# crystals II **URL:** \ **Category:** Factual Questions\ **Created:** [September 18, 1999, 5:31am UTC](https://boards.straightdope.com/t/crystals-ii/3293 "1999-09-18T05:31:00Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![mikan](https://avatars.discourse-cdn.com/v4/letter/m/cc9497/32.png) [@mikan](https://boards.straightdope.com/u/mikan)\ **Post date:** [September 18, 1999, 5:31am UTC](https://boards.straightdope.com/t/crystals-ii/3293/1 "1999-09-18T05:31:00Z")
Since you all (well, you know who you are) answered my crystal vs. glass question with such clarity, I think it’s time for another question related to crystals (of the Folger’s variety): how do they make instant coffee? Obviously it’s not just a bunch of smashed up coffee beans; it’s some kind of “reconstituted” product (bleh!). Anyone know the nitty-gritty of how this is done? (And yes, if anyone knows what those Folger’s crystals are for, please do tell.) ---
**Author:** ![Doobieous](https://avatars.discourse-cdn.com/v4/letter/d/da6949/32.png) [@Doobieous](https://boards.straightdope.com/u/Doobieous)\ **Post date:** [September 18, 1999, 5:41am UTC](https://boards.straightdope.com/t/crystals-ii/3293/2 "1999-09-18T05:41:00Z")
Its freeze dried coffee. I am not sure on the specifics, but usually it involves freezing the liquid, then applying a vacuum to evaporate the water, and leave the good stuff, etc. Sorry if this isnt that great :). I dont know what the crystals are though. ---
**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\ **Post date:** [September 18, 1999, 5:54am UTC](https://boards.straightdope.com/t/crystals-ii/3293/3 "1999-09-18T05:54:00Z")
I couldn’t swear to it (i.e. WAG alert! See the sig.), but freeze-dried coffee was a Big Deal when it first came out, at least according to the ads. That suggests that previous versions of instant coffee were made some other way. Here comes the WAG: I know that a lot of concentrates are made by spraying the hot solution into a current of hot air, so the water evaporates. Coffee could be concentrated the same way, then dried completely in trays and ground to powder. ## It doesn’t really matter; instant tastes pretty horrible anyway. Bob the Random Expert “If we don’t have the answer, we’ll make one up.” ---
**Author:** ![Poto](https://avatars.discourse-cdn.com/v4/letter/p/7ab992/32.png) [@Poto](https://boards.straightdope.com/u/Poto)\ **Post date:** [September 18, 1999, 11:48am UTC](https://boards.straightdope.com/t/crystals-ii/3293/4 "1999-09-18T11:48:00Z")
Just to clrify, freeze dried means just that.A frozen coffee or other solution is exposed to high vacuum where the water evaporates and a solid is left behind. It’s probably how they prepare things like insulin and interferon, for storage as solids.