Your Needs Change, Your Yeast Can't

The Xcelis Yeasts platform from IFF offers tailor-fit yeast and yeast blends to address ethanol producer needs—even as they vary over time.
By IFF | December 20, 2021

Over the past year, ethanol producers have used Synerxia® Ruby, Synerxia Sapphire, Synerxia Emerald, and eBoost® GTX yeasts to increase ethanol yield, reduce residual starch, improve operational consistency and enhance fermentation rates. Now, blends of these yeasts are enabling even greater fermentation performance. 

“We have found that yeast blends are very often greater than the sum of their parts,” says Lee Robinson, IFF lead application scientist. For example, during a heat-stressed fermentation, performance for a blend of 50% Synerxia Sapphire and 50% eBoost GTX is significantly more robust than eBoost GTX alone and delivers a higher ethanol yield. The resiliency of Synerxia Sapphire really shines because it consumes glucose that the higher yielding but less robust eBoost GTX would otherwise leave behind.

Synerxia Sapphire makes yeast blends significantly more tolerant to stressors such as heat, high ethanol titer, and infections, while eBoost GTX provides dramatically enhanced ethanol yield and ultra-low glycerol production.

Another benefit of the platform is flexibility. Your process and market conditions change over time, so shouldn’t your yeast solution adapt? At times, you may need more plant throughput, which can be enabled by a high-rate yeast. At other times, such as when a severe infection is experienced, an ultra-robust blend may be required. Perhaps you have invested time and money into providing the most ideal fermentation conditions and want to run the highest yielding (but less robust) yeast solution. The Xcelis® Yeasts platform allows an ethanol producer to seamlessly switch the yeast blend to meet the needs of the moment.

So how does the ethanol producer determine the right yeast blend? The concept of yeast blending can be overwhelming. How will the two yeasts perform during fermentation? What is the right ratio of yeasts? Fortunately, IFF has been modeling and testing yeast blends for the past two years to answer those very questions.

Zach Baer, who leads new model development for the Xcelis® AI fermentation modeling group, is pioneering models that mathematically describe single yeasts and yeast blends. “We have learned some very interesting things,” Baer says. “We originally thought that two yeasts in a blend would perform as the average between the two yeasts. What we actually found is that there are strong positive synergies between IFF yeasts. We can blend a fast, robust yeast with a high-yield yeast, and we find that both yield and robustness are greater than predicted.” To help producers decide between many potential blends, our Xcelis AI fermentation models allow for efficient, virtual comparison of blend options in plant-specific conditions.

Josh Naylor, IFF marketing coordinator, adds that IFF is laser-focused on providing the best fermentation results for its customers. “This isn’t about products—this is about customer outcomes,” he says, adding that yeast blends should provide the highest yield possible given the customer’s process conditions, and be flexible enough to change with market and process conditions over time.

IFF customers have demonstrated that they can significantly enhance fermentation performance through yeast blending. We are excited to bring value-added yeast blends to the fuel ethanol industry.