EFFECT OF TEMPERATURE AND SOLUBLE SOLIDS CONTENT ON NONENZYMATIC BROWNING KINETICS FOR CLARIFIED APPLE JUICES

The kinetics of nonenzymatic browning at different temperatures (60, 70, 80, 85, 90, and 95 degrees C) of clarified apple juices, for the varieties Granny Smith and Jonagold with different soluble solids content were studied. The browning was followed by the variation of absorbance at 420 nm (A(420)) Browning was described by a zero-order kinetical model. The effect of temperature on kinetic constants can be described by an Arrhenius-type equation. The effect of soluble solids content on the Arrhenius equation parameters are described by a power-law equation. The Granny Smith juices present a nonenzymatic browning which was more pronounced than Jonagold juices.