Effects of Paprika Pigments on Oxidation of Linoleic Acid Stored in the Dark or Exposed to Light
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- 作者：Hiroshi Matsufuji ; Makoto Chino ; and Mitsuharu Takeda
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2004
- 出版时间：June 2, 2004
- 年：2004
- 卷：52
- 期：11
- 页码：3601 - 3605
- 全文大小：100K
- 年卷期：v.52,no.11(June 2, 2004)
- ISSN：1520-5118
文摘
We examined the antioxidant effects of paprika pigments on oxidation of linoleic acid and ondecoloration of the sample when stored at 37 
C in the dark or exposed to fluorescent light for 8 hper day. 1H nuclear magnetic resonance with dioxane as an external proton reference was used toestimate the oxidative deterioration of linoleic acid. Oxidation was estimated by observing the ratioof the divinylmethylene proton signal area in linoleic acid vs the proton signal area in dioxane. Theaddition of paprika pigments suppressed the oxidation of linoleic acid during storage in the dark, andthe effect was markedly increased with increasing concentrations (0.02, 0.2, and 2%). When thelinoleic acid with added paprika pigments was exposed to light, only a slight suppression of oxidationwas observed, and the color of the sample disappeared more rapidly than that in the dark. At thetime of decoloration of the sample with added pigments, considerable oxidation of linoleic acidoccurred. As the color change is due to degradation of the pigment, an increase in oxidation at thetime of discoloration is consistent with the pigments functioning as antioxidants. The addition of
-tocopherol to paprika pigments stabilized degradation of the pigments by light. Although the additionof -tocopherol to linoleic acid with added paprika pigments prolonged the decoloration of the sampleunder light, the prevention of oxidation under the light condition was not as effective as for the samplesstored in the dark.Keywords: Paprika; carotenoid; antioxidant; oxidation; decoloration; NMR
C in the dark or exposed to fluorescent light for 8 hper day. 1H nuclear magnetic resonance with dioxane as an external proton reference was used toestimate the oxidative deterioration of linoleic acid. Oxidation was estimated by observing the ratioof the divinylmethylene proton signal area in linoleic acid vs the proton signal area in dioxane. Theaddition of paprika pigments suppressed the oxidation of linoleic acid during storage in the dark, andthe effect was markedly increased with increasing concentrations (0.02, 0.2, and 2%). When thelinoleic acid with added paprika pigments was exposed to light, only a slight suppression of oxidationwas observed, and the color of the sample disappeared more rapidly than that in the dark. At thetime of decoloration of the sample with added pigments, considerable oxidation of linoleic acidoccurred. As the color change is due to degradation of the pigment, an increase in oxidation at thetime of discoloration is consistent with the pigments functioning as antioxidants. The addition of-tocopherol to paprika pigments stabilized degradation of the pigments by light. Although the additionof -tocopherol to linoleic acid with added paprika pigments prolonged the decoloration of the sampleunder light, the prevention of oxidation under the light condition was not as effective as for the samplesstored in the dark.Keywords: Paprika; carotenoid; antioxidant; oxidation; decoloration; NMR