Investigating carotenoid loss after drying and storage of

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1. Literature review
A activity (Rodriguez-Amaya 1997; Tanumihardjo 2002). β-carotene is the carotenoid
with the highest provitamin A activity (100%) because the β-carotene molecule can be
entirely converted into two molecules of vitamin A or retinol (Figure 1-11; Table 1-3).
Figure 1-11: Structures of the most common provitamin A carotenoids and retinol.
National Academy of Sciences/Institute of Medicine (2001).
Table 1-3: Relatives bioactivities (%) of some provitamins A compounds in
comparison with trans-β-carotene as reported by Bauernfeind (1972); Zechmeister
(1949) and summarised by Rodriguez-Amaya (1997).
Provitamin A Bauernfeind (1972) Zechmeister (1949)
trans-β-carotene 100 100
13-cis-β-carotene - 53
9-cis-β-carotene - 38
trans-#-carotene 50-54 53
cis-#-carotene (13-cis?) - 16
cis-#-carotene (9-cis?) - 13
trans-5-6-monoepoxy-β-carotene 21 -
trans-γ-carotene 42-50 42
cis-γ-carotene - 19
trans-β-cryptoxanthin 50-60 57
cis-β-cryptoxanthin (9-cis?) - 27
cis-β-cryptoxanthin (15-cis?) - 42
trans-β-apo-8-carotenal 72 -
trans-β-zeacarotene 20-40 -
trans-mutachrome 50 -
About 50 carotenoids are known to have a provitamin A activity (Lee et al. 1989). Of
these compounds, provitamin A carotenes most commonly encountered include β-