title: Antioxidant capacity of fresh and stored breast milk: is -80°C optimal temperature for freeze storage?
abstract: OBJECTIVE
  To determine total antioxidant capacity and total oxidation status in fresh and freeze stored (at -80°C) breast milk during the stages of lactation.
  
  
  METHODS
  Samples of colostrum, transitional and mature milk were collected from 44 healthy women at 3, 8 and 30 days after birth. The total milk volume collected (6 ml) was divided in two aliquot parts: 3 ml for the fresh analysis which was done immediately after the extraction and 3 ml for storage under freezing conditions at -80°C for two months. The antioxidant status and oxidative stress of the fresh and stored breast milk were assessed via determination of total antioxidant capacity and total oxidation status.
  
  
  RESULTS
  Antioxidant capacity of transitional and mature milk decreased (p = 0.0001, p = 0.028, respectively); however, antioxidant capacity of colostrum did not change by storage at -80°C (p > 0.05). Total antioxidant capacity of fresh and stored breast milk significantly decreased during the stages of lactation (p < 0.0001, p = 0.028, respectively). Total oxidation status showed no significant difference in fresh and stored breast milk during the stages of lactation (p > 0.05).
  
  
  CONCLUSIONS
  Freeze storage of breast milk at -80°C for two months seems not to be the optimal condition to preserve the antioxidant capacity of breast milk.
authors.affiliation: Neonatal Intensive Care Unit, Zekai Tahir Burak Maternity Teaching Hospital, Altindag-Ankara, Turkey. fatmanurselek@yahoo.com
authors.forename: Fatma Nur
authors.initials: FN
authors.lastname: Sari
authors.forename: Arzu
authors.initials: A
authors.lastname: Akdag
authors.forename: Evrim Alyamac
authors.initials: EA
authors.lastname: Dizdar
authors.forename: Nurdan
authors.initials: N
authors.lastname: Uras
authors.forename: Omer
authors.initials: O
authors.lastname: Erdeve
authors.forename: Ozcan
authors.initials: O
authors.lastname: Erel
authors.forename: Ugur
authors.initials: U
authors.lastname: Dilmen
mesh_terms: D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000032:analysis*; D003080:Cold Temperature; D003126:Colostrum / Q000737:chemistry; D004034:Diet Surveys; D005260:Female; D061353:Food Storage / Q000379:methods*; D005615:Freezing; D006801:Humans; D039382:Maternal Nutritional Physiological Phenomena; D008895:Milk, Human / Q000737:chemistry*; D011247:Pregnancy; D011309:Preservation, Biological / Q000379:methods; D013048:Specimen Handling / Q000379:methods; D055815:Young Adult
chemical_list: D000975:Antioxidants