According to a fellow who’s an expert on search engine optimization, one of the most googled lines related to beer is “what’s the difference between ale and lager”.

It’s a question I’ve been asked many times in my beer-writing life. Usually, depending on the attention span of the questioner, the answer is along the lines of “something, esters, something temperature, something, sulphur, something top-fermenting, something bottom-fermenting, blah, blah, German caves, industrialization …” and so on and so forth until one of us has fallen has asleep.

The truly long answer featuring hundreds of years of tradition and intimate discussion of genetics could take all day. (Like did you know that lager strains as used today are a hybrid of ale yeast and a wild yeast from Patagonia that apparently got to Germany by hitching a ride with a fruit fly?)

The long answers are so complex, it might be better to go with the shorter answer which could amount to: “There’s not that much difference in the yeast, but ingredients, process and marketing all come into it.”

Why am I even talking about this? Well Cold IPA — an India Pale Ale brewed with a lager yeast — has something to do with it as does the New Zealand Pilsner style which is often fermented with ale yeast.

I was once adamant there was a huge difference between lager and ale … and once when visiting DB Breweries in Otahuhu I quizzed legendary brewer Doug Banks about how they could make Tui with lager yeast and call it East India Pale Ale.

Doug had a long explanation but what I took from it was a line that went something like: “The yeast doesn’t know what it’s called.”

A quick, broad-spectrum, recap: ale yeasts typically refer to those which ferment best at warmer temperatures (18C to 21C is typical, and if you go higher there lie off-flavours and fusel alcohols). Lager yeasts like it colder (10C to 12C) but can go warmer. In the olden days, ale yeasts were known as top-fermenting in that the yeast, once it was done, went to the top of the fermenter. Lager yeasts are bottom-fermenting, i.e. they fall to the bottom of a fermenter.

Ale yeasts tend to create more fruity esters, but not always as there are now many “clean” strains. Lager yeasts often create a sulphur profile.

And here we are talking pure differences, we’re not even getting near speciality Belgian and German yeasts, wild yeasts, or Brettanomyces.

ENTER COLD IPA — Brewed with Lager Yeast

It’s accepted that Wayfinder Brewery in the United States were the first to coin the term Cold IPA for their IPA brewed with lager yeast and the addition of maize to lighten the body. The beer ferments at 18C, colder than a normal ale ferment, but high for a lager!

But it could be argued that Kelly Ryan, of Boneface, was doing much the same when he brewed at Fork & Brewer and created IPAs brewed with a type of lager yeast as far back as 2014.

“At Fork & Brewer I used lager strain, the Anchor strain, or California Common.”

For those not well-versed in the history of Anchor, the TLDR is they used a lager yeast but fermented it warm and called the resulting product Steam Beer.

“There was actually a story about it in Pursuit of Hoppiness back around 2015, and I remember people coming into Fork & Brewer and saying ‘I’ve heard you’re using a lager yeast to produce your IPAs’.

“That was really quite a shocking thing in New Zealand brewing industry back then.

“As much as I’m a stickler for the traditional in some ways, for me, I find hoppy beer presented better and cleaner when I used this warm=fermenting lager yeast.”

Ryan even won the Champion Pale Ale at the New Zealand Beer Awards in 2015 with Godzone Beat, a pale ale made with that same lager strain.

And while he was rule-bending in one direction, “I knew there were new kids on the block that later became quite big who were using a neutral American ale strain to get a quick pilsner to meet production pressures.”

BREAKING RANKS — Pilsner brewed with Ale Yeast

One of those beloved craft brewers breaking ranks was Joe Wood of Liberty Brewing.

He has been at the cutting edge of the New Zealand Pilsner style with his multi-award-winning Halo Pilsner, which according to style purists should not be called a pilsner at all because it’s brewed with an ale yeast – like many other New Zealand-style pilsners.

Wood went with an ale yeast because he wanted to dry-hop at around 18C rather than 12C during active fermentation in order to get the much-desired biotransformation of hops where they express more of that tropical fruit character.

Myth of lager vs ale

“With a lager yeast you don’t get a massive amount of biotransformation,” Wood says. “Riwaka and Nelson Sauvin are quite grassy normally, but with an ale fermentation, you can get those passionfruit characters out of them. So, it’s just down to the flavours I wanted to get out of those hops.”

Does he worry someone might critique him for making a pilsner with an ale yeast?

“I don’t care. They can say what they want, I’ve won trophies with that beer.”

Could he have used a lager yeast and fermented it warm?

“That depends on the yeast strain. More often than not you’re going to get hangover material — hot alcohols, and general off-flavours. Lager yeasts don’t attenuate out as much either, so if you want a crisp, dry finish like Halo has, you have to change the way you mash it, to get that residual sugar out.”

There’s also the time frame to consider: an ale yeast will ensure a brew is done and dusted, from sack to pack, in two weeks. That is critical at the height of summer.

“With Halo we brew Tuesday-Wednesday and we’re filtering 12 days later and packaging it Tuesday-Wednesday. You get better efficiency out of your equipment and it’s fresh and people love it.”


The original disrupter in the ale-lager binary system was Baltic Porter, an attempt by brewers in Baltic states to replicate the imperial stouts that were exported from Britain but then subject to a blockade by Napoleon.

The brewers in those colder climates found better success with lager yeasts as opposed to warmer-fermenting ale yeasts so adopted what worked.

Sawmill in Matakana make a perennially popular Baltic Porter and while they could easily expedite the process with an ale yeast, they stick to the style book and use a lager yeast, says founder Mike Sutherland.

Myth of lager vs ale

“We make quite a lot of beer using lager yeasts, which is not altogether that popular these days.

“We’ve made some beers with both ale and lager yeasts, and I think you just get a softer, more delicate profile with a lager yeast.

“The Doctor [a dark lager] is another example where we use a lager yeast, and you get a softness with that beer that you can’t replicate with ale yeast.”

And because he’s a “traditionalist” Sutherland sticks with the lager yeast for the Sawmill Pilsner and feels he gets the same hop aroma and flavour as he’d get if he brewed it with an ale yeast.

While many will look to North End’s Kieran Haslett-Moore as a style counsellor, he happily admits to being a heretic of sorts.

He brews North End’s NZ Pilsner with an ale yeast in summer, for efficiency, and a lager yeast in winter, when he has more time and is using other lager strains in the brewery. Despite having one of the best palates in the country he reckons he’d struggle to tell them apart.

“I know there’s a difference between the Pilsner batches in terms of how long it takes and what we do, but I don’t think I can taste the difference between them,” Haslett-Moore says.


Myth of lager vs ale
Kieran Haslett-Moore

Haslett-Moore also brings another dimension to a discussion, saying the genetics of the yeast are not as important as the equipment used.

“What we understand as lager and ale is an intersection of the genetics and the way we use them, because modern craft beer is inherently a fusion of ale brewing and lager brewing.

“Those words, lager and ale, describe a process as well a yeast.”

A traditional ale brewery would have wide, shallow fermenters, usually open at the top and the ale yeast would sit on the surface.

A lager brewery, in contrast, relies on tall conical fermenters where the yeast goes to the bottom.

Most modern brew kits are templated off lager (and larger) breweries, with tall, conical fermenters. Even if you use a top-fermenting ale yeast in such a fermenter the pressure and the shape of the vessel will force the yeast to the bottom. So, the idea of top- or bottom-fermenting yeasts are out the window.


Kelly Ryan at Boneface believes the outcome is the one thing that matters, as opposed to the yeast.

“If someone offers me a glass of beer, I’ll drink what’s in the glass and say whether it’s yum or yuck.

“What aim the brewer had or whether it was lager yeast or ale yeast doesn’t matter.

“But that’s not how it works in the world. When people see something on a shelf they want to connect with it in some shape or form and I think that’s where the name, marketing and style come into it for the 5 per cent of the New Zealand drinking public who are interested in such things,” he says with a laugh.

And Ryan knows first-hand that what’s written on the can has a huge bearing on whether it will sell.

Boneface have discontinued their multi-award-winning Outlaw India Pale Lager. It has been in the Top-30 at the New World Beer & Cider Awards and won a trophy at the New Zealand Beer Awards.

“In New Zealand, India Pale Lager doesn’t sell well as people are confused by the term ‘lager’, particularly the emerging beer drinker as they’ve decided they don’t like lagers, they like IPAs. And using the initials IPL means even less.

“We won champion international lager with Outlaw last year and we’ve done one batch since then and dropped it because it doesn’t sell.

“In contrast Cold IPA is a trendy name,” Ryan says, adding that he thinks it will have some stickability.

Boneface has brewed a couple of Cold IPAs, including The Wolf Bites Back, a booming triple IPA that brings bitterness and hop noise but finishes very dry.

Myth of lager vs ale

Without getting too technical on it, Ryan is of the view that Cold IPA and IPL are two different things, albeit the “differences are blurry”.

Most of the difference has to do with other ingredients as opposed to the yeast, such as brewing salts in the Cold IPA to increase the perception of bitterness and make the hops pop, and an adjunct such as flaked maize or dextrose, to lighten the body. In contrast an IPL has more residual sweetness and lower bitterness.

And this is where it comes back to process as much as the yeast strain, Ryan arguing that if all breweries had one yeast, the same 10 hops and a few salts, “you could do all sorts of things within those parameters”.

But he also acknowledges that yeast, is now the “great final frontier” in brewing.


After hundreds of years of being boxed into a set of constraints based on history — cool temperatures and certain styles — lager yeast (if not the style) is having a resurgence under these new “rules”.

Partly that’s due to the constant and quick evolution of beer styles in the past 20 years. As brewers innovate and create at a rapid pace, and beer becomes more popular, the brewing science is racing to keep up. Just as the past 20 years have been about hops —  oils, esters, thiols, terpenes, biotransformation — maybe the next 20 years will be about yeast.

“The bigger the industry grows, the more research is done,” says Ryan. “We’re learning more and speeding up and innovating.”

Ryan laughs when he thinks of the advances in the past 20 years.

“If you go back to 21 years ago when I was at Tui, it was very much in people’s minds that if a beer was a bit darker it must be an ale. Speight’s and Tui had a bit more colour than DB Draught or Lion Red so they were ales.”

Now it doesn’t matter what yeast is used, nor how it is brewed, and to a large extent, style conventions have become as meaningless as using colour to determine if something is an ale or a lager.

Basically, it’s what the brewer decides it is. And as many people cited in this article state: as long as it tastes good it doesn’t matter.