Renaissance BioScience, a global bioengineering company, has developed a breeding platform for creating novel, non-GMO yeast hybrids for lager beer production. 

The new technology is positioned to dramatically broaden the diversity of commercial lager yeast strains worldwide and enable beer manufacturers to fine-tune and enhance proprietary strains.

For hundreds of years, lager beer has been produced using only strains from two related lager yeast types: Group I and Group II, according to the company. 

Although these groups are genetically different, they produce very similar flavor and aroma profiles and thus play a role in the lack of diversity in commercial lager beer.

“These novel hybrid strains are very versatile and robust in their capabilities,” Zachari Turgeon, principal scientist at Renaissance BioScience tells FoodIngredientsFirst.

With this novel approach, the company proposes the hybrid yeast fall under a third group of lager strains called Group III.

“The platform has significant potential to expand flavor profiles and improve the industrial efficiency of beermaking,” he adds. 

Renaissance BioScience CEO, Dr. John Husnik, comments: “This Renaissance achievement is one of the most practical innovations in lager yeast strain development. We’re about to enter a whole new world of lager beer innovation.”

An age-old problem
To date, approaches aimed at creating new lager yeast have generated strains that possess undesirable brewing characteristics that render them commercially unviable, states the company.

The Renaissance approach was to breed the Saccharomyces eubayanus subgenome from industrial lager strains and hybridize them to different ale strains, eliminating the need to breed undomesticated, wild S. eubayanus strains.

This approach allows for the creation of new lager strains that are directly suitable for lager production. 

“The beauty of this approach is that you could technically use any yeast strain as the second parent, so you could make lager hybrids with different types of strains to target traits you are trying to combine with a lager yeast,” continues Turgeon.

A new lager strain
The Group III strains developed by Renaissance offer more versatility to manufacturers. They have a wider temperature tolerance range, for example. 

This can increase their uses for different styles of beer, as well as improve propagation and the manufacturing of the yeast.

The company is interested in exploring what sort of interesting traits it can use this technology to breed into lager strains, says Turgeon.

Some examples would be to significantly reduce the production of the off-aroma hydrogen sulfide (rotten eggs smell) as well as lower diacetyl levels during fermentation. 

“This could result in reduced conditioning time required for lager beer production, which would increase brewing capacity, especially for small craft brewers who do not have the capacity for lagering beer for extended periods of time.” 

It would enable faster tank turnover and increase beer output, both of which can help make beer production more cost-efficient. “Those are just a few examples of what can be done,” he details. 

Getting to market 
The yeast technology is ready to begin commercial usage and applications, according to Husnik. 

However, the company is cautious of predicting when a finished product will be available, as it is still in an early stage. 

“It looks very promising,” Jessica Swanson, lead development scientist and beverage unit manager of Renaissance BioScience, tells FoodIngredientsFirst.

“We have a manufacturing partner that holds the license for this technology. They currently have a few of these new Type III lager yeast in their fermentation lab and are carrying out assessments.”

In addition to developing a market-ready product, the company can also apply this breeding technology to existing industrial lager yeast for improving and diversifying lager characteristics.

What defines a lager 
Various brewing organizations have different guidelines for what defines lager beer. The 2020 Brewers Association’s beer style guidelines lay out 33 different variations of lager beer, including traditional styles such as the Pilsen-styles, and newer styles such as the tropical-style light lager.  

“All these beers have the same species of yeast in common: Saccharomyces pastorianus also known as lager yeast,” explains Swanson. 

“Scientists have discovered that it is the S. eubayanus subgenome of the lager yeast which infers its cold tolerance and sets it apart from its warmer fermenting counterpart, which is the ale yeast. So technically, if a yeast contains this S. eubayanus subgenome, we think of it as a ‘lager yeast.’” 

The term “lager” can also be used as a verb to describe the process of storing beer at cold temperatures during a period of aging. 

It’s this cold fermentation and aging that likely drove the selection of the S. pastorianus yeast as a defining lager ingredient, Swanson concludes.  

A paper detailing Renaissance BioScience’s development of the new approach was recently published in the journal of Applied and Environmental Microbiology.