double Drop System

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Slack Brewery
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Double Drop fermentation makes Brakspear beer unique

Double Dropping, also known as the Dropping System of fermentation, was for the first half of the 20 th Century the most popular method for the fermentation of traditional English Ales.

It involves starting fermentation of the wort (fermentable liquid rich in malted barleys sugars) in one vessel, followed by dropping this liquid under gravity into a second vessel below it, usually on the second day of fermentation. Here it continues its fermentation for two or three days. The beer is then slowly cooled over the next couple of days, during which time it matures and gains complexity.

source: Brakspear Brewery

Tried a variation of this with a Dunkelweizen that was brewed yesterday. "dropped" into another fermenter first thing this morning, just had to replace with the airlock with a blow off tube, fermenting at 20C. Found this from the Hobgoblin poster website. Yeasties seemed to like the extra attention. I imagine that this method is running all sorts of risks though :)

Explaination of how I used this method.
Set the fermenter on a bench and opened the tap so the brew dropped into another fermenter. Cleaned out the now empty primary (as I left most of the cold break in the first primary fermenter), sanitized then poured the brew back into the cleaned fermenter (a little short on fermenters hence the return to the original fermenter). If the method works, it seems a good way to deal with cold break when using counter flow wort chiller. Otherwise it could be a good method of getting infections into your brew <_<
If you did this after one day - you might be allright aerating the wort again from one fermemnter to the other and back....

However, at three days it is not good to airete...will need to use a racking tube so that the wort from the primary went to the bottom of the secondary so as to reduce oxygenation...
Dropping with aeration on day one after pitching is a VERY good technique, esp with strong beers. The yeast use this oxygen to repair cell walls cratered where new cells were budded off. With this second aeration the yeast can generate sterols and fatty acids to repair those crater marks greatly improving the health of the cell.

Where a ferment is sluggish I re-aerate twice a day up to and including the third day, after that transfers are by racking, i.e. no aeration.

Jovial Monk
No aeration on racking, JM? Are you sure?

I didn't think it was possible to rack without introducing oxygen to the beer, or do you push it out under CO2 into a flushed fermenter?

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