Oily patch on surface of kegged beer

[khillian]

Hey HBT,

I have been dealing with bitter harsh astringent flavors in my beers of late. Deep cleaned and trying to track the source of the issue. Took apart my kettle ball valve, iodophor cleaned most of my equipment (normally use starsan). Replaced all hoses, airlocks, and o-rings on kegs.

This last batch was OG 1.068 and FG 1.013, fermented for 7 days (4oz dry hops added to primary loose on day 4) with WYeast 1056. Kegged on day 7 and it went right into the kegerator to chill/carbonate. After another week the beer also had this bitter harsh flavor, decided to dump it.

Opened the keg this morning and saw this oily looking patch in the center of the keg. Could this be some sort of infection or just hop oils/star san?

 

[WBB]

I would say that is remnants of the hop oil from the dry hopping.

 

[Horseflesh]

Looks like hop oil to me.

I would suggest doing a similar brew next time, and taste it frequently to see if you can determine if the off flavor builds slowly or comes after a particular step. I'd also remove some from the fermenter with a measuring cup, put it in a soda bottle, and force carb with a carbonation cap--eliminating the keg and associated transfer tubing 100%.

Other thoughts:

Astringency is often mentioned with mash pH problems.

Is it possible that there is an ingredient in common which may itself be off?

What's the fermentation temperature? Seems unlikely to cause astringency, but...

 

[RM-MN]

Hey HBT,

I have been dealing with bitter harsh astringent flavors in my beers of late. Deep cleaned and trying to track the source of the issue. Took apart my kettle ball valve, iodophor cleaned most of my equipment (normally use starsan). Replaced all hoses, airlocks, and o-rings on kegs.

This last batch was OG 1.068 and FG 1.013, fermented for 7 days (4oz dry hops added to primary loose on day 4) with WYeast 1056. Kegged on day 7 and it went right into the kegerator to chill/carbonate. After another week the beer also had this bitter harsh flavor, decided to dump it.

Opened the keg this morning and saw this oily looking patch in the center of the keg. Could this be some sort of infection or just hop oils/star san?

You WHAT??? You kegged the beer before the yeast had a chance to settle, left it chilled in the keg for another week, then decided to dump it because it has a harsh flavor? Someone should kick some patience into your behind. Your harsh flavor is from the yeast, not infection. Pull that keg out of the kegerator, let it set where it is warm (low 70's) for a couple weeks, then chill it again and sample a couple days later.