18 Nutraceutical and Pharmaceutical Applications of Carotenoids
459
(1) Dried ground powder: farm animal and fish feeds, foods, and extract materials
for carotenoids
(2) Oil suspension (oreolesin): supplements (soft capsule) and cosmetics
(3) Liquid or dried emulsion formulation: food and beverage colorings and
cosmetics.
(4) Beadlet formulation: foods and supplements (tablet).
18.2.3 Processing
Carotenoids can be obtained from plants, algae, and bacteria, or can be produced
by chemical synthesis. Generally, carotenoids are present in the all-E-configuration
that has high hydrophobicity and high crystallinity. These properties limit their use
for food and cosmetic industries, and thus many commercially available carotenoid
products are subjected to the emulsification and micronization treatments. However,
the efficiencies of carotenoid processings such as extraction, emulsification, and
micronization are very low due to their properties of high hydrophobicity and
high crystallinity, and that results in price increase and quality deterioration of the
carotenoid products. Therefore, many studies have been carried out to improve the
carotenoids processing efficiency. For example, as for carotenoids extraction, extraction conditions (type of solvent, temperature, and time) and extraction apparatus are
well studied, and as for the emulsification, type of emulsifier as well as emulsification
conditions and apparatus are well documented. In recent years, carotenoid processing
utilizing a green solvent, supercritical CO 2 (SC-CO 2 ), which is non-toxic and easily
separated from the products, has been extensively examined. However, there are few
practical examples for carotenoid processing because most carotenoids are very low
solubility in SC-CO 2 . Very recently, it was revealed that Z-isomers of carotenoids
were higher solubility in solvents including SC-CO 2 and lower crystallinity than the
all-E-isomers (Honda et al. 2018a; Murakami et al. 2017). By utilizing the change
in the physicochemical properties via the Z-isomerization, several studies successfully improved the efficiency of carotenoid processing using SC-CO 2 . For example,
Honda et al. (2017b, 2018b) demonstrated that the thermal Z-isomerization pretreatment to tomato pulp and gac (Momordica cochinchinensis Spreng.) markedly
improved the SC-CO 2 extraction efficiency of lycopene. Moreover, when Z-isomerrich carotenoids were used as the raw material for emulsification and micronization
processings using SC-CO 2 as a mediator, those efficiencies were notably improved
compared with using the all-E-isomers (Kodama et al. 2018; Ono et al. 2018), e.g.,
in emulsification of β-carotene using SC-CO 2 as the organic phase, the encapsulated
efficiency of β-carotene Z-isomers was 21.2 times higher than that of the all-Eisomer (Ono et al. 2018). For the sustainable development of carotenoid products in
the future, further development of carotenoids processing with SC-CO 2 is expected
and utilizing the change in the physicochemical properties of carotenoids by the
Z-isomerization may be breakthrough of that realization.
459
(1) Dried ground powder: farm animal and fish feeds, foods, and extract materials
for carotenoids
(2) Oil suspension (oreolesin): supplements (soft capsule) and cosmetics
(3) Liquid or dried emulsion formulation: food and beverage colorings and
cosmetics.
(4) Beadlet formulation: foods and supplements (tablet).
18.2.3 Processing
Carotenoids can be obtained from plants, algae, and bacteria, or can be produced
by chemical synthesis. Generally, carotenoids are present in the all-E-configuration
that has high hydrophobicity and high crystallinity. These properties limit their use
for food and cosmetic industries, and thus many commercially available carotenoid
products are subjected to the emulsification and micronization treatments. However,
the efficiencies of carotenoid processings such as extraction, emulsification, and
micronization are very low due to their properties of high hydrophobicity and
high crystallinity, and that results in price increase and quality deterioration of the
carotenoid products. Therefore, many studies have been carried out to improve the
carotenoids processing efficiency. For example, as for carotenoids extraction, extraction conditions (type of solvent, temperature, and time) and extraction apparatus are
well studied, and as for the emulsification, type of emulsifier as well as emulsification
conditions and apparatus are well documented. In recent years, carotenoid processing
utilizing a green solvent, supercritical CO 2 (SC-CO 2 ), which is non-toxic and easily
separated from the products, has been extensively examined. However, there are few
practical examples for carotenoid processing because most carotenoids are very low
solubility in SC-CO 2 . Very recently, it was revealed that Z-isomers of carotenoids
were higher solubility in solvents including SC-CO 2 and lower crystallinity than the
all-E-isomers (Honda et al. 2018a; Murakami et al. 2017). By utilizing the change
in the physicochemical properties via the Z-isomerization, several studies successfully improved the efficiency of carotenoid processing using SC-CO 2 . For example,
Honda et al. (2017b, 2018b) demonstrated that the thermal Z-isomerization pretreatment to tomato pulp and gac (Momordica cochinchinensis Spreng.) markedly
improved the SC-CO 2 extraction efficiency of lycopene. Moreover, when Z-isomerrich carotenoids were used as the raw material for emulsification and micronization
processings using SC-CO 2 as a mediator, those efficiencies were notably improved
compared with using the all-E-isomers (Kodama et al. 2018; Ono et al. 2018), e.g.,
in emulsification of β-carotene using SC-CO 2 as the organic phase, the encapsulated
efficiency of β-carotene Z-isomers was 21.2 times higher than that of the all-Eisomer (Ono et al. 2018). For the sustainable development of carotenoid products in
the future, further development of carotenoids processing with SC-CO 2 is expected
and utilizing the change in the physicochemical properties of carotenoids by the
Z-isomerization may be breakthrough of that realization.