Vitamin C
Vitamin C is a nutrient in fruits and vegetables that breaks down when exposed to heat or air.
Fresh strawberries in a bowl hold their vitamin C like bright marbles packed tight inside. Heat the bowl on the stove and the marbles start to vanish one by one. Leave the bowl open in air for a few hours and more marbles fade away. A sealed bowl in the fridge keeps nearly all the marbles in place.
Explaining vitamin c by grade level
Oranges and carrots have vitamin C inside them. Your body needs it to stay strong and heal cuts. When you cook food in hot water, the heat breaks down the vitamin C. That means raw fruits give you more of it than cooked ones do.
Projects that explore vitamin c
Heat and processing break down vitamin C, so fresh-squeezed orange juice tends to hold more of this nutrient than bottled juice that has sat on a shelf. A vitamin C indicator solution makes that difference visible. It starts blue, and you add drops of juice one at a time until the color disappears. Fewer drops means more vitamin C remains in the sample.
Vitamin C breaks down when exposed to heat, and both the cooking method and the time matter. Boiling and steaming carrot cubes at 15, 30, and 45 minutes, then measuring the remaining vitamin C with an iodine titration test, shows which method preserves more of this nutrient. Comparing all six samples reveals how longer exposure to heat increases the breakdown.
Cooking may cause vitamin C to break down, which means heated samples could contain less of this nutrient than raw ones. You blend raw tomatoes and cherries with water, split each into two portions, and heat one of each on a hot plate while the other stays raw. An iodine-starch solution that turns dark purple measures what remains — as drops of each fruit sample cause the color to fade, more fading means more vitamin C is present. Comparing raw and cooked samples reveals whether heat reduced the amount.