Momordica cochinchinensis, so-called gaˆ´ c in Vietnam, is considered as a fruit with high nutritional potential. Its
antioxidant property, due to a high concentration of carotenes (β-carotene and lycopene), is particularly
estimated. In this study, we have investigated the degradation of carotene extracts obtained from gaˆ´ c aril.
These extracts were dispersed in the aqueous phase in Tween 80 micelles or were encapsulated into polylactic
acid (PLA) particles. In both cases, carotenes were far less degraded than synthetic β-carotene. However, the
degradation of lycopene was still rapid (around 1 mM lycopene degraded per hour), whereas β-carotene was
almost not bleached. Moreover, in gaˆ´ c, the cleavage of the β-carotene's molecule was situated nearer the
extremity of the cycle than for pure β-carotene. It gave rise essentially to β-cyclocitral. For encapsulated β-
carotene, the presence of PLA modified this site to the C9-10 bond which is the favoured cleavage site of pure
β-carotene.
We conclude that the presence of lycopene in gaˆ´ c has a protective role on the molecule of β-carotene and
modifies the cleavage site. However, the supramolecular structure is still very important in the orientation of
cleavage as the encapsulation in PLA particles increases degradation and modifies the cleavage site.