Bernzomatic O2: How long do you dose?

I recently switched from aerating my batches with an air filter to using pure O2 via Bernzomatic bottles from Home Depot. I got the regulator from Austin Homebrew Supply. The general consensus from the research I have done suggests that 60 seconds at 1 liter per minute is an ideal starting point but without any sort of gauge I have no way to know exactly how much O2 I am feeding from the Bernzomatic when fully opened up. I was curious how long folks using this method are hitting a 5-gallon batch. Thanks in advance.

Clark

According to Chris White and Jamil Zainasheff's book Yeast, you want 8-10 ppm dissolved oxygen to start your fermentation for mid range worts. They published a chart which showed that 60 seconds of 1 L/min of pure 02 with a 0.5 micron stone gives you 9.2 ppm. 1L per minute is not a terribly fast flow rate. I use a 2 micron stone on a benzomatic valve as well, and I suspect the flow rate is well beyond 1L/min.

So, at the end of the day, I use the very scientific method of counting to 30 with it wide open for mid range beers( 1.050ish), and count to 45 or 60 for beers with gravities going up. It is a total crapshot, but seems to have worked fine for me so far.

+1 I do about 30 seconds with a good bubble rate. I think somewhere I read that the exact L/min isn't a big deal. Repeatability, as long as you are getting good results with the amount you are doing, stick with it. If not, try more or less until you're happy and then stick with it.

... and make sure the stone is at the bottom of the fermenter, not float on or around the top. I weigh mine down and thinking about building a stainless or copper tube to put the stone at the bottom.

I attached my tube/stone to the end of a coat hanger and that's what I use to keep it at the bottom.

I just got my o2 setup about 4 brews ago, and I usually give it 3 minutes of a gentle but rolling bubble. Like halfway between "trickle" and "blast".

People say they get away with less, but I've gotten 4 batches out of the one tank and it hasn't run out yet so *shrug*.

I hit mine with 60-seconds of oxygen using the aeration wand from William's Brewing.

Seven said:

I hit mine with 60-seconds of oxygen using the aeration wand from William's Brewing.

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That's what I do as well, except I made my own wand out of a broken piece of racking cane.

Thanks for the input.

PS - Love the Blog, John.

@Revvy: On the racking cane one how many/fine are the holes you put in? I realized I didn't have a stone handy and went to chopping on some extra tubing for my last batch and was thinking about it (albeit a less rushed and more thought out approach) as an alternative to buying a stone.

I would figure he had a stone on the end... the holes on an airstone are measured in microns and I don't think holes that you could make yourself would be very efficient

badmajon said:

I would figure he had a stone on the end... the holes on an airstone are measured in microns and I don't think holes that you could make yourself would be very efficient

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Yes. I use a small piece of the vinyl tubing as a bridge connector between the cane and the SS stone.

They do work, I'm just curious as to efficiency with pure oxygen. The smaller micron stones result in larger surface area. My previous stone was ceramic but way less than 5u. If it was 15u I'd be surprised. I used to give it 30m with a sani filter but I came across a 20lb oxy tank and I've been doing to try it out but I broke my stone and haven't had the means to buy another lately. I guess I could get a pvc one if holed tube isn't worth it.