Rose petals

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

Rose petals contains moderate levels of salicylate. Dried petals used in blends and confectionery, and rosewater carries the same compounds in liquid form — easy to use generously without noticing. Paterson's spice assay gives a salicylate ceiling for the class and no figure for any one spice, so this level is an ordering.

Rose petals contains only low levels of histamine. Rose petals are dried and used as an infusion, so two dilutions apply at once: the flower carries no histamine to begin with, and steeping transfers only part of what a plant holds into the water.

Rose petals contains only low levels of oxalates. Rose petals are steeped and never eaten, and an infusion transfers only the soluble oxalate of what they hold. Rose water goes a step further: it is distilled, and oxalate does not travel with the steam, so that water carries none of it at all. Amounts vary by brand and recipe, so always check the label of the exact product.