Double batch ?

[beauvafr]

I heard about pitching full yeast with half wort, let it ferment for 24 hours, then pitch the rest of the wort. Less yeast is needed, much like doing a yeast starter, without a yeast starter..

• First, what is it call ? Double batch ?
• Second, is it wort it?
• Third, any risk of infection keeping the extra waiting wort 24 hour in a sealed bucket for 24 hours ?

 

[NTXBrauer]

I would not risk the possibility of infection by re-introducing wort to a FV, a day after fermentation has started. IMO, it is much better practice to make a yeast starter for every batch.

 

[beauvafr]

I tought it was a common practice. As for the starter, I don't have time for it since I am brewing today.

 

[boydster]

I think it's called Drauflassen. Here's a blog post from another HBT member that experimented with doing something like what you are describing: http://woodlandbrew.blogspot.com/2012/12/no-more-wasteful-yeast-starters.html

Edit: From Braukaiser, you are fine calling it "Double Batch" (emphasis mine) -

Drauflassen (German for letting something flow onto) is a common practice in large and small breweries. Especially when the fermenter capacity greatly exceeds the brew house capacity or when fresh yeast is introduced into the brewery. It allows pitching at a proper pitching rate with a reduced amount of yeast. Cooled and aerated wort is added to fill only 1/3 – ½ of the fermenter capacity. Then the yeast is pitched. After 24 hrs, when first signs of fermentation are visible and the first batch is at low Kraeusen the 2nd batch, which has been fully aerated, is added. Hence this technique is known as Double Batch in American brewing

http://braukaiser.com/wiki/index.php?title=Drauflassen

 

[Bottoms_Up]

Interesting, but what would happen to the 2/3 of the wort that is left standing for a full day? Wouldn't wild yeast and/or bacteria find that a great medium in which to start a colony? Is there some way to protect the rest of the wort from wild yeast, etc.?

 

[CastleHollow]

You could boil the remaining wort before storing it in a sanitized bucket.

 

[Bottoms_Up]

You could boil the remaining wort before storing it in a sanitized bucket.

The wort would already have been boiled, but boiling does not guarantee that all bacteria/wild yeast has been inactivated. Leaving it for a full day seems risky.

 

[CastleHollow]

The wort would already have been boiled, but boiling does not guarantee that all bacteria/wild yeast has been inactivated. Leaving it for a full day seems risky.

It's not risky at all, boiling it kills any wild yeast. Keeping it in a sanitized container protects against any airborne contamination. It's done all the time with no chill brewing, or wort shares.

 

[Bottoms_Up]

It's not risky at all, boiling it kills any wild yeast.

You missed my point. Boiling it does NOT kill all wild yeast/bacteria. There is another thread which discusses this.

See:
https://www.homebrewtalk.com/f163/cold-hard-truth-about-rinsing-yeast-boiled-water-451925/

 

[boydster]

If you read the links I posted, you'll see it carries very little risk and is done commonly by some breweries. I wouldn't worry, as long as your sanitation is good.

 

[CastleHollow]

You missed my point. Boiling it does NOT kill all wild yeast/bacteria. There is another thread which discusses this.

See:
https://www.homebrewtalk.com/f163/cold-hard-truth-about-rinsing-yeast-boiled-water-451925/

Much of that thread talks about the differences between boiled water and boiled wort. What's pertinent to this topic is that boiled wort, while not sterile, has an acidic pH which is detrimental to bacteria. Concerns with lacto/pedio/aceto organisms are taken care of by proper sanitation. And if you keep the wort in a sanitized container prior to pitching, you minimize the risk of airborne contaminants of wild yeast during the interval before saccharomyces can take over.

So while preserved wort isn't completely sterile, the risk of contamination is small as long as you follow proper technique.

If storing wort to add to fermentation later was too great a risk, I'm sure the Germans would not have created a term for the procedure. The link boydster posted covers some of the issues you raise related to contamination. It also appears to be a worthwhile procedure to get to proper pitching quantities for lagers.

 

[Bottoms_Up]

If storing wort to add to fermentation later was too great a risk, I'm sure the Germans would not have created a term for the procedure. The link boydster posted covers some of the issues you raise related to contamination. It also appears to be a worthwhile procedure to get to proper pitching quantities for lagers.

Yes, I think it would be a great procedure to use with lagers, since it already usually takes a day or so before active fermentation takes place. And, because the wort is generally at 50 F or less, there would likely be less chance of wild yeast/bacteria activating. Ever since the last couple of years, I have focused almost entirely on lagers, and I might use this procedure for my next batch.

 

[wbarber69]

Before I finished my chiller I would swamp chill my wort. And living in Louisiana it would usually take anywhere from 8-10 hours to get down to pitching temp. And many times I would wait until the next day so I didn't have to up all night. One time it forgot to do my starter ahead of time and ended up doing it after the boil and gave it a good 12 hours on the stir plate before I used it. I've been at it for 2 years and I haven't had any infections yet. As long as your wort isn't disturbed it won't be a problem. Like everyone else here I recommend doing a starter everytime. Whether using liquid or dy yeast or even smack packs. With starters my IPAs are usually finished fermenting after 4 days leaving me with the ability to schedule my dry hopping sessions at my discretion. Lagers are done fermenting around day 6 and immediately go into secondary for lagering/storage. Extra time does nothing but make beer better.

 

[boydster]

I'd stop short of doing a starter with dry yeast, but if it works for you keep on keepin' on. Vials and smack packs, I always make a starter - there just aren't enough cells in those packages - but the dry yeast is cheaper and has about twice as many cells as long as you rehydrate properly. Topic for a different thread, though.