What Is Ascorbic Acid (E300)?

What is ascorbic acid?

Ascorbic acid (E300, L-ascorbic acid, vitamin C) is a water-soluble vitamin used in the food industry for three different purposes: antioxidant, flour improver and nutrient fortifier. It is a white to slightly yellowish crystalline powder; about 33 g dissolves in 100 ml of water and the solution is acidic (pH 2.1–2.6). It is sensitive to heat, light, oxygen and metal ions (especially copper and iron).

Three different functions

As an antioxidant it binds oxygen and delays colour loss and flavour deterioration in juices, frozen fruit and vegetables and fatty products. As a flour improver it converts to dehydroascorbic acid in the presence of oxygen in the dough and accelerates disulphide bond formation between gluten proteins, increasing dough elasticity and gas retention and thereby bread volume. In cured meat products it speeds the reduction of nitrite to nitric oxide, making the cured colour fast and stable and reducing nitrosamine formation.

Applications and typical rates

20–100 ppm (on flour) as a flour improver in bread and bakery; 100–500 mg/l as antioxidant/fortifier in juices and beverages; 300–500 mg/kg in cured meat products (per regulation); 0.1–0.5% as a dipping solution for frozen fruit and vegetables; per the declared dose in dietary supplements. Overdosing to compensate for processing losses is common.

Grade selection: fine powder, granular, coated

Fine powder dissolves quickly and is preferred in liquid systems. The granular form reduces dust, flows well and prevents segregation in dry mixes. Coated grades protect ascorbic acid from moisture and oxygen and extend shelf life in dry mixes and tablets. Flour improver applications generally use fine powder or a premix diluted with a carrier.

Technical properties and quality criteria

Check purity (99–100.5%), moisture (≤ 0.4%), specific optical rotation (confirming the L form), pH, heavy metals, lead and arsenic, residual solvents, particle size, microbiological values and pharmacopoeia/food-grade conformity statement (USP, E.P. or FCC). A non-GMO statement is requested in many markets because production is fermentation-based.

Wholesale sourcing: price and minimum order

The wholesale price of ascorbic acid depends largely on Chinese production capacity and fermentation raw material costs; the market shows marked periodic swings. Origin, pharmacopoeia grade, particle form and order quantity all affect the price. The typical minimum order is 100–500 kg. PERDIST identifies the grade suited to your application, compares sources and provides a written quotation with documents.

Frequently asked questions

Why is ascorbic acid used in bread?

It acts as an oxidant in the dough, strengthens the gluten network and increases gas retention, producing higher volume and a more even crumb. It is effective at very low doses of 20–100 ppm.

What is the difference between ascorbic acid and sodium ascorbate?

Sodium ascorbate (E301) is the sodium salt of ascorbic acid; it has a neutral pH and is preferred in meat products where acidity is unwanted. Their functions are similar.

Is there loss over shelf life?

Yes; heat, light, oxygen and metal ions degrade ascorbic acid. An overage is planned in the formulation so the declared vitamin C value holds to the end of shelf life.

Specification summary

The values below come from the Ascorbic Acid page of the PERDIST catalogue and are confirmed per batch with the specification and certificate of analysis on every shipment.

Field	Value
Typical properties	Purity 99–100.5%, moisture ≤ 0.4%, white to slightly yellowish crystalline powder, water solubility about 33 g/100 ml, heavy metals ≤ 10 mg/kg, pH (5% solution) 2.1–2.6. Values vary by supplier specification.
Applications	Juices, nectars and beverages, bread and bakery (flour improver), cured meat products, frozen fruit and vegetables, dietary supplements, fortification of breakfast cereals and dairy.
Formulation note	Sensitive to heat, light and metal ions; overdose to compensate for processing losses. Typical use 20–100 ppm as flour improver, 100–500 mg/l in beverages, 300–500 mg/kg in meat products (per regulation).
Shelf life and storage	Typically 24–36 months in unopened packaging; store dry, cool, sealed and away from light.
Packaging	Typically 25 kg kraft bags or cartons with PE inner liner; pallets of 500–1000 kg. 1–5 kg packs considered on request.
Minimum order	Usually 100–500 kg; smaller quantities are stated in the quotation depending on product and supplier.
Origin	Common origins: China, European Union. Documented per lot in the quotation.

Documents to request from the supplier

The permitted food category, the maximum level and the label wording.
Activity units or purity, and which carrier the preparation uses.
Batch certificate of analysis and origin document, showing the number of the batch shipped.

For supplier selection, auditing and the approved supplier list, see the supplier evaluation and approval guide.

Sample and approval steps

The steps from requesting a sample to the application trial and keeping a reference sample are set out in the ingredient sample evaluation and approval guide.

Regulatory and documentation context

Additives and processing aids follow the Turkish Food Codex regulation on food additives and, in the EU, Regulation 1333/2008 for permitted uses and maximum levels. Confirm the permitted food category and the label wording in writing before use.