homebrewandbeer.com

I found the olive oil document at:

http://anthonyrants.com/OliveOil.doc

I'm assuming it is undoctored from the original...

Apologies for extreme topic offness...

This needs it own topic.

Cheers,
Greg

Had originally started here.

Cheers,
Greg

Also from Brewcrazy, the same in pdf format (bit smaller and more people have the FREE Adobe Reader).

http://www.brewcrazy.com/hull-olive-oil-thesis.pdf

Read the article on it in the latest BYO magazine. For the average 20L HB batch you need ~6mg of olive oil. It was suggested you dip a piece of wire in oil and then stir the starter with it!

Might have found a use for my 10uL syringe

Interesting. Can anyone think of a suitable solvent to use for a dilution?

Perhaps lecithin and water...

Which makes me think, perhaps you could use lecithin instead of olive oil...

So something like an eye dropper might be the go? Just a single drop would be plenty I guess?

Been wanting to have a go at this for a while now, but could never really find any good info for using it in HB (23L) size batches.

One drop is way too much.

I like the wire idea (unless you can get your hands on a micropipetter). eye droppers are too innaccurate, the smallest drop you'd be able to get out of that would be about 1/4 of a ml with is atill 250ul... which is about 40x what you need. This is assuming that 1ml of olive oil = 1g. (its prolly more).

Is it possible to overdose on it though?

My interpretation was that too much was just too much, it had no adverse effect?

well you dont want to just pour the oil into the starter... i think in order to obtain similar results, you have to try to emulate the experiment as accurately as you can.

I'm willing to give it a go, especially because i dont have a magnetic stirrer/agitator to aerate the starter before pitching, so adding the oil 5hr before pithcing will help in the production of the sterols and other compounds necessary for cell production.

And here I was thinking I'd experiment with my latest brew, mashed it with ½ litre of olive oil. Slowed the sparge up, but hey, it was a trial.
Almost no head on the beer, but it's great with salad.
Maybe next time I'll try about 50 mil of balsamic vinegar in the mash too.

Seriously, I have read about this before, it was also discussed at some length on the NB forum and, if memory serves me correctly, the Craftbrewer podcasts mentioned it in one episode. I guess if it works (and I have no evidence one way or the other) then I can see how not having to aerate your wort would help to reduce potential oxidation problems.

My plan is to build a starter on my stir-plate as per usual, which means cooling it in the fridge and disposing of the beer before pitching the yeast into my wort. I will add the oil immediately before chilling.

To get the amount right, I think I will boil a drop of oil in a saucepan of water and spoon some into the yeast. Or, dropping the oil into the starter at the beginning and watching the excess go down the drain with the starter beer...

I have an even better question, why do we need the cells to reproduce in the wort? Is the oil even necessary?

As far as I can tell the only reason to aerate is to shorten the lag time and ferment quicker, but it is detrimental to the beer! So why can we not just go through the entire process, making sure not to introduce any oxygen to the wort, then pitch a large enough slurry of healthy yeast to fully ferment the wort without any reproduction? Sure if you were selling the beer, and you needed a quick turn around this would be a concern, but for us craft brewers who harp on about quality, should we not be taking every measure to keep oxygen out of our wort?

PS: Before SMOI gives his obligatory speech about oxygen being necessary for ester production (though I do believe it impacts higher alcohol production) I will again point out that I do not agree with this theory.

Er, I thought that not oxygenating simply stressed the yeast, preventing proper cell wall formation. And as we all know, stressed yeast = crap fermentation. I'm sure that if you pitch a large enough population of happily fermenting yeast that you'll mitigate the problem, but how do you propose to get said population without aeration?

Have a read of the document in conjunction with Jamil's writings on yeast starters. The introduction discusses the need for this quite succinctly and Jamil speaks with a good balance of theory and practice.

As I read it, it is generally accepted that you need around four yeast replications in order to get what the experts reckon is the right amount of esters in the finished product. You also need the yeast to be healthy. If you do not generate the right number of healthy yeast, you can get spastic yeast which do not do all that is required to make the best beer...

rwh, I am assuming the yeast that is pitched is already in a healthy active state, and that there are enough cells to fully ferment the wort without becoming stressed.

SMOI, I think you will find that Jamil refers to slurry which has used up it's reserves and is not in a healthy state to begin with. He also does not say that the yeast will not produce esters without oxygen or growth, he assumes you need oxygen for growth to have the proper amount of yeast to produce the right ester profile for the beer. But the growth itself actually impact adversely on the ester profile.

Kevnlis wrote: PS: Before SMOI gives his obligatory speech about oxygen being necessary for ester production (though I do believe it impacts higher alcohol production) I will again point out that I do not agree with this theory.

When the technical guys from all the major yeast suppliers, including Wyeast and White Labs say something, well-respected and awarded homebrewers say the same thing, several respected brewing experts write that same thing in published books/papers and what they are all saying is reflected in the practices of every professional brewery I have seen or read about, you will need to do more than this to convince me.

Kevnlis wrote: SMOI, I think you will find that Jamil refers to slurry which has used up it's reserves and is not in a healthy state to begin with. He also does not say that the yeast will not produce esters without oxygen or growth, he assumes you need oxygen for growth to have the proper amount of yeast to produce the right ester profile for the beer. But the growth itself actually impact adversely on the ester profile.

Read Jamil's writings. He does not constrain what he is saying to slurry - if he did he would not advocate treating brand new liquid yeasts the way he does...

Why would I try to convince you of anything? I could really care less what you think...

I was pointing out that I know your opinion, I do not agree, and I did not wish to argue the point...

I have read Jamil's writings on the subject, and I am sure he is very well educated and has impeccable sources.

This doesn`t revolve around the comment last week re. the tailor made suit and the suit off the rack,now, does it?