Role of lipid oxidation, chelating agents, and antioxidants in metallic flavor development in the oral cavity.
This study investigated the production of metallic flavor, which is a combination of taste and retronasal odor. Chemical reactions in the oral cavity and saliva of healthy subjects were investigated after ingesting iron and copper solutions above and near threshold levels. Significant increase in lipid oxidation (p < 0.001) occurred after metal ingestion, detected as TBARS values. Ferrous ion caused the greatest flavor sensation and lipid oxidation, followed by cupric and cuprous ions. Ferric ion did not cause metallic sensation. Occurrence of oxidation was supported by damage to salivary proteins, detected as protein-carbonyls, and by a significant increase of odorous lipid oxidation related aldehydes. Sensory evaluation demonstrated that antioxidants (vitamins E and C) minimally reduced metallic flavor but that chelating agents (EDTA and lactoferrin) removed the metallic flavor. The role of lipid oxidation is essential for the production of a metallic flavor from ingestion of ferrous, cupric, and cuprous ions.
Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States.
Pinar
P
Omür-Özbek
Andrea M
AM
Dietrich
Susan E
SE
Duncan
YongWoo
Y
Lee
D000328:Adult; D000975:Antioxidants / Q000494:pharmacology*; D002614:Chelating Agents / Q000494:pharmacology*; D003300:Copper / Q000008:administration & dosage; D005260:Female; D005296:Ferrous Compounds / Q000008:administration & dosage; D006801:Humans; D007501:Iron / Q000008:administration & dosage; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D008670:Metals; D008875:Middle Aged; D009055:Mouth / Q000502:physiology*; D012471:Salivary Proteins and Peptides / Q000037:antagonists & inhibitors; D012996:Solutions; D013649:Taste / Q000502:physiology*
D000975:Antioxidants; D002614:Chelating Agents; D005296:Ferrous Compounds; D008670:Metals; D012471:Salivary Proteins and Peptides; D012996:Solutions; D003300:Copper; D007501:Iron