Using hydrogen peroxide.
Apply a lot of hydrogen peroxide (40 volumes) to the yellowed plastic area using a brush or cloth. Ensure that you spread the product evenly over the entire surface.

3. Putting Plastic Wrap on Top
After putting on the peroxide, cover the area with plastic wrap. This helps the peroxide stay in touch with the plastic and stops it from evaporating too fast.

4. Being in the Sun
Put the device in the sunlight, if you can. Sunlight makes hydrogen peroxide work better, making teeth whiter faster. Leave the object in the sun for around one hour.

Taking off the plastic wrap and cleaning.
After one hour, take off the plastic wrap and clean off any extra peroxide with a wet cloth. Keep doing the same thing again if needed until you get the outcome you want.

More Advice
Doing it again: If the yellowing is severe, you might need to do the process more than once.
Try the hydrogen peroxide on a small spot first to make sure it doesn’t cause any negative reactions before using it on the whole surface.
Extra Protection: To avoid yellowing, keep appliances out of direct sunlight and think about using covers to protect them. DIY Options
If you can’t get 40-volume hydrogen peroxide, you can use homemade options to whiten yellowed plastic on appliances.

Mix baking soda and vinegar to create a paste. Apply the paste to the yellowed area and rub it in. Wait for 15-20 minutes before washing it off.
Hydrogen peroxide with 10 volumes is not as strong as 40-volume hydrogen peroxide, but it can still be used similarly when exposed to sunlight.
Mix lemon juice with baking soda to make a paste. Put it on the yellowed area, leave it for a few minutes, and then wash it off.
End
Making yellowed plastic on appliances white again is an easy process that can greatly improve how your kitchen looks. With hydrogen peroxide and some simple materials, you can make plastics look like new again and make your appliances last longer. Don’t forget to carefully follow the steps and keep your hands safe while working. By being patient and practicing regularly, you will see great outcomes and have a more cheerful kitchen for New Year’s Eve.