Over the past 30 years, there has been an emphasis on the quality, safety and nutritional proprie... more Over the past 30 years, there has been an emphasis on the quality, safety and nutritional proprieties of food products and thus an increasing interest by food producers to reveal frauds and to assure consumers regarding the quality and provenance of their products.
Lichens are used as biomonitors of air pollution because they are extremely sensitive to the pres... more Lichens are used as biomonitors of air pollution because they are extremely sensitive to the presence of substances that alter atmospheric composition. Fifty-one thalli of two different varieties of Pseudevernia furfuracea (var. furfuracea and var. ceratea) were collected far from local sources of air pollution. Twenty-six of these thalli were then exposed to the air for one month in the industrial port of Genoa, which has high levels of environmental pollution. The possibility of using Near-infrared spectroscopy (NIRS) for generating a 'fingerprint' of lichens was investigated. Chemometric methods were successfully applied to discriminate between samples from polluted and non-polluted areas. In particular, Principal Component Analysis (PCA) was applied as a multivariate display method on the NIR spectra to visualise the data structure. This showed that the difference between samples of different varieties was not significant in comparison to the difference between samples e...
The possibility provided by Chemometrics to extract and combine (fusion) information contained in... more The possibility provided by Chemometrics to extract and combine (fusion) information contained in NIR and MIR spectra in order to discriminate monovarietal extra virgin olive oils according to olive cultivar (Casaliva, Leccino, Frantoio) has been investigated. Linear discriminant analysis (LDA) was applied as a classification technique on these multivariate and non-specific spectral data both separately and jointly (NIR and MIR data together). In order to ensure a more appropriate ratio between the number of objects (samples) and number of variables (absorbance at different wavenumbers), LDA was preceded either by feature selection or variable compression. For feature selection, the SELECT algorithm was used while a wavelet transform was applied for data compression. Correct classification rates obtained by cross-validation varied between 60% and 90% depending on the followed procedure. Most accurate results were obtained using the fused NIR and MIR data, with either feature selecti...
Introducció F a aproximadament uns cinquanta anys, es va iniciar la quimiometria. La figura 1 mos... more Introducció F a aproximadament uns cinquanta anys, es va iniciar la quimiometria. La figura 1 mostra un fragment de la carta que Bruce Kowalski i Svante Wold, els fundadors de la Chemometrics Society, van enviar als químics interessats en l'aplicació de mètodes matemàtics i estadístics a la química, tot convidant-los a formar part de la nova societat.
The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored a... more The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored as a tool to classify samples of Italian extra virgin olive oil on the basis of the cultivar.A total of 82 monovarietal samples (‘Casaliva’, ‘Leccino’ and ‘Frantoio’) of extra virgin olive oils were analysed. Several variables were measured: the free acidity, the peroxide value, spectrophotometric indices,
ABSTRACT In this work the effect of the addition of aqueous phenolic extracts, from olive and gra... more ABSTRACT In this work the effect of the addition of aqueous phenolic extracts, from olive and grape pomace, to fermentation media of the skim milk was investigated with the aim to produce a novel functional product. Additionally, Near Infrared (NIR) spectroscopy was assessed as a rapid and alternative method to traditional identification methods for the characterization of the new product. Results herein indicated that phenolic compounds are stable during the fermentation and they did not interfere with the manufacturing process. By extracting the information contained in the NIR spectra using the multivariate analysis, it was possible to discriminate between samples of probiotic milk according to the type of extract added and to evaluate the ‘stability’ of the product confirming NIR spectroscopy as a valid support to classical analysis. We concluded that, after sensorial evaluation of the product, fermented milk fortified with natural antioxidants could be considered a novel functional dairy product with health beneficial properties.
The identification of new biomarkers or a disease-related protein fingerprint for inflammatory bo... more The identification of new biomarkers or a disease-related protein fingerprint for inflammatory bowel diseases (IBDs) represents a major task in the diagnosis, prognosis and pharmacological therapy. To address these issues, a simple and rapid analytical proteomic method for serum protein profiling based on selective beads-based solid-phase bulk extraction, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and chemometric data analysis was developed. Serum proteins from healthy subjects (22) and patients with Crohn's disease (15) and ulcerative colitis (26) were selectively extracted according to reversed-phase (C18), strong anion-exchange (SAX) and metal ion affinity (IDA-Cu(II)) principles. This approach allowed enrichment of serum proteins/peptides due to the high interaction surface between analytes and the solid phase and high recovery due to the elution step performed directly on the MALDI-target plate. The MALDI-TOF MS serum protein profiles were acquired and, after a data pre-processing step, analyzed by linear discriminant analysis (LDA), a chemometric classification technique, in order to classify serum samples among healthy subjects and patients with inflammatory bowel diseases (IBDs). Since the high number of variables in the MALDI spectra (more than 16000 m/z values) prevents the use of LDA, the variables were reduced to 10-20 by features selection, thus allowing the evaluation of a pattern of m/z values with high discriminant power. Serum protein profiles obtained by reversed-phase extraction and the selection of 20 m/z values gave the best overall prediction ability (96.9%). The recognition of these m/z values may allow the identification of protein biomarkers involved in IBDs.
classification of extra virgin olive oils from Liguria, a region in northern Italy, according to ... more classification of extra virgin olive oils from Liguria, a region in northern Italy, according to their geographical origin. One hundred and ninety five olive oil samples were analysed using a near infrared (NIR) instrument and the recorded spectra were used to build a class model for Ligurian olive oil. Different class modelling techniques were used, i.e. potential functions techniques (POTFUN), soft independent modelling of class analogy (SIMCA), unequal-quadratic discriminant analysis (UNEQ-QDA) and multivariate range modelling (MRM). In order to remove systematic variation in experimental data such as base-line and multiplicative scatter effects, an evaluation of different data pre-processing methods was performed. Ligurian olive oil was clearly differentiated from the other oils and the multivariate analysis allowed the construction of Liguria class models with good predictive ability, high sensitivity and sufficient specificity. The results obtained suggest that NIR and chemometrics are useful tools in the geographic traceability of olive oil.
A fast head-space analysis instrument, constituted by an automatic sample introduction system dir... more A fast head-space analysis instrument, constituted by an automatic sample introduction system directly coupled to a mass detector without performing any chromatographic separation, was assembled. A suitable and original response was computed to optimise, by experimental design, the measured signals for discrimination purposes. The volatile fractions of 105 extra virgin olive oils coming from five different Mediterranean areas were analysed. The rough information collected by this system was unravelled and explained by well-known chemometrical techniques of display (principal component analysis), feature selection (stepwise linear discriminant analysis) and classification (linear discriminant analysis). The 93.4% of samples resulted to be correctly classified and the 90.5% correctly predicted by cross-validation procedure, whilst the 80.0% of an external test set, created to full validate the classification rule, were correctly assigned.
The volatile fraction of ninety-eight difrerent vinegars was analysed using a head-space analysis... more The volatile fraction of ninety-eight difrerent vinegars was analysed using a head-space analysis instrument assembled in our laboratory. This instrument is formed by an automatic sample introduction system, directly coupled to a mass detector without performing any chromatographic separation. The aim of this research was to classify the vinegar samples according to raw material (white or red wine, Sherry, malt, apple, alcohol) and production process (with or without ageing in wood barrels). The information contained in the measured signals was analysed by difrerent chemometrical techniqueb. Linear Discriminant Analysis was used as classification method, after applying a feature selection technique. The 100% of samples were correctly classified and predicted, by cross-validation procedure, according to raw material and according to the ageing process in wood barrels,
The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored a... more The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored as a tool to classify samples of Italian extra virgin olive oil on the basis of the cultivar. A total of 82 monovarietal samples ('Casaliva', 'Leccino' and 'Frantoio') of extra virgin olive oils were analysed. Several variables were measured: the free acidity, the peroxide value, spectrophotometric indices, the fatty acid composition, carotenoids, chlorophylls and tocopherol content. The same samples were also scanned by using NIR and MIR spectroscopy. The classification methods (LDA and SIMCA) were applied on chemical data and on the spectral data after having used the algorithm SELECT, as feature selection technique. The results showed that NIR and MIR spectroscopy is an interesting technique compared with traditional chemical index in classifying olive oil samples on the basis of the varietal origin. The spectroscopic methods could represent a reliable, cheap and fast classification tool, not requiring chemical analyses for discrimination among cultivars.
Over the past 30 years, there has been an emphasis on the quality, safety and nutritional proprie... more Over the past 30 years, there has been an emphasis on the quality, safety and nutritional proprieties of food products and thus an increasing interest by food producers to reveal frauds and to assure consumers regarding the quality and provenance of their products.
Lichens are used as biomonitors of air pollution because they are extremely sensitive to the pres... more Lichens are used as biomonitors of air pollution because they are extremely sensitive to the presence of substances that alter atmospheric composition. Fifty-one thalli of two different varieties of Pseudevernia furfuracea (var. furfuracea and var. ceratea) were collected far from local sources of air pollution. Twenty-six of these thalli were then exposed to the air for one month in the industrial port of Genoa, which has high levels of environmental pollution. The possibility of using Near-infrared spectroscopy (NIRS) for generating a 'fingerprint' of lichens was investigated. Chemometric methods were successfully applied to discriminate between samples from polluted and non-polluted areas. In particular, Principal Component Analysis (PCA) was applied as a multivariate display method on the NIR spectra to visualise the data structure. This showed that the difference between samples of different varieties was not significant in comparison to the difference between samples e...
The possibility provided by Chemometrics to extract and combine (fusion) information contained in... more The possibility provided by Chemometrics to extract and combine (fusion) information contained in NIR and MIR spectra in order to discriminate monovarietal extra virgin olive oils according to olive cultivar (Casaliva, Leccino, Frantoio) has been investigated. Linear discriminant analysis (LDA) was applied as a classification technique on these multivariate and non-specific spectral data both separately and jointly (NIR and MIR data together). In order to ensure a more appropriate ratio between the number of objects (samples) and number of variables (absorbance at different wavenumbers), LDA was preceded either by feature selection or variable compression. For feature selection, the SELECT algorithm was used while a wavelet transform was applied for data compression. Correct classification rates obtained by cross-validation varied between 60% and 90% depending on the followed procedure. Most accurate results were obtained using the fused NIR and MIR data, with either feature selecti...
Introducció F a aproximadament uns cinquanta anys, es va iniciar la quimiometria. La figura 1 mos... more Introducció F a aproximadament uns cinquanta anys, es va iniciar la quimiometria. La figura 1 mostra un fragment de la carta que Bruce Kowalski i Svante Wold, els fundadors de la Chemometrics Society, van enviar als químics interessats en l'aplicació de mètodes matemàtics i estadístics a la química, tot convidant-los a formar part de la nova societat.
The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored a... more The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored as a tool to classify samples of Italian extra virgin olive oil on the basis of the cultivar.A total of 82 monovarietal samples (‘Casaliva’, ‘Leccino’ and ‘Frantoio’) of extra virgin olive oils were analysed. Several variables were measured: the free acidity, the peroxide value, spectrophotometric indices,
ABSTRACT In this work the effect of the addition of aqueous phenolic extracts, from olive and gra... more ABSTRACT In this work the effect of the addition of aqueous phenolic extracts, from olive and grape pomace, to fermentation media of the skim milk was investigated with the aim to produce a novel functional product. Additionally, Near Infrared (NIR) spectroscopy was assessed as a rapid and alternative method to traditional identification methods for the characterization of the new product. Results herein indicated that phenolic compounds are stable during the fermentation and they did not interfere with the manufacturing process. By extracting the information contained in the NIR spectra using the multivariate analysis, it was possible to discriminate between samples of probiotic milk according to the type of extract added and to evaluate the ‘stability’ of the product confirming NIR spectroscopy as a valid support to classical analysis. We concluded that, after sensorial evaluation of the product, fermented milk fortified with natural antioxidants could be considered a novel functional dairy product with health beneficial properties.
The identification of new biomarkers or a disease-related protein fingerprint for inflammatory bo... more The identification of new biomarkers or a disease-related protein fingerprint for inflammatory bowel diseases (IBDs) represents a major task in the diagnosis, prognosis and pharmacological therapy. To address these issues, a simple and rapid analytical proteomic method for serum protein profiling based on selective beads-based solid-phase bulk extraction, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and chemometric data analysis was developed. Serum proteins from healthy subjects (22) and patients with Crohn's disease (15) and ulcerative colitis (26) were selectively extracted according to reversed-phase (C18), strong anion-exchange (SAX) and metal ion affinity (IDA-Cu(II)) principles. This approach allowed enrichment of serum proteins/peptides due to the high interaction surface between analytes and the solid phase and high recovery due to the elution step performed directly on the MALDI-target plate. The MALDI-TOF MS serum protein profiles were acquired and, after a data pre-processing step, analyzed by linear discriminant analysis (LDA), a chemometric classification technique, in order to classify serum samples among healthy subjects and patients with inflammatory bowel diseases (IBDs). Since the high number of variables in the MALDI spectra (more than 16000 m/z values) prevents the use of LDA, the variables were reduced to 10-20 by features selection, thus allowing the evaluation of a pattern of m/z values with high discriminant power. Serum protein profiles obtained by reversed-phase extraction and the selection of 20 m/z values gave the best overall prediction ability (96.9%). The recognition of these m/z values may allow the identification of protein biomarkers involved in IBDs.
classification of extra virgin olive oils from Liguria, a region in northern Italy, according to ... more classification of extra virgin olive oils from Liguria, a region in northern Italy, according to their geographical origin. One hundred and ninety five olive oil samples were analysed using a near infrared (NIR) instrument and the recorded spectra were used to build a class model for Ligurian olive oil. Different class modelling techniques were used, i.e. potential functions techniques (POTFUN), soft independent modelling of class analogy (SIMCA), unequal-quadratic discriminant analysis (UNEQ-QDA) and multivariate range modelling (MRM). In order to remove systematic variation in experimental data such as base-line and multiplicative scatter effects, an evaluation of different data pre-processing methods was performed. Ligurian olive oil was clearly differentiated from the other oils and the multivariate analysis allowed the construction of Liguria class models with good predictive ability, high sensitivity and sufficient specificity. The results obtained suggest that NIR and chemometrics are useful tools in the geographic traceability of olive oil.
A fast head-space analysis instrument, constituted by an automatic sample introduction system dir... more A fast head-space analysis instrument, constituted by an automatic sample introduction system directly coupled to a mass detector without performing any chromatographic separation, was assembled. A suitable and original response was computed to optimise, by experimental design, the measured signals for discrimination purposes. The volatile fractions of 105 extra virgin olive oils coming from five different Mediterranean areas were analysed. The rough information collected by this system was unravelled and explained by well-known chemometrical techniques of display (principal component analysis), feature selection (stepwise linear discriminant analysis) and classification (linear discriminant analysis). The 93.4% of samples resulted to be correctly classified and the 90.5% correctly predicted by cross-validation procedure, whilst the 80.0% of an external test set, created to full validate the classification rule, were correctly assigned.
The volatile fraction of ninety-eight difrerent vinegars was analysed using a head-space analysis... more The volatile fraction of ninety-eight difrerent vinegars was analysed using a head-space analysis instrument assembled in our laboratory. This instrument is formed by an automatic sample introduction system, directly coupled to a mass detector without performing any chromatographic separation. The aim of this research was to classify the vinegar samples according to raw material (white or red wine, Sherry, malt, apple, alcohol) and production process (with or without ageing in wood barrels). The information contained in the measured signals was analysed by difrerent chemometrical techniqueb. Linear Discriminant Analysis was used as classification method, after applying a feature selection technique. The 100% of samples were correctly classified and predicted, by cross-validation procedure, according to raw material and according to the ageing process in wood barrels,
The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored a... more The use of near and mid infrared spectroscopy, combined with chemometric analysis, was explored as a tool to classify samples of Italian extra virgin olive oil on the basis of the cultivar. A total of 82 monovarietal samples ('Casaliva', 'Leccino' and 'Frantoio') of extra virgin olive oils were analysed. Several variables were measured: the free acidity, the peroxide value, spectrophotometric indices, the fatty acid composition, carotenoids, chlorophylls and tocopherol content. The same samples were also scanned by using NIR and MIR spectroscopy. The classification methods (LDA and SIMCA) were applied on chemical data and on the spectral data after having used the algorithm SELECT, as feature selection technique. The results showed that NIR and MIR spectroscopy is an interesting technique compared with traditional chemical index in classifying olive oil samples on the basis of the varietal origin. The spectroscopic methods could represent a reliable, cheap and fast classification tool, not requiring chemical analyses for discrimination among cultivars.
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Papers by Monica Casale