Yeast and Temperature Question

[WriterWriter]

Hey all,

Having looked over some cider recipes where no heating is required, I was wondering why it's necessary to heat wort to a certain temperature, but not say cider. What is it about wort that makes it different?

Actually, from making bread I had always assumed that yeast needed to be added to liquids at a certain temperature but now I'm not sure why that is.

-WW

 

[user 29674]

There are some compounds in the wort (DMS and others) that need to be boiled off, and the hops need to be boiled to isomerize them and extract the bitterness/aroma/flavor.

As for the yeast question, they're living creatures, so its really no different than why you or I prefer to work at a certain temperature. I don't think or move well when I'm cold and I'm irritable when I'm hot, so if you want me to work well, keep me at a happy temperature. There's also the same issue of too hot or too cold and you kill me...