Meat, fish, coffee, tea, mushroom, and spices are foods that have been acknowledged for their nut... more Meat, fish, coffee, tea, mushroom, and spices are foods that have been acknowledged for their nutritional benefits but are also reportedly targets of fraud and tampering due to their economic value. Conventional methods often take precedence for monitoring these foods, but rapid advanced instruments employing molecular spectroscopic techniques are gradually claiming dominance due to their numerous advantages such as low cost, little to no sample preparation, and, above all, their ability to fingerprint and detect a deviation from quality. This review aims to provide a detailed overview of common molecular spectroscopic techniques and their use for agricultural and food quality management. Using multiple databases including ScienceDirect, Scopus, Web of Science, and Google Scholar, 171 research publications including research articles, review papers, and book chapters were thoroughly reviewed and discussed to highlight new trends, accomplishments, challenges, and benefits of using mo...
Coffee quality, and therefore its price, is determined by coffee species and varieties, geographi... more Coffee quality, and therefore its price, is determined by coffee species and varieties, geographic location, the method used to process green coffee beans, and particularly the care taken during coffee production. Determination of coffee quality is often done by the nondestructive and fast near infrared spectroscopy (NIRS), which provides a huge amount of data about the samples. NIRS data require sophisticated, multivariate data analysis methods, such as principal component analysis, or linear discriminant analysis. Since the obtained data are a set of spectra, they can also be analyzed by signal processing methods. In the present study, the applications of two novel methods, detrended fluctuation analysis (DFA) and yield stability index (YSI), is introduced on NIR spectra of different roasting levels of coffee samples. Fourteen green coffee samples from all over the world have been roasted on three different levels and their NIR spectra were analyzed. DFA successfully differentiate...
Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the gr... more Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the growing trend of snack consumption, it is more and more difficult to guarantee the quality and safety of the products. Near infrared spectroscopy (NIRS) method, combined with chemometric techniques provide outstanding solutions, due to its rapidity and simple sample preparation. The objective of this study was to investigate the possibilities of using NIRS to predict fat, protein, carbohydrate, sugar and salt content of all in all 155 commercially available snack products from 25 countries. The prediction models were performed using partial least squares regression (PLSR) with different spectral pre-processing methods. Different pre-processing methods proved to be the best to predict the five macronutrients, however, the final models showed good accuracy |R2/Q2 > 0.94/0.82|. The energy content of the samples was calculated from the measured parameters and interval PLS regression was accomplished to improve prediction parameters. The methods developed are suitable for analyzing snacks made from single or mixed raw materials.
Fourteen different Pleurotus ostreatus cultivars (Po_1–Po_14) were tested for free amino acid con... more Fourteen different Pleurotus ostreatus cultivars (Po_1–Po_14) were tested for free amino acid content (fAA), total polyphenol content (TPC), and antioxidant capacity (Ferric Reducing Ability of Plasma—FRAP) to select the cultivars with the most favorable traits. Automatic amino acid analyzer (fAA) and spectrophotometric assay (TPC, FRAP) results as well as Fourier-transform near infrared (FT-NIR) spectra were evaluated with different chemometric methods (Kruskal–Wallis test, Principal Component Analysis—PCA, Linear Discriminant Analysis—LDA). Based on total free amino acid concentrations and FRAP values, the Po_2 cultivar was found to be the most favorable. Types Po_3, Po_8, Po_10 and Po_12 were separated using PCA. Based on the spectral profile, they may contain polyphenols and reducing compounds of different qualities. LDA classification that was based on the concentrations of all free amino acids, cysteine, and proline of the cultivars was performed with an accuracy of over 90%. ...
Coffee quality, and therefore its price, is determined by coffee species and varieties, geographi... more Coffee quality, and therefore its price, is determined by coffee species and varieties, geographic location, the method used to process green coffee beans, and particularly the care taken during coffee production. Determination of coffee quality is often done by the nondestructive and fast near infrared spectroscopy (NIRS), which provides a huge amount of data about the samples. NIRS data require sophisticated, multivariate data analysis methods, such as principal component analysis, or linear discriminant analysis. Since the obtained data are a set of spectra, they can also be analyzed by signal processing methods. In the present study, the applications of two novel methods, detrended fluctuation analysis (DFA) and yield stability index (YSI), is introduced on NIR spectra of different roasting levels of coffee samples. Fourteen green coffee samples from all over the world have been roasted on three different levels and their NIR spectra were analyzed. DFA successfully differentiate...
Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the gr... more Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the growing trend of snack consumption, it is more and more difficult to guarantee the quality and safety of the products. Near infrared spectroscopy (NIRS) method, combined with chemometric techniques provide outstanding solutions, due to its rapidity and simple sample preparation. The objective of this study was to investigate the possibilities of using NIRS to predict fat, protein, carbohydrate, sugar and salt content of all in all 155 commercially available snack products from 25 countries. The prediction models were performed using partial least squares regression (PLSR) with different spectral pre-processing methods. Different pre-processing methods proved to be the best to predict the five macronutrients, however, the final models showed good accuracy |R2/Q2 > 0.94/0.82|. The energy content of the samples was calculated from the measured parameters and interval PLS regression was accomplished to improve prediction parameters. The methods developed are suitable for analyzing snacks made from single or mixed raw materials.
Fruit samples were analysed to investigate the suitability of Fourier transform near infrared spe... more Fruit samples were analysed to investigate the suitability of Fourier transform near infrared spectroscopy (FT-NIR) for the rapid discrimination of elderberry genotypes. Parallel analysis with classical chemical techniques and spectral measurements was performed on 11 cultivars originating from various European countries. The titratable acidity (TA) and soluble solids content (SSC) of the fruit, and the geographical origin and breeding method of the cultivar were used as reference data. Three spectrum transformation methods (standard normal variation, multiplicative scatter correction and first derivative) were applied in the calibration process. The statistical analysis and comparison of the samples was carried out using principal component analysis (PCA) and linear discriminant analysis (LDA). In all cases the analysis demonstrated a correlation between the spectra and both the chemical traits (TA and SSC) of the fruit and the other reference data, indicating that pattern recognit...
More than a hundred margarine samples and their FT-NIR spectra were used to develop regression mo... more More than a hundred margarine samples and their FT-NIR spectra were used to develop regression models, and to compare them with sum of ranking differences and ANOVA.
The antioxidant capacity assays are compared with principal component analysis and cluster analys... more The antioxidant capacity assays are compared with principal component analysis and cluster analysis. The best candidate to replace all of the other methods is selected using sum of ranking differences and the pair correlation method.
The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokin... more The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokinase (PFK) by means of both a heat inactivation and an auxiliary enzyme system were studied. It was found that both methods are suitable for measuring the inhibition of phosphofructokinase by metal ions. It was further found that metal ion concentrations causing 50% deactivation of PFK could not considerably influence the measuring capacity of the auxiliary enzyme system.
The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokin... more The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokinase (PFK) by means of both a heat inactivation and an auxiliary enzyme system were studied. It was found that both methods are suitable for measuring the inhibition of phosphofructokinase by metal ions. It was further found that metal ion concentrations causing 50% deactivation of PFK could not considerably influence the measuring capacity of the auxiliary enzyme system.
Meat, fish, coffee, tea, mushroom, and spices are foods that have been acknowledged for their nut... more Meat, fish, coffee, tea, mushroom, and spices are foods that have been acknowledged for their nutritional benefits but are also reportedly targets of fraud and tampering due to their economic value. Conventional methods often take precedence for monitoring these foods, but rapid advanced instruments employing molecular spectroscopic techniques are gradually claiming dominance due to their numerous advantages such as low cost, little to no sample preparation, and, above all, their ability to fingerprint and detect a deviation from quality. This review aims to provide a detailed overview of common molecular spectroscopic techniques and their use for agricultural and food quality management. Using multiple databases including ScienceDirect, Scopus, Web of Science, and Google Scholar, 171 research publications including research articles, review papers, and book chapters were thoroughly reviewed and discussed to highlight new trends, accomplishments, challenges, and benefits of using mo...
Coffee quality, and therefore its price, is determined by coffee species and varieties, geographi... more Coffee quality, and therefore its price, is determined by coffee species and varieties, geographic location, the method used to process green coffee beans, and particularly the care taken during coffee production. Determination of coffee quality is often done by the nondestructive and fast near infrared spectroscopy (NIRS), which provides a huge amount of data about the samples. NIRS data require sophisticated, multivariate data analysis methods, such as principal component analysis, or linear discriminant analysis. Since the obtained data are a set of spectra, they can also be analyzed by signal processing methods. In the present study, the applications of two novel methods, detrended fluctuation analysis (DFA) and yield stability index (YSI), is introduced on NIR spectra of different roasting levels of coffee samples. Fourteen green coffee samples from all over the world have been roasted on three different levels and their NIR spectra were analyzed. DFA successfully differentiate...
Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the gr... more Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the growing trend of snack consumption, it is more and more difficult to guarantee the quality and safety of the products. Near infrared spectroscopy (NIRS) method, combined with chemometric techniques provide outstanding solutions, due to its rapidity and simple sample preparation. The objective of this study was to investigate the possibilities of using NIRS to predict fat, protein, carbohydrate, sugar and salt content of all in all 155 commercially available snack products from 25 countries. The prediction models were performed using partial least squares regression (PLSR) with different spectral pre-processing methods. Different pre-processing methods proved to be the best to predict the five macronutrients, however, the final models showed good accuracy |R2/Q2 > 0.94/0.82|. The energy content of the samples was calculated from the measured parameters and interval PLS regression was accomplished to improve prediction parameters. The methods developed are suitable for analyzing snacks made from single or mixed raw materials.
Fourteen different Pleurotus ostreatus cultivars (Po_1–Po_14) were tested for free amino acid con... more Fourteen different Pleurotus ostreatus cultivars (Po_1–Po_14) were tested for free amino acid content (fAA), total polyphenol content (TPC), and antioxidant capacity (Ferric Reducing Ability of Plasma—FRAP) to select the cultivars with the most favorable traits. Automatic amino acid analyzer (fAA) and spectrophotometric assay (TPC, FRAP) results as well as Fourier-transform near infrared (FT-NIR) spectra were evaluated with different chemometric methods (Kruskal–Wallis test, Principal Component Analysis—PCA, Linear Discriminant Analysis—LDA). Based on total free amino acid concentrations and FRAP values, the Po_2 cultivar was found to be the most favorable. Types Po_3, Po_8, Po_10 and Po_12 were separated using PCA. Based on the spectral profile, they may contain polyphenols and reducing compounds of different qualities. LDA classification that was based on the concentrations of all free amino acids, cysteine, and proline of the cultivars was performed with an accuracy of over 90%. ...
Coffee quality, and therefore its price, is determined by coffee species and varieties, geographi... more Coffee quality, and therefore its price, is determined by coffee species and varieties, geographic location, the method used to process green coffee beans, and particularly the care taken during coffee production. Determination of coffee quality is often done by the nondestructive and fast near infrared spectroscopy (NIRS), which provides a huge amount of data about the samples. NIRS data require sophisticated, multivariate data analysis methods, such as principal component analysis, or linear discriminant analysis. Since the obtained data are a set of spectra, they can also be analyzed by signal processing methods. In the present study, the applications of two novel methods, detrended fluctuation analysis (DFA) and yield stability index (YSI), is introduced on NIR spectra of different roasting levels of coffee samples. Fourteen green coffee samples from all over the world have been roasted on three different levels and their NIR spectra were analyzed. DFA successfully differentiate...
Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the gr... more Abstract Nowadays, the consumption of snack products is permanently increasing. Because of the growing trend of snack consumption, it is more and more difficult to guarantee the quality and safety of the products. Near infrared spectroscopy (NIRS) method, combined with chemometric techniques provide outstanding solutions, due to its rapidity and simple sample preparation. The objective of this study was to investigate the possibilities of using NIRS to predict fat, protein, carbohydrate, sugar and salt content of all in all 155 commercially available snack products from 25 countries. The prediction models were performed using partial least squares regression (PLSR) with different spectral pre-processing methods. Different pre-processing methods proved to be the best to predict the five macronutrients, however, the final models showed good accuracy |R2/Q2 > 0.94/0.82|. The energy content of the samples was calculated from the measured parameters and interval PLS regression was accomplished to improve prediction parameters. The methods developed are suitable for analyzing snacks made from single or mixed raw materials.
Fruit samples were analysed to investigate the suitability of Fourier transform near infrared spe... more Fruit samples were analysed to investigate the suitability of Fourier transform near infrared spectroscopy (FT-NIR) for the rapid discrimination of elderberry genotypes. Parallel analysis with classical chemical techniques and spectral measurements was performed on 11 cultivars originating from various European countries. The titratable acidity (TA) and soluble solids content (SSC) of the fruit, and the geographical origin and breeding method of the cultivar were used as reference data. Three spectrum transformation methods (standard normal variation, multiplicative scatter correction and first derivative) were applied in the calibration process. The statistical analysis and comparison of the samples was carried out using principal component analysis (PCA) and linear discriminant analysis (LDA). In all cases the analysis demonstrated a correlation between the spectra and both the chemical traits (TA and SSC) of the fruit and the other reference data, indicating that pattern recognit...
More than a hundred margarine samples and their FT-NIR spectra were used to develop regression mo... more More than a hundred margarine samples and their FT-NIR spectra were used to develop regression models, and to compare them with sum of ranking differences and ANOVA.
The antioxidant capacity assays are compared with principal component analysis and cluster analys... more The antioxidant capacity assays are compared with principal component analysis and cluster analysis. The best candidate to replace all of the other methods is selected using sum of ranking differences and the pair correlation method.
The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokin... more The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokinase (PFK) by means of both a heat inactivation and an auxiliary enzyme system were studied. It was found that both methods are suitable for measuring the inhibition of phosphofructokinase by metal ions. It was further found that metal ion concentrations causing 50% deactivation of PFK could not considerably influence the measuring capacity of the auxiliary enzyme system.
The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokin... more The possibilities of exact measuring the effect of metal ions on the activity of phosphofructokinase (PFK) by means of both a heat inactivation and an auxiliary enzyme system were studied. It was found that both methods are suitable for measuring the inhibition of phosphofructokinase by metal ions. It was further found that metal ion concentrations causing 50% deactivation of PFK could not considerably influence the measuring capacity of the auxiliary enzyme system.
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