Czech Journal of Food Sciences, 2009 (vol. 27), issue 6
Index of volume 27, Author index, Author institution index, List of reviewers, Subject indexIndex
editors
Czech J. Food Sci., 2009, 27(6):I-XXII | DOI: 10.17221/1373-CJFS 
Eggshell crack detection based on acoustic impulse response and supervised pattern recognition
Hao LIN, Jie-Wen ZHAO, Quan-Sheng CHEN, Jian-Rong CAI, Ping ZHOU
Czech J. Food Sci., 2009, 27(6):393-402 | DOI: 10.17221/82/2009-CJFS
A system based on acoustic resonance was developed for eggshell crack detection. It was achieved by the analysis of the measured frequency response of eggshell excited with a light mechanism. The response signal was processed by recursive least squares adaptive filter, which resulted in the signal-to-noise ratio of the acoustic impulse response reing remarkably enhanced. Five features variables were exacted from the response frequency signals. To develop a robust discrimination model, three pattern recognition algorithms (i.e. K-nearest neighbours, artificial neural network, and support vector machine) were examined comparatively in this work. Some...
Stability of quality traits in winter wheat cultivars
Daniela Mikulíková, Štefan Masár, Viera Horváthová, Ján Kraic
Czech J. Food Sci., 2009, 27(6):403-417 | DOI: 10.17221/96/2009-CJFS
We investigated the stability of 15 traits of quality in 45 winter wheat cultivars grown in two seasons in the Borovce locality of Slovakia. The gluten swelling, SDS test, starch content, α-amylase (α-AMS) activity, and volume weight were affected simultaneously by the cultivar, growing year, and the country of origin. Other traits were affected by only one or two of these factors. The English cultivars, when compared to the Slovak cultivars, demonstrated lower gluten swelling and volume weight, a higher α-AMS activity, and a longer vegetative period. We observed a higher α-AMS activity in the Czech, a lower starch content in...
Effects of location and year on technological quality and pentosan content in rye
Jindřiška Kučerová
Czech J. Food Sci., 2009, 27(6):418-424 | DOI: 10.17221/8/2009-CJFS
Four year trials were undertaken to study the milling and baking rye quality, the hybrid variety Picasso and population varieties Dankowskie nowe and Selgo having been examined coming from three different locations of the Czech Republic. The variety significantly (P < 0.01) influenced the specific weight, grain size, amylograph maximum, and grain yield. The year of harvest significantly (P < 0.01) influenced the thousand grain weight, maltose content, protein content, amylograph maximum, and grain yield. The location significantly (P < 0.01) influenced the thousand grain weight, protein content, amylograph maximum, and...
Total luminescence spectroscopy for differentiating between brandies and wine distillates
Jana Tóthová, Jana Sádecká, Pavel Májek
Czech J. Food Sci., 2009, 27(6):425-432 | DOI: 10.17221/125/2008-CJFS
In this study, the differentiation was investigated between brandy and wine distillate samples by fluorescence spectroscopy in combination with multivariate analysis. The samples corresponding to eight brandies from three producers and sixteen wine distillates from five producers were acquired in the local supermarkets. Total luminescence spectra of diluted and undiluted samples were recorded. In order to extract reliable information from the data sets, two multivariate analysis methods, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA), were applied separately on the excitation and emission spectra. The best differentiation...
Growth characterisation of Staphylococcus aureus in milk: a quantitative approach
Alžbeta Medveďová, Ľubomír Valík, Zuzana Sirotná, Denisa Liptáková
Czech J. Food Sci., 2009, 27(6):433-453 | DOI: 10.17221/24/2009-CJFS
Staphylococcus aureus is a pathogenic bacterium that induces several of human illnesses. The staphylococcal enterotoxin (SE) production as the results of previous growth of toxigenic strains is the most crucial problem which may lead to the staphylococcal food poisoning outbreaks in humans. That is why the growth of three strains of Staphylococcus aureus was characterised in milk and modelled in dependence of temperature. For the lag phase duration of S. aureus 2064, the Davey model was used with the following result: ln(1/lag) = 1.973 - 87.92/T + 285.09/T2 (R2 = 0.962). The dependence...
Optimisation of Fermentative Parameters for GABA Enrichment by Lactococcus lactis
XiaoXue Lu, Chunyan Xie, ZhenXin Gu
Czech J. Food Sci., 2009, 27(6):433-442 | DOI: 10.17221/45/2009-CJFS
Gamma-aminobutyric acid (GABA) has antihypertensive and anti-stress functions on humans. Submerged fermentation of Lactoccocus lactis was regarded as an effective method to obtain GABA. In this study, the effects of fermentative parameters on the production of GABA was investigated. Firstly, one-variable-at-a-time experiments were performed in order to investigate the effects of significant factors influencing the GABA yield and monosodium glutamate (MSG) mole transformation percentage, i.e, the culture temperature, initial pH of the medium, MSG addition, and MSG addition time. Then, the response surface methodology (RSM) was applied to determine the...
Sanitation of fresh green asparagus and green onions inoculated with Salmonella
Miguel A. Martínez-Téllez, Francisco J. Rodríguez-Leyva, Ilce E. Espinoza-Medina, Irasema Vargas-Arispuro, Alfonso A. Gardea, Gustavo A. González-Aguilar, J. Fernando Ayala-Zavala
Czech J. Food Sci., 2009, 27(6):454-462 | DOI: 10.17221/138/2008-CJFS
The absence of good agricultural and manufacturing practices in the production and postharvest handling of fresh produce, such as green asparagus or green onions increase the contamination risk by biological hazards like Salmonella. The objective of this work was to investigate the efficacy of chlorine (200 and 250 ppm), hydrogen peroxide (1.5% and 2%), and lactic acid (1.5% and 2%) sanitisers during different exposure times (40, 60, and 90 s) on the reduction of Salmonella enterica subspecie enterica serovar Typhimurium in inoculated fresh green asparagus and green onions. Washing with clean water only reduced < 1 log10 CFU/g in both...
Antimicrobial properties of 11-cyclohexylundecanoic acid
Jan Šmidrkal, Tereza Karlová, Vladimír Filip, Markéta Zárubová, Iveta Hrádková
Czech J. Food Sci., 2009, 27(6):463-469 | DOI: 10.17221/181/2009-CJFS
The fact that milk fat contains many minor fatty acids is mostly neglected. It is known that 11-cyclohexylundecanoic acid is contained in cow's milk fat in the amount of 0.1-0.2%. It is also contained in human milk. 11-Cyclohexylundecanoic acid was synthesised, purified to 99.5% (GC) and its antimicrobial properties were investigated. It was found that 11-cyclohexylundecanoic acid has inhibitory effects on Bacillus cereus, Escherichia coli, and Fusarium culmorum from the concentration of 0.05 mmol/l, however, no antimicrobial effect on Saccharomyces cerevisiae has been determined. 11-Cyclohexylundecanoic acid was found also in...
Mercury and methylmercury content in chub from the Svitava and Svratka Rivers at agglomeration Brno
Kamila Kružíková, Jana Blahová, Renáta Kenšová, Jana Jurčíková, Dušan Hypr, Zdeňka Svobodová
Czech J. Food Sci., 2009, 27(6):470-476 | DOI: 10.17221/70/2009-CJFS
The aim of our study was to determine the total mercury and methylmercury contents in the muscle of indicator fish, to determine the total mercury contents in the sediment, and to evaluate the health risks associated with fish contamination. Chub (Leuciscus cephalus L.) were caught in seven localities on the Svratka and Svitava Rivers in the Brno agglomeration in 2007. The total mercury content was determined by atomic absorption spectrophotometry using an AMA 245 analyser. Methylmercury levels were determined by gas chromatography (using electron-capture detector) after acid digestion and extraction with toluene. The highest levels of total...