Why and how does vitamin oxidise when exposed to oxygen?
Vitamin C is ascorbic acid. How and why it becomes oxidized is because it looses hydrogen molecules. It loses hydrogen on the hydroxyl group and creates dehydroascorbic acid and water. In more detail, it happens because it doesn't take a very high activation energy for this to happen, so it will oxidize under normal temperatures and pressures. A completed octet of electrons in the outermost shell of an atom is the most stable. Ascorbic acid becomes more energetically stable by becoming oxidized. http://www.plantstress.com/Articles/Oxid...
How does Vitamin C prevent applesauce from turing brown?
A very good description of ascorbic acid (vitamin C) and the oxidized form of ascorbic acid known as dehydroascorbic acid can be found on Wikipedia. Ascorbic acid is highly reactive to oxygen and works as a sacrificial body to mop up oxygen before it can react with other chemicals. Ascorbic acid is commonly used as a preservative not only to reduce browning of foods, which is the result of oxidation of iron in the applesauce, but also to extend the shelf life of foods. http://en.wikipedia.org/wiki/Ascorbic_acid
Why does vitamin C darkens my skin? I use vitamin C suspension 23% + HA spheres 2% at night and I use sunscreen daily.
Vitamin C in the form of ascorbic acid oxidises easily to dehydroascorbic acid, which has an orange-brown colour. It does this when it’s stored in water, as well as on your skin. In this form, it further decomposes into erythrulose. Erythrulose is used in tanning lotions. So basically you are giving yourself a fake tan.To prevent the fake tan, you need to use different forms of Vitamin C that are less prone to oxidation. Ascorbyl Glucoside, tetra-isopalmitoyl ascorbic acid or ATIP, sodium ascorbyl phosphate, and magnesium ascorbyl phosphate are less prone to oxidation. Look for these ingredients in your skin care.For more info, check this website, https://labmuffin.com/vitamin-c-...
What are the best Vitamin C supplements?
HiYou can see a great comparison and ranking of the best vitamin C at SuppRank.com - our great supplement ranking site that shows an honest ranking of supplements based on actual lab tests, Reviews from multiple sites, quality check and many more factors - All in one place completely free.There are a few factors to consider when choosing a Vitamin C supplement:Forms of Vitamin C:Ascorbic Acid - The most common form of vitamin C. This is the proper chemical form of vitamin C Most vitamin C supplements are in this form, and are synthetic.Calcium Ascorbate - Better absorbed than ascorbic acid, and more gentle the stomach.liposomal vitamin C - less Common and harder to find. Fat soluble, and according to some increases absorption.2. The actual potency of the vitamin C and actual amount:From our research it seems that many supplements label claim is pretty far from what is found on objective lab tests. I addition many times there are added ingredients that add flavor or color that are not always healthy for us.From what we gathered these are the top 3 Vitamin C supplements (you can see a full list at our site)Natures-Way-Vitamin-C-10002. Twinlab-C-1000-caps3. Spring Valley Vitamin CI hope it answers your question.Have a great day.
Why does heat adversely affect Vitamin C?
Vitamin C is one of the least stable of all vitamins in solution and is oxidized readily in light, air and when heated. It is also water soluble. This means that heating in water, causes the vitamin to leach out of the food into the water and also to be oxidized, first to dehydroascorbic acid and then to diketogulonic acid. This last compound has no Vit C activity at all and is irreversible. However, normal cooking usually doesn't affect Vit C levels that much; the longer you cook and the higher the temperature you use, the more oxidation.
If I mix Vitamin C in a glass of 100°C, is the Vitamin C completely destroyed? Are there any techniques to preserve Vitamin C from heat?
The vit.C is destroyed by oxidation (hence is antioxidant protection properties - it gets destroyed instead of other molecules) and the chemical reactions involved usually occur faster when the temperature increases. So, to answer your question, the temperature is important, but it is also important to what oxidants are you exposing the Vit. C - what you are mix your Vit. C with in your hypothetical glass at 100 C. Of course, if you are mixing it with water, at 100 C it will be boiling - not much use in that. If you are mixing it in something else, then will depend a lot of what oxidants are present.THe way to preserving vit C from heat is not exposing it. There are some studies showing that adding sugar to fruit juices slows down the rate of decay of vit. C, but that will certainly not help at 100 C.
What is the maximum dose of vitamin C?
To bowel tolerance. That means, until you get diarrhea. Increase your intake gradually, preferably supplementing 4 - 8 times per day. Vitamin C washes out after a few hours, so rather than taking all at once, divide it. If you take Ascorbic Acid every 6 hours, start with 100mg each dose. Increase from 400 mg/day to 800mg/day to 1200mg/day to 1600mg/day. Increase each dose by 100mg until your stool gets soft, then let things stabilize. If your stool remains soft and is clean and well formed, you have found your (current) ideal dose.Focus on eating foods rich in natural vitamin C. Supplements tend not to provide important cofactors.