Rehydradting Safale 04

Last week I brewed an IPA and pitched Safale 05 directly on top of the wort after aeration without re-hydrating the yeast. My OG was really high because I ended up with less wort than I predicted. It took about 2 1/2 days before fermentation kicked off. I was worried that the yeast was pitched at a too high of temperature, but it looks like everything is going to be fine.

I plan on making a Northern English Brown Ale tomorrow and plan on using Safale 04. I was wondering how much water I need to boil to rehydrate the yeast and at what temperature.

I was originally planing to make a starter from from liquid yeast two days ago, but the brewstore was closed. Rather than making the starter with less than 24hours before pitching I'm just going to use dry yeast. Plus I don't feel like paying 7 dollars for yeast I'm only going to use once. I would like to get into yeast harvesting, but I would like to get the proper jars and equipment before I start.

I remember reading somewhere that you don't want to boil water before rehydrating as the yeasties need the minerals or something in the non-boiled water.

Anyways, my method is to get my sink water hot and put 2 cups in a glass measuring cup. When the temp is around 90 degrees I put the yeast in and stir it up. Then let it sit for about 20 minutes while I'm cooling the wort. Aerate the wort then pitch.

Airlock usually starts bubbling in ~8-12 hours

Hope this helps.

The boild water is a t 212F ... although that probably wasn't what you were asking.

Rehydration temps are anywhere from about 90 to 105F. Aim for the 105 area. The yeast rehydrate best around there (ie more make it back to life). The yeast will come back at even 70 or 60, only you get less then at 105. Much above 105 will begin to kill yeast. When you pitch to the wort, make sure that the two are about the same temp (ie wort is about 70, then your yeast around 70 +/- a bit).

Also I think rehyration time is like 30 mins. Much more than that, and the yeast have consumed all their reserves of food and begin to lose some of their vitality.

Or do a starter.

In BYO there was an article about rehydrating and with side by side tests brews came out BETTER without rehydrating.

I've never hydrated dry yeast with no bad results . . . . just sayin. But that was before I made starters!

Grinder - that's a good point about rehydration. I usually follow the manufacturer's label. What I posted aboved is pretty much from 'Yeast' but I figure the manufacturer knows his yeast, so that's why I go with what they say. I don't remember what Safeale recomends.

We started out rehydryating dry, then switched to pitching straight and didnt really notice any differences in lag time or taste.

There are millions of factors to consider when using dry yeast.

You shouldn't oxygenate wort with dry yeast
You should rehydrate
Boil water first to kill bacteria
Don't use RO or distilled water as osmotic shock will lower viability

So many variables... so little time.

A lot of people get low viability by not rehydrating, but then oxygenate wort to get more growth out of the live cells, which stops them noticing negative results.

I ended up boiling 1 cup of water, which boiled down to about 2/3 cup, chilled it in an ice bath, then pitched the yeast at around 90 degrees. I let it sit for 15 minutes then gave it a quick stir. After another 10 minutes my wort was cool enough to pitch. I shook my wort for about 5 minutes nonstop then pitched the yeast.

After about 12 hours later I have airlock activity every 2 seconds. My last batch took over 48 hours to show signs of active fermentation. I'm not sure if re-hydrating the yeast helped this time, of if it's because I under-pitched my first batch which had a high gravity of 1.075.

I'm going to make one more brew with dry yeast and will probably rehydrate it again. After that I'm going to start using liquid yeast with a proper starter and will eventually harvest and grow my own yeast.

I'm happy that I have 2 batches fermenting away in the closest. My big IPA is down to 1.020 from 1.075 after about 3-4 days of fermentation. The airlock is still bubbling about every ten seconds and there's still a thick layer of foam on top of the brew. If it get down to 1.015 or 1.010 by Sunday I will be happy.

Thanks for the help guys, I thought I would give you an update on my brews.