Analysis of vitamins in food
Vitamin analysis is carried out either microbiologically using the VitaFast® kits specially developed by ifp or by means of instrumental analysis (high performance liquid chromatography, HPLC).
Determination using VitaFast® and HPLC
Analysis of all water-soluble vitamins (except for vitamin C) is done with the VitaFast® kits developed and produced by ifp. These kits are an innovative advancement of the official method which has been the gold standard in the analysis of water-soluble vitamins for decades. The method uses microorganisms, the growth of which depends on the presence of the vitamin in the sample, in order to detect and quantify the vitamin of interest. This method is traditionally associated with a great deal of work and requires a high level of microbiological expertise. The average turnaround time is one week or more.
With VitaFast®, ifp successfully transferred the official method into a ready-to-use microtiter plate format. Results are usually available after just 48 hours.
The determination of vitamin C (ascorbic acid) in food is carried out using a microtiter plate-based enzymatic assay. Unlike the conventional method, this format no longer requires single measurements in cuvettes, thus allowing for much more efficient sample processing.
The ifp was also able to expand its capabilities in the area of determination by means of high-performance liquid chromatography (HPLC). In addition to fat-soluble vitamins A, D, E, and K as well as vitamin C, the B-vitamins thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin and folic acid can also be determined by HPLC. Furthermore, analyses of carnitine, choline, taurine and free inositol are possible. The detection is performed by fluorescence detector (FLD), a UV detector with diode array (DAD) or by coupling with tandem mass spectrometry (MS/MS).
Quantification limits using VitaFast®and enzymology
|
Compound |
Limit of quantification per 100 g/ml |
|
B1 (thiamine) |
0,012 mg |
|
B2 (riboflavin) |
0,04 mg |
|
B3 (niacin) |
0,016 mg |
|
B5 (pantothenic acid) |
0,04 mg |
|
B6 (pyridoxine) |
0,002 mg |
|
B7 (biotin) |
0,08 µg |
|
B9 (folic acid) |
0,16 µg |
|
B12 (cyanocobalamin) |
0,03 µg |
|
C (ascorbic acid) |
10 mg |
|
Inositol |
0,5 mg |
Quantification limits using HPLC
|
Compound |
Limit of quantification per 100 g/ml |
|
A (retinol; precursor: β-Carotin) |
4,0 µg |
|
D2/D3 (ergocalciferol/cholecalciferol) |
0,3 µg |
|
E (α-1), β-, δ-, ε-tocopherol) |
0,2 mg |
|
K1/K2 (phylloquinone/menaquinone2)) |
2,0 µg |
|
C (ascorbic acid) |
0,5 mg |
|
B1 (thiamine) |
0,08 mg |
|
B2 (riboflavin) |
0,08 mg |
|
B3 (niacinamid)3) |
0,8 mg |
|
B3 (nicotinic acid)3) |
0,5 mg |
|
B5 (pantothenic acid)3) |
1,1 mg |
|
B6 (pyridoxine) |
0,08 mg |
|
B7 (biotin)3) |
1,6 µg |
|
B9 (5-methyltetrahydrofolic acid – natural form)3) |
5 µg |
| B9 (folic acid – synthetic form) 3) | 5 µg |
| taurine3) | 2,0 mg |
| Free L-carnitine3) | 0,5 mg |
| Total carnitine3) | 1 mg |
| Total choline3) | 3 mg |
| Free inositol3) | 5,0 mg |
1) Enantiomer separation of D-α- and L-α-tocopherol is possible
2) Differentiation into MK-4 and MK-7 is possible
3) Determination by means of LC-MS/MS
Please ask in advance for which matrices our respective methods are validated.