Post Punk Kitchen Forum

I accidentally put them in unlabeled containers thinking I'd remember by the size of the container which one was which, but no such luck, immediate amnesia. Is there a way to tell the two apart? Most recipes call for slightly more of one than the other and I don't want to waste them since they're brand new.

You could probably do an iodine test with a dilute of each flour in water. The starch in both potato & tapioca will react to the iodine and turn dark blue, but if you continue to add iodine, the Vitamin C present in the potato starch (and not tapioca) will change the color of the iodine again. Or something like that... I think I'm remembering this right? Any chemists here want to chime in?

I'm guessing there's another, simpler way.

Hmm, that's tricky and I'm not really sure if this would work, but if I did that I'd look for a recipe that relies heavily on one, say tapioca, and try it with one of the mysterious powders. If it comes out right, it's tapioca. If not, it's potato. Of course, it could be some other error, so it would probably work best if it's a recipe you're already familiar with.

I feel like they're probably different textures when you mix them with water...I can experiment when I get home if you want me to! I think I have both...

Tapioca should be glossier than potato starch when mixed in water.

Hm so look for glossiness? Anything telling about the taste? I would taste them to check, but afraid to see what tapioca tastes like, ugh. HA. If you could test it out, that would be awesome!

have you never had tapioca pudding? it's nomtastic!

i bet if you cooked some up and tasted them, you'd be able to tell. (i'd guess potato starch is slightly saltier whereas tapioca is slightly sweeter)

Argh, I can tell them apart but I don't know if I can explain how. I use them both at work and potato starch tends to clump together more when pouring whereas tapioca isn't quite as clumpy, more powdery. I doubt this really helps since it's only noticeable after measuring them hundreds of times. In any case they're pretty similar and I don't think anything would be ruined if you mixed them up.

Wet tapioca starch will look like boogers. Potato will be a slurry.