"A model system, containing pregelatinized starch, glucose and amino acids heated at 230 degrees C for up to 10 minutes demonstrated that NaCl leads to darker products compared with the same model heated without NaCl (P < 0.05). The same trend was observed in wheat breakfast cereal flakes toasted at 230 degrees C.

"The present study investigated two hypotheses how salt may influence color formation through Maillard Reaction: 1) hygroscopic behavior of salt may change the retention of water during heating and encourage Maillard reactions by improving mobility of reactants; 2) salt has a plasticizing effect and the presence of salt might keep the product in a rubbery state longer while heating, hence improving mobility and Maillard reactions of reactants. The same models (pregelatinized starch, glucose, and amino acids) mixed with several types of plasticizers (NaCl, KCl, or trehalose) and a blank without plasticizer were made and heat-treated under controlled conditions," wrote L. Moreau and colleagues, University of Nottingham.

The researchers concluded, "The presence of plasticizers always led to darker products, but no correlation was found between color formation, the hygroscopic behavior of the system, and its glass transition temperature as measured by phase transition analyzer."

Moreau and colleagues published their study in Cereal Chemistry ("Influence of Sodium Chloride on Color Development of Cereal Model Systems Through Changes in Glass Transition Temperature and Water Retention." Cereal Chemistry, 2009;86(2):232-238).

For additional information, contact L. Moreau, University of Nottingham, Division Food Science, Sutton Bonington Campus, Loughborough LE12 5RD, Leics, United Kingdom.

From the July 6, 2009, Prepared Foods E-dition