Introducing ModiGen™D Series Yeast Strains

ModiGen^™D: Yeast,engineered to be smarter.

Throughout the last year, White Labs and The Yeast Bay worked together to design, build, and validate a new set of bioengineered yeast strains. We set out to engineer our most popular yeast cultures to eliminate one of the most notable off-flavors in brewing: diacetyl. Considered an off-flavor in practically every modern style of beer, diacetyl can take considerable time to clean up naturally. This extended “rest” period is valuable time that eats into cold-side productivity, increasing tank residency time and lowering fermentation throughput.

These new ModiGen^™D yeast strains are genetically enhanced to express integrated a-acetolactate decarboxylase (ALDC). Unlike adding soluble ALDC enzyme, ModiGen^™D technology prevents the a-acetolactate secretion that drives diacetyl formation. They are designed to make your fermentation process easier, faster, and higher throughput.

The ModiGen^™D difference.

While a-acetolactate is a precursor to diacetyl formation when secreted into fermenting beer, it’s also a critical precursor inside the cell for the synthesis of two amino acids. Excessive ALDC production inside the cell, above what is required to prevent α-acetolactate secretion, depletes the intracellular α-acetolactate levels to the point that cells cannot effectively produce valine or leucine on their own. Once cells no longer have access to a nutrient-rich media (i.e. during flocculation, harvesting and storage), the inability of cells to synthesize all amino acids dramatically affects cell health and the ability to reuse yeast. 

We found it only takes a certain level of ALDC gene integration inside the cell to achieve effective diacetyl prevention. A more classical, slower approach to integrating the ALDC gene into ModiGen™D strains yielded better control over the number of ALDC genes inserted into the yeast genome and, consequently, the amount of enzyme produced. By controlling the levels of ALDC produced, we’ve shown that these ModiGen™D strains can reliably prevent diacetyl production without significantly impacting yeast health or repitchability.

Strain validation.

ModiGen^™D strains have been put through their performance paces to ensure brewers are receiving the same high-quality yeast they’ve come to expect from White Labs:

• Test Fermentations – validates ModiGen^™D strains significantly prevent diacetyl formation as compared to parent strains (including in beers dry hopped at 2.2 lbs/bbl), while exhibiting similar fermentation kinetics and yeast character.

• Harvest and Reuse Assays – validates ModiGen^™D strains can be harvested, stored, and reused, maintaining consistent fermentation kinetics and diacetyl prevention.

• Serial Growth Assays – validates consistent diacetyl prevention even after 50 generations (cell divisions), ensuring that brewers can reliably reuse ModiGen^™D strains with consistent diacetyl reduction.

• PurePitch^® Next Generation Viability Assays – validates the viability of ModiGen^™D strains over time is comparable to parent strains.
  
  

ModiGen^™D technology is available in:

 Pre-order your yeast today for first deliveries in mid-March.