Rehydrated yeast a bit early

[pilgrimhudd]

Hiya, I've had a Google search on this and most info I've found on us sites seem to suggest I should start again but thought I'd check on this site.

I brewed up a weizenbock last night, intending to pitch and stick the fv in the brew fridge. However it took an age to cool and I got tired and went to bed at 1am after putting the wort in the fv at about 40c.

I rehydrated the yeast at around 11pm, realised I wasnt going to pitch so chucked a tsp of sugar in and put in the fridge. It,s covered with cling film.

Anyway should I just ditch that and make up some new this morning? I think I know the answer already.

 

[PhilBrew]

Hi pilgrimhudd

If you've got more ready to go, probably best to use it and not rely on the cold stuff from the fridge ... but then if that Bock has a substantial OG, it probably wouldn't hurt to let the stuff in the fridge come up to temp (slowly) and pitch both the (freshly rehydrated) replacement and the original

Cheers, PhilB

 

[pilgrimhudd]

Cheers mate, I ditched the old stuff in the end and made up some fresh, waste of money but I suppose on balance I'd rather that than an infected brew.

 

[MrRook]

What yeast is it? The current consensus is that dry yeast doesn't need to be rehydrated.

 

[pilgrimhudd]

What yeast is it? The current consensus is that dry yeast doesn't need to be rehydrated.

Munich wheat yeast, danstar. Yeah i've heard that, though it seems to work for me and i've not heard the reasoning behind not rehydrating? Is it simply an infection risk?

 

[Chippy_Tea]

What yeast is it? The current consensus is that dry yeast doesn't need to be rehydrated.

It seems home brewers are split on the subject of re-hydration.

Benefits of dry yeast re-hydration
When you pitch a properly rehydrated yeast pack you reduce the probability of a number of problems that may occur as a result of underpitching, i.e., not putting enough yeast cells into the wort. Before we go further I should point out that proper pitching rate is only one variable a brewer needs to consider for a healthy fermentation. Other factors to consider include: ideal wort temperature (40-50°F for lagers, 60-70°F for most ales), ideal fermentation temperature (45-55°F for lagers, 60-75°F for most ales), proper wort oxygenation (minimum of 8 ppm), and nutrient availability (usually only a concern when a large number of adjuncts or simple sugars are used to produce wort). I digress though, back to the topic at hand. Rehydrating yeast allows brewers to pitch an adequate amount of healthy yeast into wort, ensuring full attenuation and reduction of off-flavors. An under-attenuated beer may taste bland, cloyingly sweet, or like malt extract. The two primary off-flavors stemming from underpitching include:

• Acetaldehyde-green apple
• DMS-cooked corn and/or vegetables

Both of these off-flavors usually fade over time, however, I find it easier to pitch the proper amount of yeast initially so I do not have to worry about off-flavors being present in my beer.

https://www.homebrewsupply.com/learn/do-i-need-to-re-hydrate-dry-yeast.html

 

[Drunkula]

Pitching cold yeast into wort at or below its fermenting temperature isn't a problem. It came up in a White Labs Q&A. The other way round can cause problems and premature flocculation, especially with that crybaby s-04.

 

[LeeH]

Pitching cold yeast into wort at or below its fermenting temperature isn't a problem. It came up in a White Labs Q&A. The other way round can cause problems and premature flocculation, especially with that crybaby s-04.

Fermentis disagrees with you.

 

[pilgrimhudd]

Premature flocculation is always bad.

 

[PhilBrew]

Hi Drunkula

Pitching cold yeast into wort at or below its fermenting temperature isn't a problem.

... erm, so why do their instructions for using their yeast describe the dangers of doing that ...

Directions for Use: Store in refrigerator until use, do not freeze. Remove 2 hours prior to addition and let warm to room temperature (~70°F). This makes re-suspension in the vial easier, and prevents a temperature shock when added to wort. Remove the shrink wrap on cap, shake the vial well to re-suspend yeast, and open cap carefully. ... link to original

... and Chris White write a whole section about "atemperating" the yeast to the wort temp in his "Yeast" book (co-authored with Jamil Zainisheff)

Hi Chippy/MrRook

What yeast is it? The current consensus is that dry yeast doesn't need to be rehydrated.

It seems home brewers are split on the subject of re-hydration.

... sorry, pedantic point, I know, but ... dried yeast can't bud (to reproduce) or take in sugars to ferment, they HAVE to be rehydrated to do the job brewers want them to do ... the debate is about what to rehydrate the yeast in/with

Cheers, PhilB

 

[MrRook]

I've had great success with these two directly pitched. The top one is K-97 that made a nice alt. The other is Munton's which is a highly underrated yeast.

 

[Drunkula]

... erm, so why do their instructions for using their yeast describe the dangers of doing that ...

No idea, it was one of their employees doing a Q&A about it saying it. I'll have a quick look to find it tomorrow as I can't remember if it was a podcast or video. She specifically said the one direction was fine.

 

[Drunkula]

The current consensus is that dry yeast doesn't need to be rehydrated.

Until I see more evidence along these lines showing it doesn't need to happen any more then I'm rehydrating:

https://bkyeast.wordpress.com/2013/03/13/more-on-yeast-rehydration/

 

[PhilBrew]

Hi @Drunkula, I think I could have believed it if the advice had been "Pitching cold yeast into wort at or below its fermenting temperature isn't a problem ... so long as the temperature of the yeast is no more than 5C different from that of the wort" ... and wondered whether the advice that was really being given was about how "chilling your wort and your yeast and allowing the ferment to raise to fermenting temp, is better than pitching warmer than fermenting temp and cooling"

Cheers, PhilB

 

[Llamaman]

She specifically said ... one direction was fine.

She probably liked the Spice Girls too. Clearly not someone whose judgment should be trusted.

 

[Drunkula]

Hi @Drunkula, I think I could have believed it if the advice had been "Pitching cold yeast into wort at or below its fermenting temperature isn't a problem

Absolutely could be. Jamil has said that loads of times on the Brewstrong podcast and even says it's preferential if the yeast will kick above the temp your system can respond to.