title: Stability improvement of natural food colors: Impact of amino acid and peptide addition on anthocyanin stability in model beverages.
abstract: Anthocyanins are prone to chemical degradation and color fading in the presence of vitamin C. The potential of three amino acids (l-phenylalanine, l-tyrosine, l-tryptophan) and a polypeptide (ε-poly-l-lysine) in prolonging the color stability of purple carrot anthocyanins (0.025%) in model beverages (0.05% l-ascorbic acid, citric acid, pH 3.0) stored at elevated temperature (40°C/7 days) was examined. In the absence of amino acids or peptides, anthocyanin degraded at first-order reaction rate. Addition of amino acids or peptide (0.1%) increased the color stability of anthocyanins, with the most significant improvement observed for l-tryptophan. The average half-life of anthocyanin color increased from 2 days to 6 days with l-tryptophan addition. Fluorescence quenching measurements revealed that the l-tryptophan interacted with anthocyanins mainly through hydrogen bonding, although some hydrophobic interaction may also have been involved. Overall, this study suggests that amino acid or peptide addition may prolong the color stability of anthocyanin in beverage products.
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Chung
authors.affiliation: PepsiCo Global R&D, 100 Stevens Ave, Valhalla, NY 10595, USA.
authors.forename: Thananunt
authors.initials: T
authors.lastname: Rojanasasithara
authors.affiliation: PepsiCo Global R&D, 100 Stevens Ave, Valhalla, NY 10595, USA.
authors.forename: William
authors.initials: W
authors.lastname: Mutilangi
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA; Department of Biochemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 Saudi Arabia. Electronic address: mcclements@foodsci.umass.edu.
authors.forename: David Julian
authors.initials: DJ
authors.lastname: McClements
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000872:Anthocyanins / Q000737:chemistry*; D001205:Ascorbic Acid / Q000737:chemistry; D019343:Citric Acid / Q000737:chemistry; D003116:Color; D018552:Daucus carota / Q000737:chemistry; D005505:Food Coloring Agents / Q000737:chemistry*; D000067030:Fruit and Vegetable Juices / Q000032:analysis*; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D010455:Peptides / Q000737:chemistry*; D010649:Phenylalanine / Q000737:chemistry; D011107:Polylysine / Q000737:chemistry; D014364:Tryptophan / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry
chemical_list: D000596:Amino Acids; D000872:Anthocyanins; D005505:Food Coloring Agents; D010455:Peptides; D011107:Polylysine; D019343:Citric Acid; D014443:Tyrosine; D010649:Phenylalanine; D014364:Tryptophan; D001205:Ascorbic Acid
keywords: Anthocyanin; Beverage system; Color stability; Peptides; Tryptophan