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2. Cocci E, Rocculi P, Romani S, Dalla Rosa M.. Influence of antioxidant dipping treatmentand modified atmosphere packaging on nutrient retention in fresh-cut apples. In Book ofAbstract of 3rd Slovenian Congress on Food and Nutrition, Food processing-Innovation-Nutrition-Healthy Consumers, 23-26 September 2007, Radenci, Slovenia, pp. 31.The maintenance of nutritional value of minimally processed (MP) product has not been the primary concernof shippers and producers, who have paid particular attention to safety and organoleptic aspects (Rocculiet al., 2004). Among fresh-cut fruit and vegetable, in recent years the production of MP apples has increaseddramatically and further growth can be anticipated (Pilizota and Sapers, 2004).The aim of this study was to evaluate the effects of an antioxidant dipping treatment and modified atmospherepackaging (MAP) on ascorbic acid (AA) and total polyphenol (TP) contents as well as on the overallantioxidant activity of the water-soluble fraction of minimally processed apples, during 8 days of refrigeratedstorage. Colour, texture and some chemical indices associated with the ripening stage of the product(titrable acidity and soluble solids content) were also evaluated for the estimation of general quality decayof fresh-cut apples during storage at 4°C. Four trials were carried out as the following: ‘Golden Delicious’apple slices dipped or not dipped in an antibrowning aqueous solution (1% ascorbic acid + 1% citric acid)were sealed in polypropylene boxes and conditioned in air (Control) or in a modified atmosphere composedby 90% N2O, 5% O2 and 5% CO2. As a consequence of the anti-browning treatment at the beginning ofstorage, the AA content of dipped samples was about 20-fold higher than not treated ones and remainedhigher until the sixth day of refrigeration. Moreover, the dipping treatment resulted in an increase in the appleslice antioxidant activity, while MA had a negative effect on AA levels. As shown by the positive correlationbetween the AA and TP results, TP levels were higher for treated samples compared to those nottreated over the whole storage period, because of the reducing action of AA that prevented a high level ofTP degradation. Results of the other physico-chemical parameters investigated confirmed the synergisticpreservative effect on the colour of MA, together with the dipping treatment, while structural decay of fruittissue was evident due to the anti-browning chemical agents used (Gil et al., 1998). From a nutritionalstandpoint, the antibrowning dipping treatment adopted could be considered a way to enrich fruit tissue inAA that could further contribute to an increase in the antioxidant activity that normally derives from endogenousbioactive compounds.3. Mrkìc, V., Cocci, E., Dalla Rosa, M., Sacchetti G. (2006). Effect of drying conditionson bioactive compounds and antioxidant activity of broccoli (Brassica oleracea, L.)”.Journal of the Science of Food and Agriculture 86: 1559-1566.The effect of air-drying parameters on antioxidant activity and changes in antioxidant compounds ofbroccoli (Brassica oleracea L.) were studied. Broccoli samples were dried to 70 g kg −1 moisture contentusing temperatures ranging from 50 to 100 °C and air flow-rates from 1.20 to 2.25m s −1 , resulting indrying times from 25 to 90 min. Temperature, owing to its positive effect on the oxidation kinetics, wasnegatively correlated with ascorbic acid and free and total polyphenol contents but not with kaempferol,even though the sample dried at the highest temperature showed the lowest kaempferol content. The airflow-rate was positively correlated with the total (TPP) and free (FPP) polyphenol contents because it ledto a reduction in the drying time. No correlation was found between air flow-rate and kaempferol content.Air flow-rate and temperature positively affected the antioxidant activity by reducing the drying time.High-temperature, short-time processes maximised the antioxidant activity of broccoli owing to thenegative effect of drying time on antioxidant activity. The antioxidant activity of broccoli was positivelyand significantly correlated with the FPP content but not with TPP and kaempferol. The evaluation ofhydroxymethylfurfural content as an indicator of the occurrence of a Maillard reaction in dried broccolidid not support the hypothesis of a contribution of MRPs to the antioxidant activity of dried broccoli.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.it51