| Abstract
| - The extent of the Maillard reaction was studied by measuring furosine and color formation in infantand enteral formula-resembling model systems prepared by mixing calcium caseinate, laboratory-obtained or commercial whey protein with lactose or dextrinomaltose (ingredients similar to thoseused in infant and enteral formula manufacture) and heating the mixture at 100, 120, or 140 °C for0−30 min. The furosine determination was performed by HPLC and the color determination bymeasuring colorimetric parameters L*, a*, and b* in a reflection photometer. The first steps of theMaillard reaction could be followed by furosine determination when initial ingredients had low thermaldamage. Hence, furosine may be an indicator of low thermal damage in ingredients with <100 mg/100 g of protein. At the concentrations used in these model systems, similar to those in infant andenteral formulas, furosine values (indirect measure of lysine losses) were higher in lactose than indextrinomaltose systems, in which only glucose, maltose, maltotriose, and maltotetraose among allof the sugars present showed reactivity with casein. Finally, the advanced steps could be followedby color determination when the initial ingredients had high thermal damage or the model systemswere heated at high temperature or for a long time. Among the parameters assayed, b* was themost sensitive. Keywords: Milk proteins; lactose; dextrinomaltose; furosine; color
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