Pale, hoppy ales — especially American pale ales (APAs), American IPAs and double IPAs (dIPAs) — are a favorite of American homebrewers. They are all brewed in a similar manner, with the common thread of showcasing American hops. However, there are some differences, too, beyond the fact that they get bigger and hoppier as you progress from APA to IPA to dIPA. Knowing the similarities and differences will give you the confidence to formulate and brew your own pale, hoppy beer recipe.
Other Pale, Hoppy Beers
Of course, the English have a series of pale, hoppy beers, too. These range from ordinary bitter, best bitter, extra special bitter and on up to English IPA. And American pale beers have spun off or hybridized with other styles to form amber ales, rye pale ales, Belgian IPAs, rye IPAs, black IPAs, white IPAs, etc. However, for this series of articles, I’ll focus on “typical” American pale ales, IPAs and double IPAs.
It’s The Water
In recent years, many homebrewers have been paying more attention to their brewing liquor (water used to brew with). One thing brewers attempt to do is adjust the mineral content of their strike water (water used to mash in) such that their mash pH falls in a reasonable range (5.2–5.6). In addition, some ions are thought to accentuate various beer flavors. Specifically, water high in sulfate (SO42+) ions is thought to accentuate the hop character of a beer while water high in chloride (Cl–) favors the malty notes. In this article, I’ll discuss the most relevant water issues, with the exception of chloride and sulfate ions (which I’ll tackle in the next article.)
The Very Basics
If you use municipal tap water, all of the things that are very bad for beer production — iron (Fe2+, Fe3+), nitrates (NO3–), fecal coliform bacteria, etc. — should be far below the level they can cause any harm. Beyond selecting tap water that tastes good, one thing all brewers should do is eliminate any chlorine compounds from it. Most municipal water sources use chloramine as their source of chlorine and this can be eliminated by either a suitably large carbon filter (the under-the-sink type cartridge filters will do the job) or by treating up to 20 gallons (~80 L) of water with one Campden tablet. Crush the tablet and stir it into the water. The chloramines will be removed instantly, but you’ll want to let the water sit overnight before using it. Campden tablets release SO2, and you should let this gas diffuse out of your water to avoid faint sulfurous, rotten-egg aromas in your beer.
Extract brewers do not need to worry about mash pH. (For more on this, see my article on water treatment for extract brewers.) So, in most cases, any potable tap water that has been dechlorinated is suitable for extract brewing. And, in fact, if your hoppy ales have turned out well in the past, there’s no real need to go any farther in examining your water chemistry. If your hoppy beers have been lacking, however, you will need to get a local water report. In the US, these are free for the asking. You will use this to adjust your chloride to sulfate ratio (in the next article).
All-Grain Brewers: pH
In terms of mash pH, the mineral content of your brewing liquor for a hoppy American ale should be similar to the water you use to brew most other pale beers. The grist for all of these ales is generally 90–100% pale malt, with any remainder typically being light crystal or CaraPils malt. You will want the carbonates in your water to be low (under 50 ppm, and preferably below 25 ppm), because they inhibit the mash from falling into the correct pH range (5.2–5.6 acceptably, and ideally 5.2–5.4). The easiest way to reduce your carbonate levels is to dilute your tap water with distilled or RO water. It can also be reduced by the addition of acid.
[Edit: Carbonate can exist in a few forms in aqueous solutions. HCO3– is bicarbonate, the type of carbonate most prevalent in tap water given it’s usual pH range. Carbonic acid (H2CO3) and carbonate (CO32-) are the two other forms of carbonate. In this article, I use “carbonates” to mean any of the forms, with the assumption that it’s mostly bicarbonate in the relevant pH range.]
Conversely, you want the levels of calcium to be high enough because their reaction with phosphates from the malt lowers pH. (Magnesium also contributes to a drop in mash pH, but it’s effect is weaker than that of calcium.) When adjusting your calcium levels, gypsum (calcium sulfate, CaSO4) and calcium chloride (CaCl2) are the two most popular mineral salts.
Calcium in the ballpark of 50 ppm is usually sufficient for pale beers (SRM < 12) if your carbonates are low (under 25 ppm). However, in a pale beer with only 50 ppm of calcium in the strike water, another addition of about 50 ppm is recommended once boiling commences. This will ensure that a reasonable post-boil pH (5.0–5.2) is reached. Calcium also retards color pickup during the boil.
So, all-grain pale ales, IPAs and double IPAs all require basically the same water — low in carbonates, and with enough calcium to drive the mash pH below 5.6 (and ideally into the 5.2–5.4 range). For extract brewers, the only real requirement is that the water tastes good and has been dechlorinated. Tomorrow, I’ll discuss the role of chloride and sulfate ions in brewing a hoppy beer. I’ll also give a step by step guide to transforming any municipal tap water into suitable brewing liquor for an APA, IPA or dIPA.
This is Beer and Wine Journal’s second beer style series. Our first, dry stouts, was posted in June 2013.