Oxygenate

[Dro]

Hi, I am onto my second brew kit, the first is in bottles in the garage after following lots of great advice on this forum, so I decided to buy a Youngs APA next which I really fancied. In the instructions it says before adding the yeast to stir vigorously to oxygenate to get the yeast off to a good start. Would it be OK to use a degassing tool with the cordless drill or is that unnecessary? Thanks. Andy.

 

[Cwrw666]

Waste of time. Just float your dried yeast on the surface. That's where all the oxygen is anyway.

 

[dan125]

Would it be OK to use a degassing tool with the cordless drill

That's how I do it

 

[Dro]

Waste of time. Just float your dried yeast on the surface. That's where all the oxygen is anyway.

Thanks

 

[Dro]

That's how I do it

Cheers!

 

[Deathstar]

Yup, I used my whirlpool wand to oxygenate the wort. If you boil you drive off all the oxygen in solution. You need to get that oxygen back into the solution, so the yeast can have a good start.
Some commercial brewers actually infuse oxygen in the wort as it transfers to the fermenter through inline oxygen injection.

 

[Arrakus]

Waste of time. Just float your dried yeast on the surface. That's where all the oxygen is anyway.

I’ve neglected to oxygenate a couple of times, never noticed a difference in the finished beer to when I did the same recipe and oxygenated

 

[marshbrewer]

If you boil you drive off all the oxygen in solution.

Bit the OP is kit brewing, so it's unlikely that they will have done that? You have to stir a kit fairly vigorously to mix the malt extract and tap water, and in my experience that was sufficient. In other words, if you have managed to mix the water / kit into a unified liquid, you are good to go and can sprinkle the yeast.

 

[terrym]

If you boiled some or all of your water (e.g as in AG) or are using bottled water you need to re-oxygenate the water to help the yeast. However if you are making up a kit with tap water the water already contains oxygen. '
But in either case there isn't much need to spend ages trying getting air into wort since oxygen doesn't dissolve in water very easily (unlike CO2 which forms a weak chemical bond) so wort will become oxygen saturated very quickly. So other than a minute or so of a good thrash with a spoon or similar to get a foam on top of the wort any else is completely unnecessary.

 

[Deathstar]

Bit the OP is kit brewing

Missed that, cheers.

 

[Dro]

Thanks for the advice and the thought that went into it.

 

[kelper]

For kits, I stir with a slotted spoon half in and half out, so the liquid rushes through the slots.

 

[Toastkid]

I’ve neglected to oxygenate a couple of times, never noticed a difference in the finished beer to when I did the same recipe and oxygenated

FWIW with my last brew I didn't really bother, I just poured it straight into the fermentation vessel after boiling and left it overnight (sealed) to cool down. Now that I think of it, it did take quite a while to start bubbling, but once it got going it bubbled away merrily for several days. The resulting beer is absolutely lovely, and probably about 5.0% i think. So, maybe it slows it down, but it didn't seem to harm the end result.

 

[Drunkula]

If you want the best for your yeast rehydrate it in plain water at around 35c for about 15 minutes before pouring it into the beer. Jamil Zainisheff and Chris White who wrote a book on yeast say it all the time on podcasts, and Chris White has a yeast factory. They've even said that recent advice from companies to sprinkle the yeast directly is a load of ****. I found out recently that even pouring liquid yeast into a high gravity wort can still cause osmotic shock and kill a load of the cells, so the damage it does to dry yeast who haven't even set up their cell walls yet is much worse.

If you're oxygenating you might as well do right by your yeast at the same time.

Nice little read.
https://bkyeast.wordpress.com/2013/03/13/more-on-yeast-rehydration/

 

[Cwrw666]

If you boil you drive off all the oxygen in solution. You need to get that oxygen back into the solution, so the yeast can have a good start.
Some commercial brewers actually infuse oxygen in the wort as it transfers to the fermenter through inline oxygen injection.

The only `oxygenating' my brews get is when I transfer from the boiler to the FV. But as I do this while still hot I can't see that much oxygenating will occur. I then no chill for several hours before pitching. Always get a vigorous start to fermentation - that is with floating the dried yeast on the surface. Much worse if I rehydrate the yeast and pour it in. I can only assume that's because the rehydrated yeast sinks down into oxygen deprived wort while the floated dry yeast stays up at the surface where the oxygen is.
However, I can well imagine that it's totally different for commercial brewers who have vast quantities of wort to deal with.

 

[nixhaz]

If you want the best for your yeast rehydrate it in plain water at around 35c for about 15 minutes before pouring it into the beer. Jamil Zainisheff and Chris White who wrote a book on yeast say it all the time on podcasts, and Chris White has a yeast factory. They've even said that recent advice from companies to sprinkle the yeast directly is a load of ****. I found out recently that even pouring liquid yeast into a high gravity wort can still cause osmotic shock and kill a load of the cells, so the damage it does to dry yeast who haven't even set up their cell walls yet is much worse.

If you're oxygenating you might as well do right by your yeast at the same time.

Nice little read.
https://bkyeast.wordpress.com/2013/03/13/more-on-yeast-rehydration/

That's really interesting. So even if making a starter up from dry yeast, it sounds like it would be advantageous to rehydrate it in plain warm water before pitching into the starter wort?

 

[Northern_Brewer]

You need to get that oxygen back into the solution, so the yeast can have a good start.

Not if they're dried yeast. Yes yeast need oxygen to make sterols which they need for replication, but dried yeast are grown in a way that gives them enough sterols to do three generations of replication which is about all they do during a fermentation in any case. So you don't need to oxygenate wort when using dried yeast - and the beer will be better if you don't.

 

[Traptickler]

Hi Dro,
There’s a good article on the subject here The Biochemistry of Yeast - Aerobic Fermentation | MoreBeer