Relationship between colour and brown pigment concentration in orange juices subjected to storage temperature abuse

Abstract

SummaryThe browning index of orange juices which had been subjected to storage temperature abuse (55°C for up to 40.5 hr) was highly correlated with the CIE tristimulus values as measured on a Neotec Du‐Color Colour Difference Meter. The correlation coefficients and the multiple regression equation have been calculated. When the tristimulus values were converted to USDA colour scores, the values obtained were not in the same range as the USDA plastic standards for orange juice. The level of correlation between the colour scores and the browning index was too low to be useful for prediction purposes. When the tristimulus values were converted to Hunter's citrus red and citrus yellow parameters, a significant correlation was found between these parameters and the browning index. However, the level of variation explained by the correlation was again too low to be useful for prediction purposes.