Thursday, May 20, 2010

Using Dry Yeast

Have used mostly Wyeast smack packs until now and decided to test some dry yeast, mostly to keep some in stock and avoid a trip to the LHBS for every batch I brew, since I always like to get the freshest possible liqui yeast. Got the 11.5g dry yeast from Fermentis, Safale S-04, Safale US-05 and Safale S-33.
I must say I'm mostly not going back to liquid yeast, unless I need a special strain that I can't get in dry.
I got some cool direction on how to re-hydrate the dry yeast and it has worked for me every time, with Krausen formed after 6 to 8h.
The S-04 yeast is a beast, promoting a very fast and clean fermentation, not huge amounts of CO2 so no over spilling thru my airlock. The floculation after fermentation is awesome. The beer left is very clear and after few weeks in bottle conditioned, taste great!
The re-hydration process, which at first looked weird with the higher temperature, is listed below:
1)Once you have your wort ready to picth, at bout 70 to 75F, move to step 2
2)Boil 0.5l of tap water for 5min.
3)Remove from heat and cool to 103F
4)Add dry yeast and wisk to dissolve, for about 3min
5)Cool down further to pitching temp, 70 to 75F
6)Pitch to your wort

There are reasons behind not using sugar water or DME to re-hydrate the yeast, as well as for the high temperature. From what I read it has to do to the fact that the yeast cells do not have the hability to select what comes into the cell on the first seconds of re-hydration, so using sugar water would cause damage to the cells as good and bad thyings will get in. Also, once you get to step 5, the quick you pitch the better, so waiting to pitch actually works against you. The time from step 4 to picth should be about 5min.

So far, S-04 will be my primary yeast for general beers in substitution to Wyeast 1056. It promotes fully fermentation is 48h, has some bread taste while fermenting but it clears out within days.
The US-05 seems to produce fenolics that I don't like, so will probably stay away from it.
S-33 worked fine on my wit recipe and will mostly use it for wheat beers from now on.

1 comment:

  1. I came to the same conclusion about a year ago. I have to say that S-04 has become my favorite yeast. I don't even bother with rehydrating. I just sprinkle on top the oxygenated wort and it takes off in about 10-12 hours.

    I like your blog, especially the fermentation graphs.