Brewing with fresh hops all year long
Brewing with fresh hops has long intrigued me. It is fairly intuitive that fresh hops would have different flavors than dried hops, and being able to grow a key ingredient for your brew has a certain appeal. And, Vancouver happens to be a great location for it as it has a good climate for growing hops; hops can be seen in the back yards of many homes around the city and wild patches can even be found growing under bridges and in parks. The Fraser Valley region (an hour or so east of Vancouver) was a significant global source for hops up until a few decades ago, so the region has certainly proven its ability to produce hops of outstanding quality.
A friend living on a nearby island contacted me last autumn and asked if I wanted fresh hops from the wild vines growing on their property. I was interested but declined, as nothing was known about the type of hop (aroma, acid content, etc.) which meant that I would be brewing blind. This autumn, however, I took him up on his offer. He let me know which day he was going to pick, so that I could be ready to brew (it's best to use them before they start to wilt). He showed up with about 2.5kg/5lbs of extremely fragrant, sticky, and bright green cones. I had selected a basic pale ale recipe (organic two-row and a bit of crystal 60L with 1056 ale yeast) as I wanted to feature the hops, and was brewing a 19L/5gal batch in the Small BIAC. As I didn't know the variety or acid content, it was difficult to know how much to use, but due to the typical moisture content of fresh hops being about 70% and dried hops being only about 10%, I knew to use about three times as much hops as normal.
The beer was delicious. The acidity was slightly more prevalent than expected and woody/spicy/herbal aspects were dominant. Based on its acidity, and flavor profile, and given that it was growing so well on Bowen Island (which receives about 165cm/65in of rain each year, so mildew might kill a weaker variety) I suspect that it is one of the hardier varieties such as Nugget or maybe Northern Brewer.
I had a lot more hops than I needed for that 5 gallon batch, so I put them directly into Ziplock freezer bags, sqeezed out as much air as possible, and placed them in the deep freeze. Some sources on the web recommend drying first, but I didn't have the time (or space) to dry them and I don't see how the freeze would have a deleterious effect on the acid content or aroma profile (as long as they were added directly to the boil and weren't thawed before use). You can see in the picture above that the freeze turned the hops slightly darker in color (not as bright green), but they look almost identical to fresh or dried hops when coming out of the boil.
To test the capability of hops to retain their usefulness after being frozen for a period of time, I used the frozen hops when brewing a 'West Coast Chocolate Rye Beer' last month—they had been in the freezer for almost two months. I wanted a slightly 'warmer' beer for Christmas this year without it being heavy, and wanted to experiment with rye a little so thought a toasted rye might be nice; and the spicer aspects of the 'Bowen' hops would complement the rye nicely. I poured my first pint of rye beer yesterday and it was delicious. The fresh, frozen hops performed beautifully and I couldn't detect any adverse effects of freezing. (Note: I have seen references to a German study that demonstrated that frozen hops were effectively identical to fresh hops but haven't seen the study myself—if anyone has seen it I would appreciate hearing about it.)
I intend to keep brewing with these hops to monitor their performance. If it goes well I'll likely be brewing with fresh, frozen hops throughout the year. And, if all goes well, this coming summer you'll probably see vines growing in my back yard.
Glad to see this. I started my own hops patch in my garden last summer and never thought about freezing them while still fresh.