Alliums

Within the allium plant family are garlic, onions, shallots, scallions, scapes, ramps, leeks, and chives, all of which contain sulfuric compounds (alk[en]yl-L-cysteine sulfoxides, or ACSOs) that give them their distinctive flavor. When an allium is cut or bruised, the ACSOs are released from the plant’s cells and undergo a series of chemical reactions to produce flavor compounds that we can smell and taste. The raw bite of an onion in a salad might seem harsh when compared to fresh scallions, but when onion slices are slipped on top of a burger, they create a delightful burst of heat. Garlic has four ACSOs while an onion has three. This is why they taste unique but familiar.