A generic procedure to monitor Maillard-derived fluorescent compounds in cookies by flow-injection analysis


Calvarro J., GÖKMEN V., Morales F. J.

EUROPEAN FOOD RESEARCH AND TECHNOLOGY, vol.229, no.6, pp.843-851, 2009 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 229 Issue: 6
  • Publication Date: 2009
  • Doi Number: 10.1007/s00217-009-1119-8
  • Journal Name: EUROPEAN FOOD RESEARCH AND TECHNOLOGY
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.843-851

Abstract

Flow-injection analysis is proposed for routine measurement of Maillard-derived fluorescent compounds (FC) in cookies as a marker of the extent of baking. In addition, procedure was applied to investigate the formation of free and total (bound to protein free) FC in cookie-resembling models and in commercial wheat-based cookies as well. FC accounts for the overall fluorescence response of Maillard-derived fluorescent compounds (bound or not to protein) formed during baking but not for a single compound. Free and total FC values increased exponentially during baking at 200, 210 and 220 A degrees C and an induction period of 10 min was observed for free FC. In the complex scenario of the progress of the Maillard reaction (MR) during baking, formation of FC (347/415, ext/emm) was not the limiting step for browning development at the advanced stage of the reaction. Furthermore, the formation of Maillard-derived fluorescent compounds and browning during baking were a consequence of parallel reactions apart from the classical MR scheme of consecutive reactions. Total/free FC ratio was dependent on the baking conditions applied and ratio was significantly decreased at severe baking conditions. Total/free FC ratio could be used as a reference marker for monitoring the process and to identify potential over-processing situations during baking. In addition, fluorescent residues were originally bound to protein because total/free FC ratio decreased drastically as increased the temperature and time of the process. Levels of total FC were nearly 20-fold of free FC in commercial samples. Values of FC were positively correlated with acrylamide, a Maillard-derived food processing contaminant.