All grain noob and what i think is astringent taste.

Brew was caribou slobber from NB. Brewed as directions stated. Allthough my direct fire mash tun got towards 170f at one point. Wort tasted extremely bitter after boil but after fermentation and kegging it taseted great. now 2-3 weeks later it has a harsh what the wife and I think is astringency to it. It bitterness on the back of palate. Like I said it was great right after carbing but I get the green beer farts so it stored at 38 in keezer till this past weekend when we noticed the off flavor. This also happened with a New Belgium 1554 clone (extract) from austin Homebrew. As soon as bottles carbed they tasted great. Local Liquor store manager even wanted me to enter contest. But several weeks later bam! same nasty flavor? Im pretty thorough in cleanliness and sanitation but could that be the culprit? Also the 1554 I attributed to a heat wave in the room it was stored in it got over 80 at one point last summer. Its an extra bedroom so ac duct was closed. Not the case with most recent AG Caribou Slobber though.

Some people note a harsh bite from carbonic acidity (at least, so I've read) when the beer is freshly carbonated. It would seem that the common experience is for it to be harsher in that first week on forced CO2, and significantly better by week 2 or 3. It could be a sanitation issue... it could be that the beer is going bad from a bug, but if it were me, I would manually vent the beer a bit (maybe several times) and store it at appropriate temperatures for a while, and then try it again on a little less CO2. But it's purely guessing on my part. I would think that all of your possible problems are A). infection, B). chemical contamination, C). problems with your CO2 levels, D). dirty lines... just spitballing.

The 170 mash is history... if it was good after you carbed, then you like the product. Getting the temp too high stops some of the enzymes from doing their thing, thus limiting how much fermentable sugar you get... it should probably make the beer darker, and maybe maltier/sweeter to some extent.

Good luck! I'm sure you'll get some awesome pros here to throw in their two cents!

<----NIU Husky.

Well the 1554 was bottled with priming sugar and the Caribou was also carbed via sugar all be it in keg no force carbing here yet. Im leaning more towards the sanitation all though my bottles do a full cycle in dishwasher followed by rinse in starsan. Ive read tonight on all the cons of dishwahser so that will end asap! The keg was oxycleaned and then soaked with star san from spray bottle. Maybe its a flaw in my fermentor sanitation? But im still perplexed as to why it starts good while green then goes south? the 1554 bottle did seem to get over carbed infact when I dumped them it was like poppong champagne! My first all grain was a total successs and was also kegged too bad it s gone now! A 312 clone frome St. Charles Home brew shop. Mo off flavors at all and nothing has changed. tomorrow Im cleaning the snot out of all buckets etc...

I am pretty sure it has something to do with sanitation or carbonation too. If the beer tasted good as soon as it was carbed, then I think everything up to that point was done correctly. The passage of time could have led to contamination due to bacteria, or something wrong with the carbonation. One way to tell is to smell the beer. If it smells perfectly normal, then I would lean towards it being a CO2 issue. Also, why not tap some and let it hang around and go flat, and taste it again. Same taste? If the taste clears up a little then it is defnitely a CO2 thing. I like the venting idea from TapeDeck too.

Well I started venting yesterday when should I check it again(taste etc...)? Will I have to re carb?