Quick Facts
| CAS Number | 7695-91-2 |
|---|---|
| Molecular Formula | C31H52O3 |
| Molecular Weight | 472.74 |
| Pharmacopoeia | GB/USP |
| Packaging | 25 KG/DRUM |
Product Overview
Vitamin E was discovered in 1922 by Herbert Evans and Katherine Bishop at the University of California, Berkeley, who identified a fat-soluble "Factor X" essential for fetal development in rats. It was isolated in 1936 from wheat germ oil by Evans and Gladys Emerson and named "tocopherol" from the Greek tokos (childbirth) + pherein (to bear) + -ol (alcohol), reflecting its essential role in reproduction. Over subsequent decades, research revealed Vitamin E's fundamental identity: the body's primary lipid-soluble chain-breaking antioxidant, protecting polyunsaturated fatty acids in cell membranes from peroxidative damage.
Vitamin E 50% is a formulated adsorbate powder comprising all-rac-alpha-tocopheryl acetate uniformly dispersed on an inert carrier at 50% w/w potency. This presentation solves a fundamental manufacturing challenge: pure Vitamin E acetate is a viscous oil that cannot be dry-blended into powders, multivitamin tablets, or animal feed premixes. By adsorbing the oil onto a carrier matrix (typically silicon dioxide or starch), the 50% powder delivers easy handling, precise metering, and uniform distribution in dry systems — while maintaining the full biological activity of Vitamin E at a potency level convenient for formulators.
The acetate ester form (all-rac-alpha-tocopheryl acetate) is a critical stability innovation. Free alpha-tocopherol has an exposed phenolic hydroxyl group — the very moiety responsible for its antioxidant activity — which also makes it highly susceptible to atmospheric oxidation during processing and storage. Esterification with acetate caps this hydroxyl, producing an oxidation-stable prodrug. The acetate group is cleaved by intestinal and hepatic esterases after oral administration, releasing the active free tocopherol. This strategy extends shelf life from months to years and enables formulation approaches (high-heat extrusion, long-term ambient storage) impossible with unprotected free tocopherol.
As of mid-2026, global Vitamin E demand is driven by three sectors: animal feed (accounting for approximately 65-70% of total volume), dietary supplements (20-25%), and food fortification/cosmetics (5-10%). China dominates global production of Vitamin E acetate, with key manufacturers concentrated in Zhejiang province. Market dynamics are heavily influenced by intermediate availability (particularly trimethylhydroquinone and isophytol), with periodic supply tightness during environmental inspections. KingWish supplies GB/USP-grade Vitamin E 50% powder supporting supplement manufacturers, feed premix producers, and food fortifiers in over 100 countries.
Quality Specifications
| Potency (Content) | ≥ 50.0% as all-rac-alpha-tocopheryl acetate (HPLC) |
|---|---|
| Loss on Drying | ≤ 5.0% |
| Heavy Metals | ≤ 10 ppm; arsenic ≤ 1 ppm; lead ≤ 2 ppm |
| Particle Size | Typically 90% through 40 mesh (dependent on carrier) |
| Residual Solvents | Compliant with ICH Q3C / GB requirements |
| GMP Status | Manufactured under GMP conditions |
Applications
- Dietary Supplements: Vitamin E capsules and tablets, multivitamin blends, and antioxidant complex formulations
- Animal Feed Premix: Nutritional fortification in poultry, swine, and aquaculture complete feed and premix products
- Food Fortification: Fortified edible oils, margarine, breakfast cereals, and functional snack products
- Pet Food: Antioxidant nutrition in dry and wet pet food formulations for dogs and cats
- Multivitamin Formulations: Ready-to-mix powder blends for comprehensive nutritional supplement products
Sourcing Vitamin E 50%: Key Checks
Documentation
Request CoA with HPLC potency assay (≥50.0%), loss on drying, heavy metals, and particle size distribution. Verify the carrier identity (silicon dioxide, starch, maltodextrin) — different carriers affect blending behavior and compatibility with other ingredients. For feed applications, confirm compliance with feed-grade specifications. DrugBank reference
Red Flags
Potency below 48% (below labeled claim), caking or poor flowability indicating moisture exposure, carrier segregation (uneven oil distribution), rancid odor (oxidation), and CoA without batch-specific HPLC data. Verify that the acetate ester form — not free tocopherol — is supplied if stability is critical.
Packaging & Logistics
Standard: 25 KG/DRUM with PE liner. Store in a cool, dry place (15-25 degrees C), protected from light. Avoid extended exposure to temperatures above 40 degrees C. Shelf life typically 24 months. Custom packaging including smaller drums or cartons available for supplement manufacturers.
Market Context
Vitamin E acetate is one of the highest-volume vitamin APIs globally, driven by animal feed demand (65-70% of total). China dominates production with key manufacturing in Zhejiang province. The market is sensitive to intermediate (trimethylhydroquinone, isophytol) supply dynamics. Price cycles typically run 18-24 months. For feed-grade buyers, contract pricing with quarterly adjustment mechanisms is common.