Why do onions make you cry?
When an onion is cut open, the damaged cells release sulfuric compounds and enzymes into the air, irritating the eyes.
There are lots of hints and myths for preventing "onion tears" — from chopping them under water to holding a match between your teeth.
The National Onion Association advises chilling the onion for 30 minutes before chopping. "You're slowing down the cell's chemicals that produce the tears," said NOA spokeswoman Kim Reddin. Start cutting at the top of the onion, and don't cut into the root end at the base, because that's where more of the sulfides are. Use a sharp knife that slices cleanly, rather than ripping through the onion.
"The less cell damage, the less tears you're going to get," Reddin said.
Cook's Illustrated magazine staffers found the two best methods were to cover their eyes with goggles or to keep a flame (from a gas burner or a candle) near the cutting board. The flame oxidizes the sulfuric compounds and enzymes.
Patty Hartley of Utah Onions advises using the food processor or a hand-chopper gadget, so you don't have as much contact with the sulfides.
You can also use dried onion flakes in many recipes, such as soups and casseroles. (A jar on the pantry shelf comes in handy when you're out of fresh onions.)
Fresh onions, such as Vidalia Sweets are less pungent and give off less sulfides.
Pearl onions should first be blanched to loosen the outer layers for peeling, according to "Perfect Vegetables," by Cook's Illustrated magazine. Don't cook them any longer than 2 minutes in boiling water, then transfer to a bowl of ice water, and the skins will slip off.