Dry yeast

[WizardBill]

Quick question:

I have only ever used liquid yeast. Now that I am trying to find gluten-free brews, and experimenting with different things. So, is pitching dry yeast different/harder than liquid? Any tricks to it?

 

[tx-brewer]

Just toss it in. Easy as that. You can rehydrate by using instructions on the package, but it really isn't necessary, just helps it to start a little faster, I never dehydrate though

 

[hunter_le five]

Not really, dry yeast is pretty simple. You can just throw it straight into the wort from the packet, but I like to prime it in some warm water (85-95*F) for 15 minutes before pitching to get it going.

I've heard of some people using sugar water and wait for foam before pitching, but I've never tried this.

 

[LovesIPA]

Using sugar water is bad idea, and so is pitching dry yeast directly into the wort.

You should rehydrate in water before pitching.

 

[WizardBill]

Using sugar water is bad idea, and so is pitching dry yeast directly into the wort.

You should rehydrate in water before pitching.

So, 1: Why? 2: Why?

I am just learning, so... Why?

 

[chocotaco]

My question about dry yeast is: How come Danstar says there's no need to oxygenate when you use dry yeast? They include some kind of nutrients that obviate the need for oxygenation?

If so, is there any way to add the same nutrients when using liquid yeast to avoid the need for oxygenation?

 

[hunter_le five]

Using sugar water is bad idea, and so is pitching dry yeast directly into the wort.

Can you elaborate? I often hear this, but I've never heard why.

 

[joyceman]

Ive been told that the yeast will be come accustomed (on a biochemical level I guess) to processing sucrose and become less effective at processing maltose. since the majority of your fermentables is maltose, this is a bad thing.

 

[IslandLizard]

Using sugar water is bad idea, and so is pitching dry yeast directly into the wort.

You should rehydrate in water before pitching.

Exactly! And follow the manufacturer's instructions to a T.
Just pitching dry yeast in your fermentor kills have the cells.

Before pitching, you also want to bring the thus created slurry within 10-14°F of the wort temps, either by cooling the yeast slurry down (ice bath) or by attemperating the slurry with a few smallish wort additions.

It really sounds harder than it is. You don't have to make starters, unless you have a big, big beer.

 

[LovesIPA]

Dry yeast is not just yeast. There are nutrients and other reserves that the yeast will need when they begin fermenting wort. If you pitch them into sugar water, they start using up those nutrients and reserves and they won't have them when they start fermenting wort. Additionally, if you make a starter with liquid yeast you're supposed to use DME. Not table sugar. You want the yeast to be acclimated to the environment you're going to be pitching them. If they're accustomed to fermenting sugar water, they aren't going to perform as well when they ferment wort.

Chris White (of White labs) and Jamil Zainasheff's book "Yeast" says that pitching dry yeast directly onto wort kills about half of the yeast. I'm not entirely sure why, and there are not many people whose word I take at face value in the brewing community, but these two guys know their stuff. And if they say something like that, I'm pretty confident it's true.

 

[LovesIPA]

My question about dry yeast is: How come Danstar says there's no need to oxygenate when you use dry yeast? They include some kind of nutrients that obviate the need for oxygenation?

If so, is there any way to add the same nutrients when using liquid yeast to avoid the need for oxygenation?

I don't know why they would say that. The yeast need oxygen in the wort to reproduce. I don't know why it would matter whether the yeast came from a packet, vial, or starter vessel.

 

[sweetcell]

My question about dry yeast is: How come Danstar says there's no need to oxygenate when you use dry yeast? They include some kind of nutrients that obviate the need for oxygenation?

If so, is there any way to add the same nutrients when using liquid yeast to avoid the need for oxygenation?

to over-simplify: dried yeast are "freeze-dried" at the height of health. they have all the nutrients they needs, including sterols, so no need to provide sterols when they come back to life. O2 is the easiest and most common way for for yeast to make sterols. since dry yeast already has its required sterols, O2 is not needed. if the yeast don't consume the O2, other critters might... usually yeast is quick to eat up all available O2 thus starving off the invaders. if the yeast don't need it, the critters will use it for their own nefarious purposes.

Can you elaborate? I often hear this, but I've never heard why.

using sugar to rehydrate is bad for two reasons. one, as previously mentioned, it can compromise yeast's ability to consume more complex sugars like maltose. second, when dried yeast are rehydrating themselves they suck in everything, indiscriminately. they can't control what is entering their bodies. rebuilding yourself with water = good, building your body with sugar = bad. it's water that was removed when they were mummified, so it's water that needs to be added back as they return to life.

 

[BigFloyd]

to over-simplify: dried yeast are "freeze-dried" at the height of health. they have all the nutrients they needs, including sterols, so no need to provide sterols when they come back to life. O2 is the easiest and most common way for for yeast to make sterols. since dry yeast already has its required sterols, O2 is not needed. if the yeast don't consume the O2, other critters might... usually yeast is quick to eat up all available O2 thus starving off the invaders. if the yeast don't need it, the critters will use it for their own nefarious purposes.



using sugar to rehydrate is bad for two reasons. one, as previously mentioned, it can compromise yeast's ability to consume more complex sugars like maltose. second, when dried yeast are rehydrating themselves they suck in everything, indiscriminately. they can't control what is entering their bodies. rebuilding yourself with water = good, building your body with sugar = bad. it's water that was removed when they were mummified, so it's water that needs to be added back as they return to life.

Well said.

Lots of brewers get away with not rehydrating dry yeast due to the shear number of cells contained in an 11g packet. I prefer to rehydrate.

If you want a detailed explanation as to how sprinkling dry into wort kills up to half of the cells, run a search here for "Clayton Cone". He's a microbiologist who has worked with Lallemand.