Back to Shopping at NorthernBrewer.com

Yeast rehydration experiment

I never have “proofed” or rehydrated dry yeast before and never had a problem. Yesterday I brewed a 20 gallon batch of all Cascade IPA. Used 4 packets of Safale S-05 dry yeast. Two went into the 12 gallon conical and one each into 6.5 gallon glass carboys. In the attached photo the carboy on the left yeast was directly pitched from the packet. The one on the right I boiled some water with a small amount of sugar, cooled it to 95° and added a packet of yeast. Waited 20-30 min before pitching the rehydrated yeast. Everything was done with airlocks attached at about 1 p.m. The photo was this morning about 7:30 a.m. The OG was 1.080 (yes a big one) all aerated with an aquarium pump and diffuser. I tried to keep all procedures identical for the carboys.

Really not much difference between the two is there? I assume the brown “trail” in the krauzen of the direct pitched carboy is from the yeast laying on top there. I will keep an eye on them and report any big differences.

Definitely keep us posted!

Cool experiment. Why did you add sugar to the water prior to rehydrating the yeast? Never heard of anyone doing that.

yep you just threw a wrench in the experiment by adding sugar to the water. I have never seen those direction on any rehydrating specs before, but I may have missed something.

I hadn’t either until I searched for a how to and found John Palmer’s explantion. http://www.howtobrew.com/section1/chapter6-5.html
It wasn’t much water so I just scooped a 1/4 of a teaspoon or so and added it while boiling.

I had thought the primary function of “hydrating” dry yeast was exactly that: putting them in a situation without significant osmotic pressures, in order for the organisms to more easily hydrate their cell walls. I can’t imagine that a tiny amount of sugar added to that volume of water would present the kinds of osmotic pressures that’d be present in any normal (or high!) strength wort.

The sugar may expend some reserves, or it may stimulate the yeast; it could go either way, and is probably a small enough issue that the fundamental experiment is still going to produce interesting results. That said, any experiment bears repeating.

I hadn’t either until I searched for a how to and found John Palmer’s explantion. http://www.howtobrew.com/section1/chapter6-5.html
It wasn’t much water so I just scooped a 1/4 of a teaspoon or so and added it while boiling.[/quote]

I beleive you missed this?
“Note: Lallemand/Danstar does not recommend proofing after rehydration of their yeast because they have optimized their yeast’s nutrional reserves for quick starting in the main wort. Proofing expends some of those reserves.”

THis only lists 2 dry yeast companies, but I go by yeast manufacturers sites and have never heard of adding sugar

Would have been interesting to see this on much smaller beers …

Well, it looks to me that the direct pitch beer is further along in fermentation than the rehydrated beer. It also looks like there’s slightly less volume in the direct pitch carboy than the other.

Adding sugar (proofing) is a technique traditionally used by bakers with dry yeast to show that it is still viable. If you find a packet of dry yeast that has been collecting dust on your shelf for a couple of years, it is a good idea to proof it. It is maybe a better idea to throw it away. Fresh yeast that has been refrigerated or at least not exposed to elevated temperatures does not need proofing, although the small amount of sugar is unlikely to hurt anything either.

Brewers yeast has dates to use by, doubt most people are going to use old dry yeast

I see what Mark did was a plus. Glass half full than rather half empty. I can’t see a negative here by using the sugar, but if it’s a plus to help things possibly than that’s a good thing. I used to not bother with yeast nutrient in yrs past. But I read that it was a good thing for yeast health and a positive thing for it’s activity. So now I use it. I can’t say that it made a difference one way or another, but to me it’s one more positive maneuver and a help. It doesn’t really matter to me if someone thinks I’m spinning my wheels, I think it’s a plus and that makes me feel more confident.

We all know not to admit to reading directions. Never, ever admit it! But, had you read the directions on the web site you would notice there is no mention of adding sugar or extract in the rehydrating.

OH, NO! It sounds like I read the directions! NO! I didn’t read the directions! I know this because I heard it from a female brewer who readily admitted reading the directions.

I’ve read that starting a yeast with simple sugar acclimates them to the simple sugar and therefore reduces their ability (appetite for) malt sugars. It’s still a good experiment. Thanks for reporting.

How the article starts our is [quote]Preparing Dry Yeast
Dry yeast should be re-hydrated in water before pitching. Often the concentration of sugars in wort is high enough that the yeast can not draw enough water across the cell membranes to restart their metabolism. For best results, re-hydrate 2 packets of dry yeast in warm water (95-105°F) and then proof the yeast by adding some sugar to see if they are still alive after de-hydration and storage.[/quote]
I will admit getting ahead of myself adding the sugar first. Really didn’t read on after the first paragraph since it explained it well enough for me. The point of the thing was to see if rehydrating the yeast made a difference. All proofing does is check to see if the yeast is alive. Obviously it is and as of 4p.m. I see no advantage in rehydrating. So I kind of read the instructions, just didn’t realize there were more. Didn’t seem that complicated.

[quote=“HD4Mark”]How the article starts our is [quote]Preparing Dry Yeast
Dry yeast should be re-hydrated in water before pitching. Often the concentration of sugars in wort is high enough that the yeast can not draw enough water across the cell membranes to restart their metabolism. For best results, re-hydrate 2 packets of dry yeast in warm water (95-105°F) and then proof the yeast by adding some sugar to see if they are still alive after de-hydration and storage.[/quote]
I will admit getting ahead of myself adding the sugar first. Really didn’t read on after the first paragraph since it explained it well enough for me. The point of the thing was to see if rehydrating the yeast made a difference. All proofing does is check to see if the yeast is alive. Obviously it is and as of 4p.m. I see no advantage in rehydrating. So I kind of read the instructions, just didn’t realize there were more. Didn’t seem that complicated.[/quote]

You haven’t even tasted it yet, right, it is still fermenting? So how is there no advantage
In a bigger beer like this may hide a lot of flaws of rehydrating vs not.

On my few tests it paid to rehydrate. I tried it a few times on a simple light pale ale recipe. 1.050 gravity, 30 IBU.
You could tell the difference, not rehydrating was far more estery/fruity/phenolic rehydrating was much more clean. Certain beers some of those esters may not be detectable, or even help.
I will take the minute it takes to warm some water up and dump the packet in

I understand what you are saying. I meant that at 4 p.m. there appears to be no advantage so far. I have not quit on my little experiment. It is one of those steps I never thought necessary so maybe I could prove it to myself. Have to start using Nottingham yeast since Danstar says not to hydrate :roll:

[quote=“HD4Mark”][quote=“grainbelt”]

You haven’t even tasted it yet, right, it is still fermenting? So how is there no advantage
[/quote]
I understand what you are saying. I meant that at 4 p.m. there appears to be no advantage so far. I have not quit on my little experiment. It is one of those steps I never thought necessary so maybe I could prove it to myself. Have to start using Nottingham yeast since Danstar says not to hydrate :roll: [/quote]

I have never seen a dry yeast company say not to rehydrate on all of their instructions. But with the internet depends on where you are getting your instructions

I recall that one of the big dry yeast companies (I do not remember specifically which one) recommends sprinkling the yeast directly onto the wort and NOT to rehydrate. Wonder why they would say something like that if it would produce inferior results… I mean, they want to sell more product, right?!

Bad directions/ease of use.
Just like homebrew kit directions. Horrible. But they want to sell more right? Why do they suck so bad?

Why do dry yeast companies list, pitch it in for homebrewers and rehydrate for pros or look on their website and they say rehydrate.

Yep, it’s sorta counterintuitive that they would want your beer to taste like crap so you could blame their yeast, right?

I’ve not checked every dry yeast on the market, but all the product data sheets I’ve read - including all the Danstar yeasts - say to rehydrate.

The instructions provided by the kit packagers are minimal and not to be trusted. Apparently they are more afraid of discouraging new brewers with a bit of complexity than they are of discouraging new brewers with less-than-optimal beer. They probably are correct. Just throwing the yeast in the fermenter with a dirty shovel will still make beer, and a lot of us take the Homer Simpson approach to beer: “Yum! Beer!”

Fortunately, we’re all free to ignore the directions, experiment, and brew the way we prefer.

Back to Shopping at NorthernBrewer.com