Effects of Fatty Acid Composition and β‐Carotene on the Chlorophyll Photosensitized Oxidation of W/O Emulsion Affected by Phosphatidylcholine

Abstract

The results of this study can be applied to the area of emulsion foods such as salad dressing to have improved texture and stability by decreasing the oil oxidation and providing desirable color by use of β-carotene with phosphatidylcholine as emulsifier.

Effects of Phosphatidylcholine on Interaction of α‐Tocopherol and β‐Carotene in Photosensitized Oxidation of Emulsions

“…The CDA values of oil in the emulsion also significantly decreased by addition of a-tocopherol (500 mg/kg) or b-carotene (10 mg/kg). These results confirmed the antioxidant activities of a-tocopherol and b-carotene in chlorophyll-photosensitized oxidation of sunflower oil emulsion, and this could be due to physical and chemical quenching of singlet oxygen as shown in our previous studies [3,8]. Chemical quenching of singlet oxygen can produce peroxides which contribute to the POV increase [4].…”

“…Distilled water (50 g) was slowly added to the mixture, followed by homogenization using an Ultra-Turrax T25 homogenizer equipped with an S25 N-25F dispersing tool (IKA Instruments, Staufen, Germany). Concentrations of chlorophyll b, PC, a-tocopherol, and b-carotene were 4, 250, 500, and 10 mg/kg of emulsion, which previously had shown significant effects on chlorophyll-photosensitized oxidation in an emulsion with the same composition [3,8]. The control sample was given only chlorophyll b without any PC, a-tocopherol, or b-carotene; however, there was no phase separation throughout 24 h just as other samples, mainly due to xanthan gum.…”

“…Analyses of Chlorophyll, a-Tocopherol, b-Carotene, and PC Chlorophyll b, a-tocopherol, b-carotene, and PC, which were added for emulsion preparation, were monitored in each phase (oil, interfacial, and water layer) during the emulsion oxidation by HPLC and thin-layer chromatography (TLC) [3,8]. Chlorophyll b content was determined by HPLC.…”

“…Carotenoids show relatively high reduction potential compared to that of lipid radicals, and thus their scavenging on lipid radicals is not easy [4]. Although tocopherols and carotenoids interactively increased the antioxidant activity in auto-and photosensitized oxidation of bulk oil [6,7], a-tocopherol-PC or b-carotene-PC showed simple addition and antagonism, respectively, in the oil oxidation in an emulsion system [3,8].…”

“…Most reports on the interactions among antioxidants have focused on the autoxidation of oil [9][10][11], and there were very few reports on the interaction between phospholipids and b-carotene [8] or between phospholipids and a-tocopherol [3] on photooxidation so far. There has been no study reported on the interaction among phospholipids, a-tocopherol, and b-carotene in an emulsion.…”