Czech Journal of Food Sciences, 2000 (vol. 18), issue 4
A new amperometric sucrose biosensor based on fructose dehydrogenaseOriginal Paper
V. Mastihuba, B. Leporisová
Czech J. Food Sci., 2000, 18(4):121-123 | DOI: 10.17221/8329-CJFS 
A new, ferricyanide mediated amperometric biosensor for estimation of sucrose in biological fluids is proposed based on fructose dehydrogenase coimmobilised with baker's yeast as a source of invertase on the surface of glassy carbon electrode. Potential +420 mV was applied to the electrode against saturated calomel electrode. Maximum current was observed at pH 6, linearity of response ranged from 0.01mM to 0.29mM. Concentration of potassium ferricyanide 2mM was found as the best value.
Influence of natural antioxidants on heat-untreated meat products qualityOriginal Paper
Ľ. Korimová, D. Máté, P. Turek
Czech J. Food Sci., 2000, 18(4):124-128 | DOI: 10.17221/8330-CJFS
The work deals with a study of the effect of natural antioxidants - rosemary extracts in powder and liquid forms, respectively, on the quality of a heat-untreated meat product. Effect of added antioxidants was estimated in samples taken from the meat product mixture, from a ready-made product immediately after smoking, after 28 days - at the expedition of the meat product and then after further 28 days of storing at different ambient temperatures. Marked positive effect of the applied antioxidants was noted especially during storing when the peroxide and thiobarbituric acid reactive substances (TBARS) values of fats increased more slowly compared to...
Screening of strains of Saccharomyces cerevisiae for ethanol fermentation of very-high-gravity substratesOriginal Paper
P. Bafrncová, D. Šmogrovičová, T. Foltin, I. Sláviková, J. Pátková
Czech J. Food Sci., 2000, 18(4):129-136 | DOI: 10.17221/8331-CJFS
A strain usable for fermentation of highly concentrated substrates by very-high-gravity fermentation technology (VHG) was selected on the basis of fermentation activity of the strains at high initial substrate concentrations and in the presence of exogenously added ethanol. The capacity of 35 distillery, baker's and wine strains of yeasts Saccharomyces cerevisiae to ferment high glucose concentrations was studied in a medium without ethanol addition and with addition of 10% ethanol by volume. Three strains were selected on the basis of biomass increments, degree of glucose utilization and concentration of produced ethanol. Maximum concentration...
Evaluation of beer quality by sensory analysisOriginal Paper
Nguyen Thi Thu Huong, H. Valentová, J. Velíšek, J. Čepička, J. Pokorný, F. Pudil
Czech J. Food Sci., 2000, 18(4):137-142 | DOI: 10.17221/8332-CJFS
The flavour of pasteurised and stored beer was evaluated by a panel of 12 assessors. The sensory analysis consisted of combined hedonic evaluation and sensory profiling using unstructured graphical scales and 31 descriptors. The obtained results were evaluated by multivariate statistical methods (principal components analysis and linear discrimination analysis) which allow visualisation of relations between individual descriptors and samples and enable classification of samples to groups according to pasteurisation intensity and storage time.
The use of polarity profiles of texture in the sensory evaluation of applesOriginal Paper
V. Horčin, I. Findová
Czech J. Food Sci., 2000, 18(4):143-147 | DOI: 10.17221/8333-CJFS
Research in the quality of horticultural products commonly applies sensory analysis which under minimized subjectivity approaches or coincides with other analytical methods with respect to its accuracy. Sensory analysis comprises many methods and tests. This article considers the test of textural polarity profile. Polarity profilograms are constructed for 29 varieties and new breeds of apple. The descriptors used characterize the textural quality of fresh and stored apples. The main advantage of polarity profiles is that they enable to determine not only differences between samples and varieties but also to find out changes in the textural quality...
Food consumption, its aspects and consequencesOriginal Paper
J. Hrubý
Czech J. Food Sci., 2000, 18(4):148-152 | DOI: 10.17221/8334-CJFS
Food consumption recording is a social need because the consumption is an indicator of the nutrition status that means the health status, of the population, and an economic factor. Food consumption trends in the nineties are characterized by a steep fall of most kinds of foods, mainly from animal sources. It is not necessary to adjust this fact with respect to recent data of the time series. Four commodities show a positive increase. The trend of food consumption is bound up with more slowly increasing incomes of the population than was the increase in food prices after their liberalization. The consequences of consumption trends do not imply any deterioration...
Antioxidant complex of bioflavonoids and ascorbic acid in apples (Malus pumila Mill.) - a reviewReview
J. Lachman, M. Orsák, V. Pivec
Czech J. Food Sci., 2000, 18(4):153-158 | DOI: 10.17221/8335-CJFS
In this review article it is given an information about the composition of flavonoid complex of apples (Malus pumila Mill.). It is discussed the influence of extrinsic and intrinsic factors on polyphenolic antioxidant content (varietal differences, influence of locality, year, maturity, pre-harvest treatment, storage, technological ways of processing) and the relation between the polyphenol content and the resistance of apple varieties. During storage there is an apparent decrease of both ascorbic acid and polyphenols. Contents of anthocyanins and chalcones are in positive correlation with resistance of apple trees to low and variable temperatures....
Specific microflora of packed meet - a reviewReview
I. Steinhauserová
Czech J. Food Sci., 2000, 18(4):159-163 | DOI: 10.17221/8336-CJFS
Meat is an attractive medium for microorganism multiplication due to its composition. The microflora of unpacked meat or of meat packed in wrapping plastic foil is significantly different from the microflora of vacuum-packed or controlled-atmosphere packed meat. Dominant microorganisms of unpacked meat are some species of the genus Pseudomonas sp., namely Pseudomonas fragi, Shewanella putrefaciens, Psychrobacter and Acinetobacter, which largely contribute to meat spoilage. From vacuum-packed or controlled-atmosphere packed meat were isolated mainly Brochotrix thermosphacta, heterofermentative lactobacilli...