Rehydrate or Not?

Ingredients
1

That is the question.

This is my first time brewing. Everthying I’ve read says you should rehydrate the yeast, including the instructions on the back of the Lallemand Nottingham yeast package that came with the beer kit.

However the instructions with the Brewers Best kit I’m using specifically say “Sprinkle the contents of the yeast sachet on top of the entire wort surface (DO NOT REHYDRATE)”

So why would they say not to rehydrate?

My homebrew store says it doesn’t really make a difference.

Thanks!
Andre

2

It doesn’t add any extra time to the day or hurt so it’s dealers choice. Although the argument can be made that you lose a certain percentage of the cells if you don’t.

3

At the start of the day I throw a bit of water in the microwave with a syranwrap cover and let it boil. I leave it there until I am ready to rehydrate and pitch. Adds zero time and a teensy bit of effort.

4

Thanks guys, I haven’t decided which I’m going to do, I may just sprinkle since (being my first time) I’m not sure how long it’ll take to cool the wort to 70 deg.

5

What does that matter? Get you rehydration water sanitized, chill wort to temp, rehydrate, pitch. My results when I sprinkle are fine, but I believe in rehydration.

6

Fact: By pitching dry yeast straight on top of wort, about half the yeast immediately die.

Fact: Dead yeast make great “yeast nutrients”.

Fact: An 11-gram yeast packet contains about double the yeast you need for a 5-gallon batch.

Conclusion: It just doesn’t really matter that much.

Personally, I think most people tend to overpitch with dry yeast for these same reasons, leading to beer that’s more clean and bland than intended.

7

I just brewed a German pils using 34/70.  I followed the manufacturer’s directions and sprinkled it on the wort without rehydrating.

8

I use 34/70 or S-189 on all my lagers (including my last batch: imperial pilsner) by sprinkling on the wort without rehydrating and make some pretty good lagers.

9

I still say that the instructions on rehydrating yeast in warm water that some sources have, are incorrect. I believe that the use of warm water invites the possibility of overheating the yeast and killing or injuring it.  If I rehydrate, its only in room-temp water.

The regards to rehydration, there are plenty of scientific trials that show that rehydrating improves the viability of yeast. However, improved viability doesn’t mean that will make a meaningful difference to your finished beer. It seems to make little difference based on my experience, but I do rehydrate when I have the chance.

10

If the manufacturer recommends rehydrating, I at least consider it…I my not do it, but I consider it!  The 34/70 said nothing on the pack but “sprinkle on wort” so that’s what I did.

11

The process of rehydrating yeast in warm water also has made me dubious of the method.  I quit rehydrating all dry yeast a few years ago, and haven’t noticed any difference in lag times or final attenuation.

12

Ok, I did end up rehydrating. Thanks for all the advice. I was concerned that if I started it too early I’d be over the recommended 30 mins by the time the wort hit 70 (I guess I was overthinking it a little).

I followed Stevie’s advice and heated the water in the microwave.  Then when I was ready to rehydrate added bottled water to drop temp to range on package. The yeast was nice and fluffy after 15 mins.

Now with my first batch in the fermenter I feel that I’ve learned a lot. Now I just need to learn the Art of Patience!!

AA

13

I’ve rehydrated and sprinkled dry. The only difference, albeit anecdotal because I’ve not used a stop watch, is that I believe I detect a shorter lag time with rehydrated. Both methods made great beer.