title: Changes in the lipid composition of powdered infant formulas during long-term storage.
abstract: Changes in the lipid composition of two standard infant formulas induced by 4 years of storage were determined. Lipids were thoroughly analyzed using different gas-liquid and liquid-liquid chromatographic techniques. Oleic acid and linoleic acid, which accounted for almost the total monounsaturated and polyunsaturated fatty acids, respectively, showed slight but significant decreases (P < 0.05) during the 4 years of storage (from 41.52 to 39.83% for oleic acid and from 17.35 to 15.99% for linoleic acid). Total trans fatty acid isomers showed low initial level (0.22% of total fatty acids), and such level remained unchanged during the storage period. Nonvolatile oxidation compounds including oxidized, dimeric, and polymeric triglycerides did not significantly increase during the storage period, although a significant loss of tocopherols was found in the surface oil fraction (10-15%). In general, the results obtained indicate that, although small losses of oleic and linolenic acid as well as tocopherols were found, the 4 year storage period did not lead to relevant changes in the lipid fraction of infant formulas.
authors.affiliation: Instituto del Frío (CSIC), 28040 Madrid, Spain; Instituto de Productos LActeos de Asturias (CSIC), 33300 Villaviciosa, Asturias, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Rodríguez-Alcalá
authors.forename: María C
authors.initials: MC
authors.lastname: García-Martínez
authors.forename: Fatima
authors.initials: F
authors.lastname: Cachón
authors.forename: Susana
authors.initials: S
authors.lastname: Marmesat
authors.forename: Leocadio
authors.initials: L
authors.lastname: Alonso
authors.forename: Gloria
authors.initials: G
authors.lastname: Marquez-Ruiz
authors.forename: Javier
authors.initials: J
authors.lastname: Fontecha
mesh_terms: D005227:Fatty Acids / Q000032:analysis; D005519:Food Preservation; D041943:Infant Formula / Q000737:chemistry*; D008055:Lipids / Q000032:analysis*; D010084:Oxidation-Reduction; D013997:Time Factors; D024505:Tocopherols / Q000032:analysis; D044242:Trans Fatty Acids / Q000032:analysis
chemical_list: D005227:Fatty Acids; D008055:Lipids; D044242:Trans Fatty Acids; D024505:Tocopherols