GY7B: A New Yeast Species

Lead Inventor

Matthew J. Farber, PhD, Former Director, Brewing Science Certificate Program at Saint Joseph’s University

Associate Professor of Biology, Rowan University

Unmet Need

A new yeast species has been discovered at Saint Joseph’s University that is capable of fermenting a pleasant, aromatic sour beer. 

Typical sour beer production relies upon secondary fermentation with bacteria to develop a complex sour beer flavor profile which can take months or years to fully develop. 

Yeast stain GY7B is a novel, lactic-acid producing yeast capable of acidifying beer to pH3.5 (Titratable acidity as lactic acid ~6-8g/L) in as little as 5 days with final attenuation at 2-3 weeks. 

It is a highly attenuating strain (~95%) which yields beers with bright lactic acidity balanced by a slight sweetness and mouthfeel from glycerol produced during fermentation. Perfectly complementing the tartness of the beer is a pleasant bouquet of apple esters with no discernable off-flavors. 

GY7B performs well by itself or in co-fermentation with other ale yeast. High flocculation character yields a brilliantly clear beer without filtration. GY7B presents the opportunity to quickly brew a delightful sour beer without the limitations and risk of using bacteria.

GY7B Fermentation Stats

Intellectual Property

US Patent No. US 11,286,445, issued March 2022

US Patent No. US 12,054,696, issued August 2024

Also issued as AU2018304545 and BR1120200011762

Collaboration or Licensing Opportunity

Licensed to Lallemand Specialties Inc.

References and Publications

• DeMichele G. Farber M. GY7b: a novel species capable of bacteria-free sour beer production. Proceedings of the American Society of Brewing Chemists. World Brewing Congress (2020).