Dry yeast re-hydration

Hi All!
I,m planning a brew for this weekend and I,m going to be re-hydrating dry yeast. In Palmers “How to Brew” he says he has placed the water and yeast in ziplock baggies,expelled the air and re-hydrated this way.My question is should I spray a little star-san inside the baggies first? He makes no mention of it in the book. just wondering… :cheers: Tankie

Yes sanitize the bag take no chance on any kind of infection. Bettter safe than sorry.I use a mason jar for both starters and hydration works great.

It is a best practice to not let the rehydrated yeast sit for more than 30 minutes before pitching. The yeast cells will be in a weakened condition, having used up their reserves, if not pitched into a wort.

http://www.brewwithfermentis.com/tips-t ... hydration/

No need to sanitize the baggies - they’re sanitary out of the box. Same with aluminum foil off the roll.

I also use a mason jar, I’m sure I would end up spilling a ziplock bag

Yep. And paper towels, too.

How many people who rehydrate their yeast actually boil the water? I ask because when I used to brew extract I never brewed my top up water when doing partial boils and that’s a heck of a lot more water. None of the directions for rehydrating yeast say to boil the water. Is this just people being overly cautious?

Maybe I’m overly cautious or doing it wrong :o but I boil some water in a small saucepan and cover it with a lid to cool before I start the brew day. When it’s time to re-hydrate, the water is cool enough. I also agitate the water by swirling the pot to get a little oxygen in it.

I mostly brew partial mash in a five gallon kettle. For my top up water, I buy a 2.5 gallon container (with a built-in spigot) of purified drinking water or distilled. If I remember, I put it in the fridge ahead of time to help get to pitching temp quicker. I usually use 1.5-2 gallons of it to top up.

I do boil rehydration water. I’m not sure if it is “overly cautious” or just the right amount. I also didn’t boil top off water when I did extract, and I don’t have an answer as to why.

Thanks all for the coments…I think I,ll ere on the side of caution…Tankie :cheers:

I just rehydrated US-05 and could have sworn it says to boil or maybe use sterile water that you let coll to 80deg.

I rarely rehydrate my dry yeast and I have not had a problem with my fermentations or off flavors. However, when i do, i boil my water.

http://www.fermentis.com/wp-content/upl ... A_US05.pdf

“rehydration instructions
Sprinkle the yeast in minimum 10 times its weight of sterile water or wort at 27°C ± 3°C (80°F ± 6°F). Leave to rest 15 to 30 minutes.
Gently stir for 30 minutes, and pitch the resultant cream into the fermentation vessel.
Alternatively, pitch the yeast directly in the fermentation vessel providing the temperature of the wort is above 20°C (68°F). Progressively sprinkle
the dry yeast into the wort ensuring the yeast covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes, then mix the
wort using aeration or by wort addition.”

I just rehydrated US-05 and could have sworn it says to boil or maybe use sterile water that you let coll to 80deg.[/quote]

Interesting. I must have completely missed that.

To boil or not to boil depends upon your faith in your water source. To boil or not boil top off water depends upon your faith in your water source. I would add yeast nutrient to the water if I were to ever boil the water for rehydrating dry yeast.

Fermentis:
"Before dry yeast can start fermenting, they need to absorb the water they lost during the drying process.
Yeasts are living organisms and rehydration temperature is critical for good yeast performance.
Fermentis recommends that top fermenting (ale) yeasts are rehydrated at a temperature between 25-29°C (77-84°F) and that bottom fermenting yeasts (lager) are rehydrated at a temperature range of 21-25°C (69-77°F).
Rehydration is done in a vessel outside the fermentor. The objective is to reduce the lag phase : the time necessary for the yeasts to start fermenting sugars to alcohol after inoculating the wort.
Rehydration is a simple procedure.

Rehydrate the yeast in 10 times its weight of water or wort. Gently stir. Allow a 30 minutes rest. Pitch the resultant cream in the fermenter."
Old_Dawg also posted this.

I am a newbie (been lurking the forums for a while now, though), so don’t take my word as gospel! I am also doing extract kits for now until I get a bit more experience! :smiley:

I am on my second batch right now. Followed instructions exactly for the first batch of Caribou Slobber I made, so I just pitched the dry yeast. I had vigorous fermentation for about 48 hours afterwards. The temp was also a little on the high side (of course hindsight is 20/20). I was at about 70 degrees initially. I cooled it to 68 with a wet towel and fan though. It slowed down to a stop after about a week.

My second beer is the smashing pumpkin ale. It also said to just pitch the dry yeast (which I am sure would have been OK too), but I decided to rehydrate it. I also tried to cool my wort lower than the instructions recommended. It seemed to start fermentation slower than my first brew, but it is still going strong after 5 days.

For rehydrating, I used a mason jar. I boiled about 2 cups of water (only actually used about 1 cup). I poured the water into a sanitized mason jar and let it cool to about 75 degrees in a small ice bath (covered with some saran wrap to protect the water). I then put the yeast in and let it sit for 15 minutes without swirling. You could see some activity already. I then swirled it and let it sit for another 15 minutes. By this time, my wort was nice and cool and I swirled the yeast to get it all in suspension and tossed it right in to my aerated wort. Popped the airlock on and it was good to go. Like I said, I didn’t notice anything until the next day. With my first batch, it started within hours. This time, it took longer but it definitely is still going. I’m learning as I go :slight_smile:

I just rehydrated US-05 and could have sworn it says to boil or maybe use sterile water that you let coll to 80deg.[/quote]

Interesting. I must have completely missed that.[/quote]

For me I’m glad I did boil it. Once I poured the hot water out and the pot cooled/dried it had a powder like residue on the bottom. Probably from hard water or maybe some other deposit.

I boil. My thinking is that the 5 to 10 mins it takes to boil the water is very cheap insurance against spoiling a beer that i spent so much time and money making.

Exactly right. I use warm 80-100F water directly from the tap when rehydrating. I’ve never had a problem, but not everyone will have such good water.
When I lived in the states, I would always boil the water first. Not because I feared contamination, but to drive off the chlorine. I can’t imagine it is good for yeast health.

[quote=“wmwadeii”]
For me I’m glad I did boil it. Once I poured the hot water out and the pot cooled/dried it had a powder like residue on the bottom. Probably from hard water or maybe some other deposit.[/quote]

It’s my understanding that temporary hardness elements that are driven off by boiling (Ca and Mg) is actually good for yeast health.