As a nutritionist with a focus on micronutrients, I'm often asked about the stability of vitamins in various conditions, including the effects of temperature on vitamin C. Vitamin C, scientifically known as ascorbic acid, is a water-soluble vitamin that plays a crucial role in the human body, from supporting the immune system to aiding in collagen synthesis. It is found in a variety of fruits and vegetables, and it's also commonly used as a dietary supplement.

The degradation of vitamin C is a topic of interest because it is sensitive to heat, light, and air exposure. While the melting point of vitamin C is around 190°C (374°F), which suggests that boiling vegetables won't destroy the vitamin C, the actual degradation process is more nuanced. Vitamin C begins to break down at temperatures above 40°C (104°F), and the rate of degradation increases with higher temperatures.

When cooking foods rich in vitamin C, it's important to consider the cooking method and duration. Boiling, for instance, can lead to significant losses of vitamin C due to its water solubility, as it can leach out into the cooking water. Steaming, on the other hand, tends to preserve more of the vitamin C content. Rapid cooking methods like stir-frying or microwaving can also help to minimize losses.

Another factor to consider is the acidity of the food. Vitamin C is more stable in acidic environments, which is why it retains its potency better in acidic foods like oranges or tomatoes. Conversely, in alkaline conditions, it degrades more quickly.

Storage and preparation also play a role. Prolonged storage of foods, especially at room temperature, can lead to the degradation of vitamin C. Refrigeration slows down this process, but it doesn't stop it entirely. Chopping or crushing fruits and vegetables can also increase the surface area exposed to air, accelerating the oxidation and degradation of vitamin C.

It's also worth noting that the form of vitamin C can affect its stability. Natural forms of vitamin C, such as those found in whole foods, are typically more stable than synthetic forms found in supplements. However, even within natural sources, the specific form of vitamin C can influence how it reacts to heat and other environmental factors.

In summary, while the melting point of vitamin C is high, indicating that it won't be destroyed by boiling, the actual degradation of vitamin C in food begins at much lower temperatures. The stability of vitamin C is influenced by a variety of factors including temperature, cooking methods, acidity, storage conditions, and the form of the vitamin itself.

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Vitamin C, as most of the vitamins, is soluble in water; one of the few vitamins that is not soluble in water is the vitamin D, which is fat soluble. The melting point of vitamin C is 190 --C (374 --F), which means the temperature at which you boil the vegetables cannot destroy the vitamin C.Sep 2, 2011read more >>