"2 Dos, 1 Don't" – Simple tips to cut onions without crying

"2 Dos, 1 Don't" – Simple tips to cut onions without crying

Why does cutting onions cause stinging eyes?

The cause is that onions release an irritating chemical that makes our eyes sting. Onions are mainly water plus some vitamins and sugar compounds.

They also contain compounds including sulfur, a natural chemical found in many odorous substances, such as the spray of a skunk that smells like rotten onions and garlic. This is a way for plants to defend themselves by creating a repellent against organisms that might attack them. Other plants have thorns or prickly leaves, or are made of special cells that make them hard to chew.

A sulfur compound in onions, called propyl sulfoxide, escapes into the air when you slice an onion.

Accordingly, when it comes into contact with moisture, such as water vapor in the air or the natural moisture around your eyes, it turns into sulfuric acid. Sulfuric acid has a pungent odor and irritates the eyes, so they produce tears to wash it away.

If your eyes are already watering while cutting onions, do not use your hands to wipe the tears. This only makes the eyes sting more as your hands, covered in onion chemicals, will come into direct contact with the eyes, according to The Daily Meal.

How to slice onions without crying

Onions stored for a long time usually have higher sulfur concentrations than freshly harvested ones. For optimal results, you can combine 2-3 methods (such as chilling and using a sharp knife) to make the cooking experience more relaxed.

Chew continuously

Chewing gum or any food in your mouth encourages you to breathe through your mouth, thereby absorbing tiny droplets before they fly up to your eyes.

Put onions in the fridge before cutting

Chilled onion cells react more slowly when cut. Therefore, put onions in the refrigerator for at least 30 minutes before cutting and peeling, or put them in the freezer for 10-15 minutes (depending on the size of the onion).

Illustrative photo

Cut onions under water

Cutting onions under water or under a running tap will also help significantly because the water will dissolve the sulfur compounds before they can reach your eyes.

Rub potato slices on both sides of the knife

Use a fresh potato slice to rub both sides of the knife, then cut onions or peppers freely without worrying about stinging eyes.

Hold bread in your mouth

There is a small trick: if you hold a slice of bread (or any type of food) in your mouth while cutting onions, you won't get stinging eyes. This tip originates from the notion that if you do something that forces you to breathe through your mouth, the nose will be less stimulated and therefore you will produce fewer tears.

Vinegar

Spray the cutting board with a 50/50 mixture of vinegar and water because vinegar has the ability to stop the sulfur reaction. If the above mixture is not effective, try using only vinegar to spray on the board. However, this may affect the flavor of the cooked onions.

Use hot steam

To avoid stinging eyes, you just need to cut onions where there is rising hot steam, such as near a boiling kettle.

Chill the onion

One of the most effective methods is to put the onion in the freezer for about 15-20 minutes before cutting. At low temperatures, enzyme activity is significantly inhibited, while also reducing the evaporation rate of sulfur compounds. This is a way to slow down the chemical transformation right from the start.

Use a very sharp knife

Using a sharp knife is a decisive mechanical factor to limit eye irritation. A sharp blade will cut through tissue fibers decisively, minimizing the squeezing and crushing of cells. The less damage to the cells, the lower the amount of enzymes released into the environment. Conversely, a blunt knife will "crush" the onion surface, pushing the pungent gas levels to the maximum.

Turn on a fan

Turn on a fan in the same direction you are sitting to blow away the onion droplets released when cutting.

Cut onions under a tap

Many experienced chefs often cut onions under a gently running tap or in a basin of clean water. Since the stinging compound has good water-soluble properties, the liquid environment will absorb the gas as soon as it leaves the cut surface, preventing it from rising to the eyes.

If you don't want to cut in water, you can turn on a small fan blowing sideways across the cutting board area. The airflow will push the gas molecules away from your line of sight.

Apply vinegar to the cutting board or knife

An acidic environment can reduce enzyme activity. Applying a little white vinegar to the surface of the knife or cutting board before cutting will change the pH at the cut surface, partially blocking the reaction of the alliinase enzyme. This small tip is simple but brings surprising effectiveness.

Keep the onion root:

Usually, the root part of the onion has the highest concentration of sulfur compounds. Therefore, a classic chef's tip is to cut the top first, peel, dice, and leave the root part to be cut last (or discarded whole).

Wear eye protection

Another simple way to protect your eyes from the attack of pungent fumes from onions is to wear glasses to protect your eyes. Swimming goggles or gardening glasses both work, as long as they seal around the eyes.