title: Increasing the cooking temperature of meat does not affect nonheme iron absorption from a phytate-rich meal in women.
abstract: The effect of increasing cooking temperatures of meat on nonheme iron absorption from a composite meal was investigated. Cysteine-containing peptides may have a role in the iron absorption enhancing effect of muscle proteins. Heat treatment can change the content of sulfhydryl groups produced from cysteine and thereby affect iron absorption. Twenty-one women (25 +/- 3 y) were served a basic meal without meat and two other meals consisting of the basic meal plus 75 g of pork meat cooked at 70, 95 or 120 degrees C. The meals were extrinsically labeled with (55)Fe or (59)Fe. Iron absorption was determined from measurements of whole-body (59)Fe retention and the activity of (55)Fe and (59)Fe in blood samples. Nonheme iron absorptions were 0.9 (0.5-4.0)% (P = 0.06), 0.7 (0.4-3.9)% (P = 0.1) and 2.0 (1.3-3.1)% (P < 0.001) greater when meat cooked at 70, 95 or 120 degrees C, respectively, was added to the basic meal. Increasing the cooking temperature of meat did not impair nonheme iron absorption compared with cooking at 70 degrees C. Because the cysteine content of meat decreased with increasing cooking temperature, this argues against a specific contribution of sulfhydryl groups from cysteine residues in the promotion of nonheme iron absorption by meat proteins.
authors.affiliation: LMC Center for Advanced Food Studies/Department of Human Nutrition, The Royal Veterinary and Agricultural University, DK-1958 Frederiksberg, Denmark.
authors.forename: Sussi B
authors.initials: SB
authors.lastname: Baech
authors.forename: Marianne
authors.initials: M
authors.lastname: Hansen
authors.forename: Klaus
authors.initials: K
authors.lastname: Bukhave
authors.forename: Lars
authors.initials: L
authors.lastname: Kristensen
authors.forename: Mikael
authors.initials: M
authors.lastname: Jensen
authors.forename: Sven S
authors.initials: SS
authors.lastname: Sørensen
authors.forename: Peter P
authors.initials: PP
authors.lastname: Purslow
authors.forename: Leif H
authors.initials: LH
authors.lastname: Skibsted
authors.forename: Brittmarie
authors.initials: B
authors.lastname: Sandström
mesh_terms: D000328:Adult; D000818:Animals; D001682:Biological Availability; D003296:Cooking; D005260:Female; D006801:Humans; D007408:Intestinal Absorption; D019266:Iron, Dietary / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D008460:Meat; D009752:Nutritional Status; D010833:Phytic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D013552:Swine
chemical_list: D019266:Iron, Dietary; D010833:Phytic Acid