The Influence of pH on the Color Development of Melanoidins Formed from Fructose/Amino Acid Enantiomer Model Systems

  • Kim, Ji-Sang (Department of Food and Nutrition, Kyung Hee University) ;
  • Lee, Young-Soon (Department of Food and Nutrition, Kyung Hee University)
  • Published : 2008.12.31


This study investigated the influence of pH on the color development of melanoidins formed from amino acid enantiomer model systems. For this, the color development was evaluated by measuring browning at 420 nm and color measurements by spectrophotometry and colorimetry. The browning and browning index showed no difference according to the type of amino acid enantiomers, while that formed from the D-Asn system was the only difference according to pH level. The tristimulus value of melanoidins formed from all model systems was located on a dominant wavelength of 475 nm, the blue zone of the diagram. In addition, the $L^*$, $a^*$, $b^*$, $C^*_{ab}$ values, and ${\Delta}E^*$ index on the basis of the type of amino acid enantiomers, the differences were markedly found at pH 4.0. At pH 7.0, significantly differences were found in the $L^*$, $a^*$, $b^*$ values, and ${\Delta}E^*$ index and not in the case of the lysine enantiomers. In addition, at pH 10.0, the differences were found in the $a^*$ and $b^*$ values from the lysine enantiomers and $C^*_{ab}$ value from the asparagine enantiomers. Therefore, the color development of melanoidins was influenced by the type of amino acid enantiomers and pH levels. Especially, it is thought that the $a^*$ and $b^*$ values can be used to explain the differences among the amino acid enantiomers in the color development of melanoidins.



  1. Wijewickreme AN, Kitts DD, Durance TD. 1997. Reaction conditions influence the elementary composition and metal chelating affinity of nondialyzable model Maillard reaction products. J Agric Food Chem 45: 4577-4583
  2. Ames JM, Nursten HE. 1989. Recent advances in the chemistry of coloured compounds formed during the Maillard reaction. In Trends in Food Science. Lien WS, Foo CW, eds. Singapore Institute of Food Science and Technology, Singapore. p 8-14
  3. Ames JM. 1992. The Maillard reaction. In Biochemistry of Food Proteins. Hudson BJF, ed. Elsevier Applied Science, London. p 99-153
  4. Ames JM, Apriyantono A, Arnoldi A. 1993. Low molecular weight coloured compounds formed in xylose-lysine model systems. Food Chem 46: 121-127
  5. O'Brien J, Morrissey PA. 1989. Nutritional and toxicological aspects of Maillard Reaction. Crit Rev Food Sci Nutr 28: 211-248
  6. Farmar JG, Ulrich PC, Cerami A. 1988. A novel pyrroles from sulphite-inhibited Maillard reactions: insight into the mechanism of inhibition. J Org Chem 53: 2346-2349
  7. Homma S, Murata M, Fujii M, Lee YS. 1994. Characterization of model melanoidin by lectin affinity and immunochemistry. In Maillard Reactions in Chemistry, Food, and Health. Labuza TP, Reneccius GA, Monnier VM, O'Brien J, Baynes JW, eds. Royal Society of Chemistry, Cambridge, UK. p 424
  8. Motai H, Inoue S. 1974. Conversion of colour components of melanoidin produced from the glycine-xylose system. Agric Biol Chem 38: 233-239
  9. Motai H. 1976. Viscosity of melanoidins formed by oxidative browning. Validity of the equation for a relationship between colour intensity and molecular weight of melanoidin. Agric Biol Chem 40: 1-7
  10. Bruckner H, Justus J, Kirschbaum J. 2001. Saccharide induced racemization of amino acids in the course of the Maillard reaction. Amino Acids 21: 429-433
  11. Patzold R, Bruckner H. 2005. Mass spectrometric detection and formation of D-amino acids in processed plant saps, syrups, and fruit juice concentrates. J Agric Food Chem 53: 9722-9729
  12. Papadakis SE, Abdul-Malek S, Kamdem RE, Yam KL. 2000. A versatile and inexpensive technique for measuring color of foods. Food Tech 54: 48-51
  13. Hunt RWG. 1991. Measuring colour. 2nd ed. Ellis Horwood Ltd., Chichester. p 313
  14. Huidrobo JF, Simal J. 1985. Determination of colour and turbidity of honey. Anales de Bromatologia 36: 225-245
  15. Buera MP, Resnik S. 1990. Colorimetric measurements in a turbid medium: hydrolyzed concentrated cheese whey. Die Farbe 35: 268-272
  16. CIE Colorimetry Committee. 1974. Technical notes: working program on colour differences. J Opt Soc Am 64: 896-897
  17. Morales FJ, Van Boekel MAJS. 1998. A study on advanced Maillard reaction in heated casein/sugar solutions: colour formation. Int Dairy J 8: 907-915
  18. Lozano RD. 1977. Evaluation of different color-difference formulae by means of an experiment on color scaling. Color Res Appl 2: 13-18
  19. Ajandouz EH, Tchiakpe LS, Dalleore F, Benajiba A, Puigserver A. 2001. Effect of pH on caramelization and Maillard reaction kinetics in fructose-lysine model systems. J Food Sci 66: 926-931
  20. Leong LP, Wedzicha BL. 2000. A critical appraisal of the kinetic model for the Maillard browning of glucose and glycine. Food Chem 68: 21-28
  21. Hofmann T. 1998. Studies on the relationship between molecular weight and the color potency of fractions ob-tained by thermal treatment of glucose/amino acid and glucose/protein solutions by using ultracentifugation and color dilution techniques. J Agric Food Chem 46: 3891-3895
  22. Brands C, Wedzicha B, Van Boekel MAJS. 2002. Quantification of melanoidin concentration in sugar-casein systems. J Agric Food Chem 50: 1178-1183
  23. Burton HS, Mc Weeny DJ, Pandhi PN, Biltcliffe DO. 1962. Fluorescent compounds and nonenzymatic browning. Nature 98: 948-950
  24. Buera MP, Petriella C, Lozano RD. 1985. Definition of colour in the non-enzymatic browning. Die Farbe 33: 316-326
  25. Gomyo T, Haiyan L, Miura M, Hayase F, Kato H. 1989. Kinetic aspects of the blue pigment formation in a Maillard reaction between D-xylose and glycine. Agric Biol Chem 53: 949-957
  26. Hayase F, Takahashi Y, Tominaga S, Miura M, Gomyo T, Kato H. 1999. Identification of blue pigment formed in a D-xylose-glycine reaction system. Biosci Biotechnol Biochem 63: 1512-1514
  27. Izydorczyk M. 2005. Understanding the chemistry of food carbohydrates. In Food Carbohydrates: Chemistry, Physical Properties, and Applications. Cui SW, ed. Taylor and Francis, New York, USA. p 44-47
  28. Nursten H. 2005. The Maillard Reaction: Chemistry, Biochemistry, and Implications. The Royal Society of Chemistry, Cambridge. p 1-10
  29. Labuza TP, Saltmarch M. 1980. The non-enzymatic browning reactions as affected by water in foods. In Properties of water related to food quality and stability. Rockland LB, Steward GF, eds. Academic Press, San Francisco, USA. p 605-650
  30. Rhim JW, Jones VA, Swartzel KR. 1988. Kinetics studies in the colour changes of skim milk. Lebensm Wiss Technol 21: 334-338
  31. Pedreschi F, Kaack K, Granby K. 2004. Reduction of acrylamide formation in fried potato slices. Lebensm Wiss Technol 37: 679-685