Volume 6
Issue 1
Biotechnology
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
Available Online: http://www.ejpau.media.pl/volume6/issue1/biotechnology/abs-03.html
STUDIES ON YEAST EXTRACTS ENRICHED IN 5´NUCLEOTIDES FLAVOUR ENHANCERS OBTAINED FROM SPENT BREWERY YEAST
Antonina Komorowska, Bogdan Sieliwanowicz, Ewa Mrówka, Krystyna Stecka, Aurelia Hałasińska
ABSTRACT
The aim of the research was to develop a method of obtaining yeast extracts to the needs of food industry. The yeast extracts were enriched in nucleotide flavour enhancers (5’-GMP and 5’-IMP) obtained from brewery spent yeast. The influence of the directed brewery yeast cell autolysis, preceded by ultrasonic yeast cells’ disintegration and a cytolytical enzymes complex (Lyticase), 5’- phosphodiesterase (5’PD) and 5’-adenylic deaminase (5’DA), on the 5’-nucleotides content in the extracts, was evaluated. It was proved that in the spent brewery yeast there was a lysis of nucleic acids into 5’-nucleotides and deamination of the majority of 5’-AMPs into 5’-IMPs. By ultrasonic disintegration, the production of 5’-nucleotides could be increased with a parallel decrease in the level of hypoxanthine. A complex of lytical enzymes favours the production of 5’-GMP and 5’-IMP during a directed autolysis of spent brewery yeast. As a result of the use of Lyticase preparation, a 2.5 times increase in the
Key words: spent brewery yeast, flavour enhancers, yeast extract, 5’-nucleotides, waste utilization.