Hops 101: the what, where, how, and why of hops
Hops. You probably know that they are those mysterious little buggers that make beer, and therefore, life, better. You know that brewers do magical things with them. But would you actually know a hop if fell over one in the street? When you’re downing your IPA and knowledgeably declaring it to be like, totally hoppy guys, do you really know the why and how of what you’re talking about? No? Don’t feel bad. It’s one of those things we tend to leave to the experts and just be grateful for, isn’t it. But we’re going to tell you the four most important things you need to know about hops. They will make you smell and taste your craft beer with new appreciation and look up your favourite brewers with even more admiration that before. This humble and, let’s face it, not very attractive plant, is a powerful part of any beer drinker’s life and we reckon it’s worth getting to know a little better.
Hops are the flowers of the plant humulus lupulus. The smarty pants among you will know that this translates to something like “wolf plant”, apparently so-called by the Romans because it grew wild among willow trees like a wolf among sheep. We quite like that – makes it sound a bit dangerous and therefore quite cool, doesn’t it. And that’s before it’s had anything to do with beer. Some of you will also be excited to know that hops come from the same plant family as cannabis. This is basically irrelevant for our purposes but we knew you’d enjoy that little tidbit and it’s a nice one to have up your sleeve when conversation dries up a bit between rounds.
Anyway, for commercial purposes, the wolf has to be tamed and so the hop plant is trained around poles or tall trellises to give it maximum light and is harvested by beautiful young virgins. Just kidding. It’s harvested with big-arse specialised equipment. Hops also need plenty of water but, conversely, do better in drier climates, not tropical humidity. So commercial hop growth is actually limited to a fairly restricted number of locations. By far the majority of the world’s hops are grown in Germany, Czech Republic, China and the north west of the USA. We will get to Aussie hops later.
Hops are added to beer for three key reasons: aroma, flavour, stability. The hops flower secretes a substance called lupulin when it’s boiled. Lupulin contains essential oils, bitter acids, and resins – in other words, the stuff that gets those jobs done. Let’s break it down a bit.
Aroma – hops give a very distinctive and often pungent range of aromas to a beer. They might be spicy, herbal, piney, citrusy, grassy, floral or a combination depending on the types of hops used. The aroma comes from the essential oils, but they can dissipate quite a bit during the boil so brewers wanting more substantial hop aromatics will add more hops at later stages of the brewing process to really nail down that pungent smell. So take a big whiff of your next beer and enjoy.
Flavour/bitterness – hops are used to balance out the sweetness of malt sugars to varying degrees. Different hop varieties have different level of bitterness, or alpha acid content if you want to get all scientific about it. Beers will have different International Bittering Unit (IBU) measurements depending of these levels. Your big hop bombs make it all about the hop bitterness and let the malts do their thing in the background. Similarly, even if you’re strictly into, say, chocolate stouts and can’t get enough malt (no judgement – you’re missing out, but that’s on you), the hops are STILL THERE. Even used sparingly, they cut through sweetness, giving a cheeky hint of spice here or a tickle of citrus there. You can’t escape them. And if you can’t cope with that then go buy a chocolate milkshake and leave the beers to us.
Stability – hops are a natural preservative which is handy, right? The beta acids produced by the lapulin help to ward off the bacterial beasties that can contaminate the wort while the fermentation process is still producing enough alcohol to stop bacterial growth. After helping out early on in the process, the hops continue to contribute to a longer shelf life than a beer might otherwise have. Beer history buffs will often tell you that we have these efficient antibiotic properties to thank for the rise of the India Pale Ale which, heavily hopped, made it all the way from England to India without going off. Can you imagine the relief when those beers arrived? Man, those would have been happy afternoons for the Raj.
This is increasingly an area of much experimentation and innovation but we’re going to keep it relatively straightforward so your eyes don’t glaze over. Here goes.
For the purposes of beer brewing, hops come in three forms:
- Whole-leaf hops – these are simply the dried cones
- Pellets – the hops are compressed into pellets that look like rabbit food
- Extracts – the alpha acids and essential oils in liquid form
- Fresh or wet hops – unprocessed, pretty much plucked straight from the plant
Any of these forms can be added to the kettle during the boil of the wort (which is the sugary water and malt mix) for varying effect. Whole leaf hops, for example, have great aromatic qualities but will soak up a lot of the wort. Pellets can be a more economical and efficient option and are the mostly widely used form.
Hops that are used for bittering effect are usually added toward the beginning of the boil because the alpha acids you want working their magic are activated, so to speak, by boiling. The technical term is isomerized. Write that down for the test later on.
Hops that are being used for flavour and aroma are generally added a little later in the boil so that the essential oils don’t dissipate too much and lose their pungency.
Dry hopping is the other technique you’ll hear lots about. It involves adding hops to the beer after fermentation and leaving them there for a couple of weeks. This strategy is great for producing a really bright, fresh aroma while the effect on taste in much more subtle.
Still with us? You – up the back – pay attention.
Ok, this is our last section. Then you can all run out to play. And drink.
A bit posh sounding, these are your prize central European hops and they are all about smooooooth bitterness and lovely aroma. There are four: Hallertau, Saaz, Tettnanger, and Spalt. Think woodsy, peppery, a little spicy, nicely floral. Like taking a walk through a German meadow or a Czech forest. Or so we imagine.
Many English beer styles are great for showcasing the bittering qualities of their hops. The ones to look out for are: Fuggle (if you remember only one thing from this lesson, we guarantee that “Fuggle” will be it), Challenger, and Golding. A bit earthy, lemony, and yes – you guessed it – a bit tea-like.
Subtle, restrained, meek even. JUST KIDDING. As if. US hops are as bold and intense as you would imagine. And there is huge variety. Some of the biggies are Centennial, Columbus, Chinook, Citra, Cascade. Citrus is going feature heavily in your experience of US hopped beers but the range of aroma and flavour profiles produced is epic.
Australian & New Zealand Hops
Nelson Sauvin and Galaxy are the biggies down under. Galaxy is all passionfruit and peach and orange. NZ’s Nelson Sauvin is aromatically reminiscent of the Sauvignon Blanc grapes that are grown in the same region. Think lychee and melon and gooseberry.
So there you have it. Hops 101. This merely scratches the surface of course but at least now you know your IBU from your IPA and can name drop Fuggle and Chinook like a pro. Hands up then if you reckon hops are awesome. Yep, we think so too.