Studies On The Low-Alcohol Beer Production

The low-alcohol beer with special flavor characteristic was produced in the research by changing the process, selecting the raw material and post-modification, without adding any distillation equipment. The main achievement were as follows:The Austrilian malt variety Schnooner with low nitrogen content, low WK, low (-glucan and low (-amylase activity, fresh rice, oligo-saccharide and transglucosidase were used as the raw material, in order to decrease the beer fermentation degree and alcohol content. At the same time, the additive such as tannin B, carrageenin and silica xerogel was used to improve the non-biological stability of final beer.In small-scale experiment in the lab, the (-amino nitrogen, iodine value and fermented sugar content in the wort was concerned about, the processing was firmed as follows: (-amylase and 30% rice was used, the ratio of malt to water was 1 to2.5, the temperautre of protein rest was 45℃, and then was raised to 74℃ quickly for starch saccharification, the time was 50 minutes. It was researched on the effect of adding transglucosidase and oligo-saccharide on the wort quality, respectively. It was found that if 0.1% transglucosidase was added before wort boiling, the wort temperature was 60℃, the action time was 60 minutes, the beer alcohol content was decreased by 47.4%, compared with the wort without adding transglucosidase; when the oligo-saccharide was added in the boiling wort, the wort fermentation degree and (-amino nitrogen content was decreased obviously, at the same time, the iodine value was increased greatly. It was concluded that the rice and oligo-saccharide using proporation was 15% and 20%, respectively, while the yeast nutrition was considered.The beer alcohol content and fermentation degree was the lowest, while the wort was produced with transglucosidase and G-03 brewing yeast strain, another was with oligo-saccharide and Y-5 brewing yeast strain in the small flask experiments. It was proved that there was no obvious difference about the physical and chemical index between the low-alcohol beer and common beer except with the low alcohol content and fermentation degree in the 20L EBC tube fermentation. The alcohol content was about less than 2%(v/v), the ratio of ester to high alcohol was about 1 to 2.8 and good flavor with adding oligo-saccharide processing.It was tested in large-scale production, with adding transglucosidase and G-03 yeast, adding oligo-saccharide and Y-5 yeast. It was found that the final beer alcohol content was about 1.98%(v/v), fermentation degree was 47.9% with adding oligo-saccharide. The beer flavor was good. The production cost was little more than the common beer. The enterprise would be brought a lot of money by this product.The post-modification technology was used on the low-alcohol beer. Many kinds of fruit beer were produced with low alcohol content and special flavor characteristic.