28 research outputs found
Chemical–physical characteristics, polyphenolic content and total antioxidant activity of three Italian-grown pomegranate cultivars
Background
In Mediterranean countries, there is an increasing demand for pomegranate fruits due to their antioxidant properties and nutritional values. The large diffusion of new genotypes and cultivars requires the knowledge of all fruit characteristics in connection with the cultivation area, to satisfy the market demand. This study seeks to determine the fruit quality attributes and nutraceutical values of three pomegranate cultivars (Wonderful, Acco and Kamel) grown in the Mediterranean climate.
Methods
The fruits were evaluated for their main physico-chemical traits (weight, volume, height, width, thickness, total arils number, total arils weight, juiciness, fruit index, peel index and total soluble solids content/titratable acidity ratio), bioactive compounds (total phenolic content and total anthocyanin content) and antioxidant activities (radical scavenging activity and ferric reducing power).
Results: The data showed that Acco fruit is bigger, juicier and sweeter when compared with the cultivars Wonderful and Kamel. Wonderful is the smallest, least juicy and least sweet but the reddest among all the studied cultivars. Regarding the phenolic compounds and antioxidant activity (radical scavenging activity and ferric reducing power), cultivar Wonderful has the highest values and cultivar Acco contains the most anthocyanin content.
Conclusions
This study showed that pomegranate cultivars grown in the Mediterranean area exhibit an appreciable quality, but there are significant differences in quality properties of the arils and juice
Effect of three different aloe vera gel-based edible coatings on the quality of fresh-cut “Hayward” kiwifruits
In recent years, the market for minimally processed fruit has increased. Fresh-cut fruits are characterized by a short shelf life due to the processing phases that accelerate the ripening courses. The aim of this work is to analyze the effect on the quality of fresh-cut Hayward kiwis of three different edible coatings based on (1) Aloe vera gel, (2) Aloe vera gel + hydroxypropyl methylcellulose and (3) Aloe vera gel + lemon essential oil. Fruit firmness, weight loss, color, soluble solids content, titratable acidity, microbial load and sensory analysis were evaluated as fresh after 2, 4, 7 and 10 days. Aloe vera gel and Aloe vera gel + lemon essential oil maintained the best values, as they acted as a barrier to gas exchange and further reduced the microbial load. These results were confirmed by sensory analysis: Aloe vera gel + hydroxypropyl methylcellulose does not alter the natural taste of kiwi slices, Aloe vera gel + lemon essential oil gives the characteristic taste of lemon essential oil and Aloe vera gel gives an herbaceous taste. The Aloe vera gel, in combination with these additives, maintains the ability to preserve the quality of fresh-cut kiwifruit
PROGETTO “MESSINA 1908 – 2008”. RAPPORTO DELLA CAMPAGNA OBS NELL’AREA EOLIANA E DELLO STRETTO DI MESSINA
Il Centro Nazionale Terremoti (CNT), in collaborazione con la sezione di Catania, ha progettato e
realizzato un esperimento di sismica passiva nell’area Calabro–Peloritana il cui scopo è fornire nuovi dati
sismici volti a comprendere come le dinamiche superficiali ed il processo di subduzione interagiscano tra
loro, migliorando così la comprensione dei processi sismogenetici nella zona colpita dal terremoto del 1908
[Margheriti et al., 2008; http://dpc-s5.rm.ingv.it].
Con l’obiettivo di ridurre l’errore di localizzazione degli ipocentri degli eventi verificatisi nell’area
interessata dal progetto, ad integrazione delle 30 stazioni della rete sismica nazionale già presenti nell’area in
esame, l’esperimento ha previsto l’installazione di 15 stazioni della rete mobile e la deposizione di 5 OBS/H
(Ocean Bottom Seismometer with Hydrophone), per un numero complessivo di 50 stazioni sismiche larga
banda 3C coinvolte nel progetto.
La campagna sismica a terra ha avuto inizio nell’ottobre 2007 e ad oggi (gennaio 2009), le stazioni
sono ancora in funzione, mentre la deposizione dei cinque OBS/H è avvenuta tra il 15 e il 18 luglio 2008 ed
il loro recupero è stato effettuato tra il 6 e il 7 novembre 2008.
Gli OBS/H, progettati e realizzati presso l’OBS Lab di Gibilmanna, sono stati equipaggiati con
sismometri Nanometrics Trillium 120p (120s - 175 Hz) e con sensori differenziali di pressione (Differential
Pressure Gauge) Cox-Webb, con banda passante tra i 200s e i 2Hz.
La base autolivellante sulla quale è installato il sensore sismico è stata realizzata anch’essa presso
l’OBS Lab di Gibilmanna nei mesi intercorsi tra il recupero degli OBS impiegati nella prima campagna
NERIES, avvenuto nel marzo 2008, e il luglio 2008, data della deposizione degli OBS del progetto “Messina
1908 – 2008”. La necessità di realizzare una nuova base autolivellante in tempi così brevi, è stata una diretta
conseguenza dei risultati negativi ottenuti dalla base Nautilus in occasione della già citata campagna
NERIES [D’Anna et al., 2008]: due sismometri su tre non si erano livellati nel range di ±0.2°, massimo tilt
dinamico previsto per i Trillium 120p, provocando il non funzionamento degli stessi. Come meglio verrà
analizzato nei paragrafi successivi, le problematiche affrontate nella realizzazione di questi dispositivi di
livellamento sono state molteplici e di difficile soluzione. L’analisi preliminare dei dati ha evidenziato che
soltanto uno dei cinque sensori sismici ha funzionato correttamente per l’intero periodo, mentre gli altri
quattro hanno funzionato in media per circa 20 giorni. Causa di ciò, un rapido consumo delle batterie dovuto
ad un livellamento sì compreso nel range di ±0.2° dall’orizzontale, condizione necessaria perché il
sismometro sia in grado di rilevare eventi sismici, ma oltre il range di ±0.1°, condizione necessaria perché i
consumi del Trillium120p si riducano da circa 2.5W ai 600mW nominali.
I risultati ottenuti da questo esperimento, sono comunque da inquadrare in una successione degli
eventi che ha fatto sì che lo sviluppo di questa nuova base autolivellante fosse condizionato da una certa
urgenza: al CNT premeva presentare i dati raccolti dagli OBS al convegno “Scienza e società a 100 anni dal
grande Terremoto”, che si sarebbe tenuto a Reggio Calabria dal 10 al 12 dicembre 2008 e visti gli insuccessi
della base Nautilus nel precedente esperimento, ci si è trovati di fronte alla necessità di progettare e
sviluppare un nuovo sistema di livellamento per i Trillium 120p nell’arco di tre mesi e mezzo. Queste, oltre a
quelle di natura economica, le ragioni per cui non è stato possibile procedere secondo un iter che per noi,
come per le aziende che operano nel settore marino, è uno standard:
- Progettazione;
- Realizzazione del prototipo;
- Test in laboratorio (e. g. tavola vibrante)
- Test in camera iperbarica;
- Test in mare;
- Produzione in serie;
E’ nostra intenzione, in un prossimo futuro, portare avanti lo sviluppo di questa base autolivellante,
con tempi e risorse finanziare ed umane più appropriate. Ciò che riportiamo in questo Rapporto Tecnico
vuole essere una descrizione del lavoro sin qui svolto, anche se non conclusivo e risolutivo, ma che ci ha già
permesso di individuare delle problematiche fondamentali la cui soluzione sarà oggetto di studi più
approfonditi. Rimane positivo il fatto che le basi già realizzate riescono già da adesso a livellare
automaticamente un sensore entro un range di ±0.2°.
Gli OBS/H dell’INGV verranno nuovamente deposti con la stessa disposizione del progetto “Messina
1908 – 2008” nell’estate 2009, nell’ambito del progetto S5 finanziato dal Dipartimento della Protezione Civile. Per sopperire alle problematiche riscontrate nella marinizzazione del Trillium 120p, si è scelto di
installare a bordo degli OBS dei sensori Guralp CMG40T-OBS (60s – 100 Hz), progettati per installazioni in
mare sino a profondità di 6000 m è già dotati di una propria base autolivellante. Il motivo per il quale non si
è utilizzato nelle passate campagne questo tipo di sensore è da addebitare unicamente al fatto che sui fondi
DPC della convenzione 2005-2007 non è stato possibile inserire l’acquisto di questi specifici sensori, mentre
erano disponibili i Trillium 120p
Analysis of Dual-Band Direction of Arrival Estimation in Multipath Scenarios
The present paper analyzes the performance of localization systems, based on dual-band Direction of Arrival (DoA) approach, in multi-path affected scenarios. The implemented DoA estimation, which belongs to the so-called Space and Frequency Division Multiple Access (SFDMA) technique, takes advantage of the use of two uncorrelated communication carrier frequencies, as already demonstrated by the authors. Starting from these results, this paper provides, first, the methodology followed to describe the localization system in the proposed simulation environment, and, as a second step, describes how multi-path effects may be taken into account through a set of full-wave simulations. The latter follows an approach based on the two-ray model. The validation of the proposed approach is demonstrated by simulations over a wide range of virtual scenarios. The analysis of the results highlights the ability of the proposed approach to describe multi-path effects and confirms enhancements in DoA estimation as experimentally evaluated by the same authors. To further assess the performance of the aforementioned simulation environment, a comparison between simulated and measured results was carried out, confirming the capability to predict DoA performance
Assessment of Anchors Constellation Features in RSSI-Based Indoor Positioning Systems for Smart Environments
In this paper, we assess the features of a rectangular constellation of four anchors on the position estimation accuracy of a mobile tag, operating under the IEEE 802.15.4 specifications. Each anchor implements a smart antenna with eight switched beams, which is capable to collect Received Signal Strength Indicator (RSSI) data, exploited to estimate the mobile tag position within a room. We also aim at suggesting a deployment criterion, providing the discussion of the best trade-off between system complexity and positioning accuracy. The assessment validation was conducted experimentally by implementing anchor constellations with different mesh sizes in the same room. Mean accuracies spanning from 0.32 m to 0.7 m on a whole 7.5 m × 6 m room were found by varying the mesh area from 1.19 m2 to 17 m2, respectively
Tray-drying is a new way to valorise white-fleshed peach fruit
Pescabivona is a highly appreciated fruit by consumers for its sweet flavour and juicy flesh; however, it has a short shelf life and is susceptible to postharvest damage, such as mechanical injury, loss of texture and alteration of organoleptic properties. Therefore, it's necessary to develop new methods of processing and conservation for this fruit. The aim of this study was to analyse the effects of tray-drying in white peach slices and cubes at 70 ℃ for 12 hours in order to extend their shelf-life and increase its commercial availability over a long period and to obtain a new food product. The physicochemical and sensory properties of dried fruits were assessed during 30 days of storage in polyamide/polyethene (PA/PE) bags containing two gas mixtures (treatments): MAP-N2 (100% N2) and MAP-P (78% N2, 21% O2 and 0.04% CO2), at room temperature (20 ± 1 ℃). Both MAP treatments kept the fruit firmness, with MAP-P slightly more effective. Slicing produced fruit with a good appearance and firmness, while cubing produced sweet fruit with a caramel flavour and a chewier firmness. In addition, packing with MAP-N2 reduced the phenomenon of fruit browning. Overall, this study provides significant information on the drying process (time-temperature treatments) and packaging techniques (MAP) of white-fleshed peach to obtain a novel food product
Realtime gas emission monitoring at hazardous sites using a distributed point-source sensing infrastructure
This paper describes a distributed point-source monitoring platform for gas level and leakage detection in hazardous environments. The platform, based on a wireless sensor network (WSN) architecture, is organised into sub-networks to be positioned in the plant’s critical areas; each sub-net includes a gateway unit wirelessly connected to the WSN nodes, hence providing an easily deployable, stand-alone infrastructure featuring a high degree of scalability and reconfigurability. Furthermore, the system provides automated calibration routines which can be accomplished by non-specialized maintenance operators without system reliability reduction issues. Internet connectivity is provided via TCP/IP over GPRS (Internet standard protocols over mobile networks) gateways at a one-minute sampling rate. Environmental and process data are forwarded to a remote server and made available to authenticated users through a user interface that provides data rendering in various formats and multi-sensor data fusion. The platform is able to provide real-time plant management with an effective; accurate tool for immediate warning in case of critical events
MICROTREMOR MEASUREMENTS IN PALERMO, ITALY: A COMPARISON WITH MACROSEISMIC INTENSITY AND EARTHQUAKE GROUND MOTION
The city of Palermo is an appropriate test site where the efficiency of microtremors in predicting ground
motion properties during earthquakes can be checked. Palermo is a densely populated city with important
historical heritage and was object of previous studies. Areas of local amplification of damage were identified
in downtown Palermo using historical macroseismic data. Moreover, aftershocks of the September 6, 2002,
earthquake (Mw 5.9, 40 km offshore) provided a dataset of seismograms that quantify spatial variations of
ground motion. The availability of more than 2000 boreholes in the city allowed a reconstruction of the 3D
structure of surface geology, indicating that all the higher damage zones correspond to sediment-filled
valleys. The high variability of the surface geology is mostly due to the presence of two filled river-beds of
about 150 m width. In the framework of the SESAME project (Seismic EffectS assessment using Ambient
Exctations, funded by the European Union), 90 microtremor measurements were performed across several
profiles crossing the soft sediment bodies. The measurement points were intensified close to the valley edges
(every 20 m), according to our geological reconstruction. H/V spectral ratio on ambient noise (HVSR) show
significant variations along each profile: as soon as the transition stiff to soft is crossed, a typical spectral
peak exceeding a factor of 3 in amplitude appears in the HVSR. The peak falls between 1 and 2 Hz and,
along each profile, the peak disappears as soon as the other edge of the valley is crossed. These results
indicate that microtremors are sensitive to the presence of large impedance contrasts of deep soft soil, at least
in the Palermo area, with an important implication: the HVSR method seems to be able to recognize
conditions potentially favourable to the occurrence of higher damage even when local geological characters
are masked by the urban growth. However, we were not able to establish a quantitative correlation between
microtremor properties and ground motion (or damage) amplification
Real-time urban seismic network and structural monitoring by means of accelerometric sensors: Application to the historic buildings of Catania (Italy)
A real-time urban seismic network for seismic and
structural health monitoring is being installed in the city of
Catania (Sicily, Italy). The 27 monitoring stations, specifically
designed and assembled, equipped with a low-noise 3-axial
MEMS accelerometer, are located in 23 high exposure and
vulnerability buildings. In this paper we present the
characteristics of the monitoring station and of the network. In
case of strong seismic events, the system will provide shake maps
to the emergency management centre, and will allow to assess the
health conditions of the monitored buildings. The network is
conceived to be further expandable over the whole historical city
centre of the city of Catania.PublishedMilan, Italy1IT. Reti di monitoraggi
The Use of Opuntia ficus-indica Mucilage and Aloe arborescens as Edible Coatings to Improve the Physical, Chemical, and Microbiological Properties of ‘Hayward’ Kiwifruit Slices
Edible coatings (EC) with mucilage of Opuntia ficus-indica or Aloe arborescens are promising to extend the shelf life of fresh-cut fruit products by reducing weight loss and microbial spoilage. In this work, fresh-cut kiwifruits (cv. Hayward) were coated in solutions with mucilage extracted from Opuntia ficus-indica (MC) and A. arborescens (AL). We used three alternative treatments with AL or MC, MC+AL, and with distilled water as control, and stored in passive atmosphere at 5 °C for 3, 5, 7, and 9 d, respectively. For all treatments at each storage period, firmness, weight loss, color, visual quality score, respiration rate, pectin content, and microbiological characteristics were observed. The treatments with mucilage and A. arborescens applied on fresh-cut kiwi slices showed different significant effects until 9 days of storage, in terms of firmness and total pectin. Microbial spoilage analysis revealed the beneficial effects of this strategy after 3 d, particularly in terms of bacteria and yeast. A. arborescens provided a reduction of microbial activity, probably due to the higher quantity of aloin if related to Aloe species. Furthermore, the treatment with MC and AL increased the total pectin content, showing positive effects in terms weight loss and firmness. The results showed that the MC+AL treatment improved the visual score of fresh-cut kiwi fruit until 7 d of storage