Should I rehydrate EC-1118 or not bother? Pitching soon.

[kh54s10]

Just mixed up a Cru Select Pinot Grigio. The directions say to just sprinkle on the surface and close it up. The yeast package says to rehydrate. I have always sprinkled in wines in the past with pretty good success. I had one 3 gallon kit come out bad. I forget which kit, it was a red wine.

What is the current opinion? Rehydrate or no.

 

[RPh_Guy]

Proper hydration is always best
Use tap water, and GoFerm if you have it.

Boil the water (10x the weight of yeast, 5g yeast needs 50mL water) and cool to 95-105°F and add the yeast. Gently stir to break up clumps. Leave it sit for 15 mins and then begin tempering every 5 minutes by adding small amounts of must. You don't want to drop the temperature more than 10°F at once.

Cheers

 

[kh54s10]

Guess I will do as the yeast lab suggests and see if I can tell the difference.

 

[beernutz]

I've never rehydrated in 10 kits over the last 5+ years and also never had a bad batch. I believe every kit instruction I've followed has said to sprinkle the yeast so I vote for simplicity and one less opportunity for infection.

 

[kh54s10]

I've never rehydrated in 10 kits over the last 5+ years and also never had a bad batch. I believe every kit instruction I've followed has said to sprinkle the yeast so I vote for simplicity and one less opportunity for infection.

Too late!
I also have just sprinkled in the past. But with beer I have fairly religiously rehydrated. No infections...
I am not worried about doing the hydration, I was wondering how many rehydrate. I know that at least one dry yeast lab now recommends that you do not rehydrate their yeasts.

We'll see if it makes any difference.

 

[beernutz]

Too late!
I also have just sprinkled in the past. But with beer I have fairly religiously rehydrated. No infections...
I am not worried about doing the hydration, I was wondering how many rehydrate. I know that at least one dry yeast lab now recommends that you do not rehydrate . their yeasts.

We'll see if it makes any difference.

I'm sure it will be fine too. I have done dry beer yeast both ways and not noticed a difference.
FWIW, this video suggests, based on some insider knowledge, that a major dry yeast manufacturer is going to stop recommending rehydration.

 

[jgmillr1]

What is the current opinion? Rehydrate or no

Yeast manufacturers offer detailed rehydration instructions like the ones found here, so I would tend to follow their suggestion. The first sentence of these instructions is "Proper yeast rehydration is one of the most important steps to help ensure a strong and healthy fermentation."

Sure you can sprinkle yeast on your batch of wine and hope it rehydrates fine, but when you're already out $xxxx.xx on the grapes/juice then what's another 20min to be sure it ferments well?

 

[kh54s10]

Yeast manufacturers offer detailed rehydration instructions like the ones found here, so I would tend to follow their suggestion. The first sentence of these instructions is "Proper yeast rehydration is one of the most important steps to help ensure a strong and healthy fermentation."

Sure you can sprinkle yeast on your batch of wine and hope it rehydrates fine, but when you're already out $xxxx.xx on the grapes/juice then what's another 20min to be sure it ferments well?

As I said, the instructions said one thing, the yeast pack said another and as linked above. One dry yeast lab is now recommending that you do not rehydrate. So I was looking for what is current in the winemaking end of things. I did rehydrate and it is fermenting now.

 

[ellijayman]

Never have rehydrated any of Lalvin yeast and only one time had to double pitch after a week but works without rehydrating.

 

[RPh_Guy]

Multiple experiments show that proper rehydration increases cell viability drastically... Sprinkling may kill 50-90% of the cells vs rehydrating.

Underpitching undoubtedly "works", but may not generally be best.

Similarly, the liquid yeast manufacturers say you can direct pitch their yeast (and you certainly can), but a large body of evidence and experience says it's generally better to make starters to increase cell count.

How much better? That's difficult to say; Pitch rate is just part of the picture and YMMV based on a combination of factors.

Regards

 

[kh54s10]

Never have rehydrated any of Lalvin yeast and only one time had to double pitch after a week but works without rehydrating.

I know this. If you read my posts it said that I have always pitched dry. I was trying to see if there is new opinion.

Multiple experiments show that proper rehydration increases cell viability drastically... Sprinkling may kill 50-90% of the cells vs rehydrating.

Underpitching undoubtedly "works", but may not generally be best.

Similarly, the liquid yeast manufacturers say you can direct pitch their yeast (and you certainly can), but a large body of evidence and experience says it's generally better to make starters to increase cell count.

How much better? That's difficult to say; Pitch rate is just part of the picture and YMMV based on a combination of factors.

Regards

I have always read this and followed that rehydrating and starters were optimum and starters, necessary with all but low OG brews.
I also noted that at least one dry yeast manufacturer is now recommending based on studies that it is better to NOT REHYDRATE. Thus my question.

Though sprinkling may kill up to 50% it is highly unlikely that you would kill anywhere near 90%. It that were the case there would be millions of threads "my brew is not fermenting"

 

[RPh_Guy]

it is highly unlikely that you would kill anywhere near 90%.

Well, here are some experimental results:
https://bkyeast.wordpress.com/2013/03/13/more-on-yeast-rehydration/

Not sure who says to not rehydrate, but maybe they've made progress with their manufacturing/drying process (and do they supply viability rates?).
I wouldn't apply this across all dry yeast.

 

[beernutz]

https://drive.google.com/file/d/0BzNmUGsHZf7dOTZzZF9aQVluZXM/view

Here's an experiment which shows only minimal differences in viability between hydrated and non-hydrated dry yeast.

 

[RPh_Guy]

https://drive.google.com/file/d/0BzNmUGsHZf7dOTZzZF9aQVluZXM/view

Here's an experiment which shows only minimal differences in viability between hydrated and non-hydrated dry yeast.

Interesting, thanks!
Differing conclusions makes me wonder if yeast from different manufactures respond differently to being direct pitched.
There was an older experiment I saw that also demonstrated 50% relative loss by direct pitching but I can't remember what yeast was used.

I wish we had more data. Maybe some day I'll get a microscope and figure this out myself.

 

[beernutz]

Interesting, thanks!
Differing conclusions makes me wonder if yeast from different manufactures respond differently to being direct pitched.
There was an older experiment I saw that also demonstrated 50% relative loss by direct pitching but I can't remember what yeast was used.

I wish we had more data. Maybe some day I'll get a microscope and figure this out myself.

You're welcome. I agree that the devil must be in the details to explain the wide variance in experimental results and user experiences regarding rehydration. In my own case I've both rehydrated and also just sprinkled at various times without seeing much difference in lag times, attenuation, or the resulting beer for the same dry yeast. I guess that ambiguity is part of what keeps this hobby interesting.