Identification and differentiation of brewing yeasts using specific and RAPD polymerase chain reaction

Specific polymerase chain reaction (PCR), using oligonucleotide primers that target the intervening region between the 5s and 16s rRNA genes, was used to differentiate commercially important brewing Saccharomyces cerevisiae variants from other yeast. In addition, random amplified polymorphic DNA (RAPD)-PCR with short oligonucleotide primers was used to identify yeast variants within S. cerevisiae. The fingerprint patterns that were generated by the RAPD-PCR technique could also be used to differentiate between brewing and non-brewing yeast. It was observed using this technique and the respective primers that ale yeast DNA was a better target for primer annealing than was lager yeast DNA.