wort temp when pitching yeast

[lonerhino]

I'm a new brewer and when my batch of beer didn't start fermenting after I pitched the yeast, one of the troubleshooting remedies was that the wort was too cool to activate the yeast ( under 70F ). if this is the case, then why do so many recipes say to cool the wort to 55 - 60 degrees and then add the yeast?
shouldn't I be adding the yeast to a mixture at around 100 degrees, like I do for baking bread?

 

[DarthCitra]

Pitch around 68-72 degrees. I dont know where you got your recipe from or what yeast you're using but, sounds a bit low and 100 is too high!

 

[pointcity-homebrew]

How, long has it been since you pitched? I usually pitch my yeast when I have cooled my wort down to around 65-68 and have had no issues.

 

[k1ngl1ves]

I always pitch at the bottom of the yeasts temp scale. Usually around 60°- 64°(depending on the yeast). Imo, pitching low is better than trying to fight the temp down later or risking some nasty off flavors.


Patience. Sometimes yeast take a bit to start showing some activity.

 

[lotusworker]

I would look on the back of the package of yeast. It will have the temperature range of that particular yeast. Most ale yeast are somewhere in the range of 60-75 degrees Fahrenheit. Lager yeasts have a much lower temperature, usually somewhere around 55.

Do you know what kind of yeast you used? You can always look it up if you tossed the package to be certain.

 

[BigFloyd]

In styles where a "clean" fermentation (not lots of yeasty character) is a good thing, the better practice is to:

-take a look at the optimal temp range for the particular yeast you're using

-chill the wort to a few degrees below the low end of that range

-pitch and let it rise on its own to the lower end of the optimal range. Keep it there until the krausen falls (about the same time airlock activity, if your seal is good, slows down).

-over a few days' time, let the temp come up towards the upper end of optimal and keep it there until finished.

For example, I'll pitch rehydrated S-04 at 60-61*F, let it come up to 63-64*F and hold it there during active ferment. Once it slows, it gets warmed up to 68-70*F to finish.

Yeast pitched into wort that's too warm can cause flavor issues. The yeast tend to get active more quickly and vigorously in the warmer wort. That produces its own heat which then makes it harder to cool down to the target temp. After a certain point, cooling it down a bit too much or too fast can cause the yeast to drop out and go nighty-night. Pitching cooler avoids these sorts of problems.

 

[Puddlethumper]

when my batch of beer didn't start fermenting after I pitched the yeast, ?

How do you know it didn't start fermenting? Airlock activity is not a very good indicator of yeast activity. As others have said, some yeast varieties take a little longer to start and, from my experience, some show a lot more airlock activity than others.

One clue about fermentation is the development of a krausen layer on your fermenting beer. But the only sure-fire way to know if fermentation is taking place is to take a hydrometer reading and compare it to an earlier reading. If the specific gravity is dropping then fermentation is happening.