt; 0.05) was significantly reduced, Y6 reduced compared with the control was not significant (P6 = 0.312 gt; 0.05); (4) and 100 mg / L of SO2 added amount, add 150 mg / L SO2, Y2 and Y4 fermented cider glycerol content increased significantly (P lt; 0.05), Y1 , Y3 and Y6 increased significantly (P gt; 0.05), the Y5 significantly lower the (P5 lt; 0.05); (5) pear juice without adding a nitrogen source, add the the six kinds yeast and inoculated with 100 mg / L of SO2 at 15 ℃ The highest under fermented, cider perry the glycerol content were highly significant the the fermented cider glycerol content higher than under the same conditions (P lt; 0.01), in which Y2 fermentation of glycerol content, Y4 lowest Y6 fermented perry highest glycerol content, Y4 minimum. This knowledge, the fermentation temperature, the ammonium nitrogen sources add, have a certain impact of different doses of SO2 and fermented juice of the fruit wine yeast glycerol production, the different yeast affected the degree of different; within the scope of the study, the yeast strains, fermentation temperature and fermentation juice the yeast glycerol yield the greatest impact. 3 to 6 yeast fermented at 20 ℃ blueberry wine, preferably blueberry wine yeast. The results show that: Y2 blueberry wine fermentation highest glycerol content, up to 10.40 g / L, followed Y5 glycerol content of 9.74 g / L, Y2 and Y6 main leaven longest 41 days Y5 fermentation time is a minimum of 23 days, combined with the sensory evaluation results, the final choice Y5 blueberry wine brewing yeast strains. 4 to Y5 blueberry wine brewing strains to the pure juice fermented pomace common blueberry wine fermented two brewing process. The results show that: blueberry wine fermentation process, the total amount of acid and pH value increases; total phenolics and anthocyanins have different levels of loss, including the loss of anthocyanins higher than the total phenol, total phenolic pomace fermentation and anthocyanin loss rate (40%, 67%) were higher than the pure juice fermentation (31%, 46%). Leaven pure juice fermented blueberry wine (BW1), total phenols, anthocyanins, ferric ion reducing power (FRAP) and DPPH radical scavenging blueberry wine (BW2) were higher than the co-fermentation of pomace. Pure juice fermented blueberry Java (BP1), total phenols, anthocyanins, FRAP and DPPH radical scavenging blueberry residue (BP2) were higher than the juice pomace co-fermentation. Determine blueberry wine brewing process for pure juice fermentation at 45 ℃ pectinase enzymatic 2h juice, and then inoculated with yeast at 20 ° C under constant temperature fermentation. Correlation analysis showed that blueberry total phenol content of its iron ion restore force and DPPH radicals clearing rate has a highly significant correlation (r (the xy) = 0.999, P lt; 0.01), while the anthocyanin content correlation is not significant with (r (xy) = 0.539, P = 0.461 gt; 0.05). Blueberry wine types of organic acid component increases, to generate the blueberry juice excluding pyruvic acid, lactic acid, acetic acid and succinic acid, citric acid, gluconic acid, and ascorbic acid content decreased, malic acid, fumaric acid content increases, oxalic acid in the wine not detected. Your blueberry wine containing a small amount of fructose, glucose, rhamnose, xylose or arabinose, sucrose, does not contain other non-fermentable sugars. 5 to the blueberry wine byproducts blueberries slag as materials to study the of anthocyanins extraction process and stability. The results showed that the anthocyanins optimize the extraction process: the volume fraction of 1% of 70% hydrochloric acid in ethanol, solid-liquid ratio 1:25, extraction temperature 70 ° C, extraction time of 60 min. The extracted anthocyanins in the visible range of the maximum absorption wavelength of 520 nm, the same as blueberry juice; this pigment have a certain tolerance on the temperature; photolabile; oxidized reductant seriously affect its stability; VC will seriously damage its stability ; sucrose and glucose, its temperature stability is small; with the increasing pH value, chroma reduction.
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