I'm going to brew a Kölsch soon with about 25 IBUs. I was planning on using Hallertau Hersbrucker for bittering. However, after I bought the hops I noticed they only have 2.3% alpha acid content. Using the calculator on Brewersfriend.com I calculated that I will have to use 100 grams at 60 minutes (~3.5 ounces I think) to achieve 25 IBUs.
I've never added this much hops to anything but huge stouts and IPA's so I'm worried about the hops imparting undesirable flavors.
Batch size: 25 liters
- Should I use some other hop variety with higher AA content for bittering instead, or should I trust the calculator and use the Hallertau Hersbrucker hops?