HOW LOW CAN YOU GO?

Rich Joy
May 14
4 min read

Some time ago (in the before times) the Brewing and Malting Barley Research Institute (BMBRI), developed a list of ‘Desirable Traits for Breeding & Research’ (https://bmbri.ca/research/desirable-traits-for-research-breeding/). This list was specifically made to ensure that breeders understood the needs, wants and desires of the malting, brewing and distilling industries. As such, a rolling hit list is regularly updated to reflect the ever-changing needs of end users. In this post I am doing a surface CIP on where we were and are with the topic of the enzyme wish lists.

North American malting barley is unique in that it has the highest enzyme potential compared to our cousins in the UK, Europe and Australia. The 2 row malting varieties bred and grown in NA average ‘roughly’ 25% higher in enzymatic activity for Pilsen, 2 row and pale malts compared to the UK, Europe and Australia. This number can get much wider as the protein increases, however, another topic for another day. This trend is highly desirable to adjunct brewers and NA, bourbon-style distillers.

Looking back, there was an increasing push for malt barley breeders to decrease the level of enzymes (specifically referencing diastase and alpha amylase; https://www.asbcnet.org/Methods/MaltMethods/Pages/default.aspx; Malt-6, Malt-7), free amino nitrogen (FAN), total protein and Kohlbach Index, (https://www.brewersassociation.org/educational-publications/malting-barley-characteristics/ ). This was especially evident as the craft industry started to take hold in popularity and volumes. There was a need for less enzymes for craft brewers, for those brewers using single infusion mashes (https://beersmith.com/blog/2008/11/28/infusion-mashing-and-decoction-for-brewing-beer/) which relies on temperature ramping in the mash tun. Single infusion mash profiles usually have several steps including an acid and glucanase rest, a protein rest and a saccharification step whereby the brewer ramps up to the appropriate temperature and then holds for a predetermined time. The lower the enzymatic power, the better control over conversion, hence better control of sensory characteristics, mouthfeel, organoleptics, ….. At the time that this white paper was published (2014), most Canadian varieties (AC Metcalfe, CDC Kendall, CDC Kindersley, AAC Synergy,………..) were high enzyme and excellent for adjunct brewing and for high through-put production brewers. The issue with these varieties from a craft brewing standpoint was that the malt screamed by the carbohydrate and protein rests leaving the brewer with few options to develop unique beer profiles.

The only potential low enzyme variety at the time was CDC Copeland (released around 1999) but the continued communication from the craft sector and the Brewers Association (BA; https://www.brewersassociation.org/ ) was we need it lower.

Fast forward to 2025 and we are still looking for the unicorn variety with ultra-low enzymes (from a NA-bred perspective). The current contenders out of Canadian breeding programs still baseline with Copeland at a low protein point so the questions that need to be asked are:

1) What is the artificial target? (120, 110, 100, 90 °L?)

2) How low is too low?

There are multiple complications when we consider this topic and hitting the desirable mark. First that comes to mind is that all barley processors (maltsters) produce different results with the same variety. Different location, different style of malt house, different processing regimes,…….. Further to this, testing, although industry standardized, still varies from lab to lab. Next, where the variety is grown is a large factor when considering geographical differences and soil-types. And then there are the growing season and climactic changes. Even if a variety has the propensity to lower protein levels, if the growing season is hot and dry the variety will produce higher protein levels and subsequently higher enzyme levels.

So, are we hitting our heads on a brick wall and should default to the easy button (elephant in the room)? That would be importing and/or growing UK, European & Australian varieties in NA? It has and is being done to varied successes (Hot Potato Alert! breeders rights (PBR), regulatory compliance, trade agreements and tariffs, seed certification laws, licensing and usage agreements, ….). For example, the variety ‘Odyssey’ is being grown in the USA and being used for both brewing and to a limited extent, distilling. This UK variety grows reasonably well; however, it does succumb to some extent to elevated protein levels compared to its home habitat (possibly due to dryland climate vs. Mediterranean climate?). OR should we continue to push the breeding windows with our global elite breeders in north America. The answer is likely a combination of the options for the time being. One last comment on varieties – AB Dram may be a contender at the craft level? More to come.

Our community needs to come together and have another look at this interesting topic, and I am sure that end users (brewers) have a few opinions on what works and what doesn’t (what are some looking for and what is ‘good enough’?). I suspect that the answer is as different as there are different brewers? As always, there are more questions than answers but let’s look at where we should go with this and move on to other traits to work on. For breeders it’s a numbers game and for the end users the focus is on ROI, and, and, and,…….

As usual – more questions than answers and we are opening the can again!