| Yali pear (Pyrus bretschneideri Rehd cv. Yali) is one of the traditional Herb-Food-Homologous plans in China. In Hebei province, the output of Yali pear is immense, but the income of pear planters is relatively small. Perries are rich in nutrition, strong in aroma, and popular in each corner around the globe. In order to multiply processing approaches, add extra values, and thus get rid of the dilemma of Yali pear production, it is advisable that high quality perry be produced. But Yali pear alone can merely produce light-flavored perry, poor in quality.Mixed brewing is always considered as an important way to improve the quality of fruit wines. On the purpose of improving the sensory quality of Yali wine, understanding the fruit, yeast and fermentation technology effect on Yali wine, in this study,11 kinds of fruit were used as raw material, mixed respectively with Yali pear and fermented. The mixed parrie qualities were compared via sensory evaluation and principal component analysis (PCA), the aroma components wres analyzed via GC-MS and the anti oxidant activity were tested. Then the optimal yeast for hawthorn– Yali wine was selected from 3 industrial yeast, the optimal fermentation conditions of making hawthorn- Yali wine was explored by uniform design and response surface design methods. At last, one wild yeast strains, 3#, was screened out as hawthorn- Yali wine specific yeast, and dry yeast process of 3 # was studied. Test results are as follows:1. According to sensory evaluation and principal component analysis results, hawthorn- Yali wine with mixing ratio of 25:100 has the best sensory quality. The quality of grapes- Yali wine, plums- Yali wine, apples- Yali wine also has been improved, that means these 4 kinds of fruit are suitable to ferment with pear. The quality of Xuehua pear–Yali wine, Kiwi- Yali wine, Nanguo pear- Yali wine, jujube Yali wine, persimmon- Yali wine is degraded, which mesns these 5 kinds of fruit are not suitable to ferment with pear. Chi pear and Korla pear have No significant effects on Yali wine quality.2. When the mixing ratio of hawthorn toYali pear is equal to or lower than 25∶100,.the organic acids in the mixed wine is 4.16-7.94 g ? L-1, polyphenols is 0.18-1.35 g ? L-1, and perry quality will improve with the mixing ratio increasing. 3. The concentrations of polyphenols, flavonoids and oligomeric proanthocyanidins of juice are correlated with those of mixed perries. x1, y1 stand for the flavonoids concentration of juice and mixed perry, the regression equation is: y1 = 0.6337x1-0.0768, R2 = 0.9737. VC concentration of juice do not show significant influence on the one of mixed parries, x2, y2 stand for the VC concentration of juice and mixed perry, the regression equation is: y2 = 0.1578x2 - 11.832, R2 = 0.6857.4. The antioxidant capacities of 64 kinds of juice are significantly correlated to the ones of mixed parries.Testing the antioxidant capacities by FRAP method, x, y stand for the FRAP value, the regression equation is: y = 1.4666x - 0.307, R2 = 0.9368. Using KFe [Fe (CN) 6] method and DPPH method can get similar results.5. In Yali wine, hawthorn- Yali wine, grapes- Yali wine, plums- Yali wine and apple- Yali wine, ethylcaprylate is main aroma component, which means ethylcaprylate is characteristic aroma components of Yali wine.6. Danbaoli high active dry yeast can grow well in hawthorn- Yali juice, and the perry fermented by Danbaoli yeast has more aroma components and better taste, which mean Danbaoli is more suitable for Hawthorn- Yali wine fermentation than Oenoferm color active dry yeast and Angel high active dry yeast.7. The model between temperature (A), sugar content (B), hawthorn, pear juice, mixing ratio (C) to alcohol degree (Y) was established: Y = 9.16-0.19A+0.88B-0.22C+0.042AB+0.015AC-0.028BC-0.51A2+0.048B2-0.3C2. The optimum fermentation conditions is: temperature 25.18℃, 22.00% sugar, hawthorn pear mixture ratio is 21.19:100. In this condition alcohol is 10.05 (V / V%).8. To get more suitable yeast for Hawthorn-pear wine, 172 strains of wild yeast were isolated, after comparing of growth performance, ethanol production capacity, sensory evaluation, GC-MS analysis ,3 # strain were selected.9. By a single factor and orthogonal experiment, the optimum produce conditions of Alcohol-fermentation Active DryYeast of 3 # strain is determined: culturing in PD medium under 36℃, shaking for 48 hours, then centrifugation 20min with 4500R / m speed, collecting the yeast. 4% glycerol, 10% maltodextrin, 7% sucrose, 2% skim milk are mixed as a composite protective agent to blend with yeast, and then processed with low-temperature vacuum distillation .In this condition, the survival rate of yeast is up to 79.2%.
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