In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technologica...In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technological stages of the wine. The consecutive, parallel and spontaneous development of several redox processes and their impact on the quality, microbiological and crystalline stability of white wines were examined. The reduction of additive and subtractive technological interventions, of the amounts of adjuvants (sulphurous anhydride) is essential for the production of organic wines.展开更多
The aim of this work is mainly to determine the effect of the pedoclimatic conditions (“terroir”) on the phenolic composition of wine originated from three French red grape varieties Cabernet Sauvignon, Merlot and S...The aim of this work is mainly to determine the effect of the pedoclimatic conditions (“terroir”) on the phenolic composition of wine originated from three French red grape varieties Cabernet Sauvignon, Merlot and Syrah, cultivated in the region of Thessaloniki (Northern Greece);simultaneously a study of its evolution during aging in a stainless steel tank, in oak barrels of different origin and in bottles is conducted. Additionally, in this work, we try to compare the evolution of phenolic composition of wines during aging in French medium toast oak barrel and in American heavy toast oak barrel. For this reason, 20 red wine samples originated from this area were analyzed. The color markers were measured by UV-spectrometry, while the phenolic acids and catechin content of the wine samples and their evolution during aging were determine by UVis-High performance liquid chromatography. Significant differences detected among the three grape varieties regarding color parameters, total anthocyanins and some phenolic acids. The increase of the extraction time during vinification affected the amounts of phenolic acids, catechin, total phenolic index (TPI) and tannin content. Gallic acid and catechin were the most abundant phenolic compounds and their amounts, as well as the concentrations of several phenolic acids were significantly affected during the storage period. Finally, the phenolic composition and the amounts of phenolic acids did not appear to be affected by the origin of oak barrels.展开更多
Currently, the food industry, including the meat industry, is paying close attention to the use of natural additives as preservatives. From ancient times, the plants are used to treat various diseases, to produce perf...Currently, the food industry, including the meat industry, is paying close attention to the use of natural additives as preservatives. From ancient times, the plants are used to treat various diseases, to produce perfumes and as ingredients to improve the taste in food. This paper presents a bibliographic and experimental study of the antioxidant and microbial properties of basil, thyme and tarragon. International scientific papers on the use of these plants in the food industry, including the meat industry, are targeted. The role of basil, thyme and tarragon in the manufacture of functional and stable products in storage is mentioned. Percentage decrease in <i>Salmonella Abony</i> growth under the influence of basil constituted 84.4%, thyme 61.6% and tarragon 76.8% after 48 hours of action and respectively 97.2%, 90.2% and 95.3% after 72 hours of action. The interdependence between the percentage reduction of S. Abony infestation and the concentration of basil, mushrooms and tarragon was respectively: basil (R<sup>2</sup> = 0.7725 … 0.7916), thyme (R<sup>2</sup> = 0.7733 … 0.7768), tarragon (R<sup>2</sup> = 0.7689 … 0.8137).展开更多
This article focuses on the mathematical modelling of the extraction process of bioactive compounds from grape marc and berries (Aronia, rosehip, rowan, and hawthorn). The composition of the extraction medium (the con...This article focuses on the mathematical modelling of the extraction process of bioactive compounds from grape marc and berries (Aronia, rosehip, rowan, and hawthorn). The composition of the extraction medium (the concentration of the ethyl alcohol) served as a factor of influence. Furthermore, 8 experimental measured parameters were used as variables. The experimental results were processed using Hermite polynomials. In order to adapt the degree of the polynomial, the following conditions were imposed: high precision of the mathematical model by appealing to models on interval;obtaining a nominal model and two uncertain models (upper and lower);deduction of two predictive models, one superior and one inferior. It was found that the mathematical models based on Hermite polynomials do not provide explicit analytical expressions, although they allow the establishment of parameter values for any concentration of the extraction medium. In some cases, only high-grade polynomial models ensure the modelling error below 2%. Uncertain models (upper and lower 95%) include all experimental data. Predictive mathematical models (upper and lower) were established for a high prediction. The analytical expressions of the mathematical models on intervals are non-gaps, the coefficients having non-zero values. Dependencies between the measured parameters and the composition of the extraction solvent were analyzed, the results being presented through the calculation of a surface, with all the experimental values and their average values. Thus, it was found that polynomial mathematical models provide complete information for modelling the extraction processes of bioactive compounds of plant origin.展开更多
The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine mater...The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine material of red grape variety "Saperavi". After completion of malolactic fermentation, the second racking the wine material off the lees and its treatment with antiseptics were carried out. Sulfur dioxide (Kadifit) and different doses of nanostructured silver were used. Microbiological investigation was performed on the presence of lactic bacteria after completion of malolactic fermentation and racking off the lees. The investigation of phenolic compounds was conducted at the following stages of technological processes: (1) after completion of alcoholic fermentation and racking off the lees; (2) after completion of malolactic fermentation; (3) after the second racking off the lees and treatment with antiseptics. By means of the HPLC analysis, the amounts ofcatechins, phenolcarbonic acids and flavonols were determined. It has been established that after conduction of malolactic fermentation in the process of racking the wine material off the lees and storage, the application of 0.6 mg/L of nano-silver for blocking of lactic-acid bacteria and inhibition of oxidation of phenolic compounds has the same effect as sulfitization with 50 mg/L of Kadifit.展开更多
<i>Fusarium sp.</i> and mycotoxins of these species pose a major risk to consumer health, agriculture and the food industry. This paper is a worldwide bibliographic study on impact of <i>Fusarium<...<i>Fusarium sp.</i> and mycotoxins of these species pose a major risk to consumer health, agriculture and the food industry. This paper is a worldwide bibliographic study on impact of <i>Fusarium</i> and mycotoxins on the food chain. The factors influencing the development of fungi <i>Fusarium sp.</i>, the formation of mycotoxins and their microbiological risk on the food chain must be considered as a whole. For cereals and oilseeds before and after harvest, fungal infections and mycotoxin contamination present serious problems worldwide. This paper is an overview of the factors that include the microbiological risk and impact of <i>Fusarium</i> in the food chain mentioned in national and international studies. The methods and results obtained in this direction internationally are mentioned, such as: infrared spectroscopy, Raman spectrometry and hyperspectral imaging. Also, in review are presented solutions to reduce this impact on the food chain.展开更多
The article examines the application of correlation analysis of experimental data in research into the process of extracting bioactive compounds and antioxidant activity in plant extracts from berries and grape pomace...The article examines the application of correlation analysis of experimental data in research into the process of extracting bioactive compounds and antioxidant activity in plant extracts from berries and grape pomace. The correlation analysis of the experimental data allowed the establishment of the second order statistical characteristics (autocorrelation function, intercorrelation function and correlation coefficient). Based on the correlation analysis of the experimental data, it was shown that the influencing factor and the measured parameters have zero correlation coefficients for all types of researched extracts. This indicates that they are not independent. Therefore, related mathematical models can be deduced.展开更多
文摘In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technological stages of the wine. The consecutive, parallel and spontaneous development of several redox processes and their impact on the quality, microbiological and crystalline stability of white wines were examined. The reduction of additive and subtractive technological interventions, of the amounts of adjuvants (sulphurous anhydride) is essential for the production of organic wines.
文摘The aim of this work is mainly to determine the effect of the pedoclimatic conditions (“terroir”) on the phenolic composition of wine originated from three French red grape varieties Cabernet Sauvignon, Merlot and Syrah, cultivated in the region of Thessaloniki (Northern Greece);simultaneously a study of its evolution during aging in a stainless steel tank, in oak barrels of different origin and in bottles is conducted. Additionally, in this work, we try to compare the evolution of phenolic composition of wines during aging in French medium toast oak barrel and in American heavy toast oak barrel. For this reason, 20 red wine samples originated from this area were analyzed. The color markers were measured by UV-spectrometry, while the phenolic acids and catechin content of the wine samples and their evolution during aging were determine by UVis-High performance liquid chromatography. Significant differences detected among the three grape varieties regarding color parameters, total anthocyanins and some phenolic acids. The increase of the extraction time during vinification affected the amounts of phenolic acids, catechin, total phenolic index (TPI) and tannin content. Gallic acid and catechin were the most abundant phenolic compounds and their amounts, as well as the concentrations of several phenolic acids were significantly affected during the storage period. Finally, the phenolic composition and the amounts of phenolic acids did not appear to be affected by the origin of oak barrels.
文摘Currently, the food industry, including the meat industry, is paying close attention to the use of natural additives as preservatives. From ancient times, the plants are used to treat various diseases, to produce perfumes and as ingredients to improve the taste in food. This paper presents a bibliographic and experimental study of the antioxidant and microbial properties of basil, thyme and tarragon. International scientific papers on the use of these plants in the food industry, including the meat industry, are targeted. The role of basil, thyme and tarragon in the manufacture of functional and stable products in storage is mentioned. Percentage decrease in <i>Salmonella Abony</i> growth under the influence of basil constituted 84.4%, thyme 61.6% and tarragon 76.8% after 48 hours of action and respectively 97.2%, 90.2% and 95.3% after 72 hours of action. The interdependence between the percentage reduction of S. Abony infestation and the concentration of basil, mushrooms and tarragon was respectively: basil (R<sup>2</sup> = 0.7725 … 0.7916), thyme (R<sup>2</sup> = 0.7733 … 0.7768), tarragon (R<sup>2</sup> = 0.7689 … 0.8137).
文摘This article focuses on the mathematical modelling of the extraction process of bioactive compounds from grape marc and berries (Aronia, rosehip, rowan, and hawthorn). The composition of the extraction medium (the concentration of the ethyl alcohol) served as a factor of influence. Furthermore, 8 experimental measured parameters were used as variables. The experimental results were processed using Hermite polynomials. In order to adapt the degree of the polynomial, the following conditions were imposed: high precision of the mathematical model by appealing to models on interval;obtaining a nominal model and two uncertain models (upper and lower);deduction of two predictive models, one superior and one inferior. It was found that the mathematical models based on Hermite polynomials do not provide explicit analytical expressions, although they allow the establishment of parameter values for any concentration of the extraction medium. In some cases, only high-grade polynomial models ensure the modelling error below 2%. Uncertain models (upper and lower 95%) include all experimental data. Predictive mathematical models (upper and lower) were established for a high prediction. The analytical expressions of the mathematical models on intervals are non-gaps, the coefficients having non-zero values. Dependencies between the measured parameters and the composition of the extraction solvent were analyzed, the results being presented through the calculation of a surface, with all the experimental values and their average values. Thus, it was found that polynomial mathematical models provide complete information for modelling the extraction processes of bioactive compounds of plant origin.
文摘The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine material of red grape variety "Saperavi". After completion of malolactic fermentation, the second racking the wine material off the lees and its treatment with antiseptics were carried out. Sulfur dioxide (Kadifit) and different doses of nanostructured silver were used. Microbiological investigation was performed on the presence of lactic bacteria after completion of malolactic fermentation and racking off the lees. The investigation of phenolic compounds was conducted at the following stages of technological processes: (1) after completion of alcoholic fermentation and racking off the lees; (2) after completion of malolactic fermentation; (3) after the second racking off the lees and treatment with antiseptics. By means of the HPLC analysis, the amounts ofcatechins, phenolcarbonic acids and flavonols were determined. It has been established that after conduction of malolactic fermentation in the process of racking the wine material off the lees and storage, the application of 0.6 mg/L of nano-silver for blocking of lactic-acid bacteria and inhibition of oxidation of phenolic compounds has the same effect as sulfitization with 50 mg/L of Kadifit.
文摘<i>Fusarium sp.</i> and mycotoxins of these species pose a major risk to consumer health, agriculture and the food industry. This paper is a worldwide bibliographic study on impact of <i>Fusarium</i> and mycotoxins on the food chain. The factors influencing the development of fungi <i>Fusarium sp.</i>, the formation of mycotoxins and their microbiological risk on the food chain must be considered as a whole. For cereals and oilseeds before and after harvest, fungal infections and mycotoxin contamination present serious problems worldwide. This paper is an overview of the factors that include the microbiological risk and impact of <i>Fusarium</i> in the food chain mentioned in national and international studies. The methods and results obtained in this direction internationally are mentioned, such as: infrared spectroscopy, Raman spectrometry and hyperspectral imaging. Also, in review are presented solutions to reduce this impact on the food chain.
文摘The article examines the application of correlation analysis of experimental data in research into the process of extracting bioactive compounds and antioxidant activity in plant extracts from berries and grape pomace. The correlation analysis of the experimental data allowed the establishment of the second order statistical characteristics (autocorrelation function, intercorrelation function and correlation coefficient). Based on the correlation analysis of the experimental data, it was shown that the influencing factor and the measured parameters have zero correlation coefficients for all types of researched extracts. This indicates that they are not independent. Therefore, related mathematical models can be deduced.