title: Impact of iron, chelators, and free fatty acids on lipid oxidation in low-moisture crackers.
abstract: This research strove to understand the relationship between physical structure and oxidative stability in crackers since mechanisms of lipid oxidation are poorly understood in low-moisture foods. Confocal microscopy showed that lipids formed a continuous matrix surrounding starch granules, and starch-lipid, lipid-air, and protein-lipid interfaces were observed. Unlike bulk oils, meats, and emulsions, lipid hydroperoxides exhibited greater stability in low-moisture crackers as hexanal formation was delayed >20 d. Iron, added at 10 times the concentrations normally found in enriched flour, did not increase oxidation rates compared to the control. EDTA may reduce endogenous iron activity but not as greatly as in other matrices. Addition of fatty acids up to 1.0% of total lipid weight did not statistically affect lipid oxidation lag phases. The unique structure of low-moisture foods clearly affects their resistance to metal-promoted lipid oxidation.
authors: Department of Food Science, University of Massachusetts Amherst , 102 Holdsworth Way, Amherst, Massachusetts 01003, United States.
authors: Leann
authors: L
authors: Barden
authors: Daniel
authors: D
authors: Vollmer
authors: David
authors: D
authors: Johnson
authors: Eric
authors: E
authors: Decker
mesh_terms: D004042:Dietary Fats, Unsaturated / Q000032:analysis; D002523:Edible Grain / Q000737:chemistry*; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D005456:Fluorescent Dyes; D007501:Iron / Q000494:pharmacology*; D007502:Iron Chelating Agents / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects*; D018613:Microscopy, Confocal; D010084:Oxidation-Reduction; D014867:Water / Q000032:analysis*
chemical_list: D004042:Dietary Fats, Unsaturated; D005230:Fatty Acids, Nonesterified; D005456:Fluorescent Dyes; D007502:Iron Chelating Agents; D014867:Water; D007501:Iron
keywords: antioxidants; confocal microscopy; crackers; free fatty acid; iron; lipid oxidation; low-moisture foods; prooxidant metals