Fat-soluble vitamins A, D, E, and K are essential micronutrients absorbed with dietary fats and stored in fatty tissues. Their accurate determination is critical for nutritional labeling, fortification verification, and supplement quality control. Ovalab offers comprehensive fat-soluble vitamin testing.
Key Facts About Fat-Soluble Vitamins (A, D, E, K)
- EU NRVs (Annex XIII, Regulation 1169/2011): Vitamin A 800 µg, Vitamin D 5 µg, Vitamin E 12 mg, Vitamin K 75 µg.
- Method: Simultaneous HPLC-DAD (diode array detection) determines all four vitamins in a single chromatographic run.
- Sample preparation: Saponification, liquid-liquid extraction, and purification before HPLC analysis.
- Vitamin forms: A as retinol/retinyl esters; D as D2 and D3; E as α-tocopherol; K as phylloquinone (K1) and menaquinones (K2).
- Claims: “Source of” requires ≥ 15% NRV per 100 g; “high in” requires ≥ 30% NRV (Regulation 1924/2006).
Testing Methods at Ovalab
Ovalab determines fat-soluble vitamins using HPLC-DAD and LC-MS/MS for simultaneous quantification. Sample preparation involves saponification and solvent extraction optimized per matrix. Under ISO/IEC 17025:2018 (ČIA, Certificate 537/2025) and GMP (SÚKL 74726/2023).
Frequently Asked Questions
Can all four fat-soluble vitamins be tested simultaneously?
Yes. Ovalab uses HPLC-DAD methods to determine vitamins A, D, E, and K in a single run after saponification and extraction — efficient and cost-effective.
What are the EU NRVs for fat-soluble vitamins?
Per Annex XIII, Regulation 1169/2011: Vitamin A 800 µg, Vitamin D 5 µg, Vitamin E 12 mg, Vitamin K 75 µg.
Why is saponification needed?
Saponification (alkaline hydrolysis with KOH) breaks the fat matrix and releases vitamins from ester forms, essential for extraction from dairy, oils, and fortified foods.
Which products require fat-soluble vitamin testing?
Fortified dairy/plant milks, margarines, infant formulas, cooking oils, supplements, fish oils, egg products, and liver products.
How does Ovalab ensure accuracy for vitamin D at low levels?
For vitamin D at low concentrations, Ovalab uses LC-MS/MS for superior sensitivity vs. HPLC-DAD — critical for non-fortified foods with naturally low vitamin D.