Freezing Hops. Do or don't?

In another thread the topic of freezing whole hops came up. Being familiar with a very similar oil gland containing flower and the detriment to the glands and overall quality and potency of the flower that freezing causes I was surprised to hear that it is common for homebrewers to freeze their whole hops.

Doing some reading on the topic I came across a post outside of this site that eludes to this not being a very big deal when it comes to bittering hops but will effect the aroma hops as the freezing causes the glands to rupture and the oils boil off before they have a chance to oxidize and become soluble.

Am I simply over thinking this or is there something to rupturing the oil glands that most of you don't concern yourselves with?

BendBrewer said:

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Doing some reading on the topic I came across a post outside of this site that eludes to this not being a very big deal when it comes to bittering hops but will effect the aroma hops as the freezing causes the glands to rupture and the oils boil off before they have a chance to oxidize and become soluble.

Am I simply over thinking this or is there something to rupturing the oil glands that most of you don't concern yourselves with?

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Considering the hop flowers are pulverized when put into pellet form I'm going to guess there isn't any harm in rupturing the oil glands.

Do freeze your hops. The hop qualities degrade slower at lower temperatures.

NorCalAngler said:

Considering the hop flowers are pulverized when put into pellet form I'm going to guess there isn't any harm in rupturing the oil glands.

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The post also mentioned pellets and the process of rupturing the glands to make them and hence why they aren't the best option for aroma additions.

http://www.practicalbrewing.co.uk/forum/viewtopic.php?f=14&t=86

It seems certain that the freezing of hops will rupture the glands. My limited experiments to prove / disprove this have been inconclusive due to not having enough hop samples and not checking them to see if they were ruptured before I put them in the freezer. I need to do more experiments with proper controls, but I am tied up writing my book. Hop merchants do not freeze whole hops, but it seems that home brewers have not picked up on this. Googling just now, I can only find one reference to it in home brewing, but only one line at the very bottom of THIS page and even then the author of the page doesn't seem to believe it. One thing is certain though, and that is that if the glands do rupture during freezing they will oxidise very rapidly once they come out of the freezer. The encapsulated protective effect of the glands is lost. They are best kept frozen in this case.

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You do what you want but I will continue to follow the Grocery Store rule of storing.

Store it how you bought it. Now go take those tomatoes out of the fridge. You are ruining them.

Haha. Tomatoes in the fridge are a sin. I am storing my hops in the freezer though. I have pellet hops, vacuum sealed, in a glass container.

I'll let you know how my beer tastes.

BendBrewer said:

You do what you want but I will continue to follow the Grocery Store rule of storing.

Store it how you bought it. Now go take those tomatoes out of the fridge. You are ruining them.

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My LHBS freezes their whole hops too. Seriously though, I'd be all for keeping them as fresh as possible, but given the limited harvesting season at some point you're going to be using hops that are almost a year old. At some point the harm to the oil glands is going to be overridden by the loss of stability from NOT freezing them. At least I think so. I'd be more than happy to hear viable alternatives for maintaining freshness in a way that's less harmful to the hops.

Ben_Persitz said:

Haha. Tomatoes in the fridge are a sin. I am storing my hops in the freezer though. I have pellet hops, vacuum sealed, in a glass container.

I'll let you know how my beer tastes.

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It won't effect pellets as the pellets have already had their glands ruptured.

I dunno. I have nothing to offer - except a " I did this once " story.

I got 5 oz of Cascades from Homercidal, that had been vac sealed and frozen on his end, and after a while pulled out of the freezer and sent to me thanks to the Pay It Forward Thread. When I got them, I left the bag out on my desk ( accidentally ) for about 5 days, and then uponed them up. They were like baled , um, buds. Yeah.

Anyway - pulled them aprt, they fluffed up, smelled AMAZING - and dry hopped with the bad boys. The result - dunno - will tell you in a couple weeks when the beer is carbed up. But the bottle aroma from those two batches is killer.

BendBrewer said:

The post also mentioned pellets and the process of rupturing the glands to make them and hence why they aren't the best option for aroma additions.

http://www.practicalbrewing.co.uk/forum/viewtopic.php?f=14&t=86

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The claim "They are not very good at aroma." referring to pellet hops is a pretty bold claim considering there are thousands of test cases out there where pellet hops dry hop just fine after being frozen and not oxidized. The IPA I just bottled Monday disagrees with this assertion as well. Perhaps the poster misunderstands the mechanics of the compounds in hops and how they release into beer?

I don't know, I used to freeze my buds. Other than getting dried out, I never noticed a huge decrease in potency or flavor.

Did a quick search...there are far more proponents for storing them in the coldest possible temp vs. storing them at refrigerator temps:

From this site - http://www.brewingtechniques.com/library/backissues/issue2.1/garetz.html

Hops start to lose their a-acids and oils as soon as they are harvested. The rate of loss depends on the storage temperature, the amount of air present, and the hop variety. The lower the temperature, the less the hops deteriorate. It has been shown that the rate of loss halves for every 15 degrees C (27 degrees F) drop in temperature (2).

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For optimum preservation of hops' valued qualities, they should be stored as cold as possible (30 to -5 degrees F, or -1 to -21 degrees C) and away from air.

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Then this site (I'm sure you would count as a trusted source)- http://***********/stories/wizard/a...u-store-hop-pellets-to-extend-their-freshness

storing hops at freezer temperatures does extend their life and will not damage the hops. How can I be so definitive, one may ask? Because when hop processors store hops, they store them at temperatures ranging from 20–30° F...

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Both sites detail storing them and WHY you would store them as such. However, to summarize, the idea is to keep your hops away from oxygen to prevent oxidation. Vaccuum sealing accomplishes this. And cold storage helps as well.

so likely vaccuum sealed at room temp is better than ziplock bags in the freezer?

I exclusively use whole hops for bittering and aroma in my kettle, hop back, and dry hop. I vacuum seal and freeze them for storage. I've always been pleased with the aroma I get. Then again, I love to hop burst and throw four ounces in at the end of the boil.

BendBrewer said:

The post also mentioned pellets and the process of rupturing the glands to make them and hence why they aren't the best option for aroma additions.

http://www.practicalbrewing.co.uk/forum/viewtopic.php?f=14&t=86

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Seems to me that the post is assuming fresh whole hops vs the dehydrated whole hops. The poster says he doesn't have too many samples from which to draw conclusions (so I assume there's even less data for fresh hops vs packaged vs pellets). Having some background in biology, I know I wouldn't care about whether the gland is intact or not by the time I buy the hops in GA. If I was picking the hop fresh from the farmer, then that might be a different story (the only local hop growers I know about can only grow a few styles in the SE). Still an interesting thing: what compounds are most important for aroma: that's the main issue. The only thing I've heard is that not storing your hops in a sealed, cool area is that it reduces alpha acids (so I'd assume that is the main compound for good bitterness). As for my methods, I'm not holding on to my hops that long, so I just keep them sealed and in the fridge. When I do a quick google of hop aroma compounds, I don't seem to get anything definitive (especially in regards to preservation of oils with fresh vs processed hops).

Some interesting links:
http://www.realbeer.com/hops/aroma.html

http://www.mbaa.com/emergingIssues/pdfs/Linalool.pdf

BendBrewer said:

The post also mentioned pellets and the process of rupturing the glands to make them and hence why they aren't the best option for aroma additions.

http://www.practicalbrewing.co.uk/forum/viewtopic.php?f=14&t=86

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Hmmm, does it say anywhere what the effects are of ruptured vs. non-ruptured glands? Without assuming anything?

AZ_IPA said:

so likely vaccuum sealed at room temp is better than ziplock bags in the freezer?

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Depends on how you use your hops I would say. If you use them quickly and the hops aging doesn't matter then vaccuum sealed at room temp would be better in my mind. Everything I'm reading indicates that the mortal enemy of the hop is oxygen. So the first goal is eliminating that. At least that's what I am understanding. However, just so we are clear, I advocate the freezer method. I am no expert though.

Ben_Persitz said:

Haha. Tomatoes in the fridge are a sin. I am storing my hops in the freezer though. I have pellet hops, vacuum sealed, in a glass container.

I'll let you know how my beer tastes.

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I still like to refrigerate some of the tomatoes, so they'll keep longer... Better bland than moldy.

Does that somehow parlay into the hop storage issue?

Direct from a respected and large hop processor that supplies to a lot of micros: "In your freezer is the best place frost free in a bag the seals well, try not to let them get wet or warm up and cool down over and over, they will loose alpha each time. But 24 degrees or below is the best."

I hope there's nothing impolite about waking up an old thread... but I am still looking for a definite answer to the question of whether to freeze, and don't have the answer myself. I've become interested since starting to think about growing my own hops, which, it seems to me, would end up resulting in having to store more hops at a time (at least for part of the year).

I doubt I know more about hop stability than Ben does, and I'm sure I don't know more about it than a "respected and large hop processor," but just to throw in an apparently opposed point of view: Ted Goldammer writes in "The Brewer's Handbook" that "For optimum preservation, hops should be stored at temperatures between 0C and 2C." This differs from the assertion that 24F or below is best. Goldammer's not in the hops business, like the hops processor, but then again he's writing for professional brewers and probably taking his knowledge from the experience of professional brewers.

Is there just a difference of opinion among people very qualified to answer the question? Or, could it be that people with different answers to the question are imagining different storage durations? Does storage duration have anything to do with the optimal storage temperature?

Thanks for any help.

One thing is for sure, hops don't stop providing good aroma after they've been frozen. If the aroma is not as good as it could have been is debatable, and I suspect if there is a difference it is very small.

I bought a pound of Nugget hops a few months ago on sale. What I haven't used has kept just fine in the freezer. I've noticed very little to no deterioration in flavor or aroma.

EDIT: I should also mention, it is important to eliminate as much air as possible from the plastic bag or whatever you are using to store your hops.

Most of the degradation that occurs, ruining hops, are chemical reactions of sorts. These reactions are subject to the generalized Arrhenius equation; every 10°C increase in temperature, doubles the reaction rate.

I don't remember which episode it was, but I think one of the Brew Strongs talked about this subject in depth. The conclusion was that hops stored, sealed, in a constant frozen state will store fine for years with only minimal degradation. On the other hand, hops stored at room temperature become worthless in a matter of weeks.

All this talk of ruptured glands, I thought I was in the wrong place.

I have frozen whole hops before, but mostly just keep them in the fridge.

I am going to try freezing some and drying some and maybe brew to 1/2 batches Next winter and see if there is a difference, Being a bit of a prepper I have a vacuum sealer that seals up to quart, jars, so I may blanch the hops, freeze them then pout them in a jar and vacuum seal it, the dried ones I will just vacuum seal. This way I can just use used jelly jars an such

I will let you know what I find next winter.

This was a 10 year old thread... What do you mean by blanching? There is no "other way" to handle hops for homebrewers as this thread wants to suggest. Either you get them from the farm (which has dried and stored them cold until sale) and use them right away or you get them and store for use later. Best as cold as possible. Hop pellet machines are operated at sub-zero temps to protect the hops. Cold is not bad for these things if you can not use them right away. Oxygen is the main problem.

I vacuum seal them in mason jars and keep in the freezer as it is convenient. The best would be to vacuum seal in oxygen proof bags but they are more expensive than mason jars and single use.