Localized antioxidant degradation

Localized Antioxidant Degradation in Relation to Promotion of Lipid Oxidation... 

In conclusion, monitoring antioxidant degradation in localized areas of tissue can prove useful as a marker for the onset of a product s quality loss. The multifaceted protection available to biological membranes, though, would suggest that measurements of more than one antioxidant are warranted during storage. 

Many oils, particularly those of vegetable origin, are liable to autooxidation with subsequent rancidity, and it is frequently necessary to add an antioxidant and/or preservative to inhibit this degradation process. For externally applied emulsions, mineral oils, either alone or combined with soft or hard paraffins, are widely used both as the vehicle for the drug and for their occlusive and sensory characteristics. The most widely used oils in oral preparations are non-biodegradable mineral and castor oils that provide a local laxative effect, and fish liver oils or various fixed oils of vegetable origin (e.g., arachis, cottonseed, and maize oils) as nutritional supplements. 

Lipid oxidation has been proposed as the vehicle for manifestation of injury and loss of quality in food by physiological stresses such as chilling injury, senescence and dehydration. The objective of this chapter is to review how localized degradation of antioxidants has been used as a marker for early detection of lipid oxidation as well as in defining the mechanism of oxidative challenge. 

Many emulsified lipids and encapsulated BLI are vulnerable to chemical destruction most commonly via oxidative reactions or acid hydrolysis. The structure of the emulsion and the microlocalization of the BLI affect the rate of chemical degradation. It is also important to consider the relative localization of any other reagents (e.g., oxygen, protons), catalysts (e.g., transition metals), and inhibitors of oxidation reactions (e.g., antioxidants) involved in the BLI degradation reaction. 

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