The alcoholic ferment of yeast-juice. Part III.-The function of phosphates in the fermentation of glucose by yeast-juice

Abstract

In a previous communication the authors have shown that when a soluble phosphate is added to a fermenting mixture of glucose and yeast-juice the following phenomena are to be observed: (1) The rate of fermentation is at once greatly increased. (2) This acceleration lasts for a short time and the rate then falls off, and returns approximately to its original value. (3) During this period the extra amount of carbon dioxide evolved and alcohol produced are equivalent to the phosphate added. (4) The phosphate is converted into a form which is not precipitable by magnesia-mixture, and is then probably present as a salt of a hexosephosphoric acid. (1) Effect of the Addition of Phosphate on the Total Fermentation . The addition of phosphate, however, does not simply produce this initial decomposition of an equivalent of glucose, but also, as a rule, a greater total fermentation, after allowance has been made for the amount decomposed during the initial period.