One of the main factors affecting the quality of bread are microbiological and biochemical processes occurring in dough semifinished products as a result of yeast activity. These processes can be controlled by regulating the biotechnological characteristics of yeast, 
which allows to intensify technological operations of baking production. Baking yeast should have high enzymatic activity, the ability to release 
carbon dioxide in anaerobic conditions and quickly adapt to changes in the composition of the nutrient medium. These properties of yeast can 
be improved by pre-activation in nutrient media containing components that intensify the synthesis of fermentation enzymes in yeast cells. The 
aim of the work was to study the effect of pre-activation of pressed baker's yeast Saccharomyces cerevisiae in nutrient media with food complex 
additive on their biotechnological characteristics: lifting force and enzymatic activity (zymase, maltase). Yeast lifting force was determined by 
accelerated method. Zymase and maltase activities were determined by measuring the time for which 10 cm3 of carbon dioxide is released 
during digestion of glucose and maltose solutions by yeast, respectively. The novelty of the work consists in the establishment of parameters 
of preliminary activation of baker's yeast Saccharomyces serevisiae with the use of food complex additive. It is shown that the optimal duration 
of yeast pre-activation is 20 min. Pre-activation of pressed yeast contributed to the increase of their biotechnological characteristics: yeast 
lifting force increased by 46.9 %, zymase activity - by 37.7 %, maltase activity - by 13.4 %. The obtained results indicate the promising 
application of yeast pre-activation in nutrient medium with food complex additive in the production of bakery products

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