© 2020, Randy Mosher / Craft Beer & Brewing Magazine
In the last few years, a cluster of new beer styles has been creating a lot of excitement: sour IPAs and/or milkshake IPAs. They really are quite unlike anything we’ve seen before.
We tried to find a shorter title, but it took a ton of words to capture the vibe of this bunch of beers. Typically built atop the hazy/creamy base of the “Northeast”-style IPAs (NEIPA), there are two main forks: sour IPA and milkshake IPA, although many have characteristics of both. They almost always include fruit, although some of the milkshake beers may be based on spices and other ingredients. Both typically include some noticeable hop aroma.
The sour IPAs are typically quick-soured by a lactic fermentation in the kettle. Breweries specializing in these sometimes get cleaner results in a dedicated fermenter. Fruit itself adds acidity, which amplifies the fruitiness.
Milkshake IPAs may have some sourness if they’re fruit-based (most are), but aren’t always purposefully soured. The milkshake name refers to the addition of lactose, an unfermentable milk sugar, plus an overall presentation That’s creamy, sweet and rich, with vanilla often added to reinforce those qualities.
So, that gives us sweet, sour, creamy and bitter in our mouths, along with additional flavors from fruits and spices. Each sip is a smack in the kisser, which is what enthusiasts like about them. But with so many flavors vying for attention, making a harmonious whole can be tricky, compounded by the fact that bitter and sour can sometimes clash. And because these beers veer strongly into the direction of food flavors, bitterness can feel a bit alien since it’s usually absent in that context.
It’s worth asking: “Are these really IPAS?” If you’re a style classicist, then these depraved mutations will be a final indignity for your long-suffering favorite. If you’re new-school enthusiast of these brilliantly futuristic variations on a theme, you’ll find plenty in these beers to connect them back to the IPA branch of the beer evolutionary tree. So, it’s a divisive topic. In my view, they are just barely IPAs, but styles, as with any kind of language, means what people think they mean, so, yes, they’re IPAs.
Alcohol follows the IPA style: roughly between 6 and 8 percent by volume, although stronger versions are possible.
Malt is a minor player in both styles, but like the NEIPAs from which they’re derived, it’s not the star. Pilsner malt is the base, perhaps with a little pale ale or light caramelly malt (caramel 10 or Vienna) for a little additional richness. Unmalted wheat, rye or oats add a palate-filling creaminess that’s especially important in the milkshake variant. The beers are either pale or tinted with the fruit. Hibiscus or other additional ingredients are sometimes used to deepen the color.
Kettle souring brings lactic acid, which has a perceptible sour cream aroma and a certain softness–very different from the sharp citric and/or malic acids generally found in fruit. Also, a ketone called acetoin may bring a yogurty, dairy note. Under certain conditions, however, acetic acid bacteria can also produce some mercaptan off-flavor notes of garbage truck or old sewer pipe, which, when perceptible, besmirch the creamy/fruity delights of this style.
Hops, when evident, tend to be fruity. In fact, these styles really wouldn’t be possible without modern hops bringing pineapple, pear, apricot, mango, berry, white grape, melon and more. Hops must be chosen carefully to enhance or add depth to the actual fruit. Old-school hops like Cascade, with their pungent floral and piney notes, aren’t a great fit here.
With the majority of hops added either at the end of the boil (whirlpool) or in dry-hopping, it’s just about impossible to calculate bitterness. And because of the many different hop compounds from those processes can add bitterness, measurement doesn’t correspond to how bitter these beers actually taste. What’s more, acidity and sweetness can counterbalance or mask bitterness to some extent. If you have a trained palate, these beers might feel like they’re from 25 to 45 IBU, the entire span of the “moderate” range.
Like the NEIPAs from which they sprung, these beers are usually double dry-hopped: once during active fermentation and again a few days later when fermentation is done. The first allows the yeast to “biotransform” a few of the hop aroma chemicals, changing them from floral to more desirable citrus and lemony notes. The first dry hopping also creates the permanent haze. But no matter how cloudy, these beers shouldn’t have more than a trace of yeast, as having dead creatures in your beer will come to no good as they decompose.
With a few exceptions, both styles revolve around fruit. These are not simple summer fruit beers, but in-your-face fruit forward. This requires a lot of fruit, typically in the form of aeseptic or frozen purée. Natural fruit extracts are sometimes used as well, but they’re best employed to restore some aroma that may get lost during fermentation. Used alone, that can seem one-dimensional or candy-like. Fruit extracts are formulated to create a particular flavor depending on their intended use, and don’t always taste like fresh fruit.
The perception of fruit in a beer depends on other things besides aroma. Mouthfeel, sweetness and most importantly, acidity–both the amount and the kind– help create the full fruit experience. Eating a strawberry, for example, gives us 100% strawberry in our mouth, our flavor standard for what strawberry should be. So, a beer brewed with 10% strawberry, which is a sizable (and expensive) amount, we have only 10% of the appropriate acidity. The aroma tells us we’re drinking strawberry, but our mouth is not convinced. While the majority of these beers use a lactic souring, other acids can be used: citric, malic, succinic and tartaric acids each have their own character and can be matched to the fruit in the beer, as each fruit naturally contains a certain mix of acid types. Color may seem to be a superficial cosmetic, but it strongly affects the way we perceive fruit flavors–even, it has been shown, with trained professionals. So a nice vibrant color to match the fruit is essential.
Beers can be brewed sweet or dry tasting by manipulating the mash temperature and other variables, but there is a limit to how much residual sweetness can be achieved by this. For more sweetness, lactose is often added to these beers. Tasted by itself, it has a dull and unsatisfying sweetness, but in the context of these beers, it can definitely pop the fruit and even add to the perceived richness overall.
Vanilla can work similar magic. While it by itself vanilla is not sweet, our collective experience is invariably linked to sweet foods. When we smell it, our brain fills in the gaps and adds some of that sweetness we’ve learned to expect, so vanilla, even when very subtle, makes anything taste richer, rounder and sweeter.
Those childhood olfactory memories can be more specific, with the right combination of fruits, spices and other flavors conjuring up ice cream, pastry or some favorite childhood candy. And as you have probably have experienced, olfactory memories come loaded with emotion, and they’re usually positive when we’re talking about comfort food. It’s little wonder that brewers are brewing beers that tickle our memories of PB&J, fruity desserts, Pop Tarts and any number of nostalgic favorites.
We must talk about balance. With hops, malt, wheat, acid fermentations, sweetness, spice and more, there are a lot of working parts here. The challenge is to get them all singing together and not sitting uncomfortably in the same glass of beer or even fighting. Acid and fruit love each other; bitterness can make the whole affair an awkward threesome. Brewers making NEIPAs often skip the kettle hops or reduce them to almost nothing, and that is especially critical here.
Spices and other seasonings are very sensitive to the quantities employed. My personal preference is to use them to create a strong overall impression, then let the drinker peel away the layers, sip-by-sip.
There is a bit of a conundrum regarding drinkability. As a brewery, we love to have people drink our beers, and we hope to make beers that taste as good in the final sip as the first. However, given the rules of the Internet where these beers live or die, the preference is for punchy flavors that satisfy on the first sip–the wow factor. You can do both, of course, but as with everything else about these beers, it’s tricky.
Watching a style develop and mature is a thrilling thing, and this style offers a great vantage point to watch the happen. Just pop open a can, put your feet up and taste as the future unfolds.