Dry Hopping: keg hop? Magnets?

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mattman91

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So, I'm thinking about finally making a NEIPA. The thing that has scared me most has been fear of oxidation. I do closed loop transfers from my Fermonster, but dry hopping is what I have feared lately.

My idea right now is to dry hop on day 3 of fermentation for biotransformation and the added bonus of active fermentation pushing oxygen out. I would still like to do a traditional dry hop at the end of fermentation, but at that stage I do not want to open the top of my Fermonster.

I have thought about using a muslin bag and a set of magnets to drop the hops without having to open the lid, but I feel like hops being in a 65 degree environment out of liquid for 6-7 days probably isn't ideal.

I have heard of people adding dry hops directly to the keg before filling. Has anyone had any luck with this? I have read that some people say that it can make the beer grassy if the hops are touching the beer for too long. Makes sense, but I brew 2.5 and 3 gallon batches, so my beer doesn't last more than 3-4 weeks usually.

Any suggestions? Is the day 3 dry hop enough if I use enough hops? Any real added benefit of the second addition?
 

Jag75

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Since you use kegs I'd just dry hop 3 - 5 days prior to kegging . I do it all the time with no issues. I just run co2 at 2 psi while I'm adding the hops.
 

AlexKay

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I would not immerse a rare-earth magnet in beer that I wanted to drink. No telling whether or how much would leach out, and the health effects of the metals aren’t really known (and probably not at all good.)

If I were going that route, a strong magnet in the outside and some 400-series stainless on the inside is what I would do. Ball bearings, maybe.
 

Jag75

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If your dead set on not opening to dry hop then I would use fishing line before I'd drop a magnet in my beer.

Just run a line up through the airlock and tie off or make a not so it won't drop into the beer. Then when your ready cut the line and your hops will drop.
 

DuncB

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I use a normal magnet in 2 layers of vacuum sealed bag. This is stitched into a pocket in the side of the net curtain bag.
I tend to put two bags in at the start of ferment into the fermzilla. I use rare earth magnets salvaged from hard disk drives on the outside.

Not had a problem with the hops hanging around in the top of the fermenter ( hops are bad for bugs) .
Last brew was a philly sour then kveik ipa, open ferment under airlock first 5 days at 26 celsius then dropped some kveik flakes in and sealed up with spunding valve raised temp to 33.
Slid the first hops in at 1.020 and then when final gravity occurred a few days later, cooled to 14 celsius and slid in second dry hops.

If the hops are kept magneted you can swish them around.

After 5 days cold crashed and raised the hops out of the beer, then after a week cold crashing and conditioning a closed transfer.
IMG_20210710_185907.jpg


If I hadn't been using the kveik I wouldn't have opened to drop the flakes in.
But I could have rehydrated the flakes and done a closed injection of the yeast but couldn't see the need.

I only really notice the hop aroma in the brew room once the hops go into the beer not whilst dangling.
 

DarrellQ

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FWIW, the magnets do not need to go in the muslin bags. You can put a large washer in a small zip lock bag inside the muslin bag with the hops. Thus the magnet needs to only be the outside of the carboy. I have thought many times of using this technique but so far have just put about 3 psi of Co2 through the dip tube port as I'm adding the hops. I haven't detected any issues with oxygenation.
 

d_k_8

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re: magnets for dry hopping

I recently saw these sous vide magnets that have a food-safe silicone coating. planning to get a few to try out in my next batch.

 

RampantOctopus

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re: magnets for dry hopping

I recently saw these sous vide magnets that have a food-safe silicone coating. planning to get a few to try out in my next batch.

Expensive but nice. Hopefully they get popular enough for the prices to come down.
 

RampantOctopus

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Jim R

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Vacuum bag material works well to seal the edges around the magnets. They can be easily sealed with a household iron without buying an expensive vacuum sealer.

I tried the fish line trick with my Fermzilla All Rounder. I used a very small diameter fishing line but even that broke the seal of the rubber gasket on the top cover and it wouldn’t hold pressure. That was a fail.
 

hotbeer

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geez! I just pulled the stopper out of my fermenter and dropped the hops in on day 4 and day 16 of my first NEIPA's ferment.

I'm not expecting it to be the greatest, but I don't expect it'll be bad either.

Should I worry? I'll be opening the first bottle tomorrow to see how it tastes.
 

gello22

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I have had long lasting neipas from the fishing line in trick though the top of a bucket fermenter. I actually just drilled two small holes with a circuit board drill 1/32 maybe, to run the line through and taped the holes shut.

when I switched to a pressure fermenter I used the magnets in the vacuum sealed bag. The one nice thing about the vacuum seal is if you do it a couple days in advance you will know if it leaks by losing vacuum. They are either a PITA to clean or you do new magnet bags each time.

Now I use the sous-vide magnets inside and bare neodymium magnets outside. I keep my hops in the bags, but they could be placed vertical in something like the snubnose that has large vertical head space leaving the top of the bag open and drop the top magnet first allowing the hops to commando.
 

Jim R

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They are either a PITA to clean or you do new magnet bags each time.

I sealed my magnets in vacuum bag material that is just slightly bigger than the magnets themselves. I sealed the vacuum bags with my wife's clothes iron. I place these inside a disposable muslin mesh bag (80 cents each) that hold the hops and just use new mesh bags each time. There is nothing to clean and sanitize afterwards except the outside of the small magnet vacuum bags which takes about 30 seconds.
 

gello22

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I sealed my magnets in vacuum bag material that is just slightly bigger than the magnets themselves. I sealed the vacuum bags with my wife's clothes iron. I place these inside a disposable muslin mesh bag (80 cents each) that hold the hops and just use new mesh bags each time. There is nothing to clean and sanitize afterwards except the outside of the small magnet vacuum bags which takes about 30 seconds.
My language wasn't very clear, typical of engineers. I was whining:) about cleaning the seams and texture on the vacuum sealed magnet bags. I toss the muslin bags too.
 

DuncB

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I just put the vacuum bags in some warm not hot pbw along with the bags after a good rinse. Not finding that a problem although I did make the bags out of net curtain type material so they clean up well and are nice and leaky.
 

lcram

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I tried this method out yesterday brewing a NEIPA. I put a sous vide magnet (covered in food-grade silicon) into a sanitized (boiled) hop bag along with a 3oz dry hop and tied it off. Stuck that to the inside of the fermonster lid. This worked great.

THEN I tried doing the same thing for a second dry hop with 5oz of hops. It held for a second then dropped the whole hop bag into the wort. I quickly fished it back out with a sanitized spoon, but wouldn't call it a "dry" hop anymore :( I untied it and added another magnet to hold it steady. I'll drop the first bag at 2 days and the next at 9.

Anyway - BE CAREFUL when doing this and make sure you have enough magnets to hold your dry hops steady while moving fermenter, etc. Was a bummer to get through 95% of the brewday and have such a dumb mistake in the last few minutes. Would love to hear any thoughts as to how a quick dunking might affect the second dry hop.
 

DuncB

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@icram
I've just ordered some of those sous vide magnets for inside the bags of hops. I do use the harddrive magnets on the outside and they are very very strong. Sometimes several small bags needed to manage the dangle. My early trials the krausen rose and then got on the hops in the bag, they got wet and heavier and fell in. I fished them out and spilt the hops between 2 bags.
I'll do some weight failure tests when my sous vide magnets arrive so I have an idea of how much they can hold up.
 

CascadesBrewer

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stir bars make excellent food safe magnets. Just sayin.

After my first try with the magnets directly in the beer, I picked up a pair of stir bar magnets. They seem good in theory, but I found that the grip with stir bar magnets is VERY weak. I am not exactly sure how stir bar magnets are constructed, but one end attracts to the magnet and the other end repels. The rare earth magnets that I have are very strong (they are very hard to get apart).

The sous vide magnets are probably fine. I have seen some that say they are "food grade". I do notice that they are not designed to go inside the bag with direct food contact.

I think next time I will try to vacuum seal some magnets. I am curious about using an iron, as I don't have a vacuum sealer myself.
 

Teufelhunde

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geez! I just pulled the stopper out of my fermenter and dropped the hops in on day 4 and day 16 of my first NEIPA's ferment.

I'm not expecting it to be the greatest, but I don't expect it'll be bad either.

Should I worry? I'll be opening the first bottle tomorrow to see how it tastes.

I think there might be some overthinking/overworrying going on here. I have done several NEIPA's in Plastic buckets. I open the bucket to put in both the 1st and the second dry hop. When I bottle, I transfer to a bottling bucket. Never an issue with oxidation. That being said, my beers don't sit around for six months either. They tend to be gone by 4 weeks after being bottled......

YMMV

Lon
 

DuncB

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@CascadesBrewer
I've been using the rare earth on the outside taken from PC hard drives and normal ferrous magnets on the inside in the vac seal bags.
I think the iron will work fine might be best to have some cloth between the iron and the plastic. You will be able to get a smaller packaged for the magnet made your way as the vac seal machines have constraints with dimension due to the way they work. Well mine is limited to about 3 inch at the narrowest.
It's a shame that heat shrink tubing doesn't seal to itself and isn't food safe.
 

Elric

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@CascadesBrewer
I've been using the rare earth on the outside taken from PC hard drives and normal ferrous magnets on the inside in the vac seal bags.
I think the iron will work fine might be best to have some cloth between the iron and the plastic. You will be able to get a smaller packaged for the magnet made your way as the vac seal machines have constraints with dimension due to the way they work. Well mine is limited to about 3 inch at the narrowest.
It's a shame that heat shrink tubing doesn't seal to itself and isn't food safe.
Vacuum the bag to whatever minimum dimensions it needs to suck out air. Once you have successfully created the seal use just the sealing function on the already vacuumed bag to creat a full seal just around your magnet and cut the rest of the bag away. heck, as long as you have pushed out most of the air, you really don't need to make a vacuum at all, you just need the magnet fully sealed. I use rare earth magnets on both sides for the highest strength attraction so that little bumps or heavy hops won't send the bag flying. This way I can also pull the fully soaked hop bag back out if/when I want to as well (i.e wanting three days hop contact time but wanting more days cold crashing before kegging the beer).
 

DuncB

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@Elric
You are right about cropping the bag smaller, I must have done this but forgot that I did it. I tried a rare earth hard drive magnet on the inside and outside but it was so " attractive" I could hardly move them. Strong on outside and weaker on the inside is working for me at present. Although I'll await the sous vide magnets to see if they are a good internal choice. But l agree being able to put the hops in, swish them about in the bag under magnet control and then take them out whilst cold crashing is a real benefit.
 

BongoYodeler

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Vacuum the bag to whatever minimum dimensions it needs to suck out air. Once you have successfully created the seal use just the sealing function on the already vacuumed bag to creat a full seal just around your magnet and cut the rest of the bag away. heck, as long as you have pushed out most of the air, you really don't need to make a vacuum at all, you just need the magnet fully sealed. I use rare earth magnets on both sides for the highest strength attraction so that little bumps or heavy hops won't send the bag flying. This way I can also pull the fully soaked hop bag back out if/when I want to as well (i.e wanting three days hop contact time but wanting more days cold crashing before kegging the beer).
This is what I do.
 
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