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Salami are a typical seasoned sausage of Italy; a number of types are produced, according to local traditional recipes. As industrial production has taken place, a number of problems rise in obtaining products similar to the traditional ones. The use of selected microbial starters is permitted by Italian law for some years and at present, microbiological research is engaged in selecting starters similar to the ones isolated from traditional products, with the aim of obtaining organoleptic characteristics close to the ones of traditional recipes. A study was carried out concerning the characterisation of volatile components of salami by headspace capillary gas chromatography-mass spectrometry. As during the sampling step, analytes could reach the analytical column, the carrier gas rate was back flushed in the latter, while a pre column was used as cold trap. Then GC-MS analysis follows. By these techniques, we were able to highlight typical profiles of different salami, as well as monitoring the ripening of a traditional and a starter added salami. Main peaks are of fermentative origin, while also peaks from spices were detected. Ethyl propionate was used as internal standard to be able to normalise the peaks amounts.

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Nine trace elements (Cr, Mn, Fe, Ni, Cu, Zn, Mo, Cd, and Pb) were determined in the dissolved ash of 36 samples of raw milk. The distribution of the concentration of each element was first investigated by means of a test of normality. The matrix of the correlation between the concentrations of the elements was then used as a starting matrix for principal component analysis. Nine variables were reduced to four principal components, accounting for 75% of the total variance. The biophilic elements Mn-Fe and Cu-Mo were positively associated with the first two principal components, while Cr was correlated to the third and Ni and Cd with the fourth principal component. Pb and Zn are both negatively correlated to the first principal component. Comparison with 42 samples of a commercial milk, by using a two-dimensional plot of the principal component scores, rendered possible the differentiation between raw and commercial milk.

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Nine trace elements (Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd, Pb) were determined in cheese by atomic absorption spectrophotometry with electrothermal atomization in a graphite tube, using the ashing procedure. Associations among mineral constituents were studied by means of principal component analysis, which allows determination of interdependences among trace elements in foods. A test for normality was used to investigate monovariate distributions, in order to estimate the symmetry of data vector. The correlation matrix was used as a starting matrix for principal component analysis; nine variables were reduced to four principal components. The clusters of elements appear to be determined by their origin.

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The matrix of the correlation between the concentrations of 11 trace elements determined in 45 samples of cows' milk was used as a starting matrix for principal component analysis. The space dimension was reduced from 11 variables to 5 principal components, accounting for about 80% of the total variance. After an orthogonal rotation, the first factor (F1) was found to be positively correlated with Cr, Mn, and Fe, F2 positively correlated with Ni and negatively with Cu, F3 positively with Cd and Pb, F4 positively with Zn, Sr, and Mo and F5 positively correlated with A1 and Sr. Element clusters appear to be determined by their origin. Some clusters are confirmed by principal factor analysis. A plot of the principal component scores was also applied to the differentiation of Italian Milk from different geographical origins.

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Chromium and nickel concentration in roadside unwashed wine grapes and leaves is considered as a function of the distance from the suspected source, an isolated straight road. The analyses were performed with electrothermal atomization in a graphite furnace. The decrease in the concentration of the element can be described by means of a three-parameter exponential function c = A + (B - A)exp(-Cd), which allows the determination of the asymptotic level far from the emitting source (C infinity) and the pollution level (C0) at the edge of the road (d = 0). Least-squares nonlinear regression gives the estimation of the parameters A, B, and C. The results indicate that an effect is detectable up to a distance of about 50 m.

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The total concentration of Cu, Zn and Pb in surface sea waters from the Bay of Muggia (Gulf of Trieste, Northern Adriatic Sea) was determined by anodic stripping voltammetry. The association of these trace elements in relation to the known sources of pollution was discussed. The content of eight trace elements (Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb) in the soft part of mussels (Mytilus galloprovincialis Lamarck) is also considered. The wild molluscs were sampled in the harbour of Trieste, in the proximity of an important city sewer. Principal component analysis was used to analyse the correlation matrix obtained from an 8 x 43 data matrix after a logarithmic transformation of the concentration variables. Eight variables were reduced to four principal components, which explained 80% of the total variance. The orthogonally rotated factor matrix shows that Co, Ni, Cd, and Pb are associated with the first principal component, Cu and Zn to the second, Hg to the third and Mn to the fourth principal component. The results of this multivariate data analysis are compared with those already obtained from two sampling sites in the Bay of Muggia and the origin of some trace metals in the soft part of mussels from the Gulf of Trieste is discussed.

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The chromatographic profiles of carotenoids from some marine shellfish are reported. The analyses were performed both by gradient elution reversed-phase and isocratic direct phase high-performance liquid chromatography (HPLC), and the results obtained are compared and discussed. The six main carotenoids extracted from three shellfish species (Chlamys opercularis, L., Cardium tuberculatum, L., Pecten jacobaeus, L.) were isolated in highly pure form by means of semi-preparative HPLC. They were characterized by means of spectroscopic methods (visible absorption and infrared spectroscopy), and chemical tests: the identification of fucoxanthin and alloxanthin was possible while a tentative identification of two other carotenoids (fucoxanthinol and diatoxanthin) was suggested. Carotenoids in clams and scallops were present both in esterified and free form, while in cardia only carotenoid esters were detected.

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Principal component analysis has been applied to analyze the correlation matrix obtained from a 8 X 43 data matrix. The 8 trace metals are Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb, which are contained in the soft part of mussels (Mytilus galloprovincialis Lamarck). Mussels were sampled from two sites in the Gulf of Trieste. In both samples, 76-78% of the total variance is explained by the four principal components. The orthogonally rotated factor matrix indicates that Co and Ni are bonded to the first principal component and Cd and Pb to the first (site 2) or second principal component (site 1). The origin of trace metals in the soft part of mussels from the Gulf of Trieste is discussed.

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Principal component analysis has been applied to analyze the correlation matrix obtained from a (6 X 44) data matrix. The 6 trace metals are Co, Ni, Cu, Cd, Hg, and Pb, which are contained in the soft part of edible mussels (Mytilus galloprovincialis Lamarck) from a hatchery on the gulf of Trieste. In the space of "eigenvectors", the dimensions are reduced to 3 principal axes, which account for about 77% of the total variance. The unrotated factor matrix obtained by the principal components shows that Co, Ni and Cu are bonded to the first principal component, Cd and Pb to the second, Hg to the third. This picture is also assessed by the Varimax-rotated matrix and it is tentatively explained, at least in part, by considering the associations of the trace metals from various geographical sources.

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The concentration of heavy metals (cobalt, nickel, copper, cadmium, mercury and lead), which are present at trace levels in the edible part of mussels (Mytilus galloprovincialis Lamarck) from hatcheries in the gulf of Trieste, is normally or log-normally distributed, according to a statistical test sensitive to asymmetry of the distribution. A log-normal distribution appears valid for describing nearly all trace metals, in particular toxic heavy metals like cadmium, mercury and lead. The frequency distribution of these metals has nearly the same asymmetry, although the one-way analysis of the variance shows that sample means come from different population means characterising the particular hatchery.

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The concentration of Cd, Hg and Pb in the soft part of mussels has been studied by means of bi- and multi-variate statistical approaches. In particular, the principal component analysis has been applied to study the association among these toxic metals in mussels sampled from the gulf of Trieste, which is a critical area as far as mercury pollution is concerned.

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A systematic study of vegetables and other agricultural products used as foods, was performed, in order to suggest a tentative classification of products exposed to roadside lead pollution from automobile exhausts. A hyperbolic two-parameter function is used as an empirical model to describe the decrease in lead content with the distance from the line source. Regression analysis of the linearized function allows the estimation of the parameters. Polluted products are classified by means of cluster analysis.

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Many studies have recently been devoted to the determination of lead and cadmium in milk, in view of the toxicity of these metals and the importance of milk in the diet of infants and children. Enrichment of lead and cadmium in fatty dairy products has been sometimes noted. A systematic study on milk and its primary products (skimmed milk, cream and cheese) obtained from the same batch of milk is considered in order to define a tentative balance of these two metals. Lead and cadmium were determined by atomic-absorption spectrophotometry with graphite furnace on a solution of the ashed sample. As a consequence of the appreciable interference due to the matrix effects, the method of standard additions was adopted to determine the metals in few samples with a statistically acceptable degree of accuracy and precision. The range of the lead and cadmium content found in these products is comparable with recent literature data concerning uncontaminated samples.

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