Difference between revisions of "Vitamin A"
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<br /> Figure 1. All-''trans''-retinol, C<sub>20</sub>H<sub>30</sub>O, Mw =286,45 g/mol. | <br /> Figure 1. All-''trans''-retinol, C<sub>20</sub>H<sub>30</sub>O, Mw =286,45 g/mol. | ||
| − | The group of vitamin A includes retinol, its esters and some isomers. Vitamin A substances from animal sources are called retinoids and these include all-trans-retinol, retinylesters and cis-isomers. Carotenoids (provitamin A) are present in plants, such as fruits and vegetables, and this group includes | + | The group of vitamin A includes retinol, its esters and some isomers. Vitamin A substances from animal sources are called retinoids and these include all-trans-retinol, retinylesters and cis-isomers. Carotenoids (provitamin A) are present in plants, such as fruits and vegetables, and this group includes β-carotene, α-carotene, γ-carotene and β-cryptoxanthin. |
Synonyms for vitamin A: | Synonyms for vitamin A: | ||
Latest revision as of 13:33, 9 May 2019
Figure 1. All-trans-retinol, C20H30O, Mw =286,45 g/mol.
The group of vitamin A includes retinol, its esters and some isomers. Vitamin A substances from animal sources are called retinoids and these include all-trans-retinol, retinylesters and cis-isomers. Carotenoids (provitamin A) are present in plants, such as fruits and vegetables, and this group includes β-carotene, α-carotene, γ-carotene and β-cryptoxanthin.
Synonyms for vitamin A:
- retinol, axerophthol, vitamin A1.
Summary - measurement of all-trans-retinol and 13-cis-retinol
Summary - measurement of beta-carotene
Contents
Golden standard
There are two European Standards concerning the determination of vitamin A. Methods are described in child pages where you can get by clicking the links below:
Proficiency testing schemes
Here are listed some completed, on-going and/or upcoming proficiency testing schemes concerning vitamin A:
Livsmedelsverket, National Food Agency of Sweden - Report 24 (2011) Vitamins in Foods - Round V-9
DRRR - Deutsches Referenzbüro für Lebensmittel-Ringversuche und Referenzmaterialien
LGC - Dairy Chemistry PT schemes (QDCS)
Some upcoming proficiency testing schemes can be found in the EPTIS database.
Other methods available
- AACC 86-01.02 Vitamin A---Ultraviolet Absorption Method
- AACC 86-02.01 Vitamin A---Carr-Price Method
- AACC 86-03.01 Vitamin A in Enriched Flour
- AACC 86-05.01 Vitamin A and Carotene
- AACC 86-06.01 Analysis of Vitamins A and E by High-Performance Liquid Chromatography
- AOAC 960.45 Vitamin A in margarine
- spectrophotometric
- AOAC 974.29 Vitamin A in mixed feed, premixes, and human and pet foods (Codex adopted - AOAC Method)
- colorimetric
- AOAC 992.04 Vitamin A (retinol isomers) in milk and milk-based infant formula (Codex adopted - AOAC Method)
- liquid chromatographic
- AOAC 992.06 Vitamin A (retinol) in milk-based infant formula (Codex adopted - AOAC Method)
- liquid chromatographic
- AOAC 2001.13 Determination of vitamin A in foods
- liquid chromatographic
- ISO 12080-1:2009 Dried skimmed milk - Determination of vitamin A content -- part 1: Colorimetric method
- ISO 12080-2:2009 Dried skimmed milk - Determination of vitamin A content -- part 2: Method using high performance liquid chromatography
- ISO 6558-2:1992 Fruits, vegetables and derived products -- Determination of carotene content -- Part 2: Routine methods
Literature
- see separate child page below
