The Double Drop - Old Traditional Method

[Bribie]

This used to be a very common method of brewing in the UK, Fullers did it until they got their new vessels a couple of decades ago, and some still do it such as Brakspear (at Wychwood). The idea is to start the fermentation in an upper vessel then, after 16 hours drop the fermenting wort into a lower vessel, leaving behind unwanted proteins, hop materials etc and also giving the wort a good second aeration to promote a healthy fermentation. I read about this also in the new Jamil and White "yeast" book, so decided to give it a whirl. I couldn't really see that 16 hours was going to make all that much difference, but I'll try anything once, honey.

I note that DD hasn't been mentioned on the forum for a while now, but some guys had problems with stuck fermentations. I guess that was due to yeast being left behind and not making it into the collecting vessel - in my exercise here I used a true top cropper (Wyeast West Yorkshire Ale 1469 - traditional Stone Square stuff) and skimmed yeast from the first part of the fermentation to add into the collection vessel. I'd probably be reluctant to use this method with, say, US-05. - The Yeast book says they collected the yeast off the first tank using a "Griffin Slide" which I take it is a huge version of my big spoon so hopefully I'm on the right track.

I have brewed a red ale:

4500 Perle
300 Caraaroma
200 Carared

64 degrees 60 mins

18 Northern Brewer 60 mins
90 Fuggles flowers NZ 10 mins


No chill, pitched next day - Wyeast 1469 from previous yeast cake. I used my 25L fermenter to kick things off, around 24L in the FV. (note I slightly increased the brew length from my normal 23L to take account of the fact that some volume would be left in the 'top' vessel after the drop)

After 16 hours in the primary at around 17° we are getting yeast - actually a fairly firm layer floating, as 1469 tends to do:



Place the 25L FV on the counter, spoon off the top crop of yeast into a sanitized 30L FV and position it on floor below, starsan everything including tap.



Start the drop: I had to do it in two stages due to foaming, and during the rest I covered both FVs with starsanned lids. Stopped dropping when some turbid stuff started coming through.
If you look carefully at the bottom of the FV you will see a definite 'hard' layer of crap on the bottom, maybe the fermentation "curdles" it or something? It looks like all the cold break could be down there.





End result, a normal quantity of wort in the FV plus a jug of absolutely disgusting looking crud out of the first FV that looked like something you would pump out of a restaurant grease trap.






So now I've got a fermenter of cleansed wort with some pure fresh yeast in it, nicely aerated (twice) and bedded down at 19 degrees for the anaerobic phase. Can't wait for this one. I reckon the jug contains break and crap from the original bit of yeast cake as well. I'll top crop out of primary in a day or so for the next brew. Top cropped yeast is pure, as opposed to using sludge which as you can see contains a lot of unwanted stuff.

The main thing is that all that slimy stuff has been removed from the brew - amazing how it compacted down into a distinct almost firm layer at the bottom. I'm impressed that a mere 16 hours can produce such results. I can well see why the UK breweries used this method. If this produces a better, cleaner, faster fermenting ale I'll do it all the time from now on with top cropping yeasts. :thumbs:

[Bryggmester]

Good luck with your experiment. I used to double drop for years after reading about the method in Graham W's book, but after reading of other folks' experiences on this forum I tried just using the one FV and leaving the brew in there for 10 days or so and that seems to work fine. I don't think double dropping made a better beer and was more hassle, but you never know until you try.

[dazer23866]

this will be very interesting, just been on a tour of wychwood the weekend and they said they tried to do the beer without the double drop and it just did not taste the same.
So thats why they still do it there in the original FV from Henley

[Wolfy]

Sounds interesting, my Yeast book is still in the mail.

I guess after 16h you already have much of your yeast growth, however I'd be tempted to cover the top of your lower FV with cling-wrap and then run some sanitised plastic tube from the tap and under the cling wrap - just to minimise any airborne contaminants.

[Buzz]

*bump*

Just wondered how this beer turned out and your thoughts on this method now (if) the beer is ready for drinking?

[gnorwebthgimi]

I'm also quite keen to hear the results of this experiment.

[EoinMag]

This could definitely be interesting for BIAB brewers, keep us informed Bribie.

[L2wis]

Yeh I'm also interested, I don't BIAB but I do no chill and chuck everything into the FV and did wonder about cold break... Come on Bribie we want results

[Bribie]

Sorry I've been in the hermit cave: brew is finally ready to drink. The fermentation went quite quickly - in the past I have gone for about 8 to 10 days with most yeasts and always get a bit paranoid when I read on UK brewers websites "primary fermentation is for three days then we rack to conditioning tanks for a further few days, cask and send out to the trade" etc. However on this occasion it was all over in about 6 days and I kegged / bottled straight out of primary.

It's ended up as a really typical UK ESB with a lot of late Fuggles notes and well attenuated - nice colour and very clean flavour - and chill hazed to buggery below 12°

However I think that's to do with what happened after primary - I normally rack into a cube with gelatine, flush the headspace with CO2 and cold condition in my lager fridge which can hold 3 cubes - for around 10 days, then add Polyclar three days before kegging / bottling and all my beers are almost crystal clear going into the keg. So much so that after two or three days carbing at serving pressure they usually pour bright as a pub beer.

Anyway I have a brew day coming up on Saturday with a few guys attending and I was saving the cornie for that, so last Friday I took the top off the keg and dosed it with Polyclar and held it at -1° for a few days in my lagering fridge, and tried one yesterday - then about five more and it's not looking too bad now.



Advantages of the double drop so far, seem to be:

• Shorter more active primary
  Better attenuation which is probably due to the better oxygenation (there's a graph in the new Yeast book which predicts this)
  Less yeast trub in primary with an extra bottle for me at the end.

I'm onto my second dropped brew now, and have a new temperature controlled fridge which enables me to crash down to -1° so looking forward to the results - kegging next Monday. This is a blonde ale so nothing to hide behind there.

[Bobba]

Do you think the fast fermentation was due to the double drop, or the use of that yeast. I used 1469 on my last batch and I kegged it after 1 week instead of the usual 2-3 as it had completely done it's job in 3-4 days

[Bribie]

I use 1469 on nearly all my ales nowadays, unless for American Pale Ales etc where I use US-05 or the similar Wyeast 1056. I think that this batch did go through a couple of days quicker than I've been used to, quite possibly because of the better aeration.