COLOR CHANGES IN CONCENTRATED FRUIT PULP DURING HEATING AT HIGH-TEMPERATURES

The colour change in concentrated apple, peach and plum pulp due to ex tended heat treatment was investigated. Colour differences (Delta E) a nd Hunter L parameters were used to estimate the severity of damage du ring heating of the fruit pulp at 56, 66, 80 and 94 degrees C for 700 min. The results indicate apparent first-order kinetics. Hunter a and b and CIE x and y parameters provided information on changes in chroma tic attributes after severe heat treatment. The analysis of darn conce rning the rate of colour deterioration in concentrated fruit pulps as a function of temperature suggests that more that one mechanism is inv olved. (C) 1997 Elsevier Science Limited.