If brewing is a kind of magic, fresh ingredients can only strengthen the spell. Any gardener will tell you that food you’ve grown will make a better meal. Where homemade malt is a challenge and culturing wild yeast won’t always pay off, growing your own hops is relatively easy. The bines grow quickly through the season, and it won’t take long before it’s time to harvest. As you amass your pile of hop flowers, you might be a little stymied over how to use this homegrown bounty.
You’ve had plenty of experience with store-bought hops: whether pelletized or whole leaf, they’re dry and compact. They’re also nicely labeled with their alpha acid percentage (AA%). By contrast, freshly harvested hops have a much higher water content, which makes a huge difference when it comes to working out recipe weights. On top of that, you won’t really know what AA% you ended up with. If you know the variety, that can give you a ballpark estimate, but your climate, the weather during the growing season, and your soil conditions can all have unpredictable impacts.
But don’t throw in the towel! While wet hops offer some challenges, there are plenty of rewards, as well. When commercial hops are dried and shipped around, their essential oils change character and intensity. You’ll gain the best understanding of those differences by brewing a wet-hop beer. You can use the fresh hops throughout your recipe, but they contribute the most as either a very late aroma addition (ideally at flameout) or in a lower temperature hop stand after the boil. Remember to account for the extra water content; you’ll need to use five or six times the weight you might normally consider.
If you do decide to brew a wet-hop beer, you’ll want to do that as close to harvest time as possible, but you can also dry your hops for later. Some people use their oven or food dehydrator, but building a hop dryer is simple and inexpensive. That will bring the weight in line with hops from the homebrew shop, but you’ll still have the problem that your AA% is unknown. Many homebrewers handle this by limiting their use to aroma and flavoring, where the bitterness is less of an issue, but if you want to use them throughout your hopping schedule, there are some ways to make it work:
Pay for an analysis - While this used to be fairly expensive, prices seem more reasonable now. You’ll likely need to send in an ounce or two (30-80g), along with $30-50. The AA% you get should be as accurate as the label on your commercial hop packages.
Iterative brewing - You can save that money and do your own in-place experiment. Assuming you know the variety, take a guess at the AA% and brew a batch. Pale ale works well as a base, because it accommodates a good range of bittering. If the bitterness doesn’t match your expectations, adjust the recipe and try again. It might take a few batches to hone in on a decent estimate, but then you can use that number for your hops in other recipes. The bonus is that those experimental batches should all be drinkable.
Calibrate against known quantities - You can get a decent idea of how bitter your hops are by testing against a set of hop teas, each with a known bitterness level. Ideally you should use the same variety of hops that you grew. Next week, I’ll cover this technique in more detail.
Do your own lab analysis - If you want to play chemist, it’s possible to do your own lab analysis by titrating a sample with phenolphthalein. Dr. Leonard Perry has a brief write-up that includes instructions originally shared in the old rec.crafts.homebrewing newsgroup.
Of course, to use homegrown hops, you need to plant them first. Winter is a good time to start thinking about this -- plan your garden, track down some rhizomes, and build that hop dryer. Good luck!