食品中有机化学论文.pdf

Food Chemistry 137 (2013) 92–98 Contents lists available at SciVerse ScienceDirect Food Chemistry journal homepage: www.elsevi /locat e/foodchem Antioxidant activity of Maillard reaction products (MRPs) derived from fructose–lysine and ribose–lysine model systems Lusani Norah Vhangani ⇑, Jessy Van Wyk Department of Food Technology, Cape Peninsula University of Technology, Bellville 7535, South Africa a r t i c l e i n f o a b s t r a c t Article history: Maillard reaction products (MRPs) were prepared from aqueous ribose–lysine (RL) and fructose–lysine Received 27 January 2012 (FL) model systems at pH 9, heated at 60, 80 and 120 C for 15, 60 and 120 min. Browning intensity Received in revised form 1 August 2012 (BI) and pH reduction were monitored throughout the reaction. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH- Accepted 5 September 2012 RS), peroxyl (PRS), and hydroxyl radical scavenging (HRS) and reducing power (RP) measured their anti- Available online 16 September 2012 oxidant activity. The pH of FL and RL system decreased (p 0.05) as reaction temperatures and times increased. This reduction coincided with the increase (p 0.05) in BI for all MRPs. With the exception Keywords: of HRS activity, the antioxidant activity of FL increased (p 0.05) with increased reaction temperature, Maillard reaction products