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Beer is the world's most important low alcohol drinks wine. This paper studies the degree of fermentation, the wort α-AN levels, a small amount of malt used for brewing beer 8oP impact. The main results are as follows: one with 8oP Wort, using the following fermentation brewing four kinds of finished beer (fermentation, respectively 57.6%, 63.4%, 67.9%, 72.5%). Under the same conditions, the fermentation test and track the total acid primary fermentation process, pH value, α-AN, alcohol, sugar and the actual concentration changes. Fermentation lag are one day, down then up the total acid, pH value, α-AN, reducing sugar and the actual concentration decreased, alcohol gradually increased. Finished wine residues in α-AN increased with increasing degree of fermentation, the wort 12.3% ~ 19.4%; pH value decreased 1.79 to 1.89; total acid, reducing sugar content increased with increasing degree of fermentation, were 0.62 ~ 0.77mL/100mL 0.1mol / L NaOH and 3.2 ~ 4.80g / L. Turbidity increases with the degree of fermentation reduced chromaticity change little. Organoleptic shows the degree of fermentation was 57.6 percent, 8oP best beer flavor. 2 Using RP-HPLC detected nine major organic acids in beer and finished beer measured buffer capacity. Using statistical software SAS9.0 organic acid buffering finished beer the correlation between the analysis showed that lactic acid and cushioning significant correlation coefficient was -0.99008 (P <0.01); α-ketoglutarate acid were significantly associated with the buffer, the correlation coefficient is -0.96944 (P <0.05); fumaric acid, succinic acid and buffering in general, the correlation coefficients were 0.91313,0.93816 (P <0.10). 3 Using yeast nutrients will 8oP Wort content of α-AN adjusted 109.0,120.5,130.1,139.3,148.5,159.5 mg / L, brewer's yeast for fermentation inoculation, six kinds of finished beer brewing. Original gravity of 7.86 ~ 8.10oP between alcohol is 3.71 ~ 3.83% (v / v), real hair is 58.13 ~ 59.20%. SAS9.0 statistical results showed that α-AN and the original wort concentration, really thick, chroma significant positive correlation (P lt; 0.05); usually associated with reducing sugars (P lt; 0.1); with beer total acid (1.40 ~ 1.70mL/100mL 0.1mol / L NaOH) Average correlation (P lt; 0.1); beer and beer α-AN TN was a significant positive correlation (P lt; 0.01). Using gas chromatography beer flavor compounds (alcohols, aldehydes, ketones, esters, acids, hydrocarbons, etc.), and all the flavor and wort α-AN analysis of the relationship between the found differences butanol, iso-valeric and wort α-AN highly significant correlation (P <0.01); active amyl alcohol and isoamyl alcohol, heptanoate, bitterness, tetramethyl pyrazine with wort α-AN was significantly correlated (P <0.05); 3 - hydroxy -2 - butanone, acetaldehyde, heptanoic acid and α-AN wort usually associated (P <0.1). Display 8oP beer wort organoleptic α-AN content of 120.5mg / L when the optimum flavor. α-AN content of more than 130mg / L, the taste is still pure, but a special ester-like flavor, and a high diacetyl content. 4 0,5,10,15,20% proportion by wheatgerm for saccharification, and the resultant was adjusted to 8oP wort after analysis. Study found that as a small increase in the amount of malt, arabinoxylan, β-glucan contents increased, the viscosity increases, filtration rate decreases, reducing sugar and α-AN downward trend. Use SAS9.0 analysis found that the indicators and between indicators and the small amount of malt with a good correlation between. Each point on the curve saccharification sampling and analysis, when the study was 52 ℃ arabinoxylan highest (1556.25 ~ 1601.56mg / L); β-glucan at 78 ℃ was the highest (57.45 ~ 82.02mg / L); sugar content at 63 ℃, 72 ℃, 78 ℃ when the content is similar, at 35.08 ~ 37.29g / L between. 5 during mashing at 0%, 5%, 8.5%, 10% of the small amount of malt added wort prepared four kinds 8oP inoculated yeast for fermentation. Study found that a small amount of malt flavor in beer mainly substance alcohol, aldehyde acids, esters, organic acid formation had no significant effect; does not affect beer sensory indicators.
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