Black beans

Black beans is notable for FODMAPs, oligosaccharides, nickel and oxalates. Clear on lactose, histamine, gluten, fructose, sorbitol, sucrose, tyramine and salicylate.

Yes — Black beans is high in FODMAPs. Black beans are among the highest-GOS beans, and they are usually cooked in the liquid rather than drained from it - a pot of frijoles keeps its cooking water on purpose, because that is where the flavour went. The technique that makes them good is the one that keeps the GOS in the bowl.

Yes — Black beans is high in oligosaccharides. Same reason as the FODMAP level: black bean GOS, and a cooking tradition that keeps the liquid on purpose. Where the water stays, the oligosaccharides stay. Pulse oligosaccharides are water-soluble, and that is the practical point: the level here follows work on pulses AND on what cooking does to them, because soaking and boiling move part of them into water that is usually thrown away.

Black beans contains moderate levels of nickel. Black beans take nickel up through urease like every legume. Canned and rinsed they measure lower than dried and boiled at home, because some of the metal leaves with the cooking liquid.

Black beans contains only low levels of oxalates. Black beans are low in oxalate as they are actually eaten, because boiling carries the soluble fraction off in the water; dry, before any of that, the load is moderate. Which makes the cooking liquid the thing to watch - the dark broth that gives a feijoada or a pot of Cuban beans its colour is where the oxalate went, and keeping it puts back what the boiling removed. Draining is the whole lever. Canned and rinsed has had it done for you. Quinteros measured that on the pulses themselves and found every cooking method lowers the soluble fraction, with microwave and industrial processing more effective than ordinary domestic cooking. Amounts vary by brand and recipe, so always check the label of the exact product.