Personal information environment awareness in the Czech Republic

This article discusses the condition of information and communication technology usage in relation to problematics of the personal information environment in the Czech Republic. As to start any broader study of this topic in the ara of the Czech Republic, it is necessary to assess a current perception of the personal information environment and its elements. As existing studies are aimed mainly at a technical point of view, the presented study is focused on user participation a perception of individual technology elements. By a mean of the survey, a data were collected and analyzed using cluster analysis. Established groups of users are presented. The results of this study may create the suitable basis for a further research of discussed phenomena in the Czech Republic as well as an element of comparison for similar studies in other countries. © 2018 The Authors, published by EDP Sciences

Security implications of the personal information environment

This article discusses a security in a background of the personal information environment. A role and importance of personal information environment and its security is on the rise due to the increasing inclusion of information and communication technology. In many cases, the focus of conducted studies is on the technological part of the problem. In this article, results of the user-oriented study are presented. The main aim was to establish how users perceive security applications. As a preliminary study, a method of survey was utilized. Gathered data were evaluated using common statistical methods. Results of the study are presented in a suitable form with a consideration of a large variety of answers between users. Results show areas of technology and user disagreements. These established differences will be used as a basis of the future research. © 2018 The Authors, published by EDP Sciences

Risk Minimisation during Food Preservation

Potraviny s prodlouženou údržností mají při stravování obyvatelstva za mimořádných událostí a krizových situací své významné a nezastupitelné místo. Většinou se uplatňují následně po kompletovaných nouzových potravinových dávkách. Při výrobě takovýchto potravin se uplatňuje řada specifických fyzikálněchemických procesů, které v konečném důsledku rozhodují o jejich kvalitě a bezpečnosti pro konzumenta. Správné zvládnutí a kontrola technologických procesů jsou pak nezbytnými předpoklady úspěšného dosažení zamýšlených vlastností a užitné hodnoty takovýchto finálních produktů. V příspěvku, který byl prezentován na konferenci ExFoS 2020 v Brně, jsou rozebrány některé základní aspekty, které se na vlastnostech uvedených potravin podílí.Foods with an extended shelf-life play an important and irreplaceable role in the diet of the population in emergencies and crisis situations. They are usually applied after complete emergency food rations. In the production of such foods, a number of specific physicochemical processes are applied, which ultimately determine their quality and safety for the consumer. The most used preservation methods are described here, which are applied to food intended for emergency catering of the population and rescue teams. Appropriate management and control of technological processes are then necessary prerequisites for the successful achievement of the intended properties and utility value of such final products. The paper, which was presented at the ExFoS 2020 conference in Brno, discusses some of the basic aspects that contribute to the features of these foods

The importance of higher alcohols and esters for sensory evaluation of Rheinriesling and Chardonnay wine varieties

For a consumer, one of the first characters for evaluation of wine is its scent. A pleasant aroma of wine associated with the subsequent taste experience can be remembered by the consumer for a long time and appreciated appropriately. For this reason, the aromatic properties of wine are very important to both consumers and producers. The question, however, is to assess the evaluation of wine sensory evaluation based on a rapidly developing chemical analysis without the use of a panel of evaluators. This study has dealt with the problem of the correlation of sensory evaluation of wine with the total content of higher alcohols and esters in wine prepared from the same wine varieties (Rheinriesling and Chardonnay) on the same vineyard under the same climatic conditions and processed using the same production technology in the years 2008 - 2012. The total content of higher alcohols and esters was determined by gas chromatography with a mass spectrometer (GC/MS). The correlation between the sensory evaluation and the total content of higher alcohols has not been established. However, the direct effect of the total content of the esters on the level of the sensory analysis of the two varieties studied was demonstrated. This can be an important economic indicator for a manufacturer who can estimate the sensory quality of the wine only on the basis of chemical analysis and thus estimate the success of the wine on the consumer market. © 2018 Potravinarstvo Slovak Journal of Food Sciences

Liquid chromatographic determination of polyphenenols in Czech beers during brewing proces

High performance liquid chromatographic (HPLC/UV) method was adapted for simultaneous determination of seven polyphenols, including derivatives of benzoic (gallic and vanillic acids) and cinnamic acids (p-coumaric, ferulic and sinapic acids), flavan-3-ols (catechin) and flavonols (rutin) in worts and beers at the various stages of the brewing process. Based on the semi-quantitative HPLC analysis, total polyphenols chromatographic index (TPCI) was in the ranges of 5.18 - 19.4 mg/L and 7.37 - 20.7 mg/L for all worts and beers, respectively. The HPLC analyses showed that relatively high levels of (+)-catechin and gallic acid were in all the worts and the beers, while the values were much lower for ferulic acid, rutin, vanillic acid, sinapic acid and p-coumaric acid. Polyphenols with relatively high concentrations, that were detected in all tested worts and beers, were gallic acid (1.29 - 4.75 mg/L resp. 2.59 - 4.97 mg/L), (+)-catechin (1.66 - 7.95 mg/L resp. 4.70 - 10.0 mg/L) and ferulic acid (0.41 - 4.53 mg/L resp. 1.05 - 2.87 mg/L). On the other side, the sinapic acid (0.72 - 1.59 mg/L resp. 0.72 - 2.5 mg/L), rutin (1.17 - 2.03 mg/L resp. 1.16 - 2.85 mg/L), p-coumaric acid (ND - 4.73 mg/L resp. ND - 1.44 mg/L) and vanillic acid (ND - 1.52 mg/L resp. 0.75 - 1.81 mg/L) were detected in lowest concentrations. In both, worts and beers investigated in this study, the changes in the contents of individual polyphenols were not uniform. In the case of some polyphenols, a decrease in the content was observed after boiling the worts with hops or after the main fermentation until maturation and filtration, but with some polyphenols, the concentrations were constant until the end of the process or even increased. © 2015 Potravinarstvo. All rights reserved

The importance of higher alcohols and esters for sensory evaluation of rheinriesling and chardonnay wine varieties

For a consumer, one of the first characters for evaluation of wine is its scent. A pleasant aroma of wine associated with the subsequent taste experience can be remembered by the consumer for a long time and appreciated appropriately. For this reason, the aromatic properties of wine are very important to both consumers and producers. The question, however, is to assess the evaluation of wine sensory evaluation based on a rapidly developing chemical analysis without the use of a panel of evaluators. This study has dealt with the problem of the correlation of sensory evaluation of wine with the total content of higher alcohols and esters in wine prepared from the same wine varieties (Rheinriesling and Chardonnay) on the same vineyard under the same climatic conditions and processed using the same production technology in the years 2008 - 2012. The total content of higher alcohols and esters was determined by gas chromatography with a mass spectrometer (GC/MS). The correlation between the sensory evaluation and the total content of higher alcohols has not been established. However, the direct effect of the total content of the esters on the level of the sensory analysis of the two varieties studied was demonstrated. This can be an important economic indicator for a manufacturer who can estimate the sensory quality of the wine only on the basis of chemical analysis and thus estimate the success of the wine on the consumer market. Normal 0 21 false false false EN-GB X-NONE X-NONE <w:LsdException Locked="false" Priority="71" Name="Colorful

SONDEO ARQUEOLÓGICO SECTOR 35 [Material gráfico]

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 201

Content of 4(5)-methylimidazole, caffeine and chlorogenic acid in commercial coffee brands

Content of 4(5)-methylimidazole (4-MeI), caffeine and chlorogenic acid in commercial coffee brands were determined using high-performance liquid chromatography (HPLC) with UV DAD and MS detectors. Positive ion ESI mass spectra of the 4-MeI standard yielded intense signals corresponding to [M+H]+ (83.0604) and [2M+H]+ ions (165.1115). Also, adducts of 4-MeI with acetonitrile from mobile were detected - [M+ACN]+ ions (124.0849). The LOD of 2.5 ng mL-1 and LOQ of 8.4 ng.mL-1 were calculated according to the following formulas: LOD = 3.SD/S, and LOQ = 10.SD/S, where S is the slope of the calibration curve and SD is the standard deviation of the noise. The caffeine content was compared to the results of the standard addition, 1st derivative and liquid-liquid extraction spectrophotometry. 4-MeI was in tens μg g-1 in the Vietnamese coffees while in units μg.g-1 in all Czech and Brazilian coffees (&lt;2.4 μg.g-1 and &lt;4.9 μg.g-1, respectively). The results for caffeine were within the documented range (0.31 - 2.20%) in all coffee samples. The lower content of caffeine and chlorogenic acid was observed in Vietnamese coffees. All the methods used for determination of caffeine in the Czech and Brazilian coffees gave acceptable precision and accuracy. However, there were significant differences in the results in Vietnamese coffees. The caffeine extractability (100 °C, 3 min brewing) almost reached 100% in Czech and Brazilian coffees, while it was less than 90% in Vietnamese coffees. The Czech and Brazilian coffees tend to produce more caffeine in brews than the Vietnamese coffee because of the different composition of blends and the particle size degree. © 2015 Potravinarstvo