Why Bananas, Potatoes and Apples turn brown after being cut?
“Eeshan, do you know why bananas, potatoes and apples turn brown after some time outside?” asked Mrs. Iyengar.
“I can guess they undergo some kind of reaction,” replied Eeshan.
She said, “Yes. Complex chemical reactions go on in these foods all of the time – even if you’re not cooking them. They all contain an enzyme which triggers the release of ethylene when they come in contact with air.
It ripens them and turns them brown with over-ripening. That is why I wrap them in plastic sheets- so they last longer.
Many kinds of food can be preserved by salting them. Salt extracts the water out of the food, making it dry and deters the growth of bacteria.”
“All this knowledge from just watching you cook! It’s incredible, Ma!” marvelled Eeshan.
His mother smiled and said, “Let me make you some pancakes for breakfast. Do you know why I mix the baking powder in them?”
Eeshan shook his head to imply no.
His mother continued, “Milk is acidic in nature. You told me that baking powder contains sodium bicarbonate. The base and the acid react to give carbon dioxide. That makes the pancakes nice and fluffy. Just like this.”
Mrs. Iyengar served Eeshan a pancake and topped it with a little honey.
Eeshan said, “Your cooking is anyway great, mother. Now I get to learn every time I see you cook and you can trust that I will only give you a positive reaction!”
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