Czech Journal of Food Sciences, 2007 (vol. 25), issue 5
Irradiation of spices - a review
Jana Sádecká
Czech J. Food Sci., 2007, 25(5):231-242 | DOI: 10.17221/684-CJFS 
Food irradiation is a process of exposing food to ionising radiation such as gamma rays emitted from the radioisotopes 60Co and 137Cs, or high energy electrons and X-rays produced by machine sources. The use of ionising radiation to destroy harmful biological organisms in food is considered a safe, well proven process that has found many applications. Depending on the absorbed dose of radiation, various effects can be achieved resulting in reduced storage losses, extended shelf life and/or improved microbiological and parasitological safety of foods. The most common irradiated commercial products are spices and vegetable seasonings. Spice irradiation...
Bread features evaluation by NIR analysis
Ondřej Jirsa, Marie Hrušková, Ivan Švec
Czech J. Food Sci., 2007, 25(5):243-248 | DOI: 10.17221/683-CJFS
Bakery characteristics of wheat dough and the final product and their predictability by NIR technique was investigated using 231 variety and commercial wheat samples (crop years 2003-2005). The behaviour of doughs was assessed with Brabender maturograph and OTG (Germany), the final product quality was evaluated by the baking test and image analysis. NIR spectra of flours were acquired on a NIRSystem 6500 spectrometer. Calibration equations for the selected rheological characteristics were computed by WINISI II using mPLS regression. The quality of prediction was evaluated by means of coefficients of correlation between measured and predicted values...
Effects of wheat cultivar and harvest year on technological quality studied by univariate and multivariate analyses
Ivan Švec, Marie Hrušková, Ondřej Jirsa
Czech J. Food Sci., 2007, 25(5):249-258 | DOI: 10.17221/681-CJFS
The effects of wheat cultivar and harvest year on the wheat technological quality were studied by univariate and multivariate statistical methods. Two wheat varieties sown in the harvest years 2003-2005 were used, the first one of European (cultivar Bezostaja, RUS), the second one of American origin (cultivar Jagger, USA). The evaluated parameter values indicated otherness of technological quality of the varieties studied, mostly in the milling effectivity and in proteins contents and quality. Principal component analysis (PCA) results suggested these differences, but their verifiability based on ANOVA testing was not proved. The harvest year mostly...
Analysis of the lipid fractions of coffee creamers, cream aerosols, and bouillon cubes for their health risk associated constituents
Lenka Karšulínová, Blanka Folprechtová, Marek Doležal, Jana Dostálová, Jan Velíšek
Czech J. Food Sci., 2007, 25(5):257-264 | DOI: 10.17221/679-CJFS
Fifteen coffee creamers, 10 cream aerosols, and 5 bouillon cubes from the retail market were analysed, principally for their contents of trans-fatty acids that are known to increase the risk of coronary heart disease, and for their contents of 3-chloropropane-1,2-diol (3-MCPD) fatty acid esters that possibly have a bioaccumulation potential. The contents of trans-fatty acids in coffee creamers, cream aerosols and bouillon cubes were in the range of 0.2-32.8%, < LOD - 6.0%, and 0.5-2.1% of total fatty acids, respectively. All samples contained high levels of 3-MCPD fatty acid esters that were determined after releasing the free 3-MCPD by methanolysis....
Acrylonitrile in food contact materials - two different legislative approaches: comparison of direct determination with indirect evaluation using migration into food simulants
Ivana Poustková, Jan Poustka, Luboš Babička, Jaroslav Dobiáš
Czech J. Food Sci., 2007, 25(5):265-271 | DOI: 10.17221/678-CJFS
In this study, the comparison was carried out of two different legislative approaches for acrylonitrile content assessment in food contact materials based on the former analysis using gas chromatography with nitrogen-phosphorous detection, and the recent evaluation using acrylonitrile migration into food simulants - distilled water, 3% acetic acid, 10% ethanol, and 95% ethanol, based on liquid chromatography with ultraviolet detection. Different samples were tested: 7 kitchen device parts and 16 acrylonitrile-butadiene-styrene and styrene-acrylonitrile granulates. The level of acrylonitrile content in founded polymer mass was in the range from 0.4...
Characterisation of Lactobacillus rhamnosus VT1 and its effect on the growth of Candida maltosa YP1
Denisa Liptáková, Ľubomír Valík, Andrea Lauková, Viola Strompfová
Czech J. Food Sci., 2007, 25(5):272-282 | DOI: 10.17221/680-CJFS
The combined effect of initial amount of 18 h L. rhamnosus VT1 inoculum and incubation temperature on the growth of Candida maltosa YP1, an oxidative food spoilage yeast strain, was primarily modelled and studied by standard response surface methodology. This study resulted in the following linear regression equations characterising lag time and growth rate of C. maltosa YP1 in milk in competition with the potentially protective lactobacillus strain. Lag-phase of C. maltosa was strongly influenced by the amount of lactobacillus inoculum (V0) and incubation temperature (1/T). The synergic effect of...
Thermal inactivation of Enterococcus faecium
Vladimiír Špelina, Ljuba Schlemmerová, Aleš Landfeld, Karel Kýhos, Pavel Měřička, Milan Houška
Czech J. Food Sci., 2007, 25(5):283-290 | DOI: 10.17221/682-CJFS
Data for thermal inactivation of working suspension of Enterococcus faecium in model solutions were acquired and used to develop a mathematical model for thermal inactivation of the bacterium. The model is valid within the water activity range 0.97 to 0.99; pH range 6.0 to 7.6; temperature range 60°C to 65°C, and was determined for the microorganism concentration ranges of 102 per ml to 108 per ml of the model inactivation solution. An Excel procedure was developed in Visual Basic language which enables the calculation of the final concentration of the microorganism from the input data for pH, aw, logN0,...