weird off flavor/texture, any ideas?

[Johnnyare]

I jumped into homebrewing going all-grain. I have been fortunate and have been pleased with my results. I wanted to brew a batch but knew I did not have the time for AG so I picked up an Amber kit. I followed the directions to the letter save for two points. Point one: I did not remove the wort from heat when adding my extract. Point two: I added a half once of liberty when racking to the secondary. My issue was an oily mouth feel and a slight off flavor that I can't describe, but my brother says that it sounds astringent from my description. He says that he does not taste it. He did notice the oily mouth feel but only after I pointed it out. I had the fermentor close to a heat vent so my temps. might have fluctuated. I did have it covered with a blanket and in a cardboard box so I don't think that the heat vent would affect it that much and when I took the temps they were always in the mid 60's. I brewed an all grain IPA the next week that had neither of the minor problems as the amber. A friend said that my IPA was excellent but not being an IPA fan (wussy) would love it if I tried the same recipe with the hops cut in half. I did and bang both of my problems were back slightly milder this time but still noticeable to me. This perplexes me. I thought it might be scorching of the extract, but then it would not show up in the AG wussy IPA. The fermetation location was the same for all batches so the temp. does not seem to be the issue. I used the same hops as the full bore IPA, just halved so the hops does not seem to be the issue. It makes me think of contamination but from my limited experience this was not a contaminated or dirty flavor. Okay... so anyone have ideas. Sorry I took so long to get to my question.

 

[Demus]

It may fade with age. It's likely the flaw was present in your IPA as well, you just couldn't taste it in the hoppier version. It sounds like your temperature control is fine. How's your pitch rate and aeration?

 

[Pie_Man]

What was your recipe and brewing process?

Astringency has several potential causes. It could result from tannin extraction due to over crushing your grains or over sparging. It could be that your water is too alkaline. It might also be an acetobactor infection.

 

[progmac]

oily makes me think diacetyl. the general taste descriptor is buttery. how much yeast are you pitching, what is your OG?

if i had to guess i'd say you are fermenting cool and underpitching the yeast.