title: Inhibition of lipid oxidation in cooked beef patties by hydrolyzed potato protein is related to its reducing and radical scavenging ability.
abstract: Protein hydrolysates were prepared by limited alcalase hydrolysis (0.5, 1, and 6 h, corresponding to degrees of hydrolysis of 0.72, 1.9, and 2.3, respectively) of heat-coagulated potato protein. The hydrolysates were characterized for peptide composition, ferric reducing/antioxidant power (FRAP), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical-scavenging activity, and Fe2+- and Cu2+-chelation capacity. Hydrolyzed and intact proteins were formulated (4%, w/w) into beef patties to determine in situ antioxidant efficacy. Thiobarbituric acid-reactive substances (TBARS) and peroxide value (PV) formed in cooked and PVC-packaged patties during storage (4 degrees C, 0-7 days) were analyzed. Hydrolysis increased the protein solubility by 14-19-fold and produced numerous short peptides (< 6 kDa). The FRAP values of the protein sample (23 micromol/g) increased markedly after hydrolysis but were similar between the three hydrolysates (597-643 micromol/g). Similarly, the ABTS radical-scavenging activity also was increased by hydrolysis and was the greatest for the 1-h hydrolysate. Hydrolysis increased the Cu2+-chelation activity but decreased the Fe2+-chelation ability of the protein. The production of PV in patties after 7 days of storage was lowered 44.9% and 74.5% (P < 0.05), and that of TBARS was reduced 40.9% and 50.3% (P < 0.05), by intact and hydrolyzed proteins, respectively.
authors.affiliation: Department of Animal and Food Sciences, University of Kentucky, Lexington, Kentucky 40546, USA.
authors.forename: Lynn L
authors.initials: LL
authors.lastname: Wang
authors.forename: Youling L
authors.initials: YL
authors.lastname: Xiong
mesh_terms: D000818:Animals; D002417:Cattle; D002614:Chelating Agents; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006358:Hot Temperature; D006868:Hydrolysis; D015227:Lipid Peroxidation / Q000187:drug effects*; D008460:Meat / Q000032:analysis*; D010940:Plant Proteins / Q000737:chemistry / Q000494:pharmacology*; D019163:Reducing Agents / Q000494:pharmacology*; D011198:Solanum tuberosum / Q000737:chemistry*; D012995:Solubility; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D002614:Chelating Agents; D016166:Free Radical Scavengers; D010940:Plant Proteins; D019163:Reducing Agents; D017392:Thiobarbituric Acid Reactive Substances