title: Correlating enzymatic browning inhibition and antioxidant ability of Maillard reaction products derived from different amino acids.
abstract: BACKGROUND
  Up to now, only limited research on enzymatic browning inhibition capacity (BIC) of Maillard reaction products (MRPs) has been reported and there are still no overall and systematic researches on MRPs derived from different amino acids. In the present study, BIC and antioxidant capacity, including 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and Fe2+reducing power activity, of the MRPs derived from 12 different amino acids and three reducing sugars were investigated.
  
  
  RESULTS
  The MRPs of cysteine (Cys), cystine, arginine (Arg) and histidine (His) showed higher BIC compared to other amino acids. Lysine (Lys)-MRPs showed the highest absorbance value at 420 nm (A420) but very limited BIC, whereas Cys-MRPs, showed the highest BIC and the lowest A420. The A420can roughly reflect the trend of BIC of MRPs from different amino acids, except Cys and Lys. MRPs from tyrosine (Tyr) showed the most potent antioxidant capacity but very limited BIC, whereas Cys-MRPs showed both higher antioxidant capacity and BIC compared to other amino acids. Partial least squares regression analysis showed positive and significant correlation between BIC and Fe2+reducing power of MRPs from 12 amino acids with glucose or fructose, except Lys, Cys and Tyr. The suitable pH for generating efficient browning inhibition compounds varies depending on different amino acids: acidic pH was favorable for Cys, whereas neutral and alkaline pH were suitable for His and Arg, respectively. Increasing both heating temperature and time over a certain range could improve the BIC of MRPs of Cys, His and Arg, whereas any further increase deteriorates their browning inhibition efficiencies.
  
  
  CONCLUSIONS
  The types of amino acid, initial pH, temperature and time of the Maillard reaction were found to greatly influence the BIC and antioxidant capacity of the resulting MRPs. There is no clear relationship between BIC and the antioxidant capacity of MRPs when reactant type and processing parameters of the Maillard reaction are considered as variables. © 2017 Society of Chemical Industry.
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, PR China.
authors.forename: Haining
authors.initials: H
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, PR China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, PR China.
authors.forename: Eric
authors.initials: E
authors.lastname: Karangwa
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, PR China.
authors.forename: Shuqin
authors.initials: S
authors.lastname: Xia
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry*; D005632:Fructose / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D017127:Glycation End Products, Advanced / Q000737:chemistry*; D006358:Hot Temperature; D015416:Maillard Reaction
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D017127:Glycation End Products, Advanced; D005632:Fructose; D005947:Glucose
keywords: Maillard reaction products; antioxidant; cysteine; enzymatic browning inhibition