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Thread: Coffee myth - freezing coffee

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    Coffee myth - freezing coffee

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    I was going to reply to this comment in the other thread that it was stated in, but thought it may be better to start a separate thread on the myths surrounding coffee.

    DO NOT put your grind or coffee beans in the freezer!!!!!!!!!!!!
    It really annoys me to see statements like this continue to be repeated! Its one of my pet hates! People hear something repeated often enough that they believe it and even repeat it themselves. Much internet spam continues to spread in the same way - you get some email making some sort of claim which sounds credible so you forward it on to your friends to let them know as well, little knowing that you are actually part of the problem of making these myths seem even more credible to others - if many people tell you the same thing, it must be true, right?! If only people would take the time to do a bit of research in to the issue before posting it would help to stop the spread of many of these rumors, myths, etc.

    Scott Rao - The Professional Baristas Handbook, page 78
    Many myths persist regarding the dangers of freezing coffee beans. Do not believe them.
    Freezing works as a long-term storage method because oxidation rates are reduced about fifteen-fold and the coffee oil congeals, greatly reducing the movement of volatiles. Additionally, the scant moisture in roasted beans is bound to the matrix polymer, and therefore nonfreezable.
    And also in the article Coffee: To Freeze or Not to Freeze - Does freezing preserve coffee used for espresso? , by Ken Fox on the Home Barista website, which involved a taste test panel of 3 people blind tasting 64 paired shots of frozen versus never frozen coffee over a 4 day period came to this conclusion:
    When the results were examined according to the three scored parameters, the overall preference, the crema, and the intensity of the taste and aroma, no statistically significant differences were noted among the coffees studied or the other variables of the study. What this means is that none of the tasters could consistently differentiate among the shots made with previously frozen or never frozen coffee.

    Freshly roasted coffee that is immediately frozen after roasting in a near airtight container in a very cold freezer, can be kept undisturbed in the freezer for at least 2 months and be expected to produce espressos that are not obviously inferior to those made from fresh coffee that has never been frozen.
    For the full article, showing all the test procedures and results, refer http://www.home-barista.com/store-coffee-in-freezer.html


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    Senior Member Dennis's Avatar
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    Re: Coffee myth - freezing coffee

    Bill, I agree that a lot of truths are spawned from rumour that often begins with just one persons opinion.

    The quotes youve provided are again, just a few peoples opinion, and Id suggest unscientific. I might in part agree with the first quote, though beginning with the proviso that the freezer would need to be a commercial deep freeze unit.

    Terms like, "near airtight...at least 2 months...not obviously inferior" are far from qualitative or quantative.

    If people are undecided as to whether to store coffee in the freezer, fridge, pantry, or even bury it in a treasure chest, I suggest that they perform their own little experiment with these methods, and come up with their own preference. Until they do so, Ill continue to suggest that coffee is stored in valved bags, in a dark, cool place like the pantry, and not in the fridge or freezer.

    Cheers!

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    Re: Coffee myth - freezing coffee

    Bill,

    Ill second what Dennis said above.....

    There are many experts out there who have a (in their mind at least) perfect argument why something is a certain way.... for ages scientists thought the earth was flat.... and even today some noted historians say the Holocaust didnt happen (try telling that to some Jews who were there at the time!)

    The best answer is to try it yourself and see what you think. I personally dont like the idea, preferring freshly roasted beans stored as Dennis suggested. That works perfectly and I dont see any real need to change. I am suspicious that the coffee will be affected by freezing.... well not so much the freezing but the handling during/after thawing when condensation will occur on the beans etc.....

    Me - I dont have a problem with coffee going stale! But if your requirement is less, then buy smaller quantities - or drink more coffee..... and it wont be an issue one way or the other.....

    But if you want to try - go ahead and try it for yourself..... and if happy with the results - go for it!

    You could be the one who finally proves the earth is round!!

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    Re: Coffee myth - freezing coffee

    Ill third Dennis and second Mal.

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    Re: Coffee myth - freezing coffee

    You know what? I really couldnt care....

    The general "issue" with my coffee is that its often too fresh...

    Im happy to keep it that way and keep my freezer for Gin, Vodka and the like ;)

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    Re: Coffee myth - freezing coffee

    YOU SHOULD NEVER FREEZE GIN!!












    Just kidding.

    If people want to freeze their coffee, they can go for it. Personally, not interested in doing it myself and see no need. Similar problem to Chris in that if I dont plan my roasting well enough, Im drinking stuff that is only +3 days.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by Dennis link=1227707518/0#1 date=1227739356
    The quotes youve provided are again, just a few peoples opinion, and Id suggest unscientific.
    No, not just personal opinion, they have some pretty good evidence to back them up. Thats the difference.

    The thing that really annoys me is people blindly forwarding on info that has NO EVIDENCE to back it up. Just because something is accepted wisdom, does not necessarily mean that it is true.


    Quote Originally Posted by Dennis link=1227707518/0#1 date=1227739356
    *I might in part agree with the first quote, though beginning with the proviso that the freezer would need to be a commercial deep freeze unit.
    Again, this statement appears to just be your own personal opinion. Based on what though? Your gut feeling? Personal experience? Blind taste test with a panel of experienced tasters?


    Quote Originally Posted by Dennis link=1227707518/0#1 date=1227739356
    Terms like, "near airtight...at least 2 months...not obviously inferior" are far from qualitative or quantative.
    Do you have a better source that shows the opposite? They went to a hell of a lot of trouble to make this test as scientific as they could, and I think they deserve proper credit for what they have done. If you’d like to carry out a more scientific test then I’d be interested to see the results.


    Quote Originally Posted by Dennis link=1227707518/0#1 date=1227739356
    Ill continue to suggest that coffee is stored in valved bags, in a dark, cool place like the pantry, and not in the fridge or freezer.
    Don’t misunderstand me. I’m NOT recommending that everyone to store their coffee this way. But IF someone NEEDS to keep coffee fresh for longer than 3 weeks or so, for whatever reason they may need to do so, this method does appear to help it to stay relatively fresh, even if it MAY not be quite as good as fresh roast. Some people may not be able to get fresh roast on a regular basis, so this may be an option for them.

    Personally I roast every week and store in valved bags so I always have fresh coffee on hand all the time. I rarely have coffee that’s more than 2 weeks old, so I have no need to find some method to preserve it for longer.

    But the point I really want to get across is that ‘accepted wisdom’ is not always true, and should be treated with scepticism unless there is some real evidence to support it, not just a personal opinion.


    regards,
    Bill

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    Re: Coffee myth - freezing coffee

    I tend to think that accepted wisdoms become that over time for valid reasons.

    For example, bush medicines that were "accepted wisdom" for aeons before white scientists "discovered" what made them work.
    IIRC asprin was one such medicine.

    I agree that some people may need to prolong the life of their coffee by freezing but the question I have is will they freeze, store and thaw it with the same level of care as those doing the scientific studies?

    If I did it Id put it in my chest freezer in the garage because it doesnt get opened as often as the one above the fridge in the kitchen.
    Also, the cold air doesnt fall out of it as it does from the other.

    Horses for courses.
    If you need to, try it and if it works for you, go for it.

    However Ill still recommend cool dark place in a valved bag as the optimum storage method for home.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by Dennis link=1227707518/0#1 date=1227739356
    The quotes youve provided are again, just a few peoples opinion, and Id suggest unscientific. *I might in part agree with the first quote, though beginning with the proviso that the freezer would need to be a commercial deep freeze unit.
    You have got to be kidding me. How much more scientific can you realistically get? The experiment was designed over at least a year and gave ample chance for Kens hypothesis to be disproved. It involved three different tasters - all of whom have a fair degree of experience with espresso at home and it resulted in enough data being collected to draw a pretty reliable conclusion. Additionally, two of the variables were clearly selected so as to reduce the impact of personal preference as much as possible. For crying out loud - how many coffee studies and experiments actually go to the trouble of collecting enough data to be able to use the chi square test to validate it?! If you cant attach credence to this, then, realistically, you probably arent going to believe anything that anyone writes.

    In any case, even if you persist in maintaining that Kens experiment isnt to be believed, you shoot yourself in the foot because you have established a ridiculously high standard of what it ought to take to convince readers of this thread and you adduce no evidence to support it. In doing so, your post seems to be totally in opposition to your apparent disapproval of accepted wisdom:

    I agree that a lot of truths are spawned from rumour that often begins with just one persons opinion.
    Regardless of what you personally may believe, you have to admit that this study was a helluva lot of work. The state of coffee knowledge will not advance unless people are prepared to do it and I know from discussion with Jim that all of this is a total PITA. It doesnt even seem that you did Ken et al the courtesy of reading what they wrote, as it contained something directed precisely at people who would make comments like yours:

    Now the ball is with the anti-freeze people, not to nit pick his results, but to announce something like "the difference between fresh and frozen is this, heres how you taste for it, heres how to set up a blind test." Any sort of "freezing is just bad—put some vague reason here—" is, after this test, simply BS. The test moves the debate to the realm of discussing narrow differences, precisely specified."
    The onus is clearly on you to adduce some evidence to a standard at least as high as Ken et. al. Or, at the very least, you could show how their study is wrong. The figures are all up there; doing the stats yourself would be a good start.

    Terms like, "near airtight...at least 2 months...not obviously inferior" are far from qualitative or quantative.
    Quantitative means (basically) something that can be measured. They have measured two months and they have adduced statistically significant evidence to show that the coffee was fine at that time. Near airtight I would argue is also quantitative, seeing as in this context it gives you an idea of how much air the seal on the container should allow in or out. I can only guess that your beef with these figures is that they arent expressed to a high degree of accuracy. The idea that you need to do that in order to be scientific or even credible is as wrong as saying that you have to wear a lab coat with a pocket protector to do anything scientifically.

    This sentence comes off as attacking the credibility of the result by continuing your misrepresentation of the study as unscientific. Perhaps what you meant to attack was usefulness of the results. If that is the case, the best that can be said of your argument is that you regard that conclusion as self-evident. It is not.

    The study purported to establish only what it actually covered and Ken et al were very conservative in setting out what they thought should be deduced from it. Further, the author(s) went so far as pointing out what it didnt establish. Flaws in the study arent immediately apparent to me.

    Raos conclusion is open to a lot more attack, but you will note that even he supports what he says with evidence. In what regard are the sources that he cites unscientific?

    If people are undecided as to whether to store coffee in the freezer, fridge, pantry, or even bury it in a treasure chest, I suggest that they perform their own little experiment with these methods, and come up with their own preference.
    Finally! Something that we can agree on!

    Cheers,

    Luca

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    Re: Coffee myth - freezing coffee

    Hahaha; Bill - beat me to the punch. Great minds.

    Cheers,

    Luca

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    Re: Coffee myth - freezing coffee

    Hi Bill,

    I understand what you are saying in regards to blanket statements that people take on as gospel without really doing any testing themselves. I do it all the time because often I trust the people that have experience in a certain area and the testing they have done. If there is some issue I really doubt, Id go away and test it. Most of the time I dont feel qualified to comment on things Ive had no experience on (machinery in particular), but will give my second crack with the disclaimer not to take me too seriously. I think its healthy in some discussions to bounce opinions around though to get to a common truth or whatever. Thats learning isnt it.

    In regards to freezing coffee I think there are some things to consider. One that I have recently been thinking of is in regards to FRESHNESS and CO2 release or degassing. I think they are two seperate (but do overlap) things. I think that we often talk of these as the same. The freshest the beans will ever be is immediately after roasting. As far as an optimum time where the CO2 gasses have sufficently been released and flavours are at their prime (or preference) varies obviously in regards to the bean type, roast profile, storage type, environment (freezer or room temp etc) etc. Finding that balance between actual freshness, optimal flavour/aroma and CO2 release is pretty subjective and Id rather let my palate do the talking on my own behalf for me :)

    I have heard some say that beans that are frozen(as in deep frozen) can release its CO2 while still retaining the flavours/aromas for longer periods. Ive never done any tests, nor do I plan to in any time soon, as the methods already laid out work for me.

    Refridgerating them in a semi-airtight container doesnt really appeal to me for the aforementioned reasons (fridge smell tainiting the coffee and moisture/condensation issues)

    Theres probably way more to be said here, but to stay true to the OP ill stop rambling :)

    Cheers,
    YeeZa

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    Senior Member flynnaus's Avatar
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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by YeeZa link=1227707518/0#10 date=1227746390
    the disclaimer not to take me too seriously
    So do we take this post seriously? :D

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by luca link=1227707518/0#8 date=1227745967
    For crying out loud - how many coffee studies and experiments actually go to the trouble of collecting enough data to be able to use the chi square test to validate it?! *
    ;D ;D ;D

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    Re: Coffee myth - freezing coffee

    Agreed, you can freeze coffee, but it is only when you store it, freeze it, defrost it and open it a certain way that the coffee will not be harmed/as harmed.

    Im guessing mot people here do not know those proper methods, therefore they will ruin their coffee if they try to freeze it. So I tend to be quite strong when recommending not to freeze it for this reason.

    In theory freezing does work, in reality it just not practicle

    I looked into this along time ago, it seemed way to difficult and hardly worth the effort.

    I believe Illys book covers this section quite well. For those who know the book, it too is quite in depth and helped written by several scientists. Therefor scientist will always disagree and it will be up to you in the end to try it out, and see what is the best method for you.

    I find most people who ask about freezing, talk about ground coffee, which does not freeze well under any circumstances, also they should be buying beans on a regular basis so should not have to worry about long term storage. With the amount of coffees out there, and the amount of new stuff coming through, why store beans?

    I really do not see any argument as to why you would want to store beans. This is more of a question to me, especially when a zip-lock, release valve bag in a pantry works perfectly fine.

    Coffee is still in its infancy, especially when you compare it to wine, and there are still several arguments that have been going on with wine for centuries.

    I love forums like this that brings in all the small amount of info on coffee thats out there together and we can argue, learn, develop, refine and help take coffee to that next level, even when we disagree, especially when we disagree

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    Re: Coffee myth - freezing coffee

    Luca & Dennis - give each other a cyber hug, please ;D

    Bill, youve evidently opened a can of worms that were squirming for a while on this forum in the past, but was categorically closed back then because uniform collective wisdom was "dont freeze".

    Perpetuated urban myth ... maybe.

    Without wanting to dip my toe too deeply into this verbal cauldron, can I just say that food exporters have for decades incorporated vacuum-packing as a means of retaining freshness at their relative destination.

    http://en.wikipedia.org/wiki/Vacuum_packing

    Blue-fin Tuna still fetches premium prices in Japan & Korea packed in this way.

    And on the domestic level - see the amount of snap-frozen veges on your local supermarket. Its vacuum-packed to retain freshness, & from what Ive experienced, better than fresh fruit & veg on offer on the shelf.

    Why is coffee, as a food, immune from the same process? :-?

    Thus, & henceforth, (thanks Luca for the reminder of legal lingo that I thought Id forgotten ;D), regardless of the scatterings of scientific opinions that we can all proffer & select from to justify our point of view, pontification is kinda futile.

    Do your own study, & relinquish the expert opinions from your head in the process.

    The results lie in your palate, not mine.

    Tony

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    Re: Coffee myth - freezing coffee

    I had a laugh while I agree with you totally GrindOnDemnd or GOD...

    There is also a huge argument as to the damage caused to coffee through vacuum pumping! hehe

    But thats for a different day me thinks, after all, Blue Mountain is always vacuumed pumped and it gets the top prices paid for it! (not a big fan of it myself)

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by MaxPower link=1227707518/0#15 date=1227751816
    There is also a huge argument as to the damage caused to coffee through vacuum pumping! hehe
    Yes, thats another can of worms that I have often thought of opening some discussion on. *;) Maybe Ill just leave that to another day.

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    Re: Coffee myth - freezing coffee

    Well said, Luca!

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    Senior Member flynnaus's Avatar
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    Re: Coffee myth - freezing coffee

    Tony

    Im not sure vegetables and fish are good examples for the freeze-vs-fresh debate. Tuna needs to be frozen because it has to travel huge distances back to its home markets. Likewise, fruit and vegetable arent as fresh as when they were first harvested and even when snapfrozen, they dont necessarily go straight from the farm into the processing plant. I would agree that snapfrozen would be better than off-the-shelf supermarket produce, depending on how long it was from harvest to shelf. The best vegies are usually those harvested fresh from the home garden.

    With coffee, we ultimately have a choice on how to store. While I am happy to accept there is probably little difference between deep frozen beans and fresh beans, I cant help wonder if anything is lost in the freeze and thaw process.

    I think Jims test should have been double-blind ie the person making the espresso did not know which beans were being used and that the tasters were independent ie just there for the tasting, not part of the test preparation. Im not questionning Jims objectivity but it would im prove the validity of what is necessarily a non-scientific study. I am overall willing to accept the claims of the study that the do-not-freeze myth is somewhat busted.

    For myself, I have thrown a 250g bag of beans in the freezer when I had an excess and, when thawed, seemed to be fine. But that was my assessment, with an untrained palate, and very much the novice - well, more of a novice than I am now *:-/.

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    Senior Member Dennis's Avatar
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    Re: Coffee myth - freezing coffee

    Good grief Luca, unlike yourself Im not going to dissect, analyze and scrutinise every word in a post, then respond with a novella. By now, you should have written enough papers to know that when a word is presented in inverted comma form like, unscientific, it is offered without definition. Id rather accept any posts in the context they are offered.

    I stand by what I said, in the context it was said. To infer that I am, "attacking" or trying to put words into my mouth like, "perhaps what you meant to attack..." is just silly.

    As for evidence, Ive tried frozen coffee and tried it when its not. I know which I prefer, and thats enough for me.

    Cheers!


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    Re: Coffee myth - freezing coffee

    Steve ...

    I totally agree that snap-frozen/vacuum packed produce (be it tuna, peas, or coffee) aint the ideal way of storing things.

    Fresh is best ... bloody hell, doesnt Woolies stake its name on that weathered cliche!

    What I am saying, is that in lieu of freshly ground coffee, food manufacturers have devised a means of retaining freshness in their produce - ie vacu-packing.

    Coffee is a food.

    Food has increased longevity via vacu-packing (ie air-tight freezing).

    Food manufacturers would discard the process if it was proven defunct.

    They havent, so therefore why is the process not applicable to coffee (be it whole roasted bean, or ground)?




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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by MaxPower link=1227707518/0#15 date=1227751816
    But thats for a different day me thinks, after all, Blue Mountain is always vacuumed pumped and it gets the top prices paid for it! (not a big fan of it myself)
    Is that pre-roast(green) or post-roast? Thats another can of worms in itself.

  23. #23
    Senior Member flynnaus's Avatar
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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by GrindOnDemand link=1227707518/20#20 date=1227754580
    What I am saying, is that in lieu of freshly ground coffee, food manufacturers have devised a means of retaining freshness in their produce - ie vacu-packing.

    Coffee is a food.

    Food has increased longevity via vacu-packing (ie air-tight freezing). Food manufacturers would discard the process if it was proven defunct.

    They havent, so therefore why is the process not applicable to coffee (be it whole roasted bean, or ground)?
    I guess its the type of freshness characteristics you are trying to preserve. In the case of coffee, we are really talking about preserving taste. With food, its retaining nutritional value and edibility. Certainly freezing is a much more effective way of extending shelf-life for food available in a superkarket. *I think flavour is compromised if you compare the taste of frozen vegies to freshly harvested.

    Common wisdom coming from forums like CS isnt just made up. Someone has tried an idea and it works for them, so if someone else follows that advice and it works for them , then the idea is reinforced. That doesnt mean that ideas that seem contrary to it are then wrong and an exception doesnt discount a rule. The freezing method that Jim mentions is probably more trouble than most are prepared to go to, assuming they have the Mason jars and deep freezer. I have regularly drank coffee that is older than 3 weeks since roast, let alone 10 days and, while it doesnt taste as good and doesnt produce the crema, Im not going to chuck it out because of some rule says so.

    Lets just accept that common wisdom is simply advice based on experience.


    Im happy not to have the last word on this debate but I think it is past its use-by date. Freeze your beans - or not!

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    Re: Coffee myth - freezing coffee


    While the collective opinion is "Do not freeze", I have never accepted this. Freezing is an option if you go about it carefully. For freshly roasted beans stored in zip-locked bags, first extract as much of the air from the sealed bag as possible, then let it degas for at least a day, to fill the bag with dry CO2 (which purges most of the remaining air at the same time) is the way to go before freezing. Then there should be no moisture to form frost on the beans.

    When you take the bag out of the freezer, first allow it to come to room temperature before opening, to prevent condensation forming on the cold beans.

    The caveats are that I have found that beans stored in a conventional fridge freezer do not get cold enough to prevent aging effects. The fact that you can still smell the aroma of the beans through the one-way valve is an indication that the oils havent been immobilised within the bean. I suspect youd need to go a lot colder to accomplish this, maybe with a chest freezer.

    Ive found a standard freezer will prolong the aging process allowing you to keep beans for maybe a month without losing too much flavour.

    Cheers,

    Mark.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by Sparky link=1227707518/20#23 date=1227757562
    While the collective opinion is "Do not freeze", I have never accepted this. Freezing is an option if you go about it carefully. For freshly roasted beans stored in zip-locked bags, first extract as much of the air from the sealed bag as possible, then let it degas for at least a day, to fill the bag with dry CO2 (which purges most of the remaining air at the same time) is the way to go before freezing. Then there should be no moisture to form frost on the beans.

    When you take the bag out of the freezer, first allow it to come to room temperature before opening, to prevent condensation forming on the cold beans.

    The caveats are that I have found that beans stored in a conventional fridge freezer do not get cold enough to prevent aging effects. The fact that you can still smell the aroma of the beans through the one-way valve is an indication that the oils havent been immobilised within the bean. I suspect youd need to go a lot colder to accomplish this, maybe with a chest freezer.

    Ive found a standard freezer will prolong the aging process allowing you to keep beans for maybe a month without losing too much flavour.

    Cheers,

    Mark.
    As a man who splits atoms for a living, are they your rigorous scientific findings, or personal opinions Mark?*;D

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    Re: Coffee myth - freezing coffee

    The outcome of the "test" run by Ken and friends seems reasonable enough but in my personal experience of running true scientific tests over the years on a variety of subjects, the mere fact that a "chi-square test" can be used to validate or otherwise the end results, does not mean necessarily, that the manner in which the test was run can reliably produce repeatable results in all circumstances. I would call it a pseudo-scientific test.

    That being said, if coffee snobs take all the appropriate precautions for both freezing and thawing, some of which Mark has touched on above, then there is no reason why it shouldnt be done because circumstances have dictated it as the best available option.

    Overall though, I wouldnt recommend that freezing freshly roasted coffee should be widely adopted just for the sake of doing it. Much better, IMHO, to match ones roasting output to ones consumption rate and drink excellent coffee all the time. Preparing coffee from improperly frozen/thawed beans would have the same appeal for me as using 6 month old stale beans. I guess it becomes more of an issue where, due to specific circumstances (like Minnesota Winters e.g.), some people might not be able to roast all year round and need to be able to store coffee for extended periods.... Fair enough.

    Whos up for some experimentation with Vacuum and Non-Vacuum stored beans.... Rigorous scientific method ONLY please :P

    Mal.

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    Re: Coffee myth - freezing coffee

    and to think nobody so far has mentioned storing beans in the FRIDGE :o

    ;D

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    Re: Coffee myth - freezing coffee

    Coincidentally I this week gave some advice to a friend whos asking what machinary to get:
    "Roasted coffee beans are very hydroscopic, or whatever the word is for attracting moisture. Moisture makes coffee beans go stale. So does oxygen to a lesser degree. Keep them in a cool, dark, sealed place. Avoid the fridge unless you like fridgy, stale flavour. Freezing sealed bags is acceptable if you have too much coffee in stock, so long as you let it warm up before breaking the seal to avoid condensation on the beans. Do not return to the freezer once open."

    Which sums up my view. I found that it made 7 week beans taste like 3 week beans. My studies werent sooper scientific mind.

    Though at the moment the roasting is trying to keep up with consumption, so Ive not felt the need to freeze for many months now.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by BrighterSide link=1227707518/20#26 date=1227777444
    and to think nobody so far has mentioned storing beans in the FRIDGE :o ;D
    Troll! Troll! ;D

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    Mal Dimal's Avatar
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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by BrighterSide link=1227707518/20#26 date=1227777444
    and to think nobody so far has mentioned storing beans in the FRIDGE :o

    ;D
    Back to the crypt with you, ye of the black soul...... [smiley=evil.gif]

    Mal.

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    Re: Coffee myth - freezing coffee

    YEZZA, they vacuum pack their GREEN BEANS. Seriously.

    Quite the worm farm we are all starting! hehe

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    Re: Coffee myth - freezing coffee

    Interesting post

    However the beans in my household only last 2 to 3 weeks

    That[ch8217]s why I say fresh is best

    But if you need to freeze beans for what ever reason/s?
    I am sure there will be some legitimate ones for freezing beans.

    Then who am I to stop you
    As long as you like the coffee that[ch8217]s all that matters.

    KK

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by MaxPower link=1227707518/20#30 date=1227795349
    YEEZA, they vacuum pack their GREEN BEANS. Seriously.
    Im totally cool with greens being Vac packed. Ive got a 12.5kg slabs of Brazil Daterra thats as hard as a brick Vac sealed. Daterra farms seem to be doing some good things.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by Mal link=1227707518/20#25 date=1227772338
    The outcome of the "test" run by Ken and friends seems reasonable enough but in my personal experience of running true scientific tests over the years on a variety of subjects, the mere fact that a "chi-square test" can be used to validate or otherwise the end results, does not mean necessarily, that the manner in which the test was run can reliably produce repeatable results in all circumstances. I would call it a pseudo-scientific test.
    Oh, now that is too much. What the dickens does "pseudo-scientific" mean (in this context), and since when are tests based on the chi-square distribution "pseudo-scientific", in any sense of this misused phrase?

    Now if you mean that they are too frequenty quoted without reference to the underlying assumptions and/or limitations by "pseudo-scientists", that I will grant you.

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    Re: Coffee myth - freezing coffee

    I have to admit that I find some of these posts to be a bit of a head scratcher.

    Dennis, your response it totally absurd, but I really dont see anything to be gained in continuing our exchange. *Suffice to say to point out what I hope is obvious; my comments on this thread are directed to your post and not to you.

    Mal, I think that its a fair inference that your post is directed at mine and I will offer a brief response on that footing. *I dont attach any great significance to the term scientific in this context. *What I do attach significance to is the thoroughness of the experiment. *Whether or not it is scientific, I think that the results are thorough enough that people who are undecided ought to consider them convincing enough to at least be worth trying following the freezing procedure in the article - and ignoring any advice to the contrary that is based on less thorough experimentation. *Reading this thread, one would almost think that people consider Ken et als experiment to be less convincing because they are more thorough than what is usually advanced on the internet!

    Cheers,

    Luca

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    Re: Coffee myth - freezing coffee

    What Luca said.


    BTW: The experiment was also designed and analyzed by Jim Schulman, who has significant statistical expertise. Mind you, determining true randomness on such a limited data set is not possible. However the data passed the criterea for randomness given the limited data set. At that level, Id be prepared to put my hands up and say, "Ok, you cant taste the difference."

    The bottom line is that it cant hurt to try it and find out for yourself.





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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by luca link=1227707518/20#34 date=1228046862
    Reading this thread, one would almost think that people consider Ken et als experiment to be less convincing because they are more thorough than what is usually advanced on the internet!

    Cheers,

    Luca
    Absolutely not Luca....

    I think their experiment was very thoroughly executed and the results quite meaningful. I just think you need to be careful when assigning status to any kind of experiment. As far as putting people like Jim Schulman up on a plateaux that seems to intimate that he can do no wrong and everything he says must be believed, is also erroneous. Id rather that references be supplied so that people who may have an interest in such experiments, can read for themselves the credentialed work of the various contributors.

    I know from reading use.net alt.coffee over the years that people like Jim Schulman seem to be exalted as Gods of the coffee fraternity. None of that washes with me, never has... But thats just me.

    Cheers All,
    Mal.

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    Re: Coffee myth - freezing coffee



    I think youve clarified your position quite well, Mal, and I respect it.

    I had no intention of praising a coffee guru, but wanted to put the statistical expertise into perspective.

    However, I also agree with Luca, that these people have gone to great lengths to test a coffee related urban myth and found it wanting. The only scientific way to verify their findings is to conduct a similar test under conditions that adhere to the same level of control that they outline. So it comes down to one methodical study vs perpetuated dogma. Take your pick.

    Cheers,

    Mark.

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    Re: Coffee myth - freezing coffee

    Hell no Mark,

    The ongoing and very annoying perpetuation of misinformation is a pet hate of mine... in that context Ill take (properly documented) methodical study every time...

    Mal.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by Mal link=1227707518/20#38 date=1228124715
    Hell no Mark,

    The ongoing and very annoying perpetuation of misinformation is a pet hate of mine... in that context Ill take (properly documented) methodical study every time...

    Mal.

    But even that can be flawed..... when the goal is defined and then proof of that goal is sought (by scientific means or otherwise)....

    Many years ago I was working at Adelaide University in the Physics department where a Professor and a student were undertaking a PhD project to prove the existence of a particle which travels faster than light in the Cosmic ray lab....

    This involved a device which captured and stored a digital waveform so that you could look before a given event (the trigger) which in this case was the arrival of the light from the event in the universe...... and they found.... and documented.... the existence of a particle which arrived before the light - a result which was published throughout the world....

    When recalibrating the equipment (a Biomation as far as I can remember) I discovered cross talk between the trigger and the stored wave... which displayed as an event before the trigger - each and every time..... (and was exactly as their published work)....

    When this was shown to them, they didnt want to know..... as that would mean their scientific method was flawed and the report a hoax....

    So I even take scientifically made measurements with a grain of salt where the answer is known (and the process is all about proving the desired answer)..... it brings the process into disrepute and, IMHO, one then needs to question the whole process and it needs to be verified independently (ideally by someone who believes the reverse to be true).

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    Re: Coffee myth - freezing coffee

    What was that thing that annoying nerdy kid in primary school used to say after asking me a question and then proceeding to follow it up with, "Prove it." Obviously walking away frustrated, he comments, "The only thing you can prove, is that you cant prove anything.".... to which I questioned- "Prove it."

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    Re: Coffee myth - freezing coffee

    Ive always been a sceptic, requiring proof for anything and everything being claimed by somebody as fact. Thats why, if you at least have access to decent documentation, you can formulate in your own mind the basis of the fact(s) being claimed and then subject them to what ever rigorous sequence of tests that best suits the subject.

    Nothing wrong with being a sceptic in my view....

    Mal.

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by Mal link=1227707518/40#41 date=1228137781
    Nothing wrong with being a sceptic in my view.....
    I have my doubts about scepticism ;)

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    Re: Coffee myth - freezing coffee

    Quote Originally Posted by JavaB link=1227707518/20#39 date=1228126785
    Quote Originally Posted by Mal link=1227707518/20#38 date=1228124715
    Hell no Mark,

    The ongoing and very annoying perpetuation of misinformation is a pet hate of mine... in that context Ill take (properly documented) methodical study every time...

    Mal.

    But even that can be flawed..... when the goal is defined and then proof of that goal is sought (by scientific means or otherwise)....

    Many years ago I was working at Adelaide University in the Physics department where a Professor and a student were undertaking a PhD project to prove the existence of a particle which travels faster than light in the Cosmic ray lab....

    This involved a device which captured and stored a digital waveform so that you could look before a given event (the trigger) which in this case was the arrival of the light from the event in the universe...... and they found.... and documented.... the existence of a particle which arrived before the light - a result which was published throughout the world....

    When recalibrating the equipment (a Biomation as far as I can remember) I discovered cross talk between the trigger and the stored wave... which displayed as an event before the trigger - each and every time..... (and was exactly as their published work)....

    When this was shown to them, they didnt want to know..... as that would mean their scientific method was flawed and the report a hoax....

    So I even take scientifically made measurements with a grain of salt where the answer is known (and the process is all about proving the desired answer)..... it brings the process into disrepute and, IMHO, one then needs to question the whole process and it needs to be verified independently (ideally by someone who believes the reverse to be true).
    I think this example is a bit of a straw man. This is just an example of a couple of people who got too excited about the prospect of what they may have found and so failed to conduct the proper cross checks. You should always run a null experiment to ensure everything behaves as it should.


    Heres what I get out of this thread. We have two examples given by the OP of why freezing roasted beans can be used successfully to increase the longevity of a roast.

    The first example explained the phenomenon in terms of chemical and physical characteristics of the process. The second example was of a reasonably rigorous procedure of blind tasting to look for a qualifiable difference between fresh and frozen, using multiple tasters. (A very cold chest freezer was used to store the beans)

    I have personally tried freezing beans in a standard fridge freezer and found no significant advantage, probably due to the freezer not being cold enough for the job. However, the beans were not degraded according to my palate, either.

    Given that coffee beans contain very little moisture and no free moisture within the bean itself, freezing is unlikely to damage the bean due to microscopic phase changes. Oxidative chemistry requires thermal energy to proceed, so by removing some of that energy, you are slowing down the process. Fats and oils increase in viscosity with reducing temperature, so you can slow migration of these substances within the bean by lowering the temperature. Basically, freezing does just that; it slows of freezes the basic process that result in aging. This is pretty sound science, so why should coffee be any different?

    OTOH, we have some proponents of the "Do not freeze" fraternity who have offered their advice without further qualification.

    I think the fair response to anyone asking this question in the future would be: Yes you can freeze beans if you are careful, but most CSers prefer not to.

    Cheers,

    Mark.


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    Re: Coffee myth - freezing coffee

    Scientific experiments need to be done and reviewed properly, admittedly. But I get a bit cheesed off when people doubt science because they dont really trust the scientist, and then weigh the evidence equally with say, something someone said, or urban myth, or the presenter off Today Tonight, or some crackpot with a web site.

    Weve all got coffee machines and probably all got freezers. A rare chance to test a theory out yourself. And properly designed you could get an experiment done across CS, which would cover all sorts of bean types and machines.



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