The study of the main impurities mature mash depending on the duration of fermentation, yeast alcohol race and used enzyme preparations

Abstract

The paper studied the process of intensification of concentrated fermentation mash with account of the complex amylolytic enzymes, hemicellulase and proteolytic activities. We determined the dependence of ethanol yield, the content of volatile impurities, the content of reducing substances, depending on the different strains of yeast at a seed rate 15 million cells per 1 cm3 wort. To identify the parameters of the fermentation process the wort with an increased solids content, investigated the dynamics of accumulation of volatile impurities by varying the rate and duration of seeding yeast fermentation using 987-O5 race yeast. It revealed that the qualitative composition of impurities in the mash, the resulting wort of high-concentration depends both on the duration of fermentation, and from normal seeding yeast. Thus, depending on the duration of the fermentation process, the acetaldehyde content increases (from 613,17 mg/dm? to 54 h to 1724,6 mg/dm? to 72 hours), the amount of ethyl acetate is reduced (from 409,2 mg/dm? to 54 hours prior to 207 mg/dm? to 72 hours), the methanol content to 54 h at a rate of 15 million yeast seeding cells per 1 cm? of the wort amounted to 0,0043 mg/cm?, whereas by 72 h of fermentation at the same seed rate yeast – 0,0070 mg/dm?, the amount of 1-propanol and 1-butanol was reduced from 903,14 mg/cm? and 6,38 mg/cm? -54 h to 880 mg/cm? and 5,57 mg/cm? - to 72 hours, respectively. The minimum content of isobutanol independent of the duration of fermentation was 900-1100 mg/cm? at a seed rate 15 million yeast cells per 1 cm? wort izoamilola number increases from 1219,08 mg/dm? (54 hr) to 2673,84 mg/dm? (72 h). It revealed that the smallest total amount of impurities obtained by seed rate yeast 15 million cells per 1 cm? wort at the duration of fermentation 54 hours was found that maximum ethanol content in the mash with minimal accumulation therein volatiles corresponds embodiment:. Duration of fermentation - 54 hours at normally the problem of yeast cells – 15,0 million / cm? wort.