| Consumers are increasingly pursuit of a healthy lifestyle with the development of economic. Low-sugar (or sugar-free) & low-calorie foods, which has lower residual sugar and calories, is favoured by many consumers. Therefore, research of low-sugar (or sugar-free) & low-calorie foods has been a hot trend, this paper developed sugar-free & low-calorie beer. The results of research were as follows.Yeast which had high degree of fermentation was screened with ultraviolet mutagenesis method and anti-glucose repression. The beer real degree of fermentation reached 74.54%, which increased by 7.05% compared with the original strain.This paper determined the operating parameters in saccharification when wort limit degree of fermentation as the index, which based on the relationship between the beer degree of fermentation and wort limit degree of fermentation. The results showed that the optimum operating parameters was that malt crushing roller spacing was 0.2 mm, the ratio of material to water was 1:4(w/v), glycosylated pH was 5.0-6.0, saccharification temperature was 63℃, feeding temperature was 45 ℃. Meanwhile, improving the time of saccharification and adding enzyme could greatly improve wort limit degree of fermentation.This paper studied the effects of fermentable sugar on wort limit degree of fermentation. The results showed that adding the fermentable sugar could improve wort limit degree of fermentation. The saccharification process was determined through the orthogonal experiment, the results was that:saccharification time was 2 h, the ratio of wort to the same concentration of sucrose solution was 2:5, and adding glucoamylase and pullulanase were 3000 U/g malt and 20 U/g malt respectively. Wort limit degree of fermentation in this condition reached 91.35%. Comparison of five kinds of nitrogen source showed that adding ammonium chloride of 0.93 g/L could successfully solve the lack of nitrogen source problem in wort because of adding too much sucrose. At the same time fermentation broth dilution could make original gravity decrease to 5.25℃.The 200 L test of sugar-free & low-calorie beer in this paper showed that physiochemical indexes of beer meet the requirements of light beer, ratio of alcohol to ester was 7:1. Meanwhile sensory evaluation showed that taste was coordinate and sweet aftertaste.The market prospect of sugar-free & low-calorie beer is broad because of its lower residual sugar and calorie. Sugar-free & low-caloriebeer was studied by screening of high attenuation yeast, determining single factor operation parameters and the brewing process. Physiochemical indexes of the beer was normal, ratio of alcohol to ester was reasonable, and the taste was very good. The reseach had certain practical significance for the development of beer products. |
