Hop bitterness is a measurable number using International Bitterness Units (IBUs). Generally, anything above about 40 IBUs is “pretty bitter” to the uninitiated palate, below about 30 IBUs is moderate and not too bad on bitterness, and below 10 IBUs would be like a Bud Light level of bitterness. Maximum IBUs possible in any beer is about 80 to 90 IBUs, which of course is really, really bitter!
It’s pretty easy to calculate IBUs for any recipe, as long as you know the volume being brewed, ounces (oz) of hops, the timing of the hop additions, and the alpha acid percentage (AA%) of the hops. Google tells me that Simcoe hops have an average alpha acid of 13%, so I’ll use that for the following example calculation. These calculations are designed for pellet hops used in 5 gallons final boil volume, 60-minute boil, @ approximately 1.060 OG. I have designed this IBU calculation method (which I like to call “the Taylor formula”) to come super-close to what is calculated using the official “Tinseth” formula. What you need to calculate:
3.6 * oz * AA% = IBUs from bittering additions, with hops added @ about 60 minutes
1.6 * oz * AA% = IBUs from flavor additions @ 10-15 minutes
0.6 * oz * AA% = IBUs from aroma additions @ 5 minutes
Add all these together, and then add another +1.5 to the final total. Dry hops add zero bitterness (at least in theory).
So in your case, I’ll first assume that you are brewing 5 gallons. If not, then you need to multiply your result by 5 and divide by the volume in gallons that you are brewing. Not too difficult. I’m also assuming your AA% is 13%. You can fix this if it’s different. So, your calculation:
3.6 * 1/2 * 13 = 23.4 IBUs from bittering additions, with hops added @ about 60 minutes
1.6 * 1/2 * 13 = 10.4 IBUs from flavor additions @ 10-15 minutes
0.6 * 1 * 13 = 7.8 IBUs from aroma additions @ 5 minutes
Then add an extra 1.5, so the grand total is 1.5 + 23.4 + 10.4 + 7.8 =
43 IBUs for 5 gallons of this beer. If you’re brewing a smaller volume (V), you’ll get even more IBUs, at a ratio of 5/V.
That’s “pretty bitter”. If you want to reduce this, then I would suggest moving some of your bittering hops down to the 5-minute mark and knock the IBUs back into the 20s. Easy as that. After you run this calculation a few times, it becomes old habit.
You can also pump your recipes into good software such as BeerSmith or ProMash or StrangeBrew or a host of others, and they’ll do all these calculations for you.