Why are hops added to beer?

East Kent Goldings growing in the field in Kent

When you think of hops, it is going to make you think of beer. But why are hops added to beer anyway? And what difference does it make when the brewer adds the hops. Today I'm going to talk you through why hops are added to our beer, and the different ways the brewers can create aromas and flavours, depending on when they add the hops to their beer.

Why are hops added to beer in the first place?

Before hops are added to beer, a mixture of herbs and spices was added to add flavour and this was called gruit. It was discovered, however, that hops had preservative properties, and that they could add bitterness. So eventually, these became the norm in our beers. Think about the stories you hear of IPAs - India Pale Ale - being exported to India, and how by adding more hops, they were able to preserve the beer for longer.  Hops are also added for flavour and aroma as well as bitterness.

Why are hops added to beer from different countries?

A Kent hop field just before harvest growing British hops

It depends on where the hops come from to what aromas and flavours will be added to the beer.  Hops are grown in many places, but there are four established main regions for hop growing. These are Germany and the Czech Republic, Britain, America, and New World hops such as Australia and New Zealand. German and Czech hops are going to add characteristics such as spicy, floral, perfumy, and sometimes minty. British hops will give you earthy, herbal and woody notes. American hops give those classic piney, resin and citrus notes that people love in their big IPAs, and your New World hops coming from Australia and New Zealand and going to give a big whack of tropical and exotic fruits and sometimes slightly savoury. Think about Nelson Sauvin, which is crossed with the Sauvignon Blanc grape, that's going to give you vinous and slightly savoury notes.

Why are hops added to beer other than for flavour?

Inside a hop - the yellow is lupulin which contains the alpha acids and essential oils - photo courtesy of @saltyinsheff

Hops don't only add aromas and flavour however, they also add bitterness which is a very important component of hop additions. Hops can be categorized into two sections - bittering and aroma. And then there are ones that crossover that are called dual purpose. When we're looking at bittering hops, they need to have a high percentage of alpha acids. These alpha acids when boiled during the brewing process are isomerized, creating the bitterness that is needed to balance out the sweetness added by malt. Even an imperial stout, which has really low bitterness, will still have some hops added to add that balance. However, during that boiling process, if hops are added right at the beginning, the aroma and flavours that come from essential oils are going to be boiled away. So that means we need to consider when hops are added.

Why are hops added to beer at different times?

Green hops added to the wort during the boil

A brewer will think very carefully about when they are going to add their hops.  Added right at the beginning of the boil process, you're going to get more bitterness.  Added towards the end of the boil, you're going to start to retain some of the aromas and flavours. But for styles such as big IPAs or New England IPA where we want a big whack of those tropical fruit flavours, then the hops need to be added in possibly the whirlpool while the beer is being cooled, or even in a process called dry hopping, which is after fermentation has happened. This way the oils are preserved within the beer, and we save those aromas and flavours.

Why are hops added to beer – many reasons!

Freshly picked hop cones - photo courtesy of @saltyinsheff

There are lots of different considerations that brewers and drinkers need to take when deciding why hops are added to beer. Is the brewer trying to add brittleness or are they trying to add aroma and flavour?  What aroma or flavour are they trying to make? There are even beers that used aged hops, so they still get the preservative properties, but don't get the bitterness or the aromas and flavours, because the style doesn't require it. Have a look at lambics for that.

So hops are a really important addition in our beers, and there are many ways that they can influence what we taste. If you'd like to learn more about different hop varieties, check out these blog posts on different hop varieties. Let me know in the comments what hops you'd like to know more about. And if you'd like to build some vocabulary about hops for when you're tasting beers, come join us in Build Your Beer Vocabulary, my signature beer tasting course.  We do some sensory exercises to help you build your understanding of what hop flavours and aromas are all about. Check it out on the service page here.