I'm trying to troubleshoot a subtle sweet aftertaste in my beer. It's my first lager, a German pils so it's out of style. Primary fermentation has just finished and about to be cooled for lagering. OG was 1.043 and SG/FG is 1.007.
I'm trying to troubleshoot whether it's something in my recipe (see below) or an off flavor in my process (maybe acetaldehyde or esters?).
Recipe is a German pils, 3 gallon batch
4.5lb pils
3oz carapils (could this contribute?)
Hallertauer mitt hops: 1 oz @60 min, 0.5oz@15 min, and 0.5oz@1min, for an estimated 34IBU.
Here's my process:
Mini BIAB all-grain, started mash at the recommended 149F but by the end (90 min), it had dropped to 139. Still hit 80% efficiency. Vigorous boil for 90 min with wyeast yeast nutrient at 5 min.
Pitched dry cellar science German yeast, 12g packet into cooled wort (54), and held at 52-55 with an inkbird and chest freezer using temperature probe on side of carboy. On day 8, fermentation was slowing down, and SG was at 1.015 so I did a D-rest at 63 for 3 days. Ramped down 3F/day to 49 and about to lager and here I am, at a FG of 1.007 and this sweet aftertaste.
Any ideas what may have caused this?
The yeast is supposed to ferment dry but not many reviews are out there confirming this. Unfortunately it was the only dry. Lager yeast my LHBS had in stock and I wasn't up for a starter. I don't think I underpitched (which may cause esters). The yeast was specified for 54-62 and I kept it below 54/55 but maybe I should have gone even lower? Could the low mash temp cause this? I've read too high can create unfermentable sweetness but I think that would still contribute to SG which doesn't seem the case here.
I'd welcome any feedback.