Figure 7

A model experiment demonstrates that the source of the glucose found in the distillate is cellulose. (A) Levels of glucose in a model distillate were measured every 30 min for 180 min during aging with a model substrate (wood chips) that had been treated with either a control solution (citric acid buffer; black dots) or a glucanase cocktail (white dots) (error bars are SEM). After 60 min, the level of glucose in the distillate interacting with the wood chips with reduced cellulose content was significantly lower than the control and remained so throughout the experiment. While not shown the treatment and control were statistically different with a 95% confidence interval at all time points. (B) The above experiment was carried out for a further 14 days, during which time the glucose levels of each of the model spirits were measured daily. In the system with the low-cellulose model substrate, glucose was significantly lower than in the control system throughout the experiment. While not shown the treatment and control were statistically different with a 95% confidence interval at all time points except at day 11. (C) Levels of cellulose in the model substrate that had been treated with a control solution (citric acid buffer; black bars) or a glucanase cocktail (white bars) before and after aging with a model distillate. The level of cellulose in the substrate treated with the glucanase cocktail was significantly lower than that of the control, and the levels of cellulose in both treatments showed a significant reduction after aging with the model spirit (Tukey-Kramer multiple comparison test P < 0.05, n = 6).