Did I cold shock my yeast?

[Creamy]

Hey all,

I'm on my fourth batch of beer, first time posting here, and I'm wondering if you guys (and girls) can help me out...

So I brewed a batch two nights ago, Amber Ale extract recipe from Northern Brewer with Wyeast 1056 liquid yeast (didn't have time for a starter this time). I didn't get enough ice at the store so my wort wasn't cooling fast enough, but it got to be 11 pm and I had to go to bed so I ended up pitching around 78* (I know it was too high but, hey, I had work). Anyway, when I woke up 8 hours later it was still 78, so I wrapped the carboy in a wet towel, blasted the AC, and managed to get it down to around 72 by the time I got home from work. Morning #2 (about 36 hours after pitching), I moved the carboy to a water bath with a little bit ice, wrapped it in a wet t-shirt, and got it down to about 64-66, by the time I got home from work today.

From what I've read on here, the higher-than-ideal temp during the first 24-36 hrs probably didn't hurt the beer too much because the yeast wasn't in alcohol production stage yet, so it shouldn't have produced much off-flavors (phenols?). What I'm worried about now, though, is whether I shocked my yeast by dropping the temp so much.

It was a fairly gradual drop (78-72 from ~0-15 hrs, 72 from ~15-33 hrs, 72-65 from ~33-38 hrs), but it was still about 13 degrees overall, which I know is a lot. The yeast seems to be doing fine (still bubbling steadily at hour 48) but I'm wondering if the temp shock is going to produce off-flavors--or, worse, stall my yeast? I happen to have some more 1056 in the fridge; should I make a starter now in preparation for it stalling? Or should I just chill out and see how it goes?

P.S. I have a hydrometer but my wine thief is broke. Any tips on how to pull beer from a carboy without one?

Thanks for any advice you can give! Love this forum! :rockin:

Mike

 

[brandonhagen1]

It will be fine and try using a turkey baster just remember to sanitize it

 

[Pie_Man]

From what I've read on here, the higher-than-ideal temp during the first 24-36 hrs probably didn't hurt the beer too much because the yeast wasn't in alcohol production stage yet, so it shouldn't have produced much off-flavors (phenols?). What I'm worried about now, though, is whether I shocked my yeast by dropping the temp so much.

Phenols and esters are actually produced during the cell growth phase, which occurs mostly before the "alcohol production" stage (the phases in the yeast lifecycle overlap). Source: https://www.homebrewtalk.com/f13/yeast-life-cycle-43977/

Phenols are a flavor classication, and not all phenols are bad. Some phenols, like clove flavors, are desirable in certain beer styles, other phenols, like plastic and band-aid type flavors are undesirable.

Did you ruin your beer? Highly doubtful. Did you create some undesirable flavors? Possibly, the finished beer will ultimately determine that.

In general, it is much better to pitch on the colder side of the yeast's temp range. Pitching hot and working backwards confuses the yeast, possibly causing some yeast to go dormant prematurely while also increasing the conditions for underisable flavors.

 

[Creamy]

Thanks!

I got that thing about off-flavors not being produced in the first 24-36 hrs from Yooper's post here: https://www.homebrewtalk.com/f163/pitched-yeast-ale-around-78-degrees-421712/

Do you disagree, or was s/he talking about other off-flavors?

 

[Pie_Man]

Thanks!

I got that thing about off-flavors not being produced in the first 24-36 hrs from Yooper's post here: https://www.homebrewtalk.com/f163/pitched-yeast-ale-around-78-degrees-421712/

Do you disagree, or was s/he talking about other off-flavors?

I don't see Yooper on that post. She is quite knowledgable, so I won't disagree with her .

It's my understanding, that the majority of yeast derived flavors are created during the exponential growth phase. Here's an article from Chris White, the owner of White Labs, explaining such: http://www.brewgeeks.com/the-life-cycle-of-yeast.html.

Other off-flavors, those results from infections, would typically take longer to develop.

Simply put, fermentation temperature control is important. As a brewer, you make wort, the yeast make beer. It's your job to make a tasty wort and keep the yeast happy. That means proper pitching rates, oxygenation levels, and temperature control. If you don't have a dedicated fermentation chamber, I would recommend the low-tech swamp cooler method (which you did).

Getting back to your beer, it will likely be perfectly fine as you cooled it down from 78 degrees fairly quickly and got fermentation temperature under control within relatively short order. I would RDWHAHB.

 

[duboman]

In short, yes you shocked the yeast and by doing so you increased the lag time for this batch but the yeast will acclimate and get to work for you but it may take a bit if it hasn't already started up.

As for off flavors, it's certainly possible but it may not happen at all. Personally, I would lose sleep over it since there isn't much you can do about it. just let it ride, give it a chance to cleanup after FG and enjoy your beer!

 

[Creamy]

I don't see Yooper on that post. She is quite knowledgable, so I won't disagree with her .

Oops, it was aiptasia who said that:

"It's not going to matter a hill of beans if you pitched at 78f unless your yeast was +/- 10 degrees from that. Then, you might temperature shock your yeast a little bit. A little bit of warmth is actually just fine while the yeast is in it's aerobic reproductive phase for the first 24-36 hours.

What is going to matter is when the yeast burn up all of that oxygen and begin their anoxic alcohol producing phase. If the wort is too warm at this stage, you are going to get a lot of interesting esters and phenols produced by the yeast (some strains more than others, your mileage may vary). This is when it's important to control the fermentation temperature to prevent those clove, banana and funky off flavors the Belgians are loved for.

For example, I let my lagers sit at room temperature for a day or so after pitching because the warmth encourages rapid yeast cell growth during it's aerobic phase. There isn't much if any alcohol being produced at this time so there's little risk for potential off flavors in the final beer. However, after that time, my lagers go into my drop freezer where I can specifically control the temperature in the low 50's where the beer ferments for 4-6 weeks."

Sounds like you're basically saying the opposite: that almost all of the off-flavors are going to be produced in that 24-36 hrs exponential growth phase, yea?

Thanks for the link and to everyone everyone else who chimed in!

 

[Pie_Man]

Sounds like you're basically saying the opposite: that almost all of the off-flavors are going to be produced in that 24-36 hrs exponential growth phase, yea?

Thanks for the link and to everyone everyone else who chimed in!

I guess I am saying the opposite, but I am really just summaryzing information I have read from expert sources, like Chris White, who has a phd in this stuff and owns a yeast bank company. According to Chris White's lifecycle, the exponential growth phase has rapid cell growth and production of alchohol. This phase typically begins three to 15 hours after pitching yeast and lasts for one to four days.

Source: http://www.brewgeeks.com/the-life-cycle-of-yeast.html

 

[Queequeg]

I have a hydrometer but my wine thief is broke. Any tips on how to pull beer from a carboy without one?

I use a length of food grade tubing, sanitised and wear nitrile gloves also sanitized and put my thumb over the top.

 

[Creamy]

I use a length of food grade tubing, sanitised and wear nitrile gloves also sanitized and put my thumb over the top.

How did I not think of that? Brilliant!