Guinness Nitro Beer: What Are Those Ibus?

Guinness Nitro IPA is an English-style IPA with 44 IBUs. IBUs, or International Bitterness Units, are a measure of the bitterness of a beer, which comes from the hops used in brewing. The number of IBUs in a beer is determined by a chemical analysis of its iso-alpha acids, which are compounds found in hops.

The nitro beer has a creamy, smooth texture

The process of infusing beer with nitrogen gas was first developed and popularised by Guinness. This process subtly alters the beer's aroma and flavour while lending it a silky, creamy mouthfeel. The nitrogen forms smaller, more profuse bubbles than carbon dioxide, which gives the beer its smooth texture.

Nitro beers, such as Guinness, have a unique appearance with a gorgeous cascade of ultra-fine bubbles that settle into a creamy foam. The head of the beer persists for a long time, creating a pillowy hat of foam. The nitro beer has a smooth, creamy texture that makes it stand out from other beers.

The smoothness of the nitro beer also affects the flavour. The first thing you notice is the hops, which provide an earthy and floral balance to the malt backbone of the beer. The nitro leads to a creamy body that makes the beer exceptionally drinkable. It has a light mouthfeel and a clean, dry finish. The overall smoothness of the beer makes it a great choice for those who prefer a lighter and smoother drinking experience.

It has a low bitterness and hop aroma

The Guinness Nitro IPA is a low-bitterness beer with a surprisingly low amount of hop aroma for an IPA. The beer has 44 IBUs, which is relatively low, and this, combined with the low carbonation level, allows the malt aroma to be more prominent. The hops provide an earthy and floral balance to the malt backbone of the beer but are subdued for an IPA. The beer's blend of CO2 and nitrogen helps to balance out the profusion of hop flavours.

The nitro leads to a very creamy body, making the beer exceptionally drinkable. It hits the palate very lightly and finishes clean and dry on the tongue, despite the smooth and creamy texture. The overall impression is that the beer is lacking something as an IPA. The bitterness could be higher and still be lower than other IPAs. The smoothness makes the beer feel somewhat lifeless.

The Guinness Nitro IPA is an English-style IPA, not an aggressively hopped American IPA. The overall flatness of the beer under-accentuates the malt and hop character. The perceived bitterness is much less than the 44 IBUs indicated, due to the flatness. The beer has a creamy, pine-like character with a medium-sweet, toasted malt presence. There are also minty notes in the flavour, as well as white pepper and a twig-like woody character. The aftertaste is somewhat fruity, like fruit cocktail syrup.

It's Guinness' first attempt at an IPA

Guinness Nitro IPA is the brand's first attempt at an IPA, specifically an English-style IPA, which was released in September 2015 as a follow-up from The Brewers Project™.

The beer is brewed with Irish barley malt, a touch of roasted barley, and five hop varieties: Admiral, Celeia, Topaz, Challenger, and Cascade. The blend of CO2 and nitrogen helps to balance the profusion of hop flavors, creating the signature surge and settle of Guinness™ Draught. The IPA is brewed with the same unique Guinness yeast strain used to ferment all stouts at St. James's Gate in Dublin, Ireland, where the beer is made.

The beer has a surprisingly low amount of hop aroma for an IPA, likely due to its low carbonation level and relatively low 44 IBUs. The low hops allow the malt aroma to shine through more than is typical for hoppier IPAs. The beer pours with a cascade of ultra-fine bubbles that settle into a creamy foam, and the liquid settles into a clear amber color.

The flavor of the beer is earthy and floral, with a subdued hop presence for an IPA. The malt provides a light body with notes of cracker and toast. The nitro leads to a creamy body and a smooth, clean, and dry mouthfeel. Overall, the beer is very drinkable, but it may lack something as an IPA due to its low bitterness and smoothness.

It's an English-style IPA, not an American IPA

Guinness Nitro IPA is an English-style IPA, not an American IPA. This means that it has a much lower carbonation level and fewer IBUs (International Bitterness Units) than its American counterpart. In fact, with only 44 IBUs, the Guinness Nitro IPA is bordering on out-of-style for an IPA. However, the relatively low number of IBUs allows the malt aroma and backbone to shine through more than in hoppier versions of the style. The beer's blend of CO2 and nitrogen also helps to balance out the hop flavours.

The English-style IPA is characterised by a hearty helping of English hop character (earthy and floral) and increased alcohol content. English yeast lends a fruity character to the flavour and aroma, offering a contrast to the earthy English hop additions. The style strikes a balance between malt and hops for a more rounded flavour.

Historically, English breweries exported a variety of beer styles to colonies across the British Empire. However, shipping ales to troops stationed in India presented a particular challenge, as the journey took months and the warm climate was too hot for beer brewing without modern technology. To withstand the voyage, Pale Ales were made maltier, higher in alcohol content, and hoppier, as hops are a natural preservative. Over time, taxation has caused the English IPA to assume a lower alcohol content, which in turn has reduced the need for a strong hop presence.

While the Guinness Nitro IPA may not be as bitter or hoppy as some American IPAs, it makes up for it with a very creamy body and smooth drinkability. The nitro leads to a creamy mouthfeel that makes the beer exceptionally drinkable, hitting the palate very lightly and finishing clean and dry on the tongue. The appearance is also similar to the more common Guinness Stout, with a gorgeous cascade of ultra-fine bubbles that settle into a pillowy hat of creamy foam.

It has a fruity aftertaste

When you take a sip of Guinness Nitro Beer, the first thing you'll notice is the smooth, creamy mouthfeel and the distinct absence of bitterness. This is because the IBUs—International Bittering Units—in Guinness Nitro Beer are relatively low, typically measuring between 10 and 15 IBU. To put this into context, an IPA (India Pale Ale) can range from 35 to 70 IBU or even higher. The low IBU level in Guinness Nitro Beer is by design, as it emphasizes the roasted malt character and the unique nitrogenated pour, resulting in a beer that is exceptionally smooth and easy to drink.

Now, let's focus on that "fruity aftertaste" you mentioned. While the initial flavor profile of Guinness Nitro Beer is predominantly roasted malt, with hints of coffee and chocolate, the subtle fruitiness you detect in the aftertaste is not your imagination. This fruity note is a common characteristic of stouts and is often described as plum, raisin, or dark fruit. It originates from the complex interplay of malt, yeast, and the roasting process during brewing.

The fruity essence in the aftertaste of Guinness Nitro Beer is a deliberate and subtle nuance. It is created by carefully selecting specific yeast strains and combining them with particular types of roasted malt. The yeast used in the Guinness brewing process is known to produce ester compounds, which contribute to the fruity aroma and flavor. Additionally, the carefully controlled roasting of the barley malt can impart a range of flavors, from sweet caramel to bitter coffee, and even those subtle dark fruit notes.

To detect this fruity aftertaste, it's best to drink Guinness Nitro Beer at a cool temperature—around 40–45 degrees Fahrenheit (5–7 degrees Celsius). This temperature range allows the flavors to unfold gradually, revealing the initial roasted notes followed by the subtle fruity character. The fruity aftertaste is an integral part of the overall flavor profile of Guinness Nitro Beer and contributes to its complexity and uniqueness. It is a testament to the art of brewing and the attention to detail that goes into every pint of Guinness.

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