I'm having a bit of a dilemma. My dad and I are running a nano-brewery and have had some really good success selling kegs of beer made on our 1 barrel system to local bars. We're just getting into reusing yeast, and I wanted to see what you guys think about this issue. We recently brewed a batch of 1.048 SG beer on 7-29-13. We pitched yeast from our previous batch, basically from the cone to the top of the next fermentor. We transferred the yeast with a sanitized mason jar. The beer has been fermenting for 3 weeks now and has only dropped to 1.022 SG. Our fermentation is typically complete within 3 weeks.
The SG is still dropping, but very slowly. The samples are very cloudy and there is a thick krausen on top of the beer yet. At first, I thought that maybe the beer was contaminated because it had some funky tastes going on (it tasted like baby food early on). I think that odd flavor was from all the yeast that hasn't flocculated yet. I sampled the beer today. The gravity was 1.022 and was slightly tart with some apple/acetaldehyde flavors. It didn't taste contaminated to me. It tasted the way beer often tastes within the first week of fermentation.
When we brewed this batch, I ran into a dilemma where I noticed the wort wasn't evaporating the way it usually does during the boil. We weren't gaining the SG that I would have expected, and then I realized the boil was a little a bit soft. I tried to catch the boil up but I don't think we got a good rolling boil for 90 minutes like we usually do. I originally thought the off flavors I noticed early on were from DMS due to a lack of a strong boil.
What do you guys think? Are these symptoms normal when reususing yeast? Would you recommend doing anything differently?