Does heat destroy nutrients in fruits?

The elderly with weak gastrointestinal functions and dental problems are reluctant to eat fruits in winter. Some elderly people choose to eat heated fruits, believing that cooked fruits are good for health. While others worry that the high temperature will lead to the loss of nutrients. Does heat destroy nutrients in fruits?

 

Eating cooked fruits is not unusual in daily life, as we have Beijing pear soup, apricot juice, pineapple rice, and crucian carp soup with papaya. The heating reduces the firmness of fruits, makes them soft and easier to chew, it also softens the fiber, activates the enzymes and kills pathogenic bacteria. Therefore, cooked fruits are appropriate for people with weak digestive functions.

 

Soluble sugar is an important indicator to measure the quality of fruits. Fruits with high soluble sugar taste sweet and delicious. Heating will greatly increase the content of soluble sugar in fruits, making them taste sweeter.

 

 

When fruits are heated at a high temperature for a long time, the content of vitamin C will be reduced. Heating will promote the aerobic oxidation of vitamin C. As the temperature increases, the oxidation rate gradually accelerates as well.

 

However, the vitamin C content in such fruits as apple, peach, pear and banana (4 to 8 mg per 100g)  is far less than that in bell pepper (130 mg per 100g), Chinese kale (76 mg per 100g), and pea seedling (67 mg/100g). Although heating will cause the loss of vitamin C in these fruits, the loss of minerals, dietary fibers and antioxidant substances is not obvious after heating. For fruits with rich vitamin C, such as winter jujube and kiwi fruit, it is better to eat them without heating.

 

 

The fruits that can be heated are normally thick and firm in skin and crunchy and hard in flesh, such as peach, plum, jujube and greengage, pome fruits like apple, pear, and citrus fruits like orange, tangerine, and grapefruit. After heating, the skin color of these fruits darkens, but generally their taste and appearance will not be affected. However, fruits with thin and delicate skin, such as mulberry, strawberry and fig, may turn mushy after heating, so they are often served as jam.

 

Fruits can be cooked by steaming, boiling, baking or microwave heating. The heating time depends on personal preferences. Generally, heating the fruits for about two minutes after the water boils will make them warm, delicious and juicy.