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Different osmotic solutions, with or without low quantities of added NaCI, were tested to evaluate their effects on the characteristics of the osmosed apples (chosen in our experiences as a fruit "model"). Water loss and water activity of final product were affected not only by the a, of the osmotic agent but also by the gain of solids in the sample. At the same time of treatment, solid gain depended on chemical composition of the syrups and the shape of the samples. Addition of small quantities of NaCl to osmotic solutions increased the driving force of the drying process.

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Since to our knowledge no data are available in the literature regarding the influence of green coffee type and origin on ochratoxin A (OTA) content, determinations were carried out in order to assess the level of OTA contamination in green coffee samples of different provenience. A total of 162 samples of green coffee beans from various countries (84 from Africa, 60 from America, and 18 from Asia) were analyzed for OTA. Both the amount and the variability of OTA levels were tested as a function of green coffee provenience. The results showed that 106 of the overall samples were positive for OTA, with concentration ranging from 0 to 48 microg/kg (ppb). In particular, it was possible to verify that African samples were more contaminated with respect to samples of other origin in terms of frequency and level of OTA; the highest concentrations observed were 18 and 48 microg/kg in two samples from The Congo.

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The effect of air-drying parameters on antioxidant activity and changes in antioxidant compounds of broccoli (Brassica oleracea L.) were studied. Broccoli samples were dried to 70 g kg −1 moisture content using temperatures ranging from 50 to 100 • C and air flow-rates from 1.20 to 2.25 m s −1 , resulting in drying times from 25 to 90 min. Temperature, owing to its positive effect on the oxidation kinetics, was negatively 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 air flow-rate was positively correlated with the total (TPP) and free (FPP) polyphenol contents because it led to 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 the negative effect of drying time on antioxidant activity. The antioxidant activity of broccoli was positively and significantly correlated with the FPP content but not with TPP and kaempferol. The evaluation of hydroxymethylfurfural content as an indicator of the occurrence of a Maillard reaction in dried broccoli did not support the hypothesis of a contribution of MRPs to the antioxidant activity of dried broccoli. INTRODUCTIONThe health-promoting capacity of plant foods depends strictly on their processing history. 1 The conditions of storage, processing and preparation have been proved to have significant effects on the content of antioxidants 2,3 but the impact of processing on the antioxidant activity of vegetables is still a neglected area and little information is available. 2 Broccoli is a vegetable that shows high antioxidant activity owing to the presence of bioactive compounds, 4 -8 among which polyphenols seem to be have the greatest effect. 8,9 The effect of thermal treatment (cooking) on the polyphenol content of broccoli 10,11 and the effect of freezing on polyphenol content and antioxidant activity 12 have been studied, but the effect of processing on the antioxidant activity of these vegetables is still mostly unknown. One study has been carried out on the quality of dehydrated broccoli, 13 but the effect of drying on the antioxidant activity of broccoli was not considered.Several studies investigated the antioxidant activity changes after drying of tomatoes 14,15 and onion powders 16 and in both cases there was an increase in antioxidant activity due to hot air-drying. In the case of tomato, it was hypothesised that the