Better control of fermentation - FAN and diacetyl

Better control of fermentation - FAN and diacetyl

Challenges for brewers with FAN and diacetyl

For optimal fermentation and beer quality, yeast needs sufficient Free Amino Nitrogen (FAN) to grow. This translates into acceptable beer quality.
Diacetyl causes a butterscoth or buttery flavor in beer, and it is often ranked as one of the most offensive off-flavors in Pilsner-type beer. Yeast produces extra diacetyl as a result of stress, which can be due to low FAN.

Consistent FAN levels and stable fermentation

With Novozymes enzymes, brewers gain consistent, higher levels of FAN and stable fermentation even in high-barley or high-adjunct brewing. Brewers also gain improved mash filtration and extract yields in the brewhouse – without compromising on beer foam stability – due to the changes the enzymes make in the protein matrix.

Reduce diacetyl and costs

Diacetyl is a key maturation indicator. Novozymes enzymes offer a reliable and predictable process that prevents the formation of diacetyl during fermentation, without influencing the flavor profile of the final beer.

With Novozymes enzymes, brewers can effectively control formation of diacetyl, which reduces cellar costs, maturation times and the need to reprocess batches due to high diacetyl.

A family of solutions

Fermentation control is just one of the many solutions that Novozymes offers for brewing.

Breweries can use enzymes to optimize the use of raw materials, improve wort separation and beer filtration, to maximize attenuation of high strength and light beers, gain flexibility in adjuncts.

Your solutions for FAN and diacetyl control

To increase FAN, Novozymes offers Neutrase® 0.8 L, BrewQ® and FAN Boost™. These products provide predictable, consistent, higher levels of FAN when the brewer requires it, based on malt modification and choice of raw materials. These proteases do not adversely affect beer foam stability. Modification of the protein matrix by these solutions can also have a positive impact on wort filtration and extract yields in the brewhouse


  • FAN control for improved yeast growth and stable fermentation
  • FAN optimisation in high barley/adjunct brewing
  • Improvement of mash filtration
  • Yield improvement

Novozymes Maturex® Pro is a unique enzyme specially designed for the brewing industry, making it possible to rethink fermentation profiles of pilsner type beer, or any beer where diacetyl flavor is unwanted. Maturex® has been used for many years for quality and cost savings.


  • No diacetyl off-flavors
  • Shorten, or even by-pass rate-limiting warm maturation (diacetyl rest)
  • Optimise vessel usage
  • Increase beervolume - a reduction in fermentation means an increase in throughput
  • Maintain high quality index of finished beer
  • Increase "right first-time", less re-work
  • Reduce energy consumption

Questions about FAN or diacetyl?

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