Studies of the effect of secondary beet molasses constituents on the quality of baking yeast – Part 1: Introduction and methodology

Owing to the fact that beet molasses contains about 48% sucrose as well as various organic and inorganic compounds essential for fermentation and the oxidative yeast metabolism, it continues to be frequently employed as a raw material in the food, chemical and pharmaceutical industries, thanks also to its cheapness. The quality of molasses is, however, adversely affected by the growing use of technical aids and additives in sugar manufacturing; it has an increasing content of additive residues, nonassimilable components and nonsugar substances. The consequences are poorer molasses quality, longer processing times, yield losses, higher production costs, and negative effects for the metabolism or fermentation as well as the quality of the baking yeast (premature yeast softening). Industrial experience lays responsibility for this on the residues of additives used in the sugar industry (antifoaming agents, disinfectants, flocculants, antiscaling and wetting agents). Not defined, however, is the chemical constitution of these compounds, since technical aids are extremely complex in composition and subject to change or hydrolytic breakdown in the course of sugar processing. The content in beet molasses of ethoxylated surfactants (6-30 ethylene oxide groups) registrable by the bismuth active substances (BIAS) method has greatly increased in recent years.