Foods high in mannitol

Where it turns up

• •Mushrooms — button, chestnut and portobello, fresh or dried, and the dishes built on them: risotto, mushroom sauces, soups and stock. Two exceptions worth knowing: oyster mushrooms carry very little, and tinned mushrooms lose much of theirs into the brine, so drained and rinsed they sit low.
• •Winter squash and celery — butternut, acorn, delicata and spaghetti squash all carry some, and celery does too. These sit well below mushrooms, and mostly climb once the serve gets big, so the portion column matters more here than the name.
• •Sweet melon — watermelon and honeydew, where mannitol sits alongside the fruit sugars.
• •Sugar-free confectionery — mints, chewing gum, sugar-free sweets. Mannitol is also the fine white powder dusted onto gum to stop it sticking, so it can be present without being the sweetener.
• •Fermented vegetables — sauerkraut and other properly fermented cabbage, where the bacteria that sour it turn the vegetable's own sugars into mannitol. It is the fermenting that produces it: the raw cabbage and cauliflower going into a vinegar-pickled mix like giardiniera are scored on other groups entirely, so check them on their own pages.
• •Sea vegetables — kelp (kombu) and wakame, and the seaweed salads made from them. Brown seaweeds store their energy as mannitol, so it's built into the plant itself. Nori sheets and roasted seaweed snacks come from a red seaweed instead and carry very little; in a kombu stock, most of the mannitol stays in the strip if it is lifted out.