If you polled a statistically valid number of knowledgeable beer drinkers on what, in their considered opinion, is the most important or influential ingredient in beer (or simply their favourite), I think it's a pretty safe bet that hops would come out on top. You can brew beer with grains other than barley, but barley has been found to be the best. You can make beer with liquids other than water; that would be beer Jim, but not as we know it. If there's better way to ferment beer than with yeast I think we would have found it by now, and if we step outside the German Reinheitsgebot (which originally didn't include yeast because they didn't know about it in 1516) there's a long list of ingredients which can impart flavour to beer such as fruits, nuts, spices and coffee beans, but beer just wouldn't be beer without hops.
Hops are also partly responsible for defining which countries are beer countries and which are not, in that nations traditionally associated with beer (Britain, Belgium, Germany, the Czech Republic) lie within the 'hop belt' of the northern hemisphere, roughly between 40°N and 55°N which, conveniently, is also where barley is easily cultivated (although I don't think I've ever heard of the 'barley belt'), while those further south, countries where grapes grow well (France, Italy, Spain), favour wine over beer (the US is big enough to fall into both camps, and Germany is noted for its wine as well as its beer). The Boston Beer Company went as far as to name one of its beers - Samuel Adams Latitude 48 IPA - with direct reference to the hop belt and included hops from most of the traditional hop-growing countries in the brew.
I don't want to go too deeply into Humulus lupulus and how it works its magic, but a little bit of background will be useful.
The hop plant is a vine which crops best if allowed to wind its bines (yes, that's what they're called) around something so that it can climb freely, usually poles or wires about 15 feet tall, sometimes in a V-shape, sometimes like an 'A', and sometimes over a framework, which is why hop gardens have that characteristic look and why the skill of walking on stilts is a plus.
Many a beer writer (including the late lamented Beer Hunter) has described hops as the seasoning in beer, but hops do much more than the bouquet garni that you toss into your stew or soup. I don't want to get bogged down here with lots of botanical stuff and chemistry - if you really want to go into things like humulone, farnesene, myrcene and isomerisation there are websites for people like you. What hops do, mostly, is balance the sweetness of the sugars that have been drawn from the malted barley by adding bitterness and flavour. After mashing the grain the brewer boils the sweet wort, usually for around 60 to 90 minutes. The bittering hops are introduced almost immediately because the compounds which give beer its bitterness can only be extracted and converted by prolonged boiling. The flavouring and aroma compounds are much more volatile than the bittering elements and would simply evaporate if boiled for too long, so the flavouring hops are added at about 10 - 15 minutes before the end of the boil and the aroma hops a mere five minutes before the heat is turned off. And that's how most beers are made, with three hop additions. Triple hops brewed. Now where have I heard that phrase before...
You'll no doubt be familiar with the Dogfish Head beers 60 Minute, 90 Minute and 120 Minute? Those names refer to the length of time the wort for each of the three beers is boiled, and also that DFH has put an interesting spin on the process by adding hops continuously throughout the boil, which is one reason for the unique flavour of 120 Minute (75 Minute is a blend of 60 Minute and 90 Minute with maple syrup).
After the wort has been boiled and the hops added it's strained and cooled before tossing in the yeast and sending it off to the fermentation tank, but if the brewer wants to beef up that hop character even more there's another little trick they can employ. The wort might be passed through a chamber filled with more hops called a hop back. Because the temperature of the wort is so much lower the volatile oils aren't driven off as much as they were when the liquid was boiling, so the beer-to-be picks up a big boost of hoppy goodness.
Hops additions needn't stop there. They can be added to the firkin (best done in a muslin bag so the tap doesn't get clogged) for a final hit of flavour when cask-conditioned beer is racked from the fermenter or bright tank before being sent off to the pub. That's called dry-hopping. It's just about impossible to dry hop a standard keg, but there's still a way to add some extra hoppiness to kegged beer - you can run the beer through something that does the same kind of thing as a hop back; In this case a device attached to the beer faucet on the tap wall which the beer can be forced through. The most well-known of these contraptions is probably Randall the Enamel Animal from Dogfish Head, although homemade versions are not unknown - Nate Seale, head brewer at (512), built their own version which he named the Hopalope.
You don't have to put hops in a Randall, of course. The possibilities are limited only by the bartender's imagination - fruit, coffee beans, bourbon-soaked cherries, cocoa nibs, bacon, just about anything that adds an interesting layer of flavour to beer can go in. I can tell you from bitter (no pun intended) experience that wood chips, whether mesquite or rum-soaked oak, are a pain in the fundament to get into a Randall, and if you're going to put hops in it, use whole cone hops not pellets.
There are some who say that beer has no terroir, as wine does. The same grape grown in a different country or in a different part of the same country might pick up subtle nuances in its flavour from the soil and perhaps from the climate. While terroir in beer might be less evident than in wine, it's not true to say that it has none, and it's provided by hops (the minerals and salts in the local water also play a part). Hops from different parts of the world have different profiles. European hops are usually characterised as floral, earthy and spicy, while new world hop varieties are well known that familiar piney, citrusy, sometimes even skunky flavour that we find in all those big west coast IPAs. A Fuggles hop grown in Oregon will not produce exactly the same flavours found in a Fuggles grown in Kent.
We're skirting around what was the catalyst for this week's piece so let's, at last, get down to business.
The female flower (looks a bit like a pine cone, see the image above) is what all the fuss is about. Hops start to rot very soon after they're picked so they're dried almost immediately, unless they're going to be used within a week of picking, and even then they're best refrigerated. What they're called at this early stage is where things start to get a bit contentious.
The general consensus is that a whole-cone straight-off-the-plant undried hop is a 'wet hop', and if you brew a beer with whole, fresh, undried hops it's a wet hop beer or ale. Whole dried hops are what's usually referred to as 'fresh hop' if they're less than about a month old; the exact length of time is something that's often debated but a month is pretty much tops. Some say that 'fresh hop' can also refer to the first hops of the season, whether wet or dry. Either way, they're dried and bundled into bales or vacuum sealed in big foil bags (much, much bigger than the ones you get at the homebrew store). Some are left as whole-cone hops, the rest are processed and turned into hop pellets which is how homebrewers usually buy them, and plenty of professionals too. So now we know about wet hop, dry hop and fresh hop. And here we are in wet hop season.
I think we would probably all agree that any plant which is going to be eaten or used as an ingredient is best when just picked and at its freshest. Take a tomato off the vine/apple off the tree/strawberry off the plant and eat it, then try one you bought at the greengrocer. No comparison. Freshly picked fruit and veg has the best flavour, and so it is with hops, but that fresh, wet hop brings an extra piquancy that's lost in the drying process. Beer geeks generally say that the still-fresh hop oils give the beer a smoother, more gentle hop flavour, gently perfumed, and with a little chlorophyll-driven hint of vegetation, maybe like sucking on a grass stem. Just like the herbs you have in your kitchen, you need a lot more wet hops than dried to get the same effect because drying concentrates the flavour. John Harris, from the Full Sail Brewing Company, has said “In order to taste and feel the hops, you have to put them in the right kind of beer. If the beer gets too bitter, you start losing the nuances of the fresh hops." In other words, wet hops are probably wasted in a big double IPA.
Sierra Nevada Northern Harvest might be the granddaddy of American wet hop beers but it's far from being the only one. In fact it's not even the only one that Sierra Nevada makes nowadays. Southern Harvest (with hops flown in from New Zealand), Northern Harvest, and Sierra Nevada Estate Homegrown Wet Hop Ale, made with ingredients grown on Sierra Nevada's own farm, are three that I particularly look forward to each year, and not just because this kind of seasonal is so tied to the growing year that the breweries can't put it on the shelves two months early like they do with Oktoberfests and Christmas beers. Hoo hah!
Wherever you may be, try to get your hands on a wet hop ale this autumn. Your taste buds will love you for it.