Hey emo, I have both kinds....gelatin and veg oil.....my gelatin ones melted right away in water but the veg-oil ones didn't.

PS....I have used both kinds (and still do) and haven't had any problems with them melting. I would make sure to keep your caps in the fridge to solidify the oil as well. But I can honestly say I don't even worry about what kind I am buying.....they both work fine for me.