What is E300? (Food Additive Explained)
E300 is ascorbic acid — the same compound as vitamin C. As a food additive, it's used as an antioxidant to prevent foods from turning brown, losing colour, or going rancid. It's found in everything from fruit juices to cured meats and is considered completely safe.
What is E300?
Full name: Ascorbic Acid (Vitamin C)
E300 is L-ascorbic acid, commonly known as vitamin C. It's an essential nutrient that humans need from their diet (we can't synthesise it ourselves). As a food additive, it's typically produced industrially through bacterial fermentation of glucose. While it's chemically identical to the vitamin C in an orange, in food manufacturing it's used primarily for its antioxidant properties rather than its nutritional value.
What does E300 do in food?
E300 works as an antioxidant — it reacts with oxygen before the oxygen can damage the food. This prevents browning in cut fruit, colour loss in processed foods, and rancidity in fats and oils. In bread-making, it's used as a flour treatment agent to improve dough strength. In cured meats, it accelerates the curing process and can reduce the formation of nitrosamines (see E250). It's one of the most versatile food additives in use.
Where is E300 found?
E300 is commonly found in:
- Fruit juices and soft drinks
- Bread and flour products
- Cured and processed meats
- Frozen fruits and vegetables
- Baby food and infant formula
- Breakfast cereals and snack bars
Is E300 bad for you?
E300 is considered completely safe. It's vitamin C — an essential nutrient with well-established health benefits. EFSA has not set an ADI because it's not considered a health risk at any normal dietary level. Excess vitamin C is simply excreted by the body. It's one of the few food additives where the additive itself has a positive nutritional contribution, even when used primarily for its technical function as an antioxidant.
Why E300 matters for food choices
E300 is a good reminder that E-numbers are not inherently bad. Vitamin C as a food additive is safe, natural, and even nutritionally beneficial. However, its presence on a label still tells you something about the product — it means the food has been processed in a way that requires antioxidant protection. The key is always to look at the full ingredient list. E300 on its own is fine; E300 alongside a long list of other additives is a different story.
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