I sent some of my willamette hops in for testing at Alpha Analytics. The alpha acid results came in at 3.4%. The norm is 4% to 6%. Beta acid results were 3.7% with the norm being 3.5% to 4.5%. I plopped an ounce in a keg of pale mild for a week and it worked fine as a dry hop. Should I have any concerns about using them during brewing? Does anyone know if it’s possible to boost alpha acids through growing techniques?
You most likely harvested them too early. Next year wait an extra couple of weeks until they really start to turn brown. Also keep them watered well and free from pests like aphids and spider mites.
I should have mentioned the test was done on my combined harvest from my two growing spots. The hops were beginning to turn brown. I was thinking they might have been harvested late. I harvested them two weeks later than last year, but we had a later start and a cooler summer this year than the previous year. I’ve since used them, and they do the job just fine. More of a theoretical question than an ‘oh no my hops suck’ question. No pests at all - knock on wood - this year.
Yeah, it sounds like you harvested too late, which could be on reason for the lower AA. I find that the AA of my homegrown hops seems to vary based on weather. It seems to be higher when it’s a hotter summer.
I wouldn’t have any concerns using them in brewing; no more than any other hops. I’ve heard all sorts of things about %AA in hops, including cones on certain parts of the bine tend to have higher/lower %AA, along with the things mentioned here. Not sure if it matters much so long you are combining all the flowers to package and/or send off for analysis. For mine, I tend to use whatever info I can find on %AA from the same variety in my area (VT) and have gotten analysis done once myself on 3 varieties. In my experience with these data,(thanks U of Vermont’s Extension hops trials) %AA in VT tend to be lower than published ranges for the same varieties. I harvest based solely on feel and aroma.