Since no process has yet been established for the production of cactus pear juice, the present work aimed at the development of a betalainbased
colouring foodstuff from Opuntia ficus-indica cv. dGiallaT and cv. dRossaT of two seasons applying unit operations typical for fruit juice
production. Complete separation of the peels from the pulp and removal of seeds were achieved by carborundum peeling of the frozen fruits
and subsequent passing through a finisher. Furthermore, for improved filtration of cactus pear juice different enzyme preparations were tested
to degrade pectic-like substances. To monitor quality changes in the course of processing, juice samples were analysed after each processing
step in terms of colour and selected chemical parameters. While lightness (L*) and chroma (C*) increased during processing for both
cultivars, hue angle (h8) remained unchanged for the yellow cultivar dGiallaT, but a slight shift towards red was observed for the red cultivar
dRossaT after pasteurisation. Unexpectedly, even after repeated thermal treatment neither non-enzymatic browning nor HMF formation was
observed in juices from both cultivars.
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