Dipartimento di Scienze
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Freezing Storage can Affect the Oxidative Stability of Not Filtered Extra-Virgin Olive Oils

Lorenzo Cerretani, Alessandra Bendini, Barbara Biguzzi, Giovanni Lerker, Tullia Gallina Toschi

In this work the changes, induced by a freezing storage, on the phenolic fraction of not filtered extra-virgin olive oils were investigated. Particularly, oil samples from three olive cultivars, coming from two different geographical areas (Italy), were analysed freshly and after a storage at -43°C for three month, by the following procedures: total phenols and o-diphenols by spectrophotometric assays, phenolic profile by HPLC-DAD/MSD analysis, evaluation of oxidative stability by OSI and antiradical power by DPPH tests. Furthermore, the effect of filtration (on cellulose) applied on the samples after the freezing storage, was investigated by the same analytical scheme. Then, the filtered oil was deprived of the phenolic fraction, extracted by a liquid-liquid procedure, and the oxidative stability of the residual oil was tested again.

pectrofluorometry of Essential Oils: Bergamot Oil

Pasquale Giungato, Luigi Notaricola

Bergamot (Citrus bergamia, Risso et Poiteau) cultivation started in Italy at the beginning of the 18th century. Italian bergamot production is limited in a narrow strip of the Calabrian coast, along the Ionian and the Thyrrenian seas. Bergamot is cultivated for the essential oil representing an important raw material for cosmetic and food industry.
Among non-volatile fraction components of the bergamot essential oil there are coumarins, whose fluorescence was widely investigated in the past. Because of their structural diversity and diverse occurrence, these oxygenated heterocyclic compounds have an important role in the identification of the quality and genuineness of the bergamot essential oil.
This review reports spectrofluorometric properties of bergamot essential oil. From excitation-emission matrix (EEM) analysis of bergamot essential oil solutions in ethanol characteristic emissions of citropten, linalyl acetate and that of chlorophills have been detected. One citropten emission has been used in quantitative determination while none of linalyl acetate.
Quantitative fluorometric determination of citropten gives the sum of both citropten and 7-methoxy-5-geranyloxy-coumarin concentration.

Guidelines, Sense and Procedure for Grouping a Wide Assortment of Goods Using a Given Technique in Homogeneous Concentrations as Regards Quality

Stanislaw Hornik

In the present article the procedure for creating homogeneous concentrations of goods produced by using one technique has been described. Enamelled products were taken under consideration. These products had different levels of utility characteristics because the conditions of their utilization were different. The idea of Euclide's distance was used for this reason, because it proves the differences in the levels of characteristics.
The initial database was created with the results of the poll carried out among skilled staff employed in field of enamel products. The level of consumer expectations was the subject of poll. It was defined in a five-point scale. The application of effective grouping of products, which have very similar level of consumer expectations, could have great technical and economic importance.

Preliminary Investigation on Three Extraction Methods of Phenolic Compounds From Olive Mill Wastewatere

Lorenzo Cerretani, Alessandra Bendini, Barbara Biguzzi, Giovanni Lerker, Tullia Gallina Toschi

The main by-product of olive oil processing is a mill wastewater, which is characterized by high concentration of phenolic substances (currently polyphenols). In this paper, the isolation of such substances from olive mill wastewater, by different methods, was tested and discussed. Particularly, solid-phase extraction and liquid-liquid methods were compared, in which two different procedures are illustrated for the last method. Quantification of phenolic and o-diphenolic substances in the extracts was performed by the traditional Folin-Ciocalteau method and the sodium molybdate reaction, respectively. The evaluation of their effectiveness was based on thin layer chromatography (TLC). Furthermore, the traces relative to phenolic compounds in the extracts were carried and the tentative identification of six peaks was carried out by HPLC with diode array (DAD) and mass spectrometric detection (MSD).

Characterization of flavonol compounds from Sardinian fruits using high-performance liquid chromatography

Sonia Ledda, Mario Andrea Franco, Giovanna Sanna, Gavina Manca

Typical fruits of Sardinia, both wild and cultivated, picked in different areas of the island were analysed to determine their content in flavonol compounds. Fresh fruits underwent an extraction process with an acetone/water mixture (70:30, v/v). Three antioxidant flavonol species, quercetin, myricetin and kaempferol glycosides were extracted. Hydrolysis of the glycosylated forms with trifluoroacetic acid, followed by HPLC analysis and plotted gradient, resulted in an optimal separation of the flavonols under examination and qualitative and quantitative determination of the aglycons present. The flavonol present in the highest quantity in almost all the fruits analysed was quercetin, followed by kaempferol and myricetin. On the other hand, myricetin was the major flavonol present in myrtle (1,327 mg/L).

Micro-extraction procedure for Monitoring organochLoride pesticides in water samples

Anna Maria Tarola, Laura Gobbi, Vanessa Giannetti, Filomena Milano, Francesco di Folco

The proposed method, based on liquid-liquid micro-extraction followed by gas-chromatography, is suitable for monitoring organic-chlorine pesticides in different kind of water matrices: mineral, rain, river and waste water. Using this method only 1 mL of extractive organic solvent every 200 mL of water sample is needed. The complete separation of hexane from an aqueous matrix by means of a micro-extractor system gives an good recovery in the case of drinking water and also in the case of aqueous matrices containing a large amount of organic compounds. The objective of this work was to develop a rapid, simple and economic procedure involving a low consumption of toxic solvent organic in screening analyses to determine the presence of organic-chlorine pesticides in water.

RFID: feature of technologies and applications in a concrete experimental environment

Fabrizio D'Ascenzo

RFID technologies are not brand new anymore as a principle of communication using radio frequencies but their application on production and services sector still is uncertain because, in spite of an evident series of advantage, a deep evaluation concerning economical implication has to be made case by case. From this derives that is necessary an experimental activity and this is the way that most of the industries are following at the present moment. An important contribute to this experimental activity and to research can be provided by a test center recently established in University "La Sapienza": RFID-Lab. This paper aims to describe advantages, disadvantages and functionalities of RFID technologies and to explain which are the activities conducted in RFID-Lab.

Use of vegetable bioindicators to measure pollution in sites with different levels of environmental impact

Patrizia Papetti, Enrica Iannucci

Vegetable species can indicate the presence of polluting elements -such as heavy metals- in the atmosphere thanks to a process of accumulation related to leaves morphology and to the present concentration of the hosting area. This biomonitorage system can be considered complementary to the traditional chemical-physical ones to determine food quality, in case they are absent or insufficient. These bioindicators analyze the presence of copper, iron, nickel and manganese in agricultural areas exposed to the action of polluting agents by using vegetables that are largely cultivated and whose foliage show different morphological characteristics and life cycles. The experimentation area is the province of Latina. The plan has been developed as follows:
-determination and characterization of the vegetable products from the province of Latin;
-setting up of analytical methodologies to determine the residuals quantitatively;
-determination of the levels of persistence of the residuals in the vegetable products.