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Mature green olives (Olea europea L.) were dried in a forced air oven at 50ºC, after being subjected alternatively to four different pre-treatments. Results indicate the possibility to obtain bitter-free and high quality olives by combining a ten minutes dip in a 10 % hot brine (50ºC) followed by a 32 hours dehydration. The latter product reached 20 % of residual humidity and did not rotted for one year.Se han deshidratado aceitunas verdes de mesa en horno a temperatura de 50ºC tras ser sometidas, alternativamente, a cuatro pretratamientos diferentes para ayudar a su desecación. Los resultados mostraron que es posible obtener aceitunas exentas de amargor y de alta calidad combinando su inmersión en salmuera caliente (50ºC), a una concentración del 10 % en NaCl durante 10 minutos, seguida de una deshidratación durante 32 horas. Las aceitunas deshidratadas alcanzaron una humedad residual del 20 % y no manifestaron signos de putrefacción en un año.

Storage behaviour of 'Core', 'Core Columbu', 'Fradis' and 'Meloni' white prunes, and a black one ('Sighera') of Sardinian germplasm were evaluated following immersion for 0 (control), 15, 30, 45 or 60 sec in water at 20, 50, 55 or 60 degrees C with or without 2% (w/v) NaHCO3 (SBC). As international varieties, fruit from one white plum ('Shiro') and one black prune ('Stanly') were subjected to the same treatments. Fruit was harvested at commercial maturity, treated and then stored for 1 month at 5 degrees C and 90% RH followed by a simulated marketing period at 20 degrees C and 80% RH for 6 days. Fruit appearance, external damage, firmness and decay percentage were monitored after storage and SMP. Treatments did not induce rind damage (browning or discoloration) to any variety. SBC at 20, 45, 50 or 55 degrees C for 15 or 30 sec was not effective in controlling decay and compared to controls no improvement was observed. Immersion for 45 or 60 sec with SBC at all temperatures improved decay control with respect to controls and best results were obtained at 50 or 55 degrees C. Immersions at 60 degrees C improved decay control, but differences were not significant compared to the control attained with solutions of SBC heated at 55 degrees C. The overall appearance of 'Core', 'Core Columbu', 'Fradis' and 'Shiro' decreased significantly after the SMP period, especially when treated at 55 or 60 degrees C for 60 sec. Fruit shrivel was the main cause of the low rating. SBC did not affect shrivel indicating that heat treatment may be the probable cause. In general, local varieties were less affected by decay than other varieties and they performed well during stora

Fresh fruits and vegetables had both an important nutrition-health and an economic value. According to the new dietary guidelines, fresh fruit and vegetables were at the fundament of the nutritional pyramid and were, within our global food package, the best carriers of bio-active substances such as vitamins, minerals, dietary fibres, phenolic antioxidants, glucosinolates and other bioactive components. The main objective of this Action was to enhance and preserve fruit quality, safety and the amount of nutritional and functional components in fresh fruits and vegetables in an integrated approach from orchard to consumer with special attention to organic growing.

Gli agrumi, per le loro peculiari caratteristiche fisiologiche e morfologiche, oltre che come prodotto fresco o destinato all’industria dei succhi, possono essere commercializzati come prodotti minimamente trasformati. In tale contesto, l’Unità di Sassari, ha studiato la possibilità di trasformazione di mandarini e simili come prodotti di IV gamma. Sono stati presi in considerazione gli aspetti legati alle problematiche di tipo tecnologico e l’evoluzione delle caratteristiche nutrizionali durante la conservazione. I risultati ottenuti hanno evidenziato la buona attitudine dei mandarini e simili ad essere preparati come prodotti di IV gamma in grado di mantenere inalterate le caratteristiche fisiche e nutrizionali per un periodo di 10 giorni.

The biocontrol yeast Rhodotorula glutinis, isolate 21A, obtained from tomato fruit was used to control Penicillium digitatum, P. italicum and Botrytis cinerea on artificially wounded citrus fruit. Orange and satsuma mandarin fruit were treated with the biocontrol yeast, inoculated with the pathogens and stored for 7 days at 23 degrees C. On orange fruit the antagonist compared to the control reduced decay by 92.2, 88.4 and 96.2% for P. digitatum, P. italicum and B. cinerea, respectively. On satsuma mandarin fruit the same pathogens were inhibited by 96.2, 91.2 and 90.0%, respectively. Scanning electron microscope observations, focusing on the antagonist-pathogen interactions, revealed a fast colonization of the growing fungal mycelia by the yeast cells, but no sign of lytic activity on hyphae was observed. Moreover, the fruit accumulated the phytoalexins scoparone and scopoletin into artificial wounds previously treated by the yeast and either inoculated or uninoculated with the pathogen. The concentration of scoparone, which showed higher accumulation in fruit tissues, varied significantly in relation to the time lag between the application of the antagonist and the inoculation with the pathogen. In particular, the concentration of scoparone 4 days after application of the sole yeast was 69.0 microg x g(-1) fresh weight (FW), 6.3 times higher than in the uninoculated wounded tissues (11.0 microg x g(-1) FW). The phytoalexin accumulation was low (13.0 microg x g(-1)FW) applying the yeast jointly with P. digitatum into wounds, while it increased consistently (74.0 microg x g(-1)FW) when the antagonist was applied 24 h before the pathogen.

Treatments as hot water dips or high temperature conditioning have been proven to be effective to control postharvest decay on various horticultural crops. These treatments reduce chilling injury and rot losses without causing detrimental effects on fruit firmness, flavour, taste or peel appearance. These technologies, aimed to control postharvest pathogens, can be easily matched with the use of "Generally Recognized as Safe" (G.R.A.S.) compounds and employed alternatively to pesticides, known to be harmful to health and environment. In this respect we studied the combined effect of sodium carbonate (SC) and hot water on the storability of black fig fruit cultivar 'Niedda Longa' of Sardinian germplasm. Second crop fig fruit, harvested in the middle of September, was dipped for one minute in water solutions containing 0, 0.05, 0.5, and 1% (w/v) of SC at 25 or 60 degrees C and then stored at 5 degrees C and 90% relative humidity (RH) for two weeks. After one and two weeks of storage decay, weight loss were monitored and visual assessment was scored. Treatments with hot solutions were more effective in controlling decay compared to cold ones and the best results were achieved with 0.5% of SC at 60 degrees C. This combination reduced the decay rate from 26% (control) to 0% after 1 week and from 50% to 14% after two weeks of storage, respectively. Lower or higher SC concentrations applied at 60 degrees C were less effective and, after two weeks of storage, decay percentages were 38 and 43.6%, respectively. Water dip at 60 degrees C did not affect the weight loss as compared to dips at 25 degrees C either after one or two weeks of storage. At the same time, a significant reduction was found only with 1% of SC at 25 degrees C. The fruit treated with 0.5% of SC at 60 degrees C also had the best visual assessment up to two weeks of storage.

In the last years there has been a growing interest toward minimally processed fruits and vegetables for their convenience of use and freshness. So' far, the major share of the market in Italy is mainly veqetables, whereas the consumption of fruit is stili limited to few species ..This could be in part due to the high perishability of cut fruit which have a very short shelf-life. This' study was aimed at evaluating the potential of different cultivars of mandarins and mandarin- like to be minimally processed. Different technological solutions in the operations of peeling and division of the segments were tested.

Generally recognised as save compounds (G.R.A.S) are attractive substitutes to synthetic chemicals in postharvest control diseases. They meet safety requirements, are cheap and able to be integrated with other disease control technologies. Among G.R.A.S compounds, carbonic acid salts have been investigated on carrots, bell pepper, melons, sweet cherries and their efficacy was also evaluated when combined with biological control agents. Moreover, the possibility to use sodium carbonate and sodium bicarbonate to prevent P. digitatum an P. italicum spread on Citrus fruit was studied since the begin of the 20th century. We explored the possibility to extend the use of carbonate-bicarbonate salts on loquat fruit in order to control the pathogens and to extend postharvest life. Loquat is a very perishable fruit, susceptible to decay, mechanical damage, moisture and nutritional losses during its postharvest life. We tested the combined effect of temperature and sodium or potassium carbonate-bicarbonate and ammonium carbonate. The fruit was dipped in the salt solutions at variable concentrations (0.5, 1 and 2% w/v) at 25 or 45 degrees C for two minutes and than stored under shelf life conditions (25 degrees C and 70% RH). Decay, weight loss, pH, titrable acidity and sugar content were detected after twelve days. Preliminary data show that the combined treatments were effective in decay control depending on salts. Best results were obtained with 2% potassium and sodium carbonate solution at 25 degrees C. Weight losses were related to treatment temperature and salts concentrations whereas, no differences were detected in the chemical parameters compared to the control.

Health and environmental concerns have point out the need to improve or change several manufacturing steps in the food chain. In this context, particular attention should be given to the technologies involved in fruits and vegetables production. Nearly all fresh fruit and vegetables are subjected to different periods of storage and/or shelf-life before of their consumption. This implies the need to protect the commodities from microbial spoilage. Some Citrus species (e.g. lemon and grapefruit) may be stored for several months before consumption and then postharvest treatments are essential to contain green (Penicillium digitatum) and blue (P. italicum) moulds. Alternative approaches to chemicals usually have a lower efficacy in containing rots but fulfil the consumer's expectation. Among the alternative strategies, the improvement of host natural resistance is promising. In this regard, we report some results concerning the use of biotic (yeast) and abiotic agents as inducers of phytoalexin (i.e. scoparone and/or scopoletin) accumulation in Citrus rind and its importance in the control of fungal decay. In all experiments, the inducers were applied on fruits before or 24 h after inoculation with P. digitatum and the rot severity was monitored 7 days later. The accumulation of phytoalexins was monitored according to a standard methodology by HPLC. In all experiments a positive correlation was found between increase of the phytoalexin scoparone in host tissue and reduction of decay.

Viene valutato l'effetto che la nuova normativa europea impone per la commercializzazione del carciofo. Lo studio è stato condotto con carciofi spinosi endemici della Sardegna coltivati secondo le pratiche standard e preparati: 1) secondo il metodo tradizionale; 2) secondo la nuova neomativa EU. Dopo la raccolta prima e dopo l'idrocooling e durante la shelf-life sono stati monitorati alcuni parametri fisiologici (etilene, respirazione, calo peso, sviluppo di patologie postraccolta e consistenza del capolino). Queste osservazioni sono state effettuate su capolini preparati secondo il metodo tradizionale (con 2-3 foglie e gambo di 30 cm) e su quelli preparati secondo le nuove normative (gambo 20-25 cm senza foglie). I risultati hanno chiaramente evidenziato come il metodo di commercializzazione con le foglie riduce significativamente il periodo della shelf-life e favorisce la comparsa della Botytis cinerea.

Objective of this study was to investigate on the potential use of two different cultivars of mandarins, "Ponkan" and "Page" (Minneola tangelo x Clementine), as minimally processed fruits. Fruit was peeled and separated manually in segments, sealed in polystyrene trays using a polyolefinic film and stored at two 1 or 5 C for 9 days. The following analysis and subjective evaluations were carried out: chemical analysis of the juice, processing characteristics, in package CO2, O2 and C2H4 concentration and microbiological assessments. The overall results indicate a better behaviour of both cultivars at 1 C than at 5 C, while Ponkan showed to be more suitable for processing than Page.