Tuesday 27 June 2023

Lallemand - Lalbrew NovaLager - Yeast Overview


2022 saw the release of LalBrew NovaLager from Lallemand Brewing - a hybrid lager yeast strain offering the benefits of a classic lager yeast without some of the drawbacks generally associated with using them.

LalBrew NovaLager is considered a bottom fermenting lager yeast strain with characteristics that are ideal for lager beer production. Such characteristics include fast fermentation times, high levels of attenuation and a broad fermentation temperature range.

The genomic composition of NovaLager is a hybrid combination of Saccharomyces Cerevisiae (75%) and Saccharomyces Eubayanus (25%), resulting in a genetically unique strain of Saccharomyces Pastorianus with a lager classification of Group III - NovaLager being the first commerical example of this classification.

Flavour Profile

When using Novalager, you can expect a clean flavour profile with some slight esters all across the recommended fermentation temperature range, as you can see from the wheel below - though you will get reduced ester production at the lower end of the recommended fermentation temperature range.

Image Copyright of Lallemand Brewing

The ester character from Novalager is considered to be a little different to what you get from other lager strains, giving it a unique flavour profile with slight hints of red apple and tropical fruit.

Reduced Diacetyl Production

NovaLager is a low diacetyl producer - as demonstrated in the graph below, it generates significantly lower levels of diacetyl compared to Nottingham (ale) and Diamond (lager) yeast varieties. Lower initial levels during fermentation mean there is less to be cleaned up by the yeast after fermentation has completed (ie. the conditioning period), meaning faster turn around times for batches brewed.

Image Copyright of Lallemand Brewing

No Hydrogen Sulfide Production

There is also some neat technology in Novalager that inhibits the production of hydrogen sulfide (H2S), a common draw back of classic yeast strains which often produce hydrogen sulfide as part of the fermentation process. The smell of hydrogen sulfide is often likened to rotten eggs, and part of the extended maturation time required for classic lager yeasts is to allow undesirable byproducts of fermentation such as hydrogen sulfide to be cleaned up by the yeast, though with some lager styles, small amounts of hydrogen sulfide are normal and expected as part of the flavour profile.

As you can see in the graph below, hydrogen sulfide is not generated by the yeast at any point during active fermentation - no doubt a welcome change for anyone who has had their garage or fermentation area reeking of rotten eggs during a lager fermentation!

Image Copyright of Lallemand Brewing

Hop Biotransformation Properties

NovaLager is said to promote hop biotransformation and accentuate hop flavour and aroma, making it ideal for beer styles other than a classic lager. Think more hop forward styles like the Cold IPA, India Pale Lager (IPL), or other more heavily hopped lagers. Classic lager yeasts aren't known for their hop biotransformation properties so this is certainly something that will set Novalager apart from other lager yeast strains.

Attenuation Rate & Flocculation

Attenuation rate is quoted at 78 - 84%, and you can expect medium levels of flocculation along with it. If super clear beer is a priority then you may need to look at adding fining agents to help your beer drop clear since the flocculation level is a little lower than typical lager yeasts like the Diamond variety which has a high level of flocculation.

Temperature Range

The recommended temperature range is 10-20°C (50-68°F) giving a reasonably achievable target range for homebrewers that's pushing up into ale yeast territory. Fermenting at the lower end of this range will lead to a longer fermentation time and lower ester production, and conversely, fermenting at the higher end of this range will lead to a shorter fermentation time and increased ester character.

Alcohol Tolerance

Reasonably high levels of ABV can also be achieved with an alcohol tolerance of up to 13% ABV. Another benefit of the ale component of this hybrid strain is this higher alcohol tolerance compared to other traditional lager yeasts.

Pitching Rate

The recommended pitch rate for Novalager is 50-100g/hL meaning a single 11g pack is sufficient for a typical 20-22L batch, and is more in line with an ale yeast pitching rate since typical lager yeast pitching rates are around 100-200 g/hL. For higher gravity worts, pitching at the higher end of this range would be advisable.

The below graph taken from the Lallemand website gives a visual representation of the fermentation time of the NovaLager yeast strain compared to two of their other popular strains - LalBrew Diamond and LalBrew Nottingham. 

Image Copyright of Lallemand Brewing

You can see that NovaLager reaches it's terminal gravity faster than the other two yeast strains, and also has a lower finishing gravity.

Conditioning Time

The conditioning time when using Novalager is significantly shorter than when using traditional lager yeast strains. Conditioning is the period after primary fermentation where the yeast will continue to work away and "clean up" some of the undesirable byproducts of fermentation. Since Novalager produces some of these byproducts in reduced amounts (like Diacetyl), or not at all in the case of hydrogen sulfide, there is less for the yeast to do and the beer is conditioned and ready for consumption sooner. The primary reason for any conditioning time after primary fermentation with Novalager is to help improve the clarity of the finished beer.

Beer Styles

Novalager is suitable for use in a broad range of beer styles - anything that would call for a fairly neutral flavour profile will be a good candidate to use this yeast variety for. We've previously mentioned Cold IPA and IPL, but just about any classic lager will turn out well, especially those with a little more hop character.

Looking at the flip side of this equation - what beer styles aren't suitable for creating with Novalager, and this would simply be any lager style that requires and expects some degree of hydrogen sulfide to be present, since Novalager doesn't produce this at all. It's also not a particularly good alternative to some ale yeasts that produce enhanced ester characters like some english ale yeast varieties for example.

Pressure Fermenting

There isn't a great deal of official information as to whether or not Novalager is a suitable candidate for pressure fermenting. We suspect that the yeast itself would handle pressure fermenting without too any problems, but the question you would need to ask yourself is, why use it under pressure? 

Pressure fermenting will only further suppress the limited ester character you will get from the yeast under normal fermentation conditions, and given the relatively high temperature range you can ferment at, there doesn't appear to be a great deal of benefit to be had from fermenting under pressure. Sure, you could probably do it and get a really clean and neutral flavour profile, even above the recommended maximum of 20°C, but we'd recommend fermenting normally for the first few days (when most of the esters and flavour compounds are produced), and then fit a spunding valve toward the tail end of fermentation to get a head start on force carbonation.

Summary & Final Thoughts

So, what's the big deal with Novalager yeast? It's an exciting development as new yeast varieties like this aren't released very often. Essentially, Novalager has been developed and targeted to homebrewers and commercial brewers alike as an alternative to the typical lager yeasts that have been in use for decades or even centuries. It provides a more robust and temperature tolerant lager yeast that produces reduced diacetyl levels and no hydrogen sulfide at all during fermentation. This means that clean, neutral lagers can be created faster, which is particularly ideal for commercial brewers who no longer have to give up valuable tank space for a beer to lager or condition for weeks on end.

With enhanced biotransformation properties, NovaLager would be more suited to modern, hop forward styles that don't necessarily work well with traditional lager yeast varieties - something that consumers and homebrewers are crying out for more of in recent times.

We're very much looking forward to trying this yeast for ourselves in the very near future and will of course share our results and findings.

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