Much of what we enjoy about beer today stems from innovative brewers’ hard work: creating novel brews, reinvigorating old styles (IPAs), or merging two styles into something greater than the sum of its parts. Done well, we’re often left questioning why nobody had thought of that before?
Cold fermented, well-hopped beers are not new, with India Pale or “hoppy” lagers the most recent styles. In most cases, a clean, well-brewed, lager-yeast fermented base beer with high levels of whirlpool and/or cold-side hop additions could pass for an American Pilsner, an India Pale Lager (IPL), or even a Hoppy Steam Ale.
But semantics aside, these crisp, hop-centric beers create a bridge between East and West Coast IPA styles. Clean, assertive bitterness, light-bodied dryness, and hop-forward balance between the dank C-hop characters of classic American IPAs, and the juicy fruit-forwardness of New England IPAs.
Let’s unpack some of the key strategies and techniques for brewing Cold IPA.
Quality grains, adjuncts optional
With Cold IPA, the malt forms a scaffold, a platform from which brewers display hop characters. Striking a balance between a crisp, well-attenuated body and just enough malt-cushion to counterbalance the aggressive hopping requires quality lager base malt, perhaps a touch of Vienna or Munich to hint at some of the bready, toasted characters. 5-10% adjuncts like rice and maize are also common, imparting subtle American-Lager like flavours and dryness.
We suggest Gladfield Pilsner, Organic Pilsner or German Pilsner Malt up to 100%, 8-10% Malted Maize, and a touch of Munich (3-6%) or Vienna to provide added depth to the malt, without becoming excessive.
Astringency is a common flaw in lagers. Their dry finish, lack of body and sweetness accentuates any powdery, tannic or tea-like palate sensations. Our previous PoH article on Lagers and Pilsners has tips on reducing astringency; the same rules apply here.
Dip Hopping
In 2012, Japanese beer giant Kirin employed a technique to remove myrcene, a hop oil associated with grassy, oniony, garlic-like flavours. US Brewers were soon experimenting with this process of steeping hops in hot water in the fermenter, using the heat and pressure to drive off myrcene, unlocking novel hop flavours and aromas for infusion into their wort. The process became known as “dip hopping”.
Hops are combined with 770C water in a closed fermenter and steeped for up to 1 hour, with periodic venting of pressure buildup. Once the steep is complete, fresh wort is pumped in from underneath at a higher gravity (accounting for dilution). The hop tea can also be removed and blended with fermenting wort.
Removing myrcene allows brewers to experiment with previously unsuitable, high myrcene content hop varietals.
Aside from dip-hopping, most strategies for making a great IPA apply to Cold IPAs:
- Use the freshest hops you can. No old open/ part bags, please.
- New products like Cryo-hops, Hop Oils, and AB Vickers Aromazyme (β-glucosidase biotransformation) can add additional intensity and complexity.
- Staged dry hop additions with earlier additions (day 1-3) for NEIPA-like juiciness; later (day 5-7) for a more traditional resinous, piney, or dank profile. The final hop addition(s) should ideally be added before the end of fermentation to prevent issues with diacetyl (dry-hop creep).
- Total Dry Hop Addition rates of ~6 to 16grams per litre. These approximate limits help prevent potential harsh bitterness or “hop burn.”
Pick a lager yeast, pick an ale yeast
The yeast used for this style is critical. We want to achieve a clean, crisp character that allows the hops to shine. Both ale and lager yeasts can be used. The key is to control the temperature with both types to limit undesirable flavour and aroma production.
As an IPA at heart, an ale yeast is an obvious choice. Ale strains such as LalBrew Nottingham™ or LalBrew BRY-97™ that are tolerant of cooler ferment temperatures are well suited. For Cold IPA, a temperature range of 15-18˚C is a good starting point. It should be noted that at these temperatures, the pitching rate should be increased to 0.8-1.0g/L (16˚P wort). The higher levels of biotransformation enzymes in LalBrew BRY-97™ assist in increasing the complexity of the finished beer.
An alternative would be to use a traditional lager yeast at warmer temperatures. LalBrew Diamond™ is suited for fermentation temperatures of 10-15˚C, although it can be pushed to 17˚C later in fermentation. A 1.4g/L pitch rate should be used at 15˚C (16˚P wort) to ensure vigorous fermentation and to control H2S formation, characteristic of lager yeast.
The jury may still out whether you’re brewing a Cold IPA, an IPL, a New World Steam Ale etc.? With quality base malts, appropriate yeast and fermentation control, and fresh hops used in novel ways, a beer by any other name would still smell (and taste) as sweet.