I was just reading Lallemand’s instructions for using Nottingham Ale yeast
and they state that the yeast has an adequate reservoir of carbs and
unsaturated fatty acids to achieve active growth. “It is unnecessary
to aerate wort.” I am brewing a partial mash Irish Red Ale so we will see.
Any thoughts?
Aeration introduces an ample amount of oxygen but maybe it is unnecessary but brewers have been doing it for years so it is a very small step to ensure proper yeast growth. It doesn’t hurt the beer so if it gives someone peace of mind than I say it is necessary.
I would tend to agree with them. My first brew I did was using Danstar and I totally forgot to aerate; it fermented fine and turned out fine. Of course, it probably wouldn’t hurt to aerate it a little for insurance.
Think about why you aerate. It’s because the yeast uses the O2 to synthesize sterols. These sterols keep the cell walls pliable, which makes budding, and therefore cell growth, easier. When you pitch dry yeast , you’re pitching so many more cells than with liquid that cell growth isn’t a big deal. In addition, as noted, the dry yeast is coated with nutrients to get it off to a good start. While it probably own’;t hurt to aerate, it’s really not necessary.
My personal experience is that aeration is not necessary unless you want to harvest the yeast for repitching. Even with liquid yeast, fermentation will go fine and right to completion without aeration, but the cells are not going to be in good shape at the end of that, and they will not perform well in the next batch. YMMV.
This ^^^^. The man knows what he’s talking about. My LHBS owners have expressed the same theory.
I made the same exact recipe twice in a row. The first time I aerated very well. The fermentation was aggressive and long lasting and complete. I hurt my back picking up the carboy and shaking it to aerate. The second time I did not want to hurt my back or risk the injury I would incur by having a carboy breakage while shaking it so the aeration was poor. The fermentation was not near as aggressive as the first time. It seemed to not last as long. And the result was a somewhat incomplete fermentation. The final gravity seemed too high. I have moved from glass carboy to a plastic bucket and I now aerate with a mixer that is driven by my drill and I get massive aeration. The resulting fermentations are fantastic, aggressive, and complete. My sample set is small but I will always take that step of aerating the wort. It seems like an easy step to do, and even if it’s not necessary I don’t see the harm. What would be the drawback? Is there any?
I use a stone, a regulator, and an O2 tank.
I see postings where people are concerned about no activity after 2 or 3 days. I generally see action in 8 hours are less.
I gotta think the oxygenation improves the timelines.
O2 is not required and will not help the process when using dry yeast as the OP has found though his own research and as Denny has noted above.
Below is a good quote that covers the spectrum for using dry yeast. Note that 02 can be added during ferment to help keep cell walls fluid when encountering ferments such as high gravity beer or naturally higher gravity wine ferments when more doublings/ budding will need to happen to bring the beer/ wine to terminal, but in typical beer ferments there is more than enough sterols to keep cells budding naturally until these sterols/ lipids are depleted at the end of a cycle then will need 02 when re-pitched to re-build sterol reserves. In other documents it is noted that liquid slurries contain <1.0%( 0.02-0.04%) sterol reserves when depleted and when “recharged” with 02 in starters and at the beginning of the brewing cycle will hover around 1.0-1.2% and dry yeast contains over 5.0% before pitched. Thus more than enough, although if you feel more comfortable simply adding 02 to all ferments it will not hurt much either.
Lallemand:
" The lipids in the cell wall act as a growth factor by keeping the cell wall fluid, allowing buds to form. The production of these lipids require trace amounts of oxygen to move the squalene to the lipid stage. With out O2 the mother cell cannot produce any lipids and must shares her lipids with her daughter cell. This can occur for about 3 - 4 cycles before the cell wall becomes leathery and will not allow a new bud to form. Active Dry Beer Yeast initially contain enough lipids in their cell wall for 3 - 4 growth cycles. This is enough to complete most beer fermentation’s. Recycled yeast usually do not contain enough lipids for 3 - 4 growth cycles. The lipids must be replenished with fresh additions of Oxygen.
In low gravity brewing, oxygen at the beginning of the fermentation is usually adequate. It is when you get into hi gravity brewing that additional oxygen is helpful after 12 to 24 hours of fermentation. Dr. Mike Ingledew has found that aeration at about the 14th hours is optimum for high gravity brewing. We have found that aeration after 36 hours is optimum for wine fermentation’s.
D.Briggs on dry yeast: Brewing: science and practice.
" Such cells should be sterol replete and have little or no requirement for oxygenation of worts"
" During fermentation there are usually no more than two to three cell doublings."
[quote=“JMcK”]I use a stone, a regulator, and an O2 tank.
I see postings where people are concerned about no activity after 2 or 3 days. I generally see action in 8 hours are less.
I gotta think the oxygenation improves the timelines.[/quote]
I do too, both for the reasons above, and because it was a toy I could buy from the brew catalog. YES I have a problem, first step is admitting it right???
actually it was a father’s day gift, but same concept
I too use a stone and an O2 tank. But when I started this post
I thought I would experiment and follow the yeast manufacturer’s recommendation.
Well I re hydrated it and pitched at the recommended temp then cooled down to 59F
and by gosh it was fermenting the same day I pitched it. I will still probably
aerate since I have the capability but I did think this was interesting.
Denny,
I’m contemplating a really big big for later in the year (14-15%), would adding a lot of dry yeast still make aerating unnecessary? What MrMalty says, plus 5-10 grams more.
[quote=“fullhousebrew”][quote=“JMcK”]I use a stone, a regulator, and an O2 tank.
I see postings where people are concerned about no activity after 2 or 3 days. I generally see action in 8 hours are less.
I gotta think the oxygenation improves the timelines.[/quote]
I do too, both for the reasons above, and because it was a toy I could buy from the brew catalog. YES I have a problem, first step is admitting it right???
actually it was a father’s day gift, but same concept[/quote]
Well of course it’s a toy. :cheers:
That’s true of a lot of home brew equipment too. I mean I can’t say my tastes are refined enough to notice flavor impacts of pitch rates, but I do a yeast starter for every batch because I made that stir plate and want to use it.
[quote=“Rookie L A”]Denny,
I’m contemplating a really big big for later in the year (14-15%), would adding a lot of dry yeast still make aerating unnecessary? What MrMalty says, plus 5-10 grams more.[/quote]
Yep. That’s exactly what I’d do. You may not even need the extra.
First, for your own sake, NEVER pick up a full carboy and shake it. It’s way too dangerous!
Now, with all due respect, it would have made a better experiment if you had split a batch of wort to test. I’ve done what you did many times and never seen a difference, so now we have two sides of the coin.
[quote=“Denny”][quote=“Rookie L A”]Denny,
I’m contemplating a really big big for later in the year (14-15%), would adding a lot of dry yeast still make aerating unnecessary? What MrMalty says, plus 5-10 grams more.[/quote]
Yep. That’s exactly what I’d do. You may not even need the extra.[/quote]
Thanks Denny. The extra would be more to cover the yeast not being brand spanking new. I brewed an octoberfest on wednesday and MrMalty said around 15-16 grams, but I used S-189 that was repackaged by a HBS with no indication of a best by date so I used two full packs, just to be safe.
