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of the red color index a * for Tarocco ‘TDV’ packaged with B and C films were observed. No correlation betweenthis color index and anthocyanin content in the slices (R 2 = 0.08 for film B, R 2 = 0.07 for film C) was observed,due to the high variability in the distribution of the pigments in the juice sacs. Therefore, the choice of the bestcultivar and film suitable for the production of minimally processed blood oranges was assigned to sensory andmicrobiological analyses. The best sensory results were obtained with Tarocco fruits packaged with the threefilms, since no statistical difference among the storage days was observed. Regarding cv. Sanguinello, a SA decreasingof about 25-28% was observed in products packaged with the three films. A similar behavior was observedin cv. Moro, even if sensory analyses of products packaged with the three films were stopped at the 10 thday of storage, since slices were not pleasant to sight. Regarding microbiological analysis results, mould andyeast were the most worrying microorganisms. In fact, orange sample contamination was high after the 6 th storageday, but, with regard to the other examined microorganisms, yeast exceeded the CNERNA-CNRS (1996)values. Among the cultivars, the worst results were obtained with cv. Moro; in fact, the number of most detectedmicrobial groups, expressed as log CFU/g, was higher than 10 8 especially between the 9 th and 12 th storage days.With respect to the packaging films, no important differences in sensory and microbiological values were observedamong the different orange cultivars studied.3) RAPISARDA P., CAGGIA C., LANZA C.M., BELLOMO S.E., PANNUZZO P.,RESTUCCIA C. (2006). Physiochemical, microbiological, and sensory evaluation ofminimally processed Tarocco clone oranges packaged with 3 different permeability films. J.Food Sci. 71:299-306.The results of our research affirm that during the 14 to 15 d of storage, the sliced oranges obtained from differentTarocco clones packaged in heat-sealed boxes with different permeability films did not show markedphysicochemical changes. The sensory data showed that the minimally processed Tarocco clones packaged withfilm C were the most appreciated because this film probably prevented the formation and/or favoured theremoving of the off-flavour, whose presence negatively influences the product evaluation. Regarding themicrobiological results, the number of all detected microbial groups, expressed as CFU/g, was lower thanestablished by microbiological criteria for minimally processed fruits and vegetables.4) Catalano A.E., Ingallinera B., Todaro A., Rapisarda P., Spagna G. (2009) Degradativeenzymatic activities in fresh-cut blood-orange slices during chilled-storage. InternationalJournal of Food Science and Technology 44, 1041–1049Blood-orange fruits are suitable to fresh-cut fruit production because of their chemicalcompositions.Nevertheless, the main limitation of using freshly cut oranges is their susceptibility to juicinessloss and ascorbic acid degradation because of enzymatic alterations. The aim of this work is: to identify some ofthe enzymes causing the qualitative decay in blood-orange slices during 15 days of chilled storage (at 4 ± 0.5 _Cand 85% RH); to investigate the susceptibility to the previous alterations of five blood-orange clones (Moronucellare, Sanguinello nucellare, Tarocco arcimusa, Tarocco gallo and Tarocco meli) to select the most suitableone for fresh-cut production. The enzymes studied were: pectinmethylesterase (PME) as index of juiciness loss,ascorbate oxidase (AAO) as index of ascorbic acid’s degradation and polyphenol oxidase (PPO) as browningindex. As far as we know, the changes of AAO activity during chilled storage of blood-orange freshcut slices hasnot previously reported and studied. Different clones showed different enzymatic activities and quality changesduring chilled-storage. In particular a low juiciness loss in orange slices was correlated with a lower PMEactivity, as described in T. meli clone, while a high degradation of ascorbic acid was correlated with an higherAAO activity, as described in T. gallo clone; PPO activity seemed to have no significant action in qualitydegradation. Tarocco meli was the most suitable clone to the fresh-cut blood-orange production because it hasthe lowest enzymatic activity (PME, PPO and AAO) and the highest sensorial quality.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it81