title: Effects of oxygen and antioxidants on the lipid oxidation and yellow discolouration of film from red tilapia mince.
abstract: BACKGROUND
  Generally, biodegradable films from fish muscle protein become yellow after preparation. This discolouration is more likely associated with lipid oxidation and can be prevented by minimising the oxidation in the films. Thus, the effects of oxygen and antioxidants on lipid oxidation and yellow discolouration of film from red tilapia mince during storage were investigated.
  
  
  RESULTS
  Both films prepared at pH 3 and 11, and kept under atmosphere containing 100% N(2) had the lowest TBARS value with the concomitant lowest b* and ΔE* values during storage (P < 0.05), when compared with other films kept in air and a 100% O(2) atmosphere. Films prepared at pH 3 and incorporated with antioxidants (Trolox and catechin) at all levels (100, 200 and 400 mg L(-1) film-forming solution) had the lowest TBARS value, b* and ΔE* values during storage, indicating the retardation of lipid oxidation and yellow discolouration in films. Nevertheless, films prepared at pH 11 had no difference in TBARS values, in comparison with control film, regardless of antioxidant incorporation. Coincidentally, increases in b* and ΔE* values were observed in those films.
  
  
  CONCLUSIONS
  Lipid oxidation was the main factor inducing yellow discolouration of film exposed to oxygen and the incorporation of antioxidants in film prepared at acidic pH was able to prevent yellow discolouration of resulting film.
authors.affiliation: Department of Food Technology, Faculty of Agro-Industry, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
authors.forename: Phakawat
authors.initials: P
authors.lastname: Tongnuanchan
authors.forename: Soottawat
authors.initials: S
authors.lastname: Benjakul
authors.forename: Thummanoon
authors.initials: T
authors.lastname: Prodpran
mesh_terms: D000388:Air; D000818:Animals; D000975:Antioxidants; D001272:Atmosphere; D002392:Catechin; D002839:Chromans; D003116:Color; D018857:Food Packaging / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D015227:Lipid Peroxidation; D009124:Muscle Proteins; D009584:Nitrogen; D010084:Oxidation-Reduction; D010100:Oxygen; D017392:Thiobarbituric Acid Reactive Substances; D017210:Tilapia
chemical_list: D000975:Antioxidants; D002839:Chromans; D009124:Muscle Proteins; D017392:Thiobarbituric Acid Reactive Substances; D002392:Catechin; D009584:Nitrogen; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D010100:Oxygen