Study On Multi-fermentation Mode Of Liquor Distiller’s Grains

Distiller’s grains as the main by-product of the Luzhou-flavor liquor account for10%to20%of the number of maternal fermented grains. There are many incompletelyutilized nutrients remained in distiller’s grains. Therefore, it is still a challenge tomaximize the re-use of distiller’s grains in the field of wine industry. Herein, a newfermentation model, multi-fermentation is developed, which has the advantages ofstacking fermentation and aroma-producing by the zymic distiller’s grains in Maotaipits. It can not only improve the value in use of distiller’s grains, but also produce newhigh-quality base liquor.Firstly, the models of stacking fermentation (the indoor open stacking fermentation)and the pit entry fermentation (the inclosed fermentation into the Luzhou pits) bothbelonged to multi-fermentation were determined through the single factorexperiments.Furthermore, according to orthogonal experiments, the optimumfermentation period and fermentation model is determined. The indoor open stackingfermentation time is4days, and next the fermentation time into Maotai pits is35days.Secondly, the conditions for distiller’s grains fermentation were optimized by thesingle-factor tests and orthogonal experiments: the indoor open stacking fermentationtime is4days, the medium temperature starter is26kg per steamer, the yellow water is19kg per steamer, the fermental liquid is28kg per steamer, and the fermentation timeinto Maotai pits is38days. After fermentation, distilling fermented Grains by using theG1(660kgper steamer) reflux liquor in order to extract flavor components.Lastly, the storage stability of new craft liquor of distiller’s grainsmulti-fermentation was studied. The70%vol~75%vol of new craft liquor is as thestandard of storage.Research results:①T he analysis on the number of microorganism through pre-and post-thedistiller’s grains multi-fermentation showed that the number of microorganisms throughindoor open stacking fermentation and the inclosed fermentation into the Maotai pitsincreased substantially. And the time of pit entry fermentation is relatively shortened for15days.②The test of reflux liquor by distilling fermented Grains to extract flavorcomponents showed that the sensory index score of base liquor was increased about1.5. These results implicate that the potential applicability of multi-fermentation methodfor the improvement of the quality of the base liquor in the field of wine industry.