If fruit juices or sugar solutions are left to stand in the open air, they show after a few days the processes which are covered by the name of fermentation phenomena.

If fruit juices or sugar solutions are left to stand in the open air, they show after a few days the processes which are covered by the name of fermentation phenomena.

The initiation of the fermentation process does not require so complicated an apparatus as is represented by the living cell. The agent responsible for the fermenting action of the press juice is rather to be regarded as a dissolved substance, doubtless a protein; this will be denoted zymase.

We allowed ourselves to become particularly interested in research into the appearance of intermediate products of sugar decomposition during cell-free fermentation.