Shelf-life kinetic model for freeze-dried oranges using sensory analysis and luminance determination.

Physical (luminance) and sensory variables (color and taste) were used to analyze the aging of freezed-dried oranges slices, determining the influence of temperature and time on aging and evaluating the shelf-life. The highest value in the luminance distribution curve, especially useful when the color of the food products is not uniform, and the color and taste scores obtained in sensory analysis were used to evaluate the shelf-life. Different kinetics models were probed to explain the experimental results but only third-order kinetic model correlated the luminance as a function of time and temperature. This kinetic constant obtained depended on the temperature following an Arrhenius model, giving an activation energy equal to 208 kJ/mol (R = 0.9959). The correlation between physical (luminance) and sensory variables (color and taste) may be used to evaluate the shelf life of the orange slices, finding revealed that at 28 °C the shelf life may expected to be 10 years.