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Thread: One Way Valve Bags Re-Used

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    One Way Valve Bags Re-Used

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    G"Day CS

    For you lot in the know, can the bags on offer in bean bay be re-used or do they need to be thrown out after one use? For budgetry reasons, it would be good if I could get a couple of uses from them!

    Other wise, would a couple of holes in a zip-lock bag tightly rolled up have the same effect? ::)

    Thanks
    Andrew

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    Re: One Way Valve Bags Re-Used

    I use mine a few times.
    You can wash them out and dry thoroughly.
    I think Mal wipes his out with some kind of alcohol (no not scotch!).
    I dont think a pinhole in a ziplock back is quite as good.
    Anyway, after theyve degassed, a ziplock without holes is probably fine.

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    Senior Member robusto's Avatar
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    Re: One Way Valve Bags Re-Used

    I use the supermarket ziplocks with a pin prick and everything works fine. After several uses they can be disposed of. But use your nose and eyes to see if they are rancid with stale oils. If they appear ok, a wipe with a tissue will extend their life.

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    Re: One Way Valve Bags Re-Used


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    Re: One Way Valve Bags Re-Used

    Very interesting Mal. Ive always found the bags develop a very burnt ashy smell (which I presume is the stale smell) after theyve been used once, and when I tried to reuse them (say, for dividing a 500g bag into 2x250), the new beans would take on that burnt ashy smell and destroy whatever characteristics they once had; so since then Ive reluctantly tossed them out.

    I might just have to raid the spray can of isopropyl PCB cleaner I have tucked away for that rework job and put it to a better use! Wink Will be most interested to see how well this works!

    Greg

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    Re: One Way Valve Bags Re-Used

    Where do you purchase new bags from?
    Dave

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    Re: One Way Valve Bags Re-Used

    You can get them on Bean Bay.
    If you are wanting a lot though, I would check out one of the sponsors - Coffeeparts.

    Rgds
    Ben

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    Re: One Way Valve Bags Re-Used

    Re reusing valved coffee bags,

    I have also noticed that ashy, rancid, stale odour that Greg mentions....... so my solution is not the use of isopropyl alcohol but to use a little machine cleaner (Cafetto or similar) in hot water, rinse and pat dry the bag then leave opened in a warm place, ie on top of the espresso machine for a while to completely dry, problem solved and can reuse until the bag fails mechanically.

    Cheers Gazz

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    Senior Member Lizzie's Avatar
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    Re: One Way Valve Bags Re-Used

    i clean 3 or 4 bags in one go: about 1/3 cup of metho in the bag, brush well with (special for the purpose) dish-brush, so you can get in all the nooks and crannies, tip out the metho ( into the next bag...), rinse out with very hot water, dry pegged up on the washing line.
    8 month old bags still smell like new... or rather: no smell at all ;)

    L

    PS very VERY hot water is not such a good idea... :( i ended up with double-sided-opening-one-way-valve bags ;D ;D

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    Re: One Way Valve Bags Re-Used

    Dont know about the use of Isopropyl Alcohol, I thought this stuff was rather poisonous. Ethyl alcohol is really easy to get from most pharmacies and does not represent any kind of danger (so long as you just use it for cleaning and NOT imbibing ;) ::)).

    I just use a similar method to that described by Lizzi except that I forego the rinsing out with hot water. Prefer to wipe dry with a paper towel and then leave open in a warm possie to thoroughly dry out. Never end up with any untoward odours of any kind and since no water is used, the bags end up being perfectly dry.

    Cheers,
    Mal.

    Excerpt from Wikipedia Article....

    Medicine/Toxicology:

    Isopropyl alcohol is about twice as toxic as ethanol. Isopropyl alcohol does not cause an anion gap acidosis (like ethanol or methanol). It produces an elevated osmolal gap, but generally no abnormal anion gap (though this may be seen as a result of hypotension and lactic acidosis). Overdoses may cause a fruity odor on the breath as a result of its metabolism to give acetone (which is not further metabolised)[5]. While large quantities of isopropanol can be fatal if left untreated, it is not nearly as toxic as methanol or ethylene glycol.

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    Re: One Way Valve Bags Re-Used

    Interesting reading this because I have been using some one way bags for over 12 months without any issues of rancid odours, etc. I wipe them out with alcohol wipes after each use and they are fine for re-use.

    I keep waiting for either the zips or the valves to go but so far have not had one fail on me.

    Mal, we are obviously in a different regime in Melbourne, no pharmacy, and I have tried numerous, will sell me ethyl alcohol. All I have been able to get is the wipes. They work fine though.

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    Re: One Way Valve Bags Re-Used

    OK maybe I wont try any "cafe au poisson" in my home kitchen! :) Thanks Dr Mal!

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    Re: One Way Valve Bags Re-Used

    Medicine/Toxicology:

    Isopropyl alcohol is about twice as toxic as ethanol. Isopropyl alcohol does not cause an anion gap acidosis (like ethanol or methanol). It produces an elevated osmolal gap, but generally no abnormal anion gap (though this may be seen as a result of hypotension and lactic acidosis). Overdoses may cause a fruity odor on the breath as a result of its metabolism to give acetone (which is not further metabolised)[5]. While large quantities of isopropanol can be fatal if left untreated, it is not nearly as toxic as methanol or ethylene glycol.

    Which Means that something (IPA in this case) exerts an Osmotic gradient between your blood stream and cells = "Osmolar gap" this in turn causes a fluid shift and will dehydrate your cells. This is significant for your brain mainly and can cause coma and death. HOWEVER I see this in the ICU only occaisonally when people have drunk an osmotically active solution , such as Anti Freeze ( ethylene glycol). More common in the US with Alcoholics.

    You would need to ingest a reasonable amount

    If you wash out your bags properly I dont imagine the exposure would be huge . How much do bags cost?

    Regards
    Dr dave

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    Re: One Way Valve Bags Re-Used

    Quote Originally Posted by Greg Pullman link=1198287865/0#11 date=1198715931
    OK maybe I wont try any "cafe au poisson" in my home kitchen! :) Thanks Dr Mal!
    Definitely not a Doctor Greg, just careful..... Dr. Dave is the genuine article 8-)

    Mal.

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    Re: One Way Valve Bags Re-Used

    Why even bother with alcohol? A good dishwashing detergent should remove any old oils from the bags.

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    Senior Member Lizzie's Avatar
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    Re: One Way Valve Bags Re-Used

    most dishwashing detergents are perfumed... and that smell is hard to get out of the bags ;)

    L

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    Re: One Way Valve Bags Re-Used

    I did try detergent once and I was left with the concept of my beans adopting a mixture of rancidity and pine-o-kleen!

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    Re: One Way Valve Bags Re-Used

    my beans adopting a mixture of rancidity and pine-o-kleen
    pine-o-bean..... ;D ;D

    L

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    Re: One Way Valve Bags Re-Used

    "...full-bodied with a slight tobacco taste, but then blends into a smooth alpine finish"

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    Re: One Way Valve Bags Re-Used

    Ive been going down the local coffee, tea, spices etc shop and they sell me 5 zip-lock valved bags for $1 which I consider a bargain, they last me quite a few roasts so I hope they continue to supply me.

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    Re: One Way Valve Bags Re-Used

    greenman, please enlighten me on this bargain, PM me if you want to

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    Re: One Way Valve Bags Re-Used

    I ran across a nifty idea on another web site. It involves using one of those click lock type plastic containers which have a rubber seal embedded around the edge of the lid. You need to drill a small hole in the lid, just a little bigger than the hole in the bags one way valve. You then cut out the one way valve from the plastic bag leaving a border of plastic around the valve, then sticky tape it under the lid (lining up the holes) running the tape around the border of plastic. This makes an air tight seal. I use the size which neatly holds about 80g of beans. This lasts me for nearly a week. Seems to work well. The big plus, is that it makes washing the container out really easy. If the one way valve goes belly up, then its easy to replace. The only down side is that as you use the beans there is an ever growing air space above the beans, where as the bag allows you to get rid of most of this.

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    Re: One Way Valve Bags Re-Used

    After reding this thread and looking on coffeeparts site Im buying a vacuum seal container. Has a pump to remove the air. Seems a reasonable compromise. Able to be cleaned in dishwasher and not wasting bags
    Dave

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    Re: One Way Valve Bags Re-Used

    Before you spend your dollars on that... the benefits of a bag is that you can expel all the oxygen without creating a vacuum. Just recently JavaB pointed out the problem with these; you really need a bag with which you can get rid of all the oxygen without creating a vacuum to suck the volatiles out of the beans. Even a sealed jar holds more and more oxygen as the bean levels get down, whereas a bag with all the air squeezed out is ideal.

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    Senior Member greenman's Avatar
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    Re: One Way Valve Bags Re-Used

    I have one of these containers Dave and when I posted about using it several people canned them saying it sucks out all of the aroma etc.....until then I thought it was doing a good job!!
    Ive gone back to zip-locks but still have the container there in case opinion changes on this.

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    Re: One Way Valve Bags Re-Used

    greenman, with all respect let your tastebuds be the test. It is slightly concerning that you were happy with its results until other people canned the method, even though the results were as good as they were before then. There are plenty of learned opinions here on CS and Ive learnt a lot from reading others thoughts; but at the end of the day, youre drinking the stuff so if youre happy with it then it doesnt matter how that result comes about, even if its by some non-preferred method. Opinions and knowledge help but there always has to be room for individual preferences.

    Id be very interested to read how you find the difference between bags and the vac canister in terms of how long the beans last; is there a noticeable difference in flavour over time?

    Greg

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    Senior Member greenman's Avatar
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    Re: One Way Valve Bags Re-Used

    My beans dont usually last long enough to go stale Greg, the canister holds about 250g and the way my crew like coffee they only last a few days!!! I keep the remainder of the roast in zip-locks.

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    Re: One Way Valve Bags Re-Used

    Ok guys, heres what Ive found since changing over to the bags from the Vacuum cannisters:
    I cant say Ive noticed any difference in the cup but, I have noticed that the beans seem to keep their aroma in the bags. The aroma disappears pretty quickly in the cannisters. Im convinced now that this is the way to go so Ive stocked up on bags from Coffee Parts.

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    Re: One Way Valve Bags Re-Used

    Ive nicked some one-way valves off of a "company to remain nameless" coffee tin. The one that mounts on your grinder.

    Just got to get some good click clack containers.

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    Re: One Way Valve Bags Re-Used

    nanu,

    The problem with containers.... with or without the one way valve.... is you have lots of trapped air in them.... which will oxidise the coffee oils....

    At the professional coffee machine training session, the instructor went to great pains to explain that after you take some coffee out (or empty the hopper contents back in the bag at the end of the day) you seal the bag and then roll it up tightly from the bottom towards the one way - expelling as much air as possible along the way.... and you will get most of it out.

    With a container the only way you can remove as much air as possible is to ensure it is absolutely full of beans at all times.... which is possible - but not very practical!! And even then, squeezing the bag whilst rolling will probably remove more.

    I dont know why people try to find alternatives to the bags.... they are not that expensive and ALL quality roasters use them.....

    It is only the cheap and nasty beans that come in vacuum sealed bags - a few come in tins.... with use by dates a year from roasting :P!! Arent our precious beans worth proper storage? We make sure every part of the process is as good as it can be, then try to save a few cents by not using the best storage medium.....

    Seems strange to me ::) ::) ::)

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    Sleep is overrated Thundergod's Avatar
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    Re: One Way Valve Bags Re-Used

    I agree JavaB.
    The cost of bags is minimal.
    I do reuse a few for personal use.
    When roasting for others, I dont give a thought to the cost of a new bag.

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    Re: One Way Valve Bags Re-Used

    Quote Originally Posted by Thundergod link=1198287865/30#30 date=1198824052
    I agree JavaB.
    The cost of bags is minimal.
    I do reuse a few for personal use.
    When roasting for others, I dont give a thought to the cost of a new bag.
    I guess thats all relative TG. When ones sole source of income is a govt. pension one tends to reuse items as much as possible or find alternative cost-saving uses. Naturally, always provide beans for friends and relos in 1-Way Valve bags of course but have a standing request that all bags are looked after and returned when they next visit. After all, theres a good chance of a top-up for them ;). Horses for courses,

    Mal.

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    Re: One Way Valve Bags Re-Used

    Point taken.

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    Re: One Way Valve Bags Re-Used

    This has been quite an interesting thread.

    I impulse seal my bags when I put the beans in them, so they are not really suitable for re-use.

    Then again, I did go out and buy a box of 500 bags some time ago when I started roasting for others (long story), so until I can see the bottom of the box, I havent really been looking into re-using them. ;-)

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    Re: One Way Valve Bags Re-Used

    Fair nuff fb ;D

    Mal.

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    Re: One Way Valve Bags Re-Used

    Quote Originally Posted by fatboy link=1198287865/30#33 date=1198827465

    I impulse seal my bags when I put the beans in them, so they are not really suitable for re-use.
    I have an impulse sealer as well fb.
    I dont see how that prevents reuse.

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    Re: One Way Valve Bags Re-Used

    Because I cannot be bothered positioning the seal up high and using scissors to open the bag when it is ready to use and then progressively moving the seal down a bit next time etc..

    I just rip em open when I need them and toss them when empty.

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    Re: One Way Valve Bags Re-Used

    I only seal some of those I give to others.
    Especially if I know they are a gift and likely to travel a bit.

    But for immediate use (or close enough) isnt the ziplock enough?
    Especially if you use the beans within say a week?

    Whats the point of you sealing them until ready for consumption?

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    Re: One Way Valve Bags Re-Used

    Surely the point of heat-sealing the bags is to prevent the opening of the bags during travel; or to stop nosey shoppers from opening them while on the shelves. If used at home for home-roasted coffee, I cant see the point of sealing them. The ziplock would be sufficient, wouldnt it?

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    Re: One Way Valve Bags Re-Used

    Well, part of the reason I seal them is that I do not believe that the zip lock is sufficient. For these particular bags anyway.

    When I do not seal them, the bags dont expand as much as when I do.

    So, I have been sealing them as a matter of course.

    Perhaps once I get through the last 300-400 of these, Ill get a different style of bag and see how they go with just the zip lock.

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    Re: One Way Valve Bags Re-Used

    Id be interested to know if anyone has done a real world test on beans in containers compared to beans in bags. I know the argument about the amount of oxygen coming into contact with the beans in both methods as they are in storage, but does it really make that much difference in the short term or is it just a case of assumptions being made?

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    Sleep is overrated Thundergod's Avatar
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    Re: One Way Valve Bags Re-Used

    IIRC jacs it has been done.
    You could do a search of the site and see if you can find the threads.

    Even without finding the thread could you not believe that the collective knowledge of the group has worked out the best method by now?

    Any assumption made is based on the fact that oxygen is the enemy of coffee.
    A jar lets more oxygen stay in contact with the beans than a bag with the gas squeezed out.
    Therefore I will stave off the degredation of my coffee as much as possible by using a bag.
    Even if I dont have a palate discerning enough to tell the difference, someone else I serve my coffee to may have.
    And Im snobby enough to care.

    Everyone here is fussy about their coffee. and arent "sheep".
    They question things and try to prove/disprove theories.

    Im an auditor; I question things all the time.
    I used to have an email tag at work that read "In God we trust; everyone else we check".

    If the majority say bags are better, then they are.


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    Re: One Way Valve Bags Re-Used

    Quote Originally Posted by fatboy link=1198287865/30#39 date=1198882799
    Perhaps once I get through the last 300-400 of these, Ill get a different style of bag and see how they go with just the zip lock.
    Which style of bag are you using now fb?

    Mal.

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    Re: One Way Valve Bags Re-Used

    They are clear on one side and gold on the other - 250g. Some of them were offered up for sale here quite a while back.

    In 2 years or so (when I run out), I will try the solid colour ones like coffeeparts and Andy sell. I might even get curious before then 8-)

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    Re: One Way Valve Bags Re-Used

    Ive got similar ones from coffeeparts.
    Clear one side, black the other.
    Ive thought about getting all black next time but I like the look of the beans.

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    Re: One Way Valve Bags Re-Used

    Quote Originally Posted by Thundergod link=1198287865/30#44 date=1198912522
    Ive got similar ones from coffeeparts.
    Clear one side, black the other.
    Ive thought about getting all black next time but I like the look of the beans.
    I just bought the same ones. Although all black is probably best, Im sure theyll be fine stored in a cupboard.
    I roast 400g of green beans which gives me approx 325g when roasted. The 500g bag fills up nicely with very little air/space left behind.

    Evan.

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    Re: One Way Valve Bags Re-Used

    I roast 300g which gives me 250 roasted and they fit in the 250g bags.

    I would say from your description Evan that you arent expanding the gusset.
    I have to, to make mine fit, but then the bag sits upright too.

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    Re: One Way Valve Bags Re-Used

    I found this bottle of specially methylated spirit and contains 98ml/100mL Etthanol and 2g/100g Methanol. It seems to be old as the EXP is 4/98. Is it still safe to use to wipe out the bags?

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    Re: One Way Valve Bags Re-Used


    Wow, I didnt know that stuff had an expiry!

    I can only assume its more to do with the container getting old and brittle and not the contents going off. Alcohols dont really go off, they do attract water and become diluted but I would doubt you would have a problem using it.

    Just make sure it doesnt smell like the plastic bottle that its stored in.
    (not a very good aroma trait for coffee)

    ;)

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    Re: One Way Valve Bags Re-Used

    If you have problems buying pharmaceutical ethyl you can always buy a bottle of vodka and use that. :)


    Java "And it comes in glass!" phile



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