Help with IPA flavour stability.

[khillian]

I need help with keeping my IPA's fresh and from losing flavour within 2 weeks.
After carbonating in the keg for a week they taste magic but then as time goes on they start to get less and less flavourful with only the bitterness still being pronounced. After 3 weeks or so they are almost like a bitter.

I brew 5 gallons and do a primary only fermentation in a 8 gallon (30L) Speidel fermenter then dry hop and rack to a purged keg. I am sure that my gear is clean and sanitized and I check mash pH with a pH meter. My water is very soft and is good drinking water. I add 2-3 gr of gypsum.

My guess is oxidization but the frustrating thing is that I don't know how I can reduce it as I purge everything before racking and purge the keg after.
I am wondering if a smaller fermenter would help?

Back to the OP, this sounds like oxidation. I think we all agree. Try and reduce oxygen at every step post fermentation, I hope some of this discussion has proven useful. Again none of these are smoking guns, you can make great beer with/without any of this, but I think any/all of these will help reduce oxygen which should make a more stable product.

1. Quick fermentations (9-12 days in primary for most healthy ferments) that will keep those whirl pool aromas and flavors alive. Letting your beer sit in primary at 70F for 3 weeks is going to undo all that hard work.

2. Moving beer from primary to keg
If your good with auto siphons then scratch the spigot idea, but I for one suck. Purge all kegs before and after filling. I personally don't like cold crashing, especially if you transfer the beer cold, ie. colder liquids hold more gas, ie. oxygen will absorb more readily. The suck back via the airlock is also real and will diffuse oxygen into the headspace (none of this bull**** c02 is more heavy then air, I guess in NYC you would pass out if you laid down on the floor due to all that heavy c02). I only cold crash in kegs which can be purged and fed c02 as chilling creates a vacuum.

3. Dry Hopping
Dry hopping towards the end of primary will reduce any oxygen in the hop pellets or leaf. The yeast will actually uptake the oxygen and also transform some of the hop compounds into good aromas. For my bigger beers the second round in the keg via bag also has more more live yeast then a cold crashed beer to protect against some oxygen. If you had cold crashed, transferred cold, added more hops, the colder beer as it warms up will begin to oxidize for sure.

4. Post Dry Hopping
Keep the beer as cold as possible. If the keg is opened for any reason, re purge the headspace 4x at 15psi.

You have 4 parts other stuff (mostly N2), and 1 part air at atmospheric pressure, approximate to 15 PSI. If you put 30 PSI on the keg, you have added 2 times the stuff, or 10 more parts. So the gas mix is 1/15 O2. Vent and repeat 2 more times.

You will have reduced to 1/(15^3), and that comes out to 0.00029 parts O2 left, which is pretty small.

I you want to use 15 PSI, you do it 3 times you are at 0.001 parts left.

4 times at 15 PSI gets you to 0.0001.
^^^ People call me crazy, but this math works out.

Some other links of people who agree,
http://www.bertusbrewery.com/2014/12/micro-pale-ale-30.html
"I dry hopped this directly in the primary while there was still some yeast activity. I'm starting to find that minimizing oxidation outweighs hop/yeast contact. This is pretty much the reverse from what my mindset was a couple years ago. For my IPAs and DIPAs, I still rack the beer into a keg to dry hop, but for low gravity IPAs and Pale Ales, I'm dry hopping in the primary to take advantage of the oxygen-scavenging properties of active yeast. Anyway, the dry hops went in day 6, and I chilled the primary and kegged the beer on day 13."

http://www.bear-flavored.com/2014/09/how-i-dry-hop-my-ipas-with-no-oxygen.html
Here's the basic theory behind this: oxygen is very bad for hops. When I was bottling my IPAs, no matter how good the recipe or how well-managed the fermentation, they would always drop off very, very quickly. The better you can prevent O2 from infiltrating your beer, the better chance the hop character has to preserve its awesomeness

Brew on OP, and check back with us after a few more batches, I think you will be back on the Hop Bus to Hop City.

 

[D-Train]

Do you connect your tubing to a ball lock connector to get the beer in the keg?
Does it work ok backwards?

I keg in sankes and have a spare coupler. I connect tubing to the "liquid out" with the check valve removed. I then fill in the liquid out. I reversed the "gas in" check valve so that it can bleed co2 as it's filled.

I essentially followed this article but adapted it to sanke kegs, and replaced step 1 with a true purge using starsan:
http://www.metabrewing.com/2014/08/avoiding-oxygen-when-kegging-co2.html

Edit: You want to fill in the liquid side, so that the beer runs down the liquid post and fills from the bottom to avoid agitation. I actually tipped the keg 45 degrees for awhile just to encourage as little agitation as possible.

 

[DrunkleJon]

Do you connect your tubing to a ball lock connector to get the beer in the keg?
Does it work ok backwards?

I keg in sankes and have a spare coupler. I connect tubing to the "liquid out" with the check valve removed. I then fill in the liquid out. I reversed the "gas in" check valve so that it can bleed co2 as it's filled.

I essentially followed this article but adapted it to sanke kegs, and replaced step 1 with a true purge using starsan:
http://www.metabrewing.com/2014/08/avoiding-oxygen-when-kegging-co2.html

Edit: You want to fill in the liquid side, so that the beer runs down the liquid post and fills from the bottom to avoid agitation. I actually tipped the keg 45 degrees for awhile just to encourage as little agitation as possible.

I tend to do the same thing. Though I dont bother with removing the poppit. I just screw a Beer out quick disconnect into the tip of the racking hose and throw a gas in quick disconnect on the gas side (add in a keg jumper if I am doing a 10 gallon batch, and have a three tier siphon going) with an open gas connector at the last gas post. Start the siphon and let her go until I come close to the trub layer. Then unhook the beer connector to stop the flow or move on to second fermenter.

 

[Gnomebrewer]

(none of this bull**** c02 is more heavy then air, I guess in NYC you would pass out if you laid down on the floor due to all that heavy c02).

It is interesting (well I think so) that it was Pliny the Younger who survived and wrote about the 79AD eruption of Mt Vesuvius which killed many, including his Uncle (interesting because of the beer link to Russian River). I think all those who died in the eruption, and many who have died in other volcanic eruptions would say that you are sprouting bull**** (well, actually they won't, because they're dead). It is mostly a layer of CO2 (which IS heavier than air and O2) blanketing the ground that kills after a volcano.

The math side: Carbon has a mass of approximately 12AMU's, Nitrogen 14AMU's and Oxygen 16AMU's, thus 1mol of CO2 has a mass of approximately 44g, O2 32g and N2 28g. Gas volume depends on the number of molecules, not mass, therefore at the same pressure CO2 is heavier than air.

However, gases behave a little bit like liquids when mixed....they don't tend to have the heavier ones sink. Like cordial concentrate (heavier than water) mixed into a glass of water makes a consistently mixed drink. So in air, the gases mix together quite well. But, if you squirt pure CO2 into a container, a lot of it tends to sink. It's not perfect, there will be some mixing, but it works quite well. If you don't believe me, try putting some lit candles on shelves at different heights in a very small room or large container and squirt CO2 in - the lower candles will be extinguished first.

 

[khillian]

It is interesting (well I think so) that it was Pliny the Younger who survived and wrote about the 79AD eruption of Mt Vesuvius which killed many, including his Uncle (interesting because of the beer link to Russian River). I think all those who died in the eruption, and many who have died in other volcanic eruptions would say that you are sprouting bull**** (well, actually they won't, because they're dead). It is mostly a layer of CO2 (which IS heavier than air and O2) blanketing the ground that kills after a volcano.

The math side: Carbon has a mass of approximately 12AMU's, Nitrogen 14AMU's and Oxygen 16AMU's, thus 1mol of CO2 has a mass of approximately 44g, O2 32g and N2 28g. Gas volume depends on the number of molecules, not mass, therefore at the same pressure CO2 is heavier than air.

However, gases behave a little bit like liquids when mixed....they don't tend to have the heavier ones sink. Like cordial concentrate (heavier than water) mixed into a glass of water makes a consistently mixed drink. So in air, the gases mix together quite well. But, if you squirt pure CO2 into a container, a lot of it tends to sink. It's not perfect, there will be some mixing, but it works quite well. If you don't believe me, try putting some lit candles on shelves at different heights in a very small room or large container and squirt CO2 in - the lower candles will be extinguished first.

Agreed, flushing with co2 is a great solution. I quoted Vinny from Russian River earlier, he thinks a co2 tank for flushing is a must have even for the non kegging folk. Many on this forum seem to think the residual co2 created during fermentation is like a blanket forever protecting the beer. If you cold crash you would be pulling in oxygen, if your racking is messy, and then you warm it back up to dry hop for a week, this would accelerate oxidative reactions.

 

[beerkench]

Agreed, flushing with co2 is a great solution. I quoted Vinny from Russian River earlier, he thinks a co2 tank for flushing is a must have even for the non kegging folk. Many on this forum seem to think the residual co2 created during fermentation is like a blanket forever protecting the beer. If you cold crash you would be pulling in oxygen, if you racking is messy, and then you warm it back up to dry hop, this would accelerate oxidative reactions.

Some of the cask ale pubs use cask breathers, a valve that pulls co2 at atmospheric pressure into the cask when beer is drawn from it (Cask being slightly carbonated they don't want to carbonate it any more).
I'm surprised that there isn't such a device for our fermenters. And if there is such a device, I'm surprised they aren't more available. It would be ideal for cold conditioning.

Khillian, one more question: I find that cold crashing after dry hopping paints the hops to the bottom of the bucket making siphoning a bright beer easy. How do you manage to draw off beer from the spigot with the hops still floating without it getting messy?

 

[khillian]

Some of the cask ale pubs use cask breathers, a valve that pulls co2 at atmospheric pressure into the cask when beer is drawn from it (Cask being slightly carbonated they don't want to carbonate it any more).
I'm surprised that there isn't such a device for our fermenters. And if there is such a device, I'm surprised they aren't more available. It would be ideal for cold conditioning.

Khillian, one more question: I find that cold crashing after dry hopping paints the hops to the bottom of the bucket making siphoning a bright beer easy. How do you manage to draw off beer from the spigot with the hops still floating without it getting messy?

I tend to use only up to 2oz in primary to keep things less messy. Move the bucket into place on a table from the fermentation chamber at least 8 hours before I intend on racking the beer to a keg. I also put a wedge under the side opposite the spigot. Once you begin racking I have a bright light to check the level of falling beer in the bucket. Most of the pellets sink but some are on the top floating still, the key is to turn off the spigot once your near that top floating level.

 

[beerkench]

I tend to use only up to 2oz in primary to keep things less messy. Move the bucket into place on a table from the fermentation chamber at least 8 hours before I intend on racking the beer to a keg. I also put a wedge under the side opposite the spigot. Once you begin racking I have a bright light to check the level of falling beer in the bucket. Most of the pellets sink but some are on the top floating still, the key is to turn off the spigot once your near that top floating level.

Thanks again. I'm going to give this a go although I'm nervous about getting hops into the keg. Nothing worse then pellets stuck in the tube. It's happened to me before and I had to keep taking the tube out and rinsing it. This happened multiple times and it it was at a party too!

Keep us informed in the Longshoot comp.

 

[MadHomebrewer]

I'm about to move to five gallon batches and kegging. Was thinking of going with this fermentor so it can go strait in the keg after cold crashing.

http://www.northernbrewer.com/shop/...iphonless-big-mouth-bubbler-ported-6-5-gallon

 

[khillian]

It is amazing and somewhat disappointing that you can't just lock in the flavor when it gets exactly how you like it. I will sometimes make a hop tea and add it to the keg after a few weeks which helps recharge the hop flavor and aroma.

Yea, I have tried Hop Teas, they have been disappointing. I look to the pros in the industry and try to mimic their techniques. One topic not brought up on this thread is that your hops / supplier do matter. I tend to buy in bulk at time of harvest, 1) to save money buying whole pounds 2) learn that years crop from this supplier to adjust recipes based upon brewing with them 3) if they aren't good try another supplier before giving up on that years crop of a particular variety 4) I have lots of freezer room and a vac sealer. Supplier differences of the same variety can change up a recipe big time, I think many on this forum are bit by this issue often. I contend its not easy to make a Pliny, Heady, etc. quality beer consistently. You have to have good ingredients and a great process.

 

[beerkench]

I tend to use only up to 2oz in primary to keep things less messy. Move the bucket into place on a table from the fermentation chamber at least 8 hours before I intend on racking the beer to a keg. I also put a wedge under the side opposite the spigot. Once you begin racking I have a bright light to check the level of falling beer in the bucket. Most of the pellets sink but some are on the top floating still, the key is to turn off the spigot once your near that top floating level.

Hi Khillian,
So I tried your method and was wondering how the hell you get it to work for you? I racked over to my keg and was watching the tube change colour all the time with different levels of sludge passing through it. I hope it's fine enough to pass through the keg.
Not knocking your method but just can't figure out how to get it to work best. I dry hopped with 2 oz and the hops were throughout the beer. When I cold crash they paint themselves to the bottom.

 

[khillian]

How many days did you dry hop? Did you move the primary into the racking location a while before starting?, also during the 4-5 days of dry hopping I occasionally bump/rouse the bucket. I do get some yeast/particles into the keg but that usually isn't a problem, first couple of pours taste even better with hop particles to me. The only time I have had clogged dip tubes was trying to dry hop loose in a keg with a shortened dip tube.

Good thread on cold crashing / oxidation https://www.homebrewtalk.com/showthread.php?t=494163

 

[beerkench]

How many days did you dry hop? Did you move the primary into the racking location a while before starting?, also during the 4-5 days of dry hopping I occasionally bump/rouse the bucket. I do get some yeast/particles into the keg but that usually isn't a problem, first couple of pours taste even better with hop particles to me. The only time I have had clogged dip tubes was trying to dry hop loose in a keg with a shortened dip tube.

Good thread on cold crashing / oxidation https://www.homebrewtalk.com/showthread.php?t=494163

I'm cold crashing it right now in the keg and I'm hoping all the particles were small and will come out with the first pours. I did have a batch once in which the dip tube kept getting clogged and it was a ****in nightmare!

After you first mentioned not cold crashing in the fv, I Googled and found a Sunday Session podcast where that Jamil guy talks about it too.

I ferment in a Speidels 30L plastic fermenter and they can actually hold some pressure so I'm going to attach a tire valve to the blank cap and swap it out with the airlock after fermentation is finished. I'm then going to cold crash and apply low pressure CO2 via the tire valve. Not sure how it will work but I'm going to give it a try.