The end of an onion that you should cut first is the pointy stem end, although you can also cut the root end of the onion if you prefer.
Both ends of the onion can be cut based on your own preference.
Some people prefer cutting of the stem end of the onion first for a stable base and others find it easier to start with the root end.
I like to start with the stem end when cutting and cut about half an inch, which gives you a good stable base when you're ready to cut the onion down in half.
Chefs cut onions by using a sharp knife to make precise cuts in the onion while also keeping the root end of the onions intact to hold the onion together.
A sharp knife is key in reducing the tears from onions and making good cuts.
Using a dull knife to cut onions will smash the onions cells and release more of the irritants and lead to more tears.
Chefs also remove the top and root ends of the onion, but they also leave the root end partially intact to hold the onion together and they also remove the papery outer layers of the onion as they can also be slippery and hard to work with.
Chefs will cut onions by slicing the onions or even dicing of the onions.
To slice the onion, cut the onion in half through the root end of the onion.
then place one half cut side of the onion down on a cutting board and make horizontal cuts, that are parallel to the cutting board and be careful to not cut all the way through the root of the onion.
Then slice the onion vertically by making vertical cuts, but don't cut all the way through the root as the spacing of these cuts in the onion will determine the thickness of the slices of onions.
Then slice through the onion perpendicular to the previous cuts to create slices and the root end will hold the onion together, making it easier to control the cuts and minimize the tears.
To dice onions, follow the same steps as you would for slicing, but make the horizontal and vertical cuts of the onion closer together for a finer dice.
Then slice through the onion, perpendicular to the previous cuts, to create small, diced pieces.
Chefs cut onions without crying by chilling the onions before cutting.
Other ways that chefs cut onions without crying are by using a sharp knife and cutting the onions under water or even cutting the onions near a wet paper towel.
You can also wear goggles to prevent tears when cutting onions as the goggles protect your eyes almost completely from the irritating compounds.
To cut an onion without it burning your eyes you can chill the onions in the refrigerator for awhile before cutting them or soak them in some cold water for a few minutes or even cut the onions under some running water.
You can also cut an onion without it burning your eyes by placing a wet paper towel next to the onion when cutting it to help attract the chemical causing irritant and direct it away from your eyes.
Putting a wet paper towel next to an onion when cutting the onion does really work to help reduce tears.
Onions release the chemical irritant when they are cut and the moisture from the wet paper towel attracts the irritant and compound and draws it away from your eyes.
The reason why onions make you cry when you cut them is because of the chemical compound called lachrymatory factor LF that is released when the onion is cut.
Onions contain a chemical compound called LF or lachrymatory factor which is a sulfur containing compound which irritates your eyes and causes your eyes to produce tears.
When you cut into the onion it releases the lachrymatory factor LF sulfur containing compound.
Also when you cut into an onion, the enzymes that are within the onion cells are activated.
Then the enzymes react with the sulfur compounds in the onion, which produces the LF or lachrymatory factor.
The lachrymatory factor compound is volatile and easily evaporates into the air.
Once it evaporates into the air the lachrymatory factor compound then comes into contact with your eyes and it also irritates the nerve endings and causes a stinging sensation and tearing or crying.
To reduce the tears from onion cutting you should use a sharp knife to minimize damaging of the onions cells.
Chilling the onions before cutting them and even soaking the onions in cold water for a few minutes or even cutting the onions under running water can also help prevent the tears or crying when cutting onions.
You can also wear some goggles to reduce the contact of the compounds to the eyes.