freeze precip dryout in humid climate

[mad_banshee]

Maybe this has been talked about before, but I would appreciate any input on what I should do.

I've been very successful at pulling spice in the wintertime. Do the stb mix with naptha, freeze precip in glass baking pan, pour off excess naptha and dry with a fan upside down. Makes nice dry crystals in the cold dry weather.

Now I'm trying the same thing in the warm humid summertime, and so when I take the dish out of the freezer of course condensation forms all over it inside and out, and then the spice gets sticky/oily instead of dry flakey.
I'm thinking I should just cover it and let it sit until a very low humidity day comes about and try it again, but any thoughts of how to get around this problem would be appreciated.

 

[SWIMfriend]

It should be covered tightly in the freezer. When you take it out, allow it to warm up to room temperature before you remove the cover. If you do that you won't get any condensation.

 

[mad_banshee]

It should be covered tightly in the freezer. When you take it out, allow it to warm up to room temperature before you remove the cover. If you do that you won't get any condensation.

Thanks for the tip, but won't the spice likely melt back into the warming naptha as the dish warms up?

 

[endlessness]

in SWIM's experience of humid climate, yes it does melt back into the warming naphtha

So instead of doing this, SWIM would scrape the crystals quickly with the naphtha still inside, then pour it through a coffee filter attached to an improvised vacuum filtering.. This fast vacuuming dries the crystals before the naphtha can melt

If any spice does melt into the filter, specially if no vacuum is applied and its slower, then one would have to run hot naphtha through the filter to pick the melted crystals up.

good luck

 

[SWIMfriend]

It should be covered tightly in the freezer. When you take it out, allow it to warm up to room temperature before you remove the cover. If you do that you won't get any condensation.

Thanks for the tip, but won't the spice likely melt back into the warming naptha as the dish warms up?

The procedure I'm thinking of is:

1) Cover and place in freezer to allow precip.
2) Remove from freezer, quickly pour off solvent (and allow any precip to remain in dish) by lifting corner of cover
3) Put back in freezer again covered, but positioned in such a way that any remaining solvent can drain off and away from precips.
4) Take out again, lift corner of cover, pour off any remaining solvent, re-cover completely and allow to warm up to RT. When completely at room temp., then take off cover, allow the tiny bit of remaining solvent to evap, and scrape up spice. The main thing is that water won't condense onto the inside of your dish or your spice, if they're at room temp--even if humidity is high.

Another great solution is warrensaged's room temperature bestine recrystallization.

 

[Phlux-]

what swim does is this (mostly the same)

fp the naptha in a shot glass with cling wrap over it
once xtals are formed - remove the clingwrap and quickly pour off or suck out the naptha, recover and place back in the freezer just for a few minutes.
quickly remove shotglass from the freezer and scrape out the xtals onto your collection plate.

in a humid environment the xtals usually melt into a little puddle - leave the puddle overnight and xtals form - over the next few days the xtals grow bigger until all the melted spice is xtal again.

any glassware contaminated with spice can be cleaned with acetone which can be evaporated together in the same way.

 

[crakkbakk]

If one quickly pours the naphtha out immidently when pulling it out of the freezer this shouldn't be a problem? Then immigienylu scrape as many xtals as possible andleave jar upside down in freezer over a plate in freezer to drain naphtha and collect the rest later?

 

[mad_banshee]

The procedure I'm thinking of is:

1) Cover and place in freezer to allow precip.
2) Remove from freezer, quickly pour off solvent (and allow any precip to remain in dish) by lifting corner of cover
3) Put back in freezer again covered, but positioned in such a way that any remaining solvent can drain off and away from precips.
4) Take out again, lift corner of cover, pour off any remaining solvent, re-cover completely and allow to warm up to RT. When completely at room temp., then take off cover, allow the tiny bit of remaining solvent to evap, and scrape up spice. The main thing is that water won't condense onto the inside of your dish or your spice, if they're at room temp--even if humidity is high.

Thanks,
I tried that and it worked to some degree. The crystals still came out a little goopy, but not too bad.
It was SO much easier extracting and drying on a very cold winter day in a cold room with the windows open!
Will have to do a big extraction next winter!

 

[vegantoker]

I had this same problem with a flat glass dish I was trying to use. Spice kept melting when using the flat dish but not when I used mason jars.
The reason for this problem, I'm assuming, was not having an airtight lid on the flat dish which allowed moisture in and the quick warm up to room temp caused condensation inside the dish even if it was warmed without opening.

So if you think that might be why you or SWIY is having problems try this, it worked for me:

Freeze precip as normal but after pouring off the naphtha and putting it back in the freezer upside down for a bit (30 min to an hour) as normal, take the dish and put it in the fridge. I'm really not sure how long it needs to be left in the fridge as I went to work after putting it in. Maybe another 30 min to an hour would be enough but you may need to experiment.

Then I removed the lid and placed the dish upside down on a plate that fit under the dish in a way that allows airflow under the dish for another 20 min in the fridge.

Take the dish and plate out of fridge and put both under a fan for a hour or two.

Spice wont melt anymore. 8)

You guys are great, I would have been a member sooner but the registration would not work for me for about a week.
I look forward to becoming a active contributor. Thanks everyone for your great info when I was just a guest lurking the forum! My first two extractions went pretty well because of your info and after my first trip I'm in love with this stuff, just amazing.

Peace!