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The aim of this paper was to study the fatty acid composition of total and "free" lipids in powdered infant milks and to evaluate the fatty acid oxidation after package opening. In its first step the application of Principal Component Analysis and Design of Experiments has allowed to take a comprehensive picture of powdered infant formulas on sale in Italy on the basis of their labelled composition and to select a limited number of representative samples. Both total and "non encapsulated" or "free" lipids were considered and analysed and no significant differences were found between their fatty acids contents. The possible modification of the fatty acid composition in the "free" lipids caused by oxidation was also studied, simulating the domestic habits after opening. No significant changes were observed up to 30 days even when formulas had an high content of unsaturated fatty acids and valuable Long Chain Polyunsaturated fatty acids.

‘Violet Nori’ is a new spontaneous growing violet rice variety showing a peculiar violet color in its fresh leaves as well. In this paper, the antioxidant properties and the content of total phenols, radical scavengers, and anthocyanins in ‘Violet Nori’ caryopses, flour, and leaves are explored and compared. Ultrasonic-Assisted Extraction (UAE) is employed for the extraction of phenolic compounds, improving the extraction conditions by Design of Experiments (DoE). The obtained results show that the Radical Scavenging Activities (RSAs), the Total Phenolic Contents (TPCs), and the anthocyanin amounts (1000–1500 μg/g, expressed as cyanidin-3-glucoside) of ‘Violet Nori’ caryopses are higher than those in the other analyzed colored rice samples (300–900 μg/g as cyanidin-3-glucoside), with the exception of the cultivars ‘Artemide’ and ‘Nerone’, which show comparable values of RSAs and TPCs. The study of ‘Violet Nori’ leaves at different plant maturation stages shows that their anthocyanin content is 2–3 times higher than in the caryopses and in the flour, reaching the highest levels at about 60 days from seeding. Thus, the estimated extraction yield of 4 kg anthocyanins/t makes fresh leaves very interesting for the extraction of anthocyanins on an industrial scale, whereas violet caryopses are a very interesting dietetic source of valuable anthocyanins and other antioxidant compounds.

An authentication study of the Italian PDO (protected designation of origin) extra virgin olive oil Chianti Classico was performed; UV–visible (UV–vis), Near-Infrared (NIR) and Mid-Infrared (MIR) spectroscopies were applied to a set of samples representative of the whole Chianti Classico production area. The non-selective signals (fingerprints) provided by the three spectroscopic techniques were utilised both individually and jointly, after fusion of the respective profile vectors, in order to build a model for the Chianti Classico PDO olive oil. Moreover, these results were compared with those obtained by the gas chromatographic determination of the fatty acids composition. In order to characterise the olive oils produced in the Chianti Classico PDO area, UNEQ (unequal class models) and SIMCA (soft independent modelling of class analogy) were employed both on the MIR, NIR and UV–vis spectra, individually and jointly, and on the fatty acid composition. Finally, PLS (partial least square) regression was applied on the UV–vis, NIR and MIR spectra, in order to predict the content of oleic and linoleic acids in the extra virgin olive oils. UNEQ, SIMCA and PLS were performed after selection of the relevant predictors, in order to increase the efficiency of both classification and regression models. The non-selective information obtained from UV–vis, NIR and MIR spectroscopy allowed to build reliable models for checking the authenticity of the Italian PDO extra virgin olive oil Chianti Classico .

Headspace sorptive extraction and GC/MS, coupled with chemometric tools, were used to predict the amounts of pine nuts and Pecorino in Pesto Genovese, a typical Italian basil-based pasta sauce. Two groups of samples were prepared at different times and with ingredients from different batches for building the predicting models and testing their performances. Principal component analysis and partial least-squares regression (PLS) were applied to the chromatographic data. The 24 most-predictive variables were selected, and the application of PLS to the training set samples led to two models that explained approximately 70 of the variance in cross-validation, with prediction errors of 0.1 g for Pecorino and 0.6 g for pine nuts, thus confirming the reliability of the analytical method and the predicting ability of the models. The results obtained for the test set samples were not completely satisfactory, with a prediction error and a bias of 5.0 and 4.1 g, respectively, for Pecorino and corresponding values of 4.1 and 2.0 g for pine nuts. This preliminary study shows that the analytical methods used can allow construction of models with high predictive ability only if the great variability of the headspace composition of the ingredients and the effect of Twister are considered.

This paper describes the development and application of a new analytical method for the analysis of the volatile fractions of pesto , a typical Italian basil-based pasta sauce, and its ingredients. The extraction of the volatile fraction was realized by headspace sorptive extraction (HSSE) and the extracted volatiles were then thermodesorbed, cryoconcentrated in a cooled injector and analysed by gas chromatography-mass spectrometry. This study shows that despite the great variability detected in the composition of the volatile fractions of several samples of “Pesto Genovese”, the ingredients traditionally used in pesto preparation (basil, pine nuts, walnuts, cheese, extra-virgin olive oil and garlic) give a significant and distinctive contribution to the pesto volatile fraction. Thus, the HSSE analysis of “Pesto Genovese” could be very useful for a careful control of the composition of this valuable niche product.

Cholesterol oxidation in commercial meat-based homogenized and freeze-dried baby foods was examined. The 7 major products of this reaction were determined by gas chromatography coupled with mass spectrometry (GC-MS). As far as single cholesterol oxidation products (COP) are concerned, 7-ketocholesterol was the major product of direct cholesterol oxidation in the 2 groups of analyzed samples, and this study confirmed that it is a useful marker of the whole cholesterol oxidation process. Nevertheless, the amounts of cholesterol-5β,6β-epoxide were often similar to and sometimes higher than the amounts of 7-ketocholesterol, thus showing a strong development of both direct and indirect cholesterol oxidation pathways. Total COP content was significantly higher in freeze-dried than in homogenized products. Moreover, in freeze-dried samples, the COP content per serving was quite variable and, in 2 samples, it was close to or even higher than 500 μg. The greater development of cholesterol oxidation in the freeze-dried samples was confirmed by their highest total COP/cholesterol percent ratios. A constant correlation between the fatty acid composition and the development of cholesterol oxidation was not found, although a positive correlation between unsaturated fatty acid content and total COP content occasionally exists in samples of the same brand.

A new analytical method for fatty acid alkyl esters (FAAEs) determination by GC-MS in virgin olive oils is proposed. No sample preparation is required and FAAEs are directly thermo-desorbed and cryo-focalised in the cooled injector of a GC-MS (EI) instrument. The analytical conditions were optimized by Design of Experiment (DoE) techniques (an exploratory Plackett-Burman design followed by a factorial design on three selected variables). After the improvement of method performances, several samples of extra virgin and low quality virgin olive oils were analyzed both by the new method and by the Official EU Method of analysis. The application of Principal Component Analysis to the obtained results confirmed that the ability of the proposed method to discriminate between extra virgin and lower quality olive oils is at least equal to that of the Official Method, but the new method is faster, simpler, requires a much lower amount of organic solvents and significantly enhances method repeatability.

Two methods for routine analysis of free 7-ketocholesterol (7-k) in foods by high-performance liquid chromatography (HPLC) were compared. The analyzed samples were egg noodles, biscuits prepared with eggs, sweet snacks, grated Parmesan cheeses, and some ingredients utilized in the food industry (whole-milk and whole-egg powder). The enrichment of cholesterol oxides was carried out by solid-phase separation of the total lipids with florisil and silica cartridges for methods A and B, respectively. The 7-k analyses were run in normal-phase HPLC for method A, and a reverse-phase process was used in method B. Identification of the 7-k peak was confirmed by gas chromatography/mass spectrometry analysis and peak purity checkvia spectral analysis with a diode array detector. The quantitation of 7-k was carried out with an internal standard for method A and with a calibration curve for method B. The limit of quantitation (LQ) was 3 × 10−9 g/injection; the limit of detection was ten times lower than the LQ for both methods. The two methods showed good recovery (99%) and good repeatability (coefficient of variation of 3.9 and 3.7% for methods A and B, respectively). These methods allow a fast, sensitive, and reliable determination of one cholesterol oxidation product, which is present at a high concentration level in the first stages of the oxidation process.

Consumer demand for pomegranate juice has considerably grown, during the last years, for its potential health benefits. Since it is an expensive functional food, cheaper fruit juices addition (i.e., grape and apple juices) or its simple dilution, or polyphenols subtraction are deceptively used. At present, time-consuming analyses are used to control the quality of this product. Furthermore these analyses are expensive and require well-trained analysts. Thus, the purpose of this study was to propose a high-speed and easy-to-use shortcut. Based on UV–VIS spectroscopy and chemometrics, a screening method is proposed to quickly screening some common fillers of pomegranate juice that could decrease the antiradical scavenging capacity of pure products. The analytical method was applied to laboratory prepared juices, to commercial juices and to representative experimental mixtures at different levels of water and filler juices. The outcomes were evaluated by means of multivariate exploratory analysis. The results indicate that the proposed strategy can be a useful screening tool to assess addition of filler juices and water to pomegranate juices.

NIR spectroscopy is proposed as a rapid and effective analytical method for the identification of the cultivar of table olives. The study was particularly focused on the Taggiasca cultivar. A set of 46 samples representative of the Taggiasca production area was analysed together with 43 samples of table olives of different cultivars. After feature selection, LDA and SIMCA were applied to the NIR data as classification and class-modelling techniques, respectively. The excellent results obtained by NIR spectroscopy (mean specificity of the models 82.0%, sensibility >90%) were then compared to those obtained by the gas chromatographic (GC) determination of the fatty acids composition of the oils extracted from the samples of table olives. Finally, in order to test the potential synergy among different sources of information, the employed NIR and chemical variables were joined, but only a small improvement of the results obtained by NIR alone was reached.

The volatile fraction of different kinds of Pesto genovese, a typical Italian basil-based pasta sauce, was analysed by Headspace Sorptive Extraction (HSSE)-Gas Chromatography–Mass Spectrometry (GC–MS) coupled with chemometric methods. Three kinds of commercial samples were considered: (a) non heat-processed shop manufactured, (b) heat-processed industrial and (c) non heat-processed industrial samples. The category of heat-processed samples was easily discriminated by the amounts of the terpene hydrocarbon α-terpinene. In order to distinguish the three categories, multivariate statistical analysis was then performed. Good prediction results were obtained by the combination of Linear Discriminant Analysis (LDA) and Stepwise LDA (STEPLDA): the percentage of correct predictions was 92 for food industry manufactured non heat-processed samples and 100 both for shop manufactured, non heat-processed samples, and for food industry manufactured, heat-processed samples.

This study aimed at evaluating if the volatile terpenoid hydrocarbons of extravirgin olive oils from West Liguria, a North Italy region, could trace their geographical origin. If terpenoid hydrocarbons were individually considered, three compounds, i.e. alpha-copaene, alpha-muurolene and alpha-farnesene, allowed building a simple decision tree and discriminating oils produced in West Liguria from oils produced in other Mediterranean regions. Moreover, the multivariate analysis allowed building West Liguria class-models with high predictive ability, confirming the fundamental role of the volatile terpenoid hydrocarbons for the geographical characterisation of West Liguria oils.

Sterol oxidation was evaluated in commercial meat- and fish-based homogenized baby foods containing vegetable oil. Gas chromatography coupled with mass spectrometry (GC/MS) was used for the analytical determination of 7-ketocholesterol and 7-ketositosterol, which were chosen as markers of sterol oxidation in lipids of animal origin and vegetable origin, respectively. Cholestanetriol was also quantified, because its negative effects on atherogenesis and other biological processes are well known. In meat-based samplesg/serving. The 7-ketocholesterol and 7-ketositosterol were 2289 and 1140 g/serving, respectively, whereas the 7-ketocholesterol/cholesterol percent ratio was and 11-40 g/serving, respectively, whereas the cholestanetriol levels were 738 g/serving. The 7-ketocholesterol/cholesterol percent ratio was characteristic of each kind of meat and related to the levels of unsaturated fatty acids of animal lipids. In fish-based samples, the cholestanetriol and 7-ketocholesterol levels per serving were significantly lower than in meat samples, but in fish fillets they were about 2025, instead of 40, of the ingredients. The values of the 7-ketocholesterol/ cholesterol percent ratio in fish-based products were close to the values computed for chicken or turkey-based products. The detected values of cholestanetriol showed that the addition of vegetable oil enhances the development of the indirect bimolecular pathway of cholesterol oxidation, which was even more favorable in fish-based products.