[narcout]

wow, I'd never heard the bit in that link about not rehydrating yeast in water, either.  I'd always just follow the instructions on the package and added it to a bit of warm water 15 minutes before the end of the boil.  I know at the U-brew I started out at, they just add dry yeast straight to the wort...

interestingly enough, that NB article also mentions vorlauf causing HSA.  well damn, if they're worried about a bit of corlauf causing that, they must REALLY hate my straining method.

I also disagree with the premise that you shouldn't rehydrate yeast in water, especially after Sean's experiment: http://seanterrill.com/2011/04/01/dry-yeast-viability/

I don't believe vorlaufing causes HSA (unless you're doing something really funky).

[weithman5]

i don't get enough material past my toilet hose to worry about and when i biab i don't seem to have so much through the netting either.

[blatz]

Of course it's critical or the efficient Germans wouldn't have invented both the process and that neat sounding word.

I beg to differ. The Germans invented a LOT of dumb words.....

"Eisenbahn-knotenpunt-hin-und-her-shieber" which loosely translates into: "railway- crossroads-backwards-and-forwards-mover".

yes, especially when everyone knows it could have just been "der train".

[tubercle]

I usually Vorlauf about a qt when I remember to, which is about half the time. I'm usually checking for flow more than anything else. After a qt everthing seems clear.

 BTW, I use a hybrid strainer. A 1" piece of braid connected to a 4" piece of 1/2 slotted copper pipe with another piece of braid crimped on the end. The occasional chunk but very little sediment. Can't be any worse than the suicidal wasp or the walnut leaves that blow in.

[tschmidlin]

There's a Northern Brewer blogpost that actually advocates against vorlaufing.  I don't really agree, but here it is: http://www.northernbrewer.com/connect/2010/03/2-things-literature-says-i-should-do-that-i-dont/

I wouldn't just dump the yeast in the wort if it was over ~1.050.  For that I use go-ferm and water to rehydrate dry yeast.

[euge]

I'm a hydrator of dry yeast too. It's important to note that the yeast should be hydrated in plain tap water not RO, distilled or otherwise. I get krausen in 8 hours so I'm wondering if the "stripping" of FAN has that much impact vs cell wall destruction.

Does hot side aeration actually matter pre-boil?

And to answer the vorlauf question. Usually a quart or less to set the grain-bed and vorlauf. I float a plastic lid and gently pour the vorlauf onto it and the bed isn't disturbed. From now on I'll skip this.

[weithman5]

i have also made starters from partial packets of dry yeast.  i know this is frowned upon, but in my world it is not much different than   repitching a yeast slurry from a previous batch.

[Kit B]

The vorlauf will help you eliminate chunks of grain & husk that could otherwise add tannins, get scorched, or promote additional matter that you don't want/need.
I use a 10-gallon Rubbermaid cooler with stainless braid.
I typically run 2 to 3 quarts, because I run into a gallon pitcher & there's room to do so.
I place a receiving kettle under the tun, place my gallon pitcher into the kettle & put the hose into the pitcher.
When the runnings look quite clear, I drop the hose into the kettle & very slowly pour the initial runnings into the rear of the tun.
No fuss.

Addition:
HSA isn't going to occur from the mild treatment involved in most vorlaufing.
But, you could possibly be pushing your luck with that straining method.

That said...I believe HSA exists, but have never noticed it in my brews, or anyone else's.
...Kinda like the way I believe in sasquatch.

[tygo]

Does hot side aeration actually matter pre-boil?

Theoretically it does create oxidized compounds that are not volatilized during the boil.  In practice normal handling of the wort doesn't seem to have much of an effect.  At least not at the homebrew level.

[kgs]

I mash in a 5-gallon Rubbermaid cooler (trimmed with blue painter's tape to increase efficiency) using a foot-long (I think) "Denny braid." I always end up vorlaufing because I don't know if I need to vorlauf until I've poured off a couple of cups of wort, at which point, I *is* vorlaufing. It's usually between 3 and 4 cups because I use a 4-cup Pyrex. In my opinion, based on what I see, the vorlauf is usually unnecessary, but it's not like it takes much effort, and then I get to throw around words like "vorlauf."

I have become a dry yeast sprinkler, simply to avoid one more contamination opportunity. My beers rarely exceed 1.070. My ales always kick off with great enthusiasm. My stouts never do, and also finish too high. Hmmm. But now we have a hybrid thread...

[morticaixavier]

Does hot side aeration actually matter pre-boil?

Theoretically it does create oxidized compounds that are not volatilized during the boil.  In practice normal handling of the wort doesn't seem to have much of an effect.  At least not at the homebrew level.

I brew alot of partigyle brews and I have only one kettle that is big enough to hold a preboil volume of wort, even for the small beer. So I run my first runnings off into the boil kettle, get that on the burner and then run off the second runnings into a bucket. When the first boil is over I pour the second runnings into the kettle. I take 0 precautions against HSA and have never noticed any problems. I have not entered any contests so perhaps I am just missing it but...

[tygo]

I take 0 precautions against HSA and have never noticed any problems. I have not entered any contests so perhaps I am just missing it but...

I agree with you.  I've read / heard interviews where people who know what they are talking about (Bamforth, Fix, etc) say it exists, but I've never had a problem with it and I'm not especially careful about it.

[euge]

Does hot side aeration actually matter pre-boil?

Theoretically it does create oxidized compounds that are not volatilized during the boil.  In practice normal handling of the wort doesn't seem to have much of an effect.  At least not at the homebrew level.

I brew alot of partigyle brews and I have only one kettle that is big enough to hold a preboil volume of wort, even for the small beer. So I run my first runnings off into the boil kettle, get that on the burner and then run off the second runnings into a bucket. When the first boil is over I pour the second runnings into the kettle. I take 0 precautions against HSA and have never noticed any problems. I have not entered any contests so perhaps I am just missing it but...

I as well, though have nothing to back it up with. However, if it can happen I will make it so- however unwittingly it is done.

One of those notions that have been bothering me as I vorlauf and lauter.

[djt17]

On the last episode of "Drinking Made Easy", they were at the Allagash brewery in Maine. As soon as the boil was over they were pumping hot wort from the boil kettle to a large open fermenter. It dropped about 6 ft to the fermenter; splashing & foaming all over the place. I thought if HSA was real, this should be it.

[morticaixavier]

On the last episode of "Drinking Made Easy", they were at the Allagash brewery in Maine. As soon as the boil was over they were pumping hot wort from the boil kettle to a large open fermenter. It dropped about 6 ft to the fermenter; splashing & foaming all over the place. I thought if HSA was real, this should be it.

unless they purge the fermenter. I imagine there is a time aspect to it as well.

as I understand oxidation first you introduce o2 then, over some period of time, that o2 interacts with other compounds in the wort/beer causing unpleasant or unwanted flavours/aromas. the higher the temp (within a limit) the faster these reactions occur. The higher the level of disolved o2 the faster and more extreme these reactions occur. and the longer the disolved o2 stays in the wort/beer and the wort/beer stays at an elevated temperature the more these reactions occur.

so when I pour my hot wort from a bucket to the kettle I am introducing o2 and oxidation reactions commence. I then add heat which drives off disolved o2 until it reaches a boil when pretty much all the o2 is removed from the solution thus halting the reaction quickly.

with allagash they pump the hot wort into the fermenter where o2 is introduced and reactions commence. they immediatly begin cooling the wort via what ever chilling method they use thus slowing the reactions and then add yeast which remove much of the remaining o2 in fairly short order.

Perhaps if you agitated your hot wort and then let it sit overnight you would notice some effects. I am unlikely to try this experimen.