5120
Salah Hamza Elmahdi Salem
STUDYING THE EFFECT OF MICROBIAL CONTAMINATION OF BAKER'S YEAST ON ITS BIOLOGICAL BEHAVIOR
BAKER'S YEAST, MICROBIALCONTAMINATIONm
Baker's yeast is one of the oldest products of industrial fermentation. Ancient Egyptians used it for bread making since 6000 years ago. Baker's yeast formulation grouped into two main types; compressed yeast (30 % solids) and dried yeast (about 92% solids) both are produced in a large fermenters by the fed- batch process on cane or beet molasses. Bacterial contamination in industrial yeast production is a huge problem. The contaminating bacteria can provide added value in the form of flavor and taste also can negatively affect S. cerevisiae by execrating inhibitory substances or at least compete for the same substrates. Possible sources of contamination may be attributed to the packing line equipment (e.g. conveyors and dosing cups), packaging material or the workers as well as the raw materials used in the manufacture of commercial yeast which are rich in nutrients and are thus excellent substrates for microbial growth.
2016
Ph.d
Al-Azhar
Science