alliaceae allium allium cepa brown onions bulbs bulk common onions cultivars Dirt dirty edible flavonoids flavor flavour food growing growth healthy layers lines medicinal mild nutritious odor odour onion oval-shaped paper thin papery skin peel peeling pickling pungent quantity raw round skins soup vegetable tangy tasty thin vegetable allium-cepa brine brown-onions common-onions moist onions Pickled pickled-onions preservation Preserved salt savory savoury small solution sugar vinegar green leaves salad vegetable shooting shoots white circles cut half halved stir fry vegetable