Reduce Conditioning Time

[fuzzy2133]

I brew extract with specialty grains (full volume boil) and have temperature control (SOFC). How can I reduce the time needed to condition the green apple taste down to a minimum?

My fastest time is 1 month both bottle priming and kegging. This last batch Nierra Sevada is just about 2 months in bottle (I kegged 1/2 and it was 1 month conditioning time). The room I used for bottle carbonating got really hot (80F) this time.

Process:
Brew; taste is fine using both spring water and my tap water
Ferment at 64F-68F (set and don't change it) ~3 weeks until stable FG
Bottle prime/carbonate at room temp (70-75) 2-3 weeks and then keep in fridge 40F-35F (sorry no basement or cellar temp area) to age. When kegged I used the set it and forget method in the fridge.

I would rather not start making changes blindly.

Thanks for any help and input.

 

[duboman]

How are you handling your yeast? Starters? Pitch rate? Pitch temp?

Stressed yeast is more prone to produce acetaldehyde. The better you treat your yeast the less chances there are of developing those off flavors.

 

[twistr25]

You also boil with the lid off, right?

 

[pfgonzo]

You shouldn't be getting green apple taste at all if you're pitching the right amount of healthy yeast and keeping fermentation temps low. Chris White (White Labs) did an experiment for his book, Yeast, in which he fermented identical worts, one at 68F and another at 75F. The one at 75F produced something like 10x the amount of acetaldehyde. While conditioning will reduce some, it won't get rid of it all.

What temp do you usually ferment at? Try dropping it a few degrees and see if your green apple disappears.

 

[fuzzy2133]

How are you handling your yeast? Starters? Pitch rate? Pitch temp?

Stressed yeast is more prone to produce acetaldehyde. The better you treat your yeast the less chances there are of developing those off flavors.

My last 5 gallon batch I referenced above is my first time using the pitching calculator Mr. Malty, a stir plate and the starter. The starter I used was 24hrs old. Do the yeast more need time to grow and how close does the temperature between the starter & wort need to be?

You also boil with the lid off, right?

I only put the lid on when I steeped my aroma hop addition for 20min at flame out. Could this be a problem too?

You shouldn't be getting green apple taste at all if you're pitching the right amount of healthy yeast and keeping fermentation temps low. Chris White (White Labs) did an experiment for his book, Yeast, in which he fermented identical worts, one at 68F and another at 75F. The one at 75F produced something like 10x the amount of acetaldehyde. While conditioning will reduce some, it won't get rid of it all.

What temp do you usually ferment at? Try dropping it a few degrees and see if your green apple disappears.

Forgot to mention this was made with San Diego Super Yeast from White Labs.

64-66 according to the fermometer. I followed White Labs direction on the vial of 68F till fermentation starts and then adjust the temp. The first 16hrs were at 68-70F then dialed down to 64-66F.

Would those directions not apply to a starter?

 

[duboman]

Temperature should not be an issue with the starter.

Keep in mind it is better to pitch cold and allow the beer to self rise to the desired temperature, not the other way around.

Not sure why the recommendation would have been to go high and then drop.

Most likely the warmer fermentation is the culprit. Next time pitch a few degrees colder than desired and allow to rise slowly and there should be improvement.

 

[chickypad]

Most likely the warmer fermentation is the culprit. Next time pitch a few degrees colder than desired and allow to rise slowly and there should be improvement.

I agree, 16 hrs could be significant. I think they make the recommendation to pitch hotter similar to some who recommend pitching a lager at ale temps - to ensure the fermentation gets going. If you pitch enough healthy yeast you should not need to pitch hot.
Also, I like to decant starters and pitch just the yeast (have you ever tasted that nasty starter wort?). I let them go 24-30 hrs then chill for 24 to get the yeast to settle out.

 

[pfgonzo]

I think your temps were fine. I disagree with people above saying 68-70 leaves noticeable acetaldehyde after a normal fermentation.

There's been a movement (almost a competition) lately among homebrewers to lower and lower their fermentation temps. Some people are doing ales in the high 50s now and swearing by it, but I'm not one of them. Ales do just fine at 68. Most do just fine at 70, with no off flavors (depending on yeast strain).

Even at 70F, the highest temp you mentioned, you should not be getting noticeable acetaldehyde after 2 weeks in the fermenter of a normal gravity brew. My next thought is your starter process. Are you decanting the liquid and just pitching yeast, or are you pitching the entire starter volume? Can you detail your starter process?

[Edit] One caveat: How do you know your ferm temps? How are you measuring them, and how are you keeping the temps controlled?

 

[billl]

Acetaldehyde is produced during the initial growth phase of the yeast. If you are getting a noticeable amount, that means something is amiss in that stage. Since you are controlling temps fairly well, the next places to look would be the amount of yeast you are pitching and how well you are aerating.

 

[chickypad]

I was referring specifically to that WL strain, as well as 001. WL publishes the optimum temps for those as 68-73 which IME are too high. I get fruit and diacetyl at those temps, and much cleaner ales at 63-65. Since I'm usually making hoppy pales and IPA's with those strains I like to be drinking them very young. YRMV.

 

[duboman]

I think your temps were fine. I disagree with people above saying 68-70 leaves noticeable acetaldehyde after a normal fermentation.

There's been a movement (almost a competition) lately among homebrewers to lower and lower their fermentation temps. Some people are doing ales in the high 50s now and swearing by it, but I'm not one of them. Ales do just fine at 68. Most do just fine at 70, with no off flavors (depending on yeast strain).

Even at 70F, the highest temp you mentioned, you should not be getting noticeable acetaldehyde after 2 weeks in the fermenter of a normal gravity brew. My next thought is your starter process. Are you decanting the liquid and just pitching yeast, or are you pitching the entire starter volume? Can you detail your starter process?

[Edit] One caveat: How do you know your ferm temps? How are you measuring them, and how are you keeping the temps controlled?

I'm with chickypad and I think you may have misunderstood.

We are not talking specifically about the actual fermentation temp but the pitching temp itself, as well as being a healthy starter and decanting.

IME and discussed in the book "Yeast" it is beneficial for the il yeast to be pitched on the cold end and allowed to rise, not the reverse, especially 16 hours later when active fermentation could be well under way.

All yeast have a desirable range but there are taste thresholds associated with the highs and lows. I prefer the lower end for the cleaner tastes while others I know prefer higher temps, to each their own, but when speaking about yeast health and proper fermentation techniques to prevent stress pitching warm and then cooling is not the way to go about it.

Again ymmv....

 

[tgmartin000]

Starter temp should be within 10 degrees of wort temp at pitching. As others said, pitch a little low, free rise to your desired ferment temp, hold there till fermentation is nearly done, then let free rise to 68-70. HOld for a few days. Crash and rack to your serving vessel.

Also proper O2 levels are really important, and obviously pitching the proper amount of healthy yeast.

Although I don't have hard data, yeast nutrients could also help.

 

[fuzzy2133]

I think your temps were fine. I disagree with people above saying 68-70 leaves noticeable acetaldehyde after a normal fermentation.

There's been a movement (almost a competition) lately among homebrewers to lower and lower their fermentation temps. Some people are doing ales in the high 50s now and swearing by it, but I'm not one of them. Ales do just fine at 68. Most do just fine at 70, with no off flavors (depending on yeast strain).

Even at 70F, the highest temp you mentioned, you should not be getting noticeable acetaldehyde after 2 weeks in the fermenter of a normal gravity brew. My next thought is your starter process. Are you decanting the liquid and just pitching yeast, or are you pitching the entire starter volume? Can you detail your starter process?

[Edit] One caveat: How do you know your ferm temps? How are you measuring them, and how are you keeping the temps controlled?

I made an SOFC, a bit of a bastard with an STC1000 in control of the fan and brew belt (when needed). The probe is insulated from the air temp and I have a fermometer on the better bottle. Just realized I did not check the probe calibration. If the STC readout matched the fermometer strip would that be close enough?

For the starter I used Mr. Malty's DME recommendation for 1 liter. Heated the water to help dissolve the DME then boiled 15 min. Cooled to 68-70(? can't remember exact temp low enough to be safe for the yeast) topped off, shook flask to aerate and pitched yeast. Placed on stir plate (yes sanitized stir bar) and let it run 3/4 power. Never got a big vortex like some I have seen posted on this site just a small one. The stir bar is small like a 1,000mg vitamin capsule. I think the room temp where the starter was ran a consistent 75F.

I did not decant the starter had about a 2 day lead when I got the OK to brew. The starter was just over 25hrs old. The whole liter, liquid and all went in (except for the stir bar caught that with a computer magnet against the flask.

Acetaldehyde is produced during the initial growth phase of the yeast. If you are getting a noticeable amount, that means something is amiss in that stage. Since you are controlling temps fairly well, the next places to look would be the amount of yeast you are pitching and how well you are aerating.

My aeration is shake the crap out of the better bottle for 30-45 seconds take a 10 second break and repeat 1 or 2 more times.

The temp difference when I pitched the yeast was within 10 degrees. This is all assuming Mr. Malty is accurate. Some one mentioned yeast nutrient. I was making this to be low ABV 3.5%-4.5%. Is there a guide line for when to add it?

 

[duboman]

I made an SOFC, a bit of a bastard with an STC1000 in control of the fan and brew belt (when needed). The probe is insulated from the air temp and I have a fermometer on the better bottle. Just realized I did not check the probe calibration. If the STC readout matched the fermometer strip would that be close enough?

For the starter I used Mr. Malty's DME recommendation for 1 liter. Heated the water to help dissolve the DME then boiled 15 min. Cooled to 68-70(? can't remember exact temp low enough to be safe for the yeast) topped off, shook flask to aerate and pitched yeast. Placed on stir plate (yes sanitized stir bar) and let it run 3/4 power. Never got a big vortex like some I have seen posted on this site just a small one. The stir bar is small like a 1,000mg vitamin capsule. I think the room temp where the starter was ran a consistent 75F.

I did not decant the starter had about a 2 day lead when I got the OK to brew. The starter was just over 25hrs old. The whole liter, liquid and all went in (except for the stir bar caught that with a computer magnet against the flask.



My aeration is shake the crap out of the better bottle for 30-45 seconds take a 10 second break and repeat 1 or 2 more times.

The temp difference when I pitched the yeast was within 10 degrees. This is all assuming Mr. Malty is accurate. Some one mentioned yeast nutrient. I was making this to be low ABV 3.5%-4.5%. Is there a guide line for when to add it?

I use 1/4 tsp nutrient in my starters and 1/2 tsp in my boil at the last 10 minutes.

Process seems fine. As for the pitching temp, it is really about the wort, not the starter itself. I get my wort down to 60, pull my starter out of the fridge, decant and pitch the cold starter right into the wort, probably a 20 degree difference or so. Most, if not all my fermentations are visible within 8 hours as the temp rises to my desired fermentation temperature.

As for pitch rate I only use http://www.yeastcalc.com and select Kai's stir plate option. He has done some extensive work in calculating yeast growth for continuously stirred starters that Chris and Jamil have not documented in their studies. Kai's research is documented on the yeast calc site.

 

[billl]

"My aeration is shake the crap out of the better bottle for 30-45 seconds take a 10 second break and repeat 1 or 2 more times."

You are almost certainly under-aerating. If you are only doing 30 second burst of shaking, you probably want to do that a bunch of times. You need about 5 minutes of shaking to get near saturation levels. Personally, I found that to be a PITA, so I got a cheap aquarium pump. Toss it in for 15-20 minutes while you clean up and you'll be ready to pitch.

If you fix that and make sure your wort is down to fermenting temps before you pitch the yeast, I think you'll see a big improvement.

 

[twistr25]

I've never had aeration trouble quickly dumping my wort into my primary bucket. Guess it depends on how much space you have in the better bottle though to get air down into it.

 

[tgmartin000]

Aeration alone will never really get you the proper O2 levels. Pure O2 is the way to go!

I use the O2 kit from Williams brewing and love it. No lifting, no shaking, nothing.

 

[jbaysurfer]

I think your temps were fine. I disagree with people above saying 68-70 leaves noticeable acetaldehyde after a normal fermentation.

There's been a movement (almost a competition) lately among homebrewers to lower and lower their fermentation temps. Some people are doing ales in the high 50s now and swearing by it, but I'm not one of them. Ales do just fine at 68. Most do just fine at 70, with no off flavors (depending on yeast strain).

Even at 70F, the highest temp you mentioned, you should not be getting noticeable acetaldehyde after 2 weeks in the fermenter of a normal gravity brew. My next thought is your starter process. Are you decanting the liquid and just pitching yeast, or are you pitching the entire starter volume? Can you detail your starter process?

[Edit] One caveat: How do you know your ferm temps? How are you measuring them, and how are you keeping the temps controlled?

I don't think it's a competition, it's just homebrewers experimenting like they always do. Also, some of them, like me, have probably had some success at fermenting on the cool side of the range.

 

[billl]

"Aeration alone will never really get you the proper O2 levels. Pure O2 is the way to go!"

That isn't true. You can easily reach o2 saturation levels with shaking or an aquarium pump.

 

[Yooper]

I followed White Labs direction on the vial of 68F till fermentation starts and then adjust the temp. The first 16hrs were at 68-70F then dialed down to 64-66F.

Would those directions not apply to a starter?

This is the exact opposite of the way to get best flavor. Oh, sure, I know the vial says that, but that's to compensate for underpitching. If you pitch the proper amount of yeast, you always will get a better result pitching cooler and letting the temperature rise.

For example, take your starter out of the fridge when you finish brewing and start chilling. Chill the wort to 62 degrees, and decant the starter and pitch the yeast into it. Generally, the yeast will be about 58-60 by then, and pitching it into slightly warmer wort really works well. Then, let the temperature rise to the preferred fermentation temperature. For me, that's often 66 degrees. Hold it there until the bulk of fermentation is done, and then you can let it rise up to 68-70 then if you want to.


If you want a drinkable beer sooner, the key is to prevent off flavors in the first place that need to "clean up". I am routinely drinking beers at 14-21 days old, depending on the type (most often APAs and IPAs). Good water chemistry, proper yeast pitching rate, and proper fermentation temperature management are the keys to getting there. If there aren't any off-flavors to condition out, then you've got the process down!

 

[pfgonzo]

I don't think it's a competition, it's just homebrewers experimenting like they always do. Also, some of them, like me, have probably had some success at fermenting on the cool side of the range.

Not trying to start a war, I promise.

Experimentation is one thing, but I'm seeing more and more brewers telling new hobbiests that they must ferment their ales at 62 (or less) or they'll end up with terrible off flavors and fusel alcohols and it simply isn't true. I'm all for experimentation and getting the right flavor profile for your beer. Some people prefer super clean, while others enjoy the esters of a 75F fermentation.

After reading Chris White's book, Yeast, and his experiment with fermentation temps and acetaldehyde production, I don't know that I'd fret over a 68-70F temp the way others might. Highly recommended read for any brewers that haven't done so.

 

[fuzzy2133]

"Aeration alone will never really get you the proper O2 levels. Pure O2 is the way to go!"

That isn't true. You can easily reach o2 saturation levels with shaking or an aquarium pump.

The only difference between pure O2 and Shaking/aquarium pump is pure O2 will get you above 8ppm. That is the general census from the people at the yeast banks.

This is the exact opposite of the way to get best flavor. Oh, sure, I know the vial says that, but that's to compensate for underpitching. If you pitch the proper amount of yeast, you always will get a better result pitching cooler and letting the temperature rise.

For example, take your starter out of the fridge when you finish brewing and start chilling. Chill the wort to 62 degrees, and decant the starter and pitch the yeast into it. Generally, the yeast will be about 58-60 by then, and pitching it into slightly warmer wort really works well. Then, let the temperature rise to the preferred fermentation temperature. For me, that's often 66 degrees. Hold it there until the bulk of fermentation is done, and then you can let it rise up to 68-70 then if you want to.


If you want a drinkable beer sooner, the key is to prevent off flavors in the first place that need to "clean up". I am routinely drinking beers at 14-21 days old, depending on the type (most often APAs and IPAs). Good water chemistry, proper yeast pitching rate, and proper fermentation temperature management are the keys to getting there. If there aren't any off-flavors to condition out, then you've got the process down!

Yes the more I read responses and thought about it I realized the vial instructions do not apply with a starter.

What is a good gravity for the starter? I have read some people making a starter with the projected wort gravity.

Also how long can a starter be kept in the fridge? Life can be a pain and change plans last minute.

 

[jbaysurfer]

Not trying to start a war, I promise.

Experimentation is one thing, but I'm seeing more and more brewers telling new hobbiests that they must ferment their ales at 62 (or less) or they'll end up with terrible off flavors and fusel alcohols and it simply isn't true. I'm all for experimentation and getting the right flavor profile for your beer. Some people prefer super clean, while others enjoy the esters of a 75F fermentation.

After reading Chris White's book, Yeast, and his experiment with fermentation temps and acetaldehyde production, I don't know that I'd fret over a 68-70F temp the way others might. Highly recommended read for any brewers that haven't done so.

You wouldn't have an opponent anyway

I automatically suspect any brewer who tells another they "must" do something. There are too many right ways to do it.

As far as the difference between 68-70, I wouldn't nitpick. But there's a substantial difference between 64 and 68 with most ale yeasts IME.

It's not at all that I think 68 is "wrong". I just like my ales on the cleaner side, with very little ester production, so that's why I ferment at 64. I pitch at 62 and let it rise to 64 where I hold it for at least 3 days, then I actually DO step it up 2 degrees a day until I hit 72. I consider it a diacetyl rest, but I find it helps my bigger beers finish out.

 

[jbaysurfer]

The only difference between pure O2 and Shaking/aquarium pump is pure O2 will get you above 8ppm. That is the general census from the people at the yeast banks.



Yes the more I read responses and thought about it I realized the vial instructions do not apply with a starter.

What is a good gravity for the starter? I have read some people making a starter with the projected wort gravity.

Also how long can a starter be kept in the fridge? Life can be a pain and change plans last minute.

Good gravity for a starter is 1.040. 1 cup of DME for 1 Liter puts you right there.

I wouldn't keep a starter in the fridge for more then a week. I'm sure someone will have a different opinion on this! The cleaner you are when you make it, and the better you seal it up from the outside environment when refrigerating it the longer it'll last.

All IME.

 

[duboman]

Good gravity for a starter is 1.040. 1 cup of DME for 1 Liter puts you right there.

I wouldn't keep a starter in the fridge for more then a week. I'm sure someone will have a different opinion on this! The cleaner you are when you make it, and the better you seal it up from the outside environment when refrigerating it the longer it'll last.

All IME.

The only thing ill add to this and the good advice already given is weigh out the priming sugar.

 

[fuzzy2133]

When should the yeast nutrient be put in the starter?

 

[duboman]

When should the yeast nutrient be put in the starter?

Before it starts to boil. You can just add it with the DME as you mix in the water. If you add it during the boil it will cause a volcano.

 

[fuzzy2133]

I am so glad I asked. A volcano in the kitchen would end my ability to brew anything inside.