Split pea

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

Split pea contains moderate levels of FODMAPs. Split peas are dried peas with the skin removed, and they are eaten as soup - by the bowl, thickened, with the cooking water kept because that is the soup. None of the FODMAP is drained away, which is what separates split pea soup from a rinsed can of chickpeas.

Split pea contains moderate levels of oligosaccharides. Same reason as the FODMAP level: split pea GOS, in a dish built on keeping the cooking liquid. Soup is the worst format for a water-soluble oligosaccharide, because nothing is poured away. The pea's oligosaccharides are the raffinose family, measured in the seed itself. They are what a legume stores for its own germination, which is why they sit in the seed and not in the pod.

Split pea contains only low levels of histamine. Split peas carry little histamine dry, and boiling lowers it further - amines leach into the cooking water and are poured away. Sprouting does the opposite: a germinating seed produces amines as it wakes up, so sprouts are a different food here from the pulse they came from.

Split pea contains only low levels of tyramine. Split peas are low as a dry seed, and boiling lowers it further - amines leach into the water. Germination raises it instead, which is the one preparation to watch: a sprout has spent days doing what a dry seed cannot. Amounts vary by brand and recipe, so always check the label of the exact product.