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Six anthocyanin pigments were found to be responsible for the red colour of pomegranate juice (cv 'Mollar'). These were analysed quantitatively and qualitatively by HPLC and identified as delphinidin 3-glucoside and 33-diglucoside, cyanidin 3-glucoside and 3,5-diglucoside and pelargonidin 3-glucoside and 3,5-diglucoside. The fruit skin contained only the cyanidin and pelargonidin derivatives. Generally, there is an increase in juice pigmentation with fruit ripening. During early maturation stages the 3,5-diglucosides were the main pigments and the delphinidin-based derivatives were the predominant compounds. In late maturation stages the proportion of monoglucosides increased to reach values similar to or higher than those of the diglucosides, and the cyanidinbased derivatives were the predominant substances. The concentration of pigments in juice obtained from mature pomegranates ranged between 50 and 100 pg of anthocyanin per gram fresh weight of arils. The development of anthocyanins was also tested in fruits produced in two different orchards, and in fruits from different locations in the tree. Red coloured fruits, located in the outer parts of the tree, and yellow fruits, on the inner branches, were analysed. The juices obtained with the seed coats of both fruit types, and from the two orchards selected, showed the same anthocyanin profile. However, the total amount of pigments in the juice was generally smaller in those fruits with reddish skins (outer fruits), than in those with yellow skins (inner fruits). As juice pigmentation is one important quality factor in pomegranate, these results could be used in on-line determinations of the pomegranate quality by non-destructive physical methods.

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The stability of three strawberry cultivars was evaluated for changes in jam color quality during processing and storage at 20°, 30° and 37°C for 200 days. Anthocyanin content was determined by HPLC. The effect of cultivar, processing and storage on jam pigments, instrumental color (L*, a*, b*) and consumer preference were also determined. ‘Oso grande’ jam had the lowest anthocyanin concentration (110 mg/g f.w), higher monomeric pigment degradation during processing and storage, highest pH, least desirable color score from the sensory panel and shortest shelf‐life. Similarities were found between jams prepared with ‘Chandler'and Tudla’ cultivars, as well as initial differences in total anthocyanin concentrations (195 and 130 mg/g f.w.).

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Spanish 'Mollar de Elche' sweet pomegranates (Punica granatum L.) were stored at 2 or 5°C for 12 wk in unperforated polypropylene (UPP) film of 25 µm thickness in modified atmosphere packaging (MAP). Perforated polypropylene (PPP) film of 20 µm thickness and conventional cold storage were applied as control treatments. Quality was evaluated after storage and after shelf life of 6 d at 15°C and 75% RH. PPP at 5°C was the best treatment for maintaining red skin-color of the arils at the end of storage. All treatments suffered a decrease in total anthocyanins content at the end of shelf life. After shelf life, UPP fruits had higher values of absorbance at 510 and 446 nm. MAP strongly reduced water loss and chilling injuries without incidence of decay.

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