Denseman on the Rattis

Formerly known as the Widmann Blog


Where can I buy food-grade caustic soda?

Originally uploaded by adactio

In southern Germany, Brezeln are a beloved type of bread.

Being half Swabian myself (and the great-grandson of Stuttgart’s best Brezel baker), of course I miss them, and I would love to be able to bake them myself.

I’ve sometimes baked some with Miriam (my sister), boiling them in a mixture of natron and water, and although the taste was OK, they didn’t get the proper dark-brown colour.

However, I’ve now found a recipe that looks like it might be just what I’ve been looking for.

It tells you to soak the unbaked Brezeln in a strong caustic soda solution, and it says you can either get this at a pharmacy or a baker’s shop. (“36 % Natronlauge bekommt man aus der Apotheke oder vom netten Bäcker, der einen etwas abfüllt.”)

However, when I googled caustic soda, all the shops that sell it in the UK (such as Boots) seem to be selling it as a drain cleaner, and I have my doubts it’s really food-grade caustic soda.

If I’m willing to buy 10 metric tonnes, I can get it, but I’m not sure I can eat that many Brezeln. 🙁

Any ideas?

15 thoughts on “Where can I buy food-grade caustic soda?

  • What would make it “food grade”? Would the British sort be so tainted as to spoil the taste? This might be a question of culture rather than chemistry. The fact that it’s sold as drain cleaner obviously reflects the fact there’s no culinary demand for it, just as when I was a kid olive oil was bought in small bottles at the chemists (Boots again) as a treatment for skin complains or earache. We would never have dreamed of cooking with it, but it might well have been fine for that.

  • If it’s pure enough, I’m sure the drain cleaner would work fine. However, it might contain impurities or additives that would make it inedible, and if it’s not food-grade, it would not necessarily be declared on the packaging.

  • Ah yes, a question of labelling as much as anything else. Even salt has a list of ingredients nowadays.

  • Hmm, umiddelbart ville jeg nok holde mig fra rengøringsmidlet, der formodentligt indeholder andre uønskede stoffer; men hvad er det egl lavet af rent kemisk? For måske kan du bare få det på apoteket eller i en dansk Matas?

  • Alt, jeg ønsker, er en 38% NaOH-opløsning. Det skulle jo være let nok. 😉

  • Hmm, spørgsmålet er, om det i virkeligheden er så svært at fremstille i virkeligheden. Hmm, går jeres børn ikke i skole og har kemi? Dér må da være en kemi-lærer, som kan hjælpe jer.

  • Perfect, except that their minimum order is £50, which is a LOT of caustic soda! 🙁

  • Have you had any luck? I’m looking too. My Brother, studying for his Doctorate in Chemistry, has been helping me but there are few places around that sell any grade. I’ve seen some analytical grade which would do the job for £15 including postage, but I’m hopign to find a smaller quantity, locally.

  • No, I haven’t found anything at a reasonable price yet. 🙁

  • I’ve also been researching this… if all else fails, I’ll have to ask my German friends to bring some back after trips home! Not sure what the hand luggage restrictions on this kind of stuff is…

    Have you come across this site? That almost looks right, but I *would* feel safer seeing some sort of “food grade” designation.

  • hi, this is Nancy from Shenyang Sasuol Chemical company , a proffessional chemical company in china, Enjoying rich resource and convenient transportation, our factory has powerful technology capability, complete production line, perfect testing method and quality assurance system.

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  • Hi,
    I’m also looking for food grade lye to try the correct pretzel recipe. Did you find any? Do you want to split the cost with someone else and order some from the U.S? I am interested if you are?


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