[Village Taphouse]

Also, I'm not sure I'm understanding the diacetyl test where one sample is heated.  I am using plastic fermenters with spigots and usually 12-13 days after brewing I will closed-transfer the beer from fermenter to keg.  Wouldn't I just be able to grab a small sample though the spigot and give it a smell & taste test?  I can absolutely detect diacetyl.  Is the heated-sample method meant for people who have a harder time picking it up?

Also, when I move my fermenter from fridge to the basement floor, I typically rouse it at that time and then let it settle for a week and then transfer.  I have a pale ale that I took out of the fridge on Friday and I roused it then.  I roused it again yesterday and then again this morning... gently.  I would typically transfer this beer Thursday or Friday of this coming week and then brew with that harvested yeast again over the weekend.  I will grab a small sample prior to transfer and check for the big D. 

[Village Taphouse]

I actually bring beers upstairs in the winter when I want to warm them up in the back half of fermentation so that they are around 70. I feel that once the bulk of fermentation is done colder warming up doesn’t do any harm like unwanted esters, at least that’s my experience, so I kind of go for it with the warm temp.
I also find that after high krausen the exothermic temp increase is way less so the beer stays close to ambient temp.

Yeah, that's a thought.  Except for the obligatory Um, Ken... why is there a fermenter in the guest bedroom!?!? 

[majorvices]

Those heat wraps are awesome If you insulate your thermoprobe against the fermenter with a piece of cloth/papertowel/bubblewrap/stryrofoam and wrap the heat wrap around the fermenter and plug into your thermostat you can keep the temp of the beer whatever you want (above ambient).

[Village Taphouse]

Those heat wraps are awesome If you insulate your thermoprobe against the fermenter with a piece of cloth/papertowel/bubblewrap/stryrofoam and wrap the heat wrap around the fermenter and plug into your thermostat you can keep the temp of the beer whatever you want (above ambient).

I've never owned one of those and I feel like I was always working to try to keep fermenting beer cooler.  But I guess I wasn't seeing what might happen in a Chicago-area basement in the winter.  This spot I have between two fridges is warm.  The beer probably reaches 68-70°.  But if this first light step in the right direction is not enough, I will look into a heat wrap.  Thank you for the suggestion. 

[hopfenundmalz]

Also, I'm not sure I'm understanding the diacetyl test where one sample is heated.  I am using plastic fermenters with spigots and usually 12-13 days after brewing I will closed-transfer the beer from fermenter to keg.  Wouldn't I just be able to grab a small sample though the spigot and give it a smell & taste test?  I can absolutely detect diacetyl.  Is the heated-sample method meant for people who have a harder time picking it up?

Also, when I move my fermenter from fridge to the basement floor, I typically rouse it at that time and then let it settle for a week and then transfer.  I have a pale ale that I took out of the fridge on Friday and I roused it then.  I roused it again yesterday and then again this morning... gently.  I would typically transfer this beer Thursday or Friday of this coming week and then brew with that harvested yeast again over the weekend.  I will grab a small sample prior to transfer and check for the big D.

The forced test makes the diacetyl easier to detect, and if the precursor is there it will oxidize faster at higher temps.

[hopfenundmalz]

Also, I'm not sure I'm understanding the diacetyl test where one sample is heated.  I am using plastic fermenters with spigots and usually 12-13 days after brewing I will closed-transfer the beer from fermenter to keg.  Wouldn't I just be able to grab a small sample though the spigot and give it a smell & taste test?  I can absolutely detect diacetyl.  Is the heated-sample method meant for people who have a harder time picking it up?

Also, when I move my fermenter from fridge to the basement floor, I typically rouse it at that time and then let it settle for a week and then transfer.  I have a pale ale that I took out of the fridge on Friday and I roused it then.  I roused it again yesterday and then again this morning... gently.  I would typically transfer this beer Thursday or Friday of this coming week and then brew with that harvested yeast again over the weekend.  I will grab a small sample prior to transfer and check for the big D.

The forced test makes the diacetyl easier to detect, and if the precursor is there it will oxidize faster at higher temps.

[tommymorris]

Also, I'm not sure I'm understanding the diacetyl test where one sample is heated.  I am using plastic fermenters with spigots and usually 12-13 days after brewing I will closed-transfer the beer from fermenter to keg.  Wouldn't I just be able to grab a small sample though the spigot and give it a smell & taste test?  I can absolutely detect diacetyl.  Is the heated-sample method meant for people who have a harder time picking it up?

Also, when I move my fermenter from fridge to the basement floor, I typically rouse it at that time and then let it settle for a week and then transfer.  I have a pale ale that I took out of the fridge on Friday and I roused it then.  I roused it again yesterday and then again this morning... gently.  I would typically transfer this beer Thursday or Friday of this coming week and then brew with that harvested yeast again over the weekend.  I will grab a small sample prior to transfer and check for the big D.

The forced test makes the diacetyl easier to detect, and if the precursor is there it will oxidize faster at higher temps.

Having two samples makes it easier to taste the difference. One was heated to cause the diacetyl to form. The other was not. Precursor is not tasteable for us humans. If they don’t taste the same after hearing and cooling one of the samples, there is a problem.

Has anyone trained dog to detect diacetyl or better yet precursor? Seems like a worthy endeavor. You could make a career traveling from brewery to brewery helping save beer one batch at a time. I’m thinking the dog trainer would have sample privileges also of course.

[Bel Air Brewing]

My threshold for detecting diacetyl is quite low, meaning it's very easy to pick up, even in minute amounts. I think this is true of most educated beer drinkers.

Our beers have had a complete lack of this issue...maybe we are just lucky? I personally would dump the beer if this was detected. I do not like it. Not one bit.

[denny]

My threshold for detecting diacetyl is quite low, meaning it's very easy to pick up, even in minute amounts. I think this is true of most educated beer drinkers.

Our beers have had a complete lack of this issue...maybe we are just lucky? I personally would dump the beer if this was detected. I do not like it. Not one bit.

It has as much, if not more, to do with physical differences as education and training.

[Village Taphouse]

If a higher temp near the end of fermentation (and after fermentation) has anything to do with it, location could be key.  A beer sitting on the floor in Texas (my son tells me that Texas doesn't have many basements) compared to a beer sitting on a concrete basement floor in Chicago in the winter could be as far as you need to look.  As mentioned... all spring and summer with 940 and Bayern... no diacetyl.  Now this fall with cooler temps and WLP001 and two beers with some diacetyl.  I'm not trying to make it easier to explain but it could be that simple. 

[tommymorris]

If a higher temp near the end of fermentation (and after fermentation) has anything to do with it, location could be key.  A beer sitting on the floor in Texas (my son tells me that Texas doesn't have many basements) compared to a beer sitting on a concrete basement floor in Chicago in the winter could be as far as you need to look.  As mentioned... all spring and summer with 940 and Bayern... no diacetyl.  Now this fall with cooler temps and WLP001 and two beers with some diacetyl.  I'm not trying to make it easier to explain but it could be that simple.

It’s definitely easier to warm up beer in the South.

I think having plenty of yeast is also important. I can’t recall having had diacetyl issues since moving to 2.5 gallon batches. I over pitch almost all the time now since  I always pitch a whole pack of yeast for half a batch.

I also get all my beers into the mid 60’s in primary for a few days.

[Village Taphouse]

If a higher temp near the end of fermentation (and after fermentation) has anything to do with it, location could be key.  A beer sitting on the floor in Texas (my son tells me that Texas doesn't have many basements) compared to a beer sitting on a concrete basement floor in Chicago in the winter could be as far as you need to look.  As mentioned... all spring and summer with 940 and Bayern... no diacetyl.  Now this fall with cooler temps and WLP001 and two beers with some diacetyl.  I'm not trying to make it easier to explain but it could be that simple.

It’s definitely easier to warm up beer in the South.

I think having plenty of yeast is also important. I can’t recall having had diacetyl issues since moving to 2.5 gallon batches. I over pitch almost all the time now since  I always pitch a whole pack of yeast for half a batch.

I also get all my beers into the mid 60’s in primary for a few days.

On the pitch rate, I remember hearing some things about pitching the proper amount and I think we have batted it around here before.  Some people say it's hard to overpitch at the homebrewer level but there was talk about the various phases that yeast goes through and how those phases create flavors that beer drinkers find pleasing.  If you pitch more yeast than you need then the yeast may not go through that phase and those flavors will not be produced.  That might be a fine point but I have been keeping it in mind and trying to dial in the proper amount of yeast to pitch.   

[denny]

If a higher temp near the end of fermentation (and after fermentation) has anything to do with it, location could be key.  A beer sitting on the floor in Texas (my son tells me that Texas doesn't have many basements) compared to a beer sitting on a concrete basement floor in Chicago in the winter could be as far as you need to look.  As mentioned... all spring and summer with 940 and Bayern... no diacetyl.  Now this fall with cooler temps and WLP001 and two beers with some diacetyl.  I'm not trying to make it easier to explain but it could be that simple.

Keep in mind it's not the temp itself, it's the effects of the temp.  Meaning anything you can do to keep the yeast active will reduce d.  Thats why krausening is so effective.

[denny]

If a higher temp near the end of fermentation (and after fermentation) has anything to do with it, location could be key.  A beer sitting on the floor in Texas (my son tells me that Texas doesn't have many basements) compared to a beer sitting on a concrete basement floor in Chicago in the winter could be as far as you need to look.  As mentioned... all spring and summer with 940 and Bayern... no diacetyl.  Now this fall with cooler temps and WLP001 and two beers with some diacetyl.  I'm not trying to make it easier to explain but it could be that simple.

It’s definitely easier to warm up beer in the South.

I think having plenty of yeast is also important. I can’t recall having had diacetyl issues since moving to 2.5 gallon batches. I over pitch almost all the time now since  I always pitch a whole pack of yeast for half a batch.

I also get all my beers into the mid 60’s in primary for a few days.

This is my mantra....if you pitch plenty of healthy, active yeast and give it time to work, you won't have diacetyl to deal with.

[hopfenundmalz]

My threshold for detecting diacetyl is quite low, meaning it's very easy to pick up, even in minute amounts. I think this is true of most educated beer drinkers.

Our beers have had a complete lack of this issue...maybe we are just lucky? I personally would dump the beer if this was detected. I do not like it. Not one bit.

It has as much, if not more, to do with physical differences as education and training.

To add to Denny's point, we all have different sensitivities for all of our senses. About 20% of the population is blind to Diacetyl, that is genetics, similar to about the same amount that say Cilantro tastes like soap. We all have different compounds we are sensitive to, or not.