Changes in the lipid composition of powdered infant formulas during long-term storage.
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.
Rodríguez-Alcalá
Luis M
LM
Instituto del Frío (CSIC), 28040 Madrid, Spain; Instituto de Productos LActeos de Asturias (CSIC), 33300 Villaviciosa, Asturias, Spain.
García-Martínez
María C
MC
Cachón
Fatima
F
Marmesat
Susana
S
Alonso
Leocadio
L
Marquez-Ruiz
Gloria
G
Fontecha
Javier
J
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
D005227:Fatty Acids; D008055:Lipids; D044242:Trans Fatty Acids; D024505:Tocopherols