Photoprotection of Vitamins in Skimmed Milk by an Aqueous Soluble Lycopene−Gum Arabic Microcapsule

Abstract

Riboflavin (Rf)-mediated photosensitized degradation of vitamins A and D3 in skimmed milk under illumination with a white fluorescence lamp was studied by using the HPLC technique. The photosensitized degradation of both vitamins followed first-order kinetics, and the temperature effect on the observed photodegradation rate constant allowed the determination of the activation energy Ea as being 4 and 16 kcal/mol for vitamins A and D3, respectively. The addition of lycopene microencapsulated by spray-drying with a gum arabic-sucrose (8:2) mixture (MIC) produced a reduction of ca. 45% in the photosensitized degradation rate of both vitamins. Front-face fluorescence experiments showed the same photoprotection factor in the degradation of Rf itself, indicating that the photodegradation mechanism involved Rf-mediated reactive species, such as the excited triplet state of Rf, 3Rf*, and/or singlet molecular oxygen, 1O2. The interaction of both 3Rf* and 1O2 with MIC was evaluated in aqueous solutions by using laser-induced time-resolved absorption or emission spectroscopy, and the contribution of an inner-filter effect in the presence of MIC in skimmed milk was evaluated by diffuse reflectance spectroscopy. The main operating mechanism of photoprotection is due to the deactivation of 3Rf* by the proteic component of gum arabic; thus, gum arabic based microcapsules could be used to improve the photostability of milk during its storage and/or processing under light.

Development of lycopene-loaded lipid-core nanocapsules: physicochemical characterization and stability study

“…The high encapsulation efficiency indicates that the majority of the Lyc in the suspension was present in the nanocapsule structures. Montenegro et al (2007) obtained Lyc microcapsules in gum arabic with 95 % encapsulation efficiency, and Silva et al (2012) obtained Lyc microcapsules in a gelatinpectin complex with 93.2 % encapsulation efficiency. However, the encapsulants chosen, such as gelatin, gum arabic, gellan gum, and maltodextrin, can affect the encapsulation efficiency Rodriguez-Huezo et al 2004;Shu et al 2006).…”

“…As an antioxidant, Lyc has a singlet-oxygen-quenching ability that is twice that of b-carotene and 10 times higher than that of atocopherol (Silva et al 2012). However, some studies have shown that encapsulation techniques increase the stability of Lyc in the presence of oxygen, heat, and light (Chiu et al 2007; Goula and Adamopoulos 2012;Montenegro et al 2007;Blanch et al 2007).…”

Gum Arabic: More Than an Edible Emulsifier

“…In addition, Montenegro et al, (2007) determined that the photosensitized RF-mediated degradation of vitamins A, D 3 , and RF itself in skimmed milk was strongly reduced by the addition of small amounts of lycopene-gum arabic-sucrose microcapsules, prepared by spray-drying. Under these conditions, the bulk properties of the skimmed milk were unmodified.…”

Characterization of different annatto extracts based on antioxidant and colour properties

“…In addition, carotenoids are also able to quench the excited triplet state of sensitizers, which are relevant species in the oxidation of lipids, vitamins and proteins (Montenegro, Nunes, Mercadante, & Borsarelli, 2007;Montenegro et al, 2004). Carotenoids also act as scavengers of free radicals (Bohm, Puspitasari-Nienaber, Ferruzzi, & Schwartz, 2002;Miller, Sampson, Candeias, Bramley, & Rice-Evans, 1996;Re et al, 1999).…”