Why chilling of onoin avoid crying eyes?

Chilling onions does help reduce the intensity of the eye-watering effect, but it doesn't completely eliminate it. Here's why:

1. Chemical Reaction: When you cut an onion, you damage its cells, releasing a gas called syn-propanethial-S-oxide (SPSO). This gas is what causes the burning sensation and tears in your eyes.

2. Cooling Effect: Chilling the onion slows down the chemical reactions that produce SPSO. The cold temperature temporarily numbs the nerves in your eyes that are sensitive to the irritant, making you less likely to cry.

3. Enzyme Activity: The enzymes responsible for producing SPSO are less active at lower temperatures. Chilling the onion reduces the activity of these enzymes, resulting in a lower concentration of SPSO released.

4. Vaporization Rate: The cold temperature also reduces the rate at which SPSO vaporizes. Since there's less gas in the air, there's a reduced chance of it reaching your eyes and causing irritation.

While chilling onions can mitigate the eye-watering effect to some extent, it's not a foolproof solution. Some people may still experience irritation even with chilled onions. Additionally, chilling the onion may alter its flavor and texture, so it's important to consider this factor when preparing your dishes.

Here are some additional tips for reducing eye irritation while cutting onions:

- Use a sharp knife: A sharp knife creates cleaner cuts, releasing less SPSO.

- Cut the onion under running water: The water can help absorb the irritant gas and prevent it from reaching your eyes.

- Wear goggles or safety glasses: These provide a physical barrier between your eyes and the irritant.

- Use an onion chopper or food processor: These tools can help minimize your exposure to the irritant gas.