Daily tip - how to make the tears stop

On more than one occasion, I've stood over the cutting board with tears streaming down my cheeks until I learned the following tricks. Why? Onions, like all members of the allium family are full of amino acid sulfoxides, which give these vegetables their distinct bitter flavor. When onions are sliced, enzymes called allinases are released and react with the sulfoxides and create sulfenic acids. Sulfenic acids are extremely unstable and can form syn-propenethial-S-oxide. Why does this matter? It's this chemical that irritates your cornea and ciliary nerve in your eye and makes you tear up.

How to resolve this? There's a few options. Refrigerate onions thoroughly, or stick them in the freezer for just a few minutes (be sure not to let the onion freeze) before you slice them. Another alternative is to cut off the top but leave the root on the onion. Or, you can cut onions under water or soak them before slicing. Interestingly, onions with a higher water content (Walla Walla, Vidalia, etc.) do not cause as many tears. Of the "normal" generic onions, white onions have the most water, followed by yellow and then red.

Following yesterday's tip - another way to prevent tearing is to use a very sharp knife. A sharp knife does less damage to the onion's tissue and thus doesn't release as many allinases.

The most basic way to stop the watershed? Cut the onions in a well ventilated area.