Jump to content
Zeta

Long-term storage of nuts: moisture control

Recommended Posts

Just bought 10 kg walnuts. After doing some research, I realize it's likely OK to freeze walnuts (though I still would like experimental confirmation that a phenomenon similar to the one Michael has noted takes place in olive oil -- damage via phase changes -- wouldn't occur [1]).

 

But it seems particularly important that nuts, walnuts and all nuts, be kept as dry as possible, at whatever temperature they're kept.

 

My plan: buy a bunch of silica gel cat litter, and toss in 50 or so g per kg of nuts in an air-tight container, then freeze. Cheap and effective!

 

My question: Under the assumption that I always thoroughly rinse, and then soak, my nuts, can anyone think of a reason why this wouldn't be a good idea? Maybe a small amount of tiny grains would work their way into the nuts? But if it's pure silicon dioxide, shouldn't be a prob., right? Big "if", perhaps. If money weren't an object at all I would buy a bunch of desiccant packets, but why spend such a huge amount of money if cat litter would do the job perfectly!

 

Thanks,

Zeta

 

P.S. I know I owe folks responses in many other threads. Suffering a bad combo of work overload plus sleep crisis. Not really human right now. [2]

 

[1] 

http://arc.crsociety.org/read.php?2,209540,209583#msg-209583 (but archives still down...),

also:

http://pubs.acs.org/doi/abs/10.1021/jf051808b (cited by Michael in the above).

"Phase change, wha? Walnuts are solid!" Right, thus "similar" phenomenon, not "same". But there are a bunch of oils in walnuts. They aren't solid. But, obviously, being partially "locked" in a matrix would limit problems with crystallization and such.

 

[2] Would be eternally grateful if someone could provide suggestions (off-list) about how I could get either suvorexant or zaleplon (Sonata) in Europe. (FAQ: "But have you tried X for your sleep problems?" A: Yes, where X = everything imaginable aside from zaleplon or suvorexant.) I would of course never put this forum or community at risk by requesting advice on using the darknet or whatever... since that would be illegal, though that may be my only option. Well: Oil is so cheap ticket prices to the US are down to $400. Maybe there's a doctor in New York or Boston reading this who'd see me sort of cheaply and write me a prescription for both.

Edited by Zeta

Share this post


Link to post
Share on other sites

Zeta,

 

It seems like if you soak and rinse your walnuts there isn't any chance your nuts will have silica residue on them. I just wouldn't let my cat use the kitty litter first!  :)xyz

 

Alternative #1 - Silica Gel Pad Dessicants - $10 + free shipping from Amazon for a pack of 25. That way no worry about residue since the silica is sealed inside the pad.

Alternative #2 - Vacuum Sealing - I'm still not sure why you're reluctant to use the vacuum sealing solution. It prevents both ice buildup and oxidation.

 

Here is the same vacuum sealed bag of walnuts from Hagg Farm I pictured in this post from October. They have not changed, and when I open them they will be (or at least appear, for all intents and purposes) as fresh as the day I sealed and froze them.

 

--Dean

 

2ao7jnZ.png

Share this post


Link to post
Share on other sites

Just bought 10 kg walnuts. After doing some research, I realize it's likely OK to freeze walnuts (though I still would like experimental confirmation that a phenomenon similar to the one Michael has noted takes place in olive oil -- damage via phase changes -- wouldn't occur [1]).

To be clear, as I have discussed and generally documented each time I've posted/group-messaged on this, even WITH the freeze-thaw cycle problem, you're STILL better off on net freezing EVOO for long-term storage. The main question is what the cutoff point for "long-term storage" is, when the long-term benefits of freezing outweigh the acute detriment of freezing and thawing. It seems clear that this is < 3 mo.

 

And, as you say, it seems reasonable to think that problems with crystallization would be limited in nuts because the lipids are still embedded in membranes and/or fat vacuoles.

 

IAC, experimental data trumps theory and extrapolation! You evidently missed my previous posting, in a thread on nuts started by Brian Delaney, of

 

a review by the UC Davis agricultural extension on "Estimates of Shelf-life of Raw Nuts Held at Different Temperatures." It confirms that even by basic quality parameters (ie, not maniacal health-nut worries about the very last molecule of peroxidized fat or acrylamide), the shelf-life of raw nuts at "cool, dark place" temperature (20°C/(68°F) is never more than 6 months, and that progressively lowering the temperature to "autumn morning" (10°C/50°F), freezing (0°C/32°F), and slightly-less-than-home-freezer (-10°C/-14°F) temperatures each extends shelf life by months. Going the opposite way (from -10 to 20ºC), the shelf-life for macs falls from 24 mo to 12, 12, and 5 mo with rising temp, and is only 0.75 mo at 30ºC/86ºF.

 

But it seems particularly important that nuts, walnuts and all nuts, be kept as dry as possible, at whatever temperature they're kept.

 

My plan: buy a bunch of silica gel cat litter, and toss in 50 or so g per kg of nuts in an air-tight container, then freeze. Cheap and effective!

 

My question: Under the assumption that I always thoroughly rinse, and then soak, my nuts, can anyone think of a reason why this wouldn't be a good idea? Maybe a small amount of tiny grains would work their way into the nuts? But if it's pure silicon dioxide, shouldn't be a prob., right? Big "if", perhaps. If money weren't an object at all I would buy a bunch of desiccant packets, but why spend such a huge amount of money if cat litter would do the job perfectly!

I would still be concerned about the effects (chemical and aesthetic) of the litter. Desiccant packs are pretty cheap on Amazon; I toss one big oxygen absorber and one big desiccant pack into each gallon bag of nuts to be preserved.

 

Would be eternally grateful if someone could provide suggestions (off-list) about how I could get either suvorexant or zaleplon (Sonata) in Europe.

That seems best handled in a separate thread, no?

Share this post


Link to post
Share on other sites

Thanks Dean and Michael!

 

It seems like if you soak and rinse your walnuts there isn't any chance your nuts will have silica residue on them.

 

My concern was more about residue in them, i.e., pressed into the meat. But what I found earlier today at the local pet store, Trixie silicate pearls, will work fine! Nice big (2-3 mm) spheres.

 

But when I'm back from my little European hideaway, where ordering stuff from Amazon is a pain, I'll try some of the more conventional solutions you two have suggested.

 

I'm still not sure why you're reluctant to use the vacuum sealing solution. It prevents both ice buildup and oxidation.

 

Too unsettled geographically. Sick of buying transformers.... But I'll be settled soon.

 

 

IAC, experimental data trumps theory and extrapolation! You evidently missed my previous posting, in a thread on nuts [...].

 

Goodnes, no: saw and am grateful for that post. But the granularity of the analysis (and, judging by the ones I've seen -- many are behind paywalls -- the analyses on which the summaries are based) isn't the same as at least one of the olive oil studies you referenced in your older post on olive oil freezing. Not to say that the criteria of freshness used by the Univ. of Calif. group aren't highly relevant (and, of course, as you have noted, the main jaw-dropper from the UC summary isn't about changes with freezing, but the realization that most nuts bought in stores are not "fresh" by most definitions of fresh...).

 

In other words, I'd love to see assays of a bunch of the phytochemicals in nuts some of us hope to benefit from pre- and post-freezing. But, like I said, I'm not too worried about it.

 

Would be eternally grateful if someone could provide suggestions (off-list) about how I could get either suvorexant or zaleplon (Sonata) in Europe.


That seems best handled in a separate thread, no?

 

 

Well, maybe. Certainly shouldn't be pursued here in this thread, though, I'd agree.

 

Zeta.

Edited by Zeta

Share this post


Link to post
Share on other sites

Well, gang, I'm feeling two things. First, I'm proud of my creativity in finding a very cheap and (from what I so far have gathered, theoretically, and, in a more limited way, empirically) effective solution to the problem of keeping nuts and lots of other things dry. (Certainly: anything that can be rinsed, to get possible dust off, is something the "pearls" could be used for -- though it's possible that the silica gel is pure enough that the dust wouldn't matter, but I don't want to take that chance). Silica gel cat litter works amazingly well!

 

But, second, I'm feeling like a complete moron, because the one thing for which it clearly is not a good solution is precisely that for which I most desperately (because of a coming massive increase in humidity, among other things) needed a solution: walnuts!! The pearls get stuck nooks and crannies in the walnuts (this would probably also happen with pecans). Arg!!! So now, for months, I'll be inspecting every walnut I eat, and cracking them apart to release the stuck pearls, until I've finished the 10 kg. of walnuts.... <Sound of "losing my mind" laugh.>

 

BUT, this is actually not so bad, I finally realized. In fact, it might even be a good thing, because I've realized that inspecting every nut carefully -- any kind of nut, esp. nuts that are prone to damage (in the form of [1] problems with the right level of drying, [2] oxidation, and [3] mold), such as walnuts is a good idea. Cracking them open gives a sense of what the flesh is like. I'm tossing about 1 out of 5-8 or so as a result of my now closer inspections (previously, with nuts from the same source, I was tossing 1 out of 10 or so). Of course, we -- or at least I -- still don't know how to assess the quality of walnut flesh. I broached the topic here, but later realized I don't know whether lighter flesh is always better than darker. Lighter almost always seems dryer, and that should generally be a good thing. (Though the Univ. of Calif. summary Michael pointed us to has a lower limit on optimal air moisture content for long-term storage of nuts.) That question of assessment of nut quality probably belongs in a different thread. I've written to the people at the Univ. of Calif. No response yet. If I get one, I'll report back. I may try writing to someone else there, or calling.

 

Zeta

Edited by Zeta

Share this post


Link to post
Share on other sites

Zeta,

 

Bummer about the cat litter getting into the nooks and crannies of the walnuts. I'll restrain myself from pointing out that this wouldn't happen with either Silica Gel Pad Dessicants or vacuum sealing  :)xyz.

 

 

BUT, this is actually not so bad, I finally realized.

 

Way to turn lemons into lemonade! 

 

I'm tossing about 1 out of 5-8 or so as a result of my now closer inspections (previously, with nuts from the same source, I was tossing 1 out of 10 or so).

 

Are these the Hagg Farm walnuts you're finding 15-20% 'rejects' by your current criteria? I'll be curious what they UoC folks say. Hopefully you're being overly pessimistic in your judgment of walnut quality...

 

--Dean

Share this post


Link to post
Share on other sites

No, I'm in Europe, and the cost of shipping from California would be absurd. The ones I have are organic walnuts from Uzbekistan, supposedly from the recent harvest, but I'm finding it hard to believe. They are nothing like the quality of the Haag Farm nuts. I may have been ripped off, at least with respect to the grade (but also possibly freshness -- but to determine this I need an answer to my question about flesh color and (seeming) dryness [1]).

 

I was told by the distributor that I would be getting Chandler light haves. The standard allows for a certain fraction to be amber (worse) instead of light. But the fraction that don't seem to be light is quite high. (But there's being dark because of age, and being dark because of ... whatever it is that creates variation in color during growth. [2])

 

On the other hand, it's possible that Haag Farm may be "anti-ripping us off": That is, although the Haags told me the standard of the nuts they were shipping would be light, I think they may actually be extra light!

 

I don't remember how many of the Haag Farm walnuts I tossed, but it was exceedingly few -- 1 out of 50 or so.

 

Zeta

 

[1] I wrote to Marita Cantwell

 

http://ucanr.edu/datastoreFiles/234-2753.pdf

 

Perhaps someone in the US could try emailing or calling her, or someone else?

 

[2] You can see here, for example (look esp. at the small A B C D picture below the main chart), that the darker walnuts clearly do not look old. Maybe they are, but I don't think so.

Edited by Zeta

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×