Author Topic: Adding Dry-hops to Commercial-sized Fermenter... best method?  (Read 2500 times)

Offline wamille

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We just brewed the first commercially produced IPA in the history of South Korea this past Saturday at a small 7-bbl brewery northeast of Seoul.  We used 15 lbs of hops in the boil kettle (60/15/flameout shedule).  The South Korean brewers' heads about exploded at the amount of hops we used - they had never seen that kind of massive hop addition.  From my understanding, they use 4 lbs at most for the five regular beers they brew.  I tried telling the head brewer that we also needed to dry-hop the beer.  He was really confused and hesitated about it.  However, he has since been told that we will be dry-hopping the beer when the gravity is under 1.020 and to just do it basically.  My only concern is how to hop a beer in a 20 hecto-liter fermenter?  I have three pounds of leaf hops (2 lbs Cascade/1 lb Centennial).  I figure we'll just rip open the foil bags and toss them in the top.  But how will we drain the fermenter later?  I'm guessing that most of the leaf hops will stay on top... and a few will drop to the bottom.  I watched them attach a large hose (with a small glass piece inserted near the tip) when emptying that same fermenter... and subsequently cleaning it out.  The beer that was in the fermenter was bled of the yeast into a large plastic bucket.  When the beer was running clear, they pumped it into a bright tank.  As these guys have never dry-hopped, and I've never dry-hopped at this level, what are the concerns?  I'm guessing we just blow out the yeast and hops in the bottom of the conical fermenter and let the clear beer flow into the bright tank until it fills to the top... or 10 hecto-liters.. and then discard the rest of the beer so we don't introduce hop particles into the bright tank???  I'd appreciate any advice for our first commercially-produced IPA... and first dry-hopped beer in South Korea!!!   :o  Cheers, Bill

Offline a10t2

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #1 on: March 06, 2011, 12:05:07 PM »
Is the tank jacketed? Is it a conical? Is there a side port, or do you have to pull from the bottom? Are you filtering?

Typically in the States, where the answer to all four questions would be yes, you would drop the yeast once it reaches FG, dry-hop for a few days, then cold crash for a few days and rack off of the side port.

Are you really only going to take 10 hL from a 20 hL batch, and dump the rest?
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Offline tschmidlin

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #2 on: March 06, 2011, 02:19:18 PM »
See if there is some way to suspend the hops in the fermenter.  You can get a big nylon mesh bag of some sort that you can fill with the hops.  Sanitize the bag, throw the hops in, tie it shut and tie it to something that will allow it to be suspended in the beer but above the port, and toss the bag into the fermenter.  You can add some stainless parts to the bag to help it sink.

You must be excited to taste the beer, let us know how it turns out!
Tom Schmidlin

Offline tubercle

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #3 on: March 06, 2011, 03:52:40 PM »
 Pillow cases....1 per pound ;)
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Offline majorvices

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #4 on: March 06, 2011, 05:49:22 PM »
How large is the port opening? If it is 2 inches or larger you should be able to dump the hops no problem. If it gets a little clogged just add some co2 pressure to push it through. Personally I would have use pellitized hops.
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Offline wamille

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #5 on: March 06, 2011, 10:37:45 PM »
Addressing a few issues... the fermenter holding the IPA is 20 hecto-liters, but the batch is only 11 hecto-liters total.  It just so happens the brewery's main fermenter is rougly twice the size of the batch.  The fermenter has one opening and it's on the top... perhaps an 18-inch round opening.  It has two dump valves facing opposite one another at the bottom.  The tank is conical shaped.  There is no filter for this particular fermenter - so I've been told.  I have access to pellet hops... would they be better?  I believe the brewers have some at least one mesh bag that could be used for dry hopping if I go with the leaf hops... I just don't know how many bags they have.  I know one of the mesh bags holds at least 2 lbs of leaf hops.  As far as weighting the bags down (assuming we follow that course of action), we'd have to tie them off at the top in order to retrieve them.  Actually, they'd have to be tied off regardless, so weighting them isn't really an issue.  The fermenter is about 20 feet tall with only the one opening at the top.  It does have the ability to keep the beer temperature constant with two pipes running into it for hot and cold water.  But as I'm new to commercial brewing, I don't know much more about the functioning of this fermenter.  The fermenter has no side port... well, only big enough to pour into a hydrometer.  You can't hook up a hose to this tiny, tiny little port.

Regarding the gravity... so I should wait until the beer is at it's final gravity before dry-hopping?  I thought it was acceptable to add them when the fermentation was almost complete - like around 1.020.  I want the hop aroma and taste to be as much as it can be.

Offline tschmidlin

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #6 on: March 06, 2011, 11:08:26 PM »
I would wait until it was done to dry hop because that's what I always do, someone else may have better justification (like the sedimenting yeast pulling hop flavors out of the beer perhaps).  If you have to tie it off anyway, then tie it so it won't interfere with the outlets.  Throw a chunk of stainless in the bag with the hops, I don't know what kind of fittings they use but a loose tri-clover fitting or a stainless pipe elbow would work well.  If you don't have anything appropriate, don't worry about it.
Tom Schmidlin

Offline wamille

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #7 on: March 07, 2011, 12:03:33 AM »
Tom... thanks for the last bit of info.  I imagine they have plenty of the tri-clamps to spare and one should be heavy enough to suspend the hop bag into the beer.  I'll inform the brewers to wait until the beer is done to add the dry hops.  I imagine giving the hops 5 - 7 days in the fermenter is sufficient before we transfer it into the bright tank.  My only question is the sanitization of the cord that will be holding the hop bag(s).  Part of the cord will be outside the tank... how do you keep it free of bacteria?  I'm guessing spraying it with sanitizer once a day would work? 

Offline tschmidlin

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #8 on: March 07, 2011, 01:28:49 AM »
I wouldn't worry about the part that is hanging out of the tank, as long as you're sure it won't end up in the beer.  But if it concerns you, dosing it with sanitizer won't hurt.

I'm thirsty.
Tom Schmidlin

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #9 on: March 07, 2011, 06:23:05 AM »
I dry hop in my brewery with hop pellets and only have a 1 inch port and I am able to dump the hops no problem in my bright tank. I have dry hopped in my conicals as well ith pellets and never had a problem racking the bee.
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Offline wamille

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #10 on: March 07, 2011, 08:21:06 AM »
maj... none of us north americans have ever brewed with equipment of this scale.  i just don't want to ruin a metric ton of beer if i can avoid it.  the korean brewers have no clue about hops... particularly dry-hopping.  if we start making a regular offering of ipa, i'll see about pellet hops for dry hopping.  by the way, does anyone know where i might find a picture or article on a fermenter filter?

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Re: Adding Dry-hops to Commercial-sized Fermenter... best method?
« Reply #11 on: March 07, 2011, 08:38:00 AM »
Well, if you are in a conical the hops will fall to the botttom and if the port is large enough, and especially if the conical is presssurizable, you should be able to just dump the whole hops and then rack the beer. I know for a fact you wouldn't have a problem with hop pellets.

On my set up I normally dry hop with pellets but when I have used whole hops I just put the hops in large mesh sacks. In the conical I just dump from the bottom port. On my bright tanks I have 2 ports, one on the very bottom, and I just dump them from the bottom port and rack off clean beer.

The beers I have dry hopped in my bright tanks, or conicals, have never had any problems with hops being in the beer by the time they were racked to kegs. I think if you follow one of the above methods you will be fine. If you are still concerned I would recommend posting your question on www.probrewer.com
Keith Y.
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