Return to TheElectricBrewery.com
  [ Shop ]   [ Building ]   [ Using ]   [ Recipes ]   [ Testimonials ]   [ Gallery ]   [ FAQ ]   [ About Us ]   [ Contact Us ]   [ Newsletter ]

Log inLog in   RegisterRegister   User Control PanelUser Control Panel   Private MessagesPrivate Messages   MembershipClub Memberships   SearchSearch   MemberlistMemberlist   Photo AlbumsPhoto Albums   Forum FAQForum FAQ

Using oxygen for starters

 
Post new topic   Reply to topic   Printer-friendly view    TheElectricBrewery.com Forum Index -> Yeast & Fermentation
View previous topic :: View next topic  
Author Message
mjo2125



Joined: 27 Feb 2017
Posts: 185
Location: Dayton, OH

Drinking: FuP Helles Bock

Working on: TBD


PostLink    Posted: Mon Mar 11, 2019 10:29 am    Post subject: Using oxygen for starters Reply with quote


        Register to remove this ad. It's free!
Instructions for making starters include using a stir plate for several hours to introduce oxygen into the starter wort. Are there any issues with using pure oxygen and a wand/stone to inject oxygen in lieu of the stir plate to save time?
Back to top
kal
Forum Administrator


Joined: 12 Dec 2010
Posts: 9839
Location: Ottawa, Canada

Drinking: German Lager, Electric Hop Candy Jr, Scottish 70/-, Janet's Brown, Maibock, Kolsch, Russian Imperial Stout, Black Butte Porter

Working on: West Coast Blaster (American Red IPA)


PostLink    Posted: Mon Mar 11, 2019 12:14 pm    Post subject: Reply with quote

Most instructions for making starters will tell you to use a stir plate until fermentation is completely done - that's typically a day or two, or possibly longer depending on the age of the yeast (older yeast will take longer to build up and finish). Really fresh yeast may be done within 12-24 hours, I've had packs that are 6-12+ months take 3-5 days.

The constant stirring introduced by a stir plate helps speed up fermentation and also introduces atmosphere which has the O2 that the yeast needs.

Starters are typically low gravity (around 1.030-1.040) so using pure oxygen isn't required to get to optimal O2 levels for maximum yeast growth. Seems like overkill and would be hard to regulate the slow constant addition of O2 over a day or two not to mention that at the rate you'd be introducing O2 it wouldn't be stirred, so I don't see how it would speed things up. With constant pure O2 addition it may also be possible to over oxygenate which may have other consequences.

Using pure O2 (or even an aquarium pump) would also cause the wort to foam a lot. You'd need a much larger container or flask to avoid it bubbling over (just like when you aerate 'regular' wort with pure O2 or an aquarium pump - it tends to foam up a lot).

From Mr Malty:

Quote:
Q: Should I add oxygen to my starter?

Yes. You'll get far healthier yeast and far more yeast growth if the yeast have oxygen throughout the process. Adding oxygen at the beginning helps, but the most effective starters provide a continuous source of oxygen. Oxygen is critical to yeast growth. Not providing any oxygen to the yeast can have a long-term negative impact on yeast health. Yeast use oxygen to synthesize unsaturated fatty acids and sterols, which are critical to creating a healthy cell membrane and good cell growth. With oxygen present, yeast convert sugar to carbon dioxide and water and they grow rapidly. With no oxygen, yeast create alcohol, grow far more slowly, and reach a lower total mass of cells.

There are several ways to add oxygen: intermittent shaking, a stir plate, pure oxygen, or an air pump with a sterile filter.

A stir plate is perhaps the most effective method. When using a stir plate, don't plug up the starter vessel with an airlock. A sanitary piece of aluminum foil or a breathable foam stopper is all you need. Bacteria and wild yeast can't crawl and a loose fitting cover will allow for better gas exchange.

Shaking the starter as much as possible, every hour or two, makes a large difference in the amount of yeast growth and health. With enough attention and good air exchange, shaking is just about as effective as a stir plate.

Continuous air from a pump and sterile filter can be effective too. The major drawbacks are being able to control the flow of air to prevent excessive foaming and evaporation of the starter. Shaking is just as effective as intermittent aeration with a pump.

Continuous pure oxygen from a tank or oxygen generator is both expensive and unnecessary.


My "HOW-TO: Making a yeast starter" instructions: http://www.theelectricbrewery.com/forum/viewtopic.php?t=30668

Cheers!

Kal

_________________
Our new shop with over 150 new products: shop.TheElectricBrewery.com
Purchasing through our affiliate links helps support our site at no extra cost to you. We thank you!
My basement/bar/brewery build 2.0
Back to top
View user's photo album (21 photos)
mjo2125



Joined: 27 Feb 2017
Posts: 185
Location: Dayton, OH

Drinking: FuP Helles Bock

Working on: TBD


PostLink    Posted: Mon Mar 11, 2019 3:49 pm    Post subject: Reply with quote

Kal, thanks. Sounds like my premise was wrong. We donít stir to add O2 quickly- adding O2 quickly doesnít equate to a faster yeast growth.
Back to top
Display posts from previous:   
Post new topic   Reply to topic   Printer-friendly view    TheElectricBrewery.com Forum Index -> Yeast & Fermentation All times are GMT
Page 1 of 1
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Support our site by purchasing through this link. We thank you!

Forum powered by phpBB © phpBB Group