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Water-insoluble β-(1,3)-D-glucan (lichenan) was determined in 43 samples of various cereal (oats, barley, wheat, millet) and pseudocereal (buckwheat, amaranth) cultivars using a modified procedure with fungal α-amylase (Fermizyme P 300). The content of water-insoluble β-glucan varied in the dependence on the cereal species and cultivars. The highest content was registered in covered oat cultivars (Cyril and the new breeding cultivar PS-100) ranging from 26.7 to 28.2 g/100 g dry matter (d.m.) followed by less traditional cereals such as millet (Panicum miliaceum L.), amaranth (Amaranthus sp. L.), and buckwheat (Fagopyrum) - more than 20 g/100 g d.m. A somewhat lower average content of water-insoluble β-glucan was found in wheat - 12.7-16.2 g/100 g d.m., in spelt wheat - 8.5 g/100 g d.m., and in oats - varying between 15.3 and 18.7 g/100 g d.m.

Enzymes with high specific activities at low temperatures have potential uses in the food industry. Cold-adapted microorganisms are potentially useful sources of cold-active enzyme. To find cold-adapted β-galactosidase, we isolated several cold-adapted microorganisms from glacier zone soil. One cold-adapted β-galactosidase producing strain was obtained. The biochemical characteristics and the results of 16S rDNA sequencing identified the strain as Rahnella aquatilis. The enzyme was purified by column chromatography after which a single protein band migrating near 60 kDa was observed by means of SDS-PAGE. The β-galactosidase was optimally active at 35°C and at pH 6.5 when assayed with o-nitrophenyl-β-D-galactopyrano-side as substrate. The enzyme activity was sensitive to temperatures above 40°C and was undetectable at 45°C. Metal ions Mn²⁺and K⁺ activated the enzyme while Cu²⁺, Zn²⁺, Fe³⁺, and Al³⁺ inhibited the activity. The enzyme was also assayed for lactose hydrolysis. When milk is treated with the enzyme at 30°C for 2 h, the degree of lactose hydrolysis can reach 80%. It has, thus, potential applications in the food industry.

The inhibition of mutagenicity was assessed by Ames test by bacterial strains Salmonella typhimurium TA98 and TA100 using two mutagens and methanolic extracts of healthy fresh berries of blue grapevine varieties - St. Laurent, Portugal, André and white varieties - Chardonnay, Welschriesling, Pinot Gris and berries infected with Botrytis cinerea fungus. As model mutagens, two compounds whose presence in food is real, 2-amino-3-methyl-3H-imidazo-(4.5-f-)-quinoline (IQ), arising from certain heat treatments of meat and acting as indirect mutagen after metabolic activation, and N-nitroso-N-methylurea (MNU) acting as a direct mutagen, were applied. An increased risk of MNU is due to its possible endogenous formation. Fermentation sediment after vinification of the varieties Chardonnay, Welschriesling and André was tested by similar experimental system. All extracts showed strong positive inhibition of mutagenicity, berries infested with Botrytis cinerea also in diluted extracts. Positive inhibition was demonstrated also by fermentation sludge.

This review article is a part of the survey of the generally accepted biosynthetic pathways that lead to the most important natural pigments in organisms closely related to foods and feeds. The biosynthetic pathways leading to xanthones, flavonoids, carotenoids, and some minor pigments are described including the enzymes involved and reaction schemes with detailed mechanisms.

The effects of the pressing technology and clarification of white grape musts on concentrations of phenolic compounds and their antioxidative capacity were investigated. Four different varieties were processed by hydraulic or pneumatic pressing technologies. In the individual stages of pressing and after the application of different doses of the clarification agent, must samples were analysed for the content of polyphenols and the antioxidative capacity. The highest concentrations of caftaric acid were estimated in the musts made by hydraulic pressing from grapes of Welschriesling variety. On the other hand, musts made from grapes of Grüner Veltliner showed the highest contents of trans-piceid in both variants of pressing. The values of antioxidative capacity of the must samples analysed were not significantly different. The influence of clarification on the changes of phenolic substances in young red wines of Saint Laurent variety was also studied. Six various clarifiers were tested as applied in two different doses. Polyvinylpolypyrrolidone caused the highest losses of trans-resveratrol in the course of red wine clarification. The concentrations of catechin, epicatechin, and total anthocyanins as well as the colour parameters of red wines were influenced at most by the application of egg white.

Rheological and textural characteristics were studied in a set of 11 samples of yoghurt-modified mayonnaise at 15, 20, and 25°C. The rheometer Rheostress 300 was used to determine the static yield value, apparent viscosity, thixotropy, and elasticity. The sensory texture and flavour profiles were developed and determined in agreement with the respective international standards, using a group of selected and trained assessors. The yield value and apparent viscosity substantially decreased with increasing temperature, but thixotropy and sensory characteristics were not significantly affected by temperature. Linear and semilogarithmic relations were observed between the analytical parameters, but more complex relations, showing a maximum or a minimum, were found in some cases. Thixotropy was related to most of the sensory parameters, viscosity was related to spreadability, and significant relationships existed between the texture acceptability and the flavour acceptability. Rheological measurements were thus useful for a rapid prediction of the sensory properties of yoghurt-modified mayonnaises, but could not be used to replace any textural analysis.

While several validated methods have been developed for analysis of phenylurea herbicides in staple food plants, analytical procedures suitable for their quantification in minor crops such as poppy seeds are not available. For the registration of isoproturon use in this crop, the documentation of dynamics of its residues following treatment was requested. To accomplish this task, HPLC-MS/MS method was developed. Extraction of residues was realised by methanol-water mixture, Supelclean LC-18 SPE cartridges were used for purification of crude extracts. For HPLC separation of isoproturon SPE fraction Lichrospher C18 column (25 cm × 4 mm, 5 μm) was employed. For detection and quantification of target analyte, mass spectrometer with ion trap analyser operated in positive atmospheric pressure chemical ionisation (APCI) and MS/MS mode was used. Following performance parameters of method were obtained: detection limit 0.01 mg/kg, recovery 84%, and repeatability 7%.

This work compared the use of polymerase chain reaction (PCR) and the conventional CSN/ISO/10272 culture-based methods in the detection of Campylobacter species in ready-to-eat meals made from chicken meat. PCR was carried out with the primers specific to C. jejuni, C. coli, C. lari, and was modified with an internal control. The detection of campylobacters by PCR was performed on both untreated and spiked samples of real food purchased in local stores. For PCR, the detection limit was 2 CFU/g after 48 h enrichment in Park and Sanders broth. Duplex PCR proved to be highly reliable in the detection of campylobacters in different food types. Without extra spiking, samples from a global fast food chain exhibited positive amplification of the PCR product while but negative results were obtained from the cultivation of the same samples.

The colour of the laboratory prepared pasta was evaluated with respect to wheat flour types (M1 bright, M2 semi-bright, and M3 semolina), egg-ratio (0, 1, 2), and non-traditional cereals (archaic wheat species, tritordeum, spring barley, millet, lupin, buckwheat, and soya) supplements. The flour colour measurement confirmed its dependence on the wheat species milled - M3 obtained from durum wheat had a lower whiteness L* (89.6) and a higher yellowness b* (22.2) than the flour from common wheat (e.g. 93.6 and 8.1 for M1, respectively). As presumed, with the rising egg-ratio pasta yellowness increased - for M1-pasta, the calculated colour differences ∆E in pairs one-egg/eggless and two-egg/eggless were 1.1 and 4.7, respectively, while for M2- and M3-pasta ∆E values were only 0.8 and 1.5, respectively. The colour impacts of non-traditional cereals as 10% supplements differed between archaic wheat species, tritordeum, barley, and alternative cereals (millet, lupin, roasted buckwheat). In comparison to the standard, the greatest positive colour gain was brought by the lupin fortification (130% yellowness increase), while the worst appesred roasted buckwheat (10% decrease of whiteness, 210% increase of redness). At 20% non-traditional cereals supplements compared for M2- and M3-pasta, the highest positive increase of the pasta colour sensory perception was caused by corn and lupin additions in both pasta samples. The increase was slightly higher with M1-pasta (175%) than with M3-pasta (170%). In the mean of both pasta samples, yellowness L* increased from the standard pasta value 13.6 to 24.0 as measured for corn and lupin fortified pasta.

Polyphenolic compounds are widely distributed in plants and are a common part of human diet. Polyphenols are known to be potent bioactive molecules, predominantly with protective effects. Many of xenobiotics, including polyphenols, influence the activities of various enzymatic systems. Such interactions can modulate the activities of co-administered drugs. The identification of polyphenols' potential for the interactions based on metabolic changes is thus necessary. Cytochrome P450, which takes part in the metabolism of more than 90% of used drugs, is an important enzymatic system which can be influenced. We therefore determined the influence of quercetin and trans-resveratrol on the activity of cytochrome P450 1A2 in rats. A perfused rat liver model and phenacetin as a marker of 1A2 activity were used. Moreover, we studied the dependence of trans-resveratrol's activity on sex in both sexes. Trans-resveratrol did not influence the 1A2 activity, but it enhanced sexual differences in the metabolic activity. Our results also confirmed different metabolic activities between sexes. Female rats metabolised faster through 1A2. Based on our results, we suggest that quercetin is an inhibitor of cytochrome P450 1A2 isoenzyme.

The determination of polyphenols by spectrophotometric detection is complicated due to their low concentrations in beer. The beer samples have to be pre-concentrated before using the spectrophotometric detection for their quantification. An analytical method based on solid-phase extraction (SPE) and followed by high performance liquid chromatographic separation with diode-array detection is used for the determination of free gallic, protocatechuic, caffeic, p-coumaric, ferulic and salicylic acids, of (+)-catechin, (-)-epicatechin, and quercetin. These phenolic compounds participate in colloidal and sensory stability of beer. Six different SPE cartridges were tested and three different types of elution with the most appropriate solvents (acetonitrile, acetone and methanol) were used. The performance of the HPLC method was assessed by the evaluation of parameters such as absolute recovery, relative standard deviation (RSD - lower than 10%), the limit of quantification (LOQ), and the limit of detection (LOD). The polyphenol content in various types of Czech beer is presented.

Germination is one of the most effective ways of preparing grain legumes for consumption. Because it involves the total or partial elimination of some anti-nutritional compounds, it is also one of the simplest methods of enhancing the palatability of grain legumes, thereby increasing their consumption as a valuable source of nutrition. The main objective of this paper is to describe the changes that take place in α-galactosides during germination. During germination, galactose molecules gradually become detached from α-galactosides due to the effect of the enzyme α-D-galactosidase activated during the process. To simulate the degradation of α-galactosides during legume seed germination, we applied nine equations to the evaluation of the experimental data obtained with the germination of three types of grain legume seeds; mung bean, chickpea, and lentil.

Echinacea species are popular herbal medicine and food supplements for enhancing the immune system. This study was conducted with the aim of developing an efficient heat reflux extraction of caffeic acid derivatives from dried adventitious roots of Echinacea purpurea obtained in bioreactor cultures. Water, methanol (20, 40, 60, 80, and 100%), and ethanol (20, 40, 60, 80, and 100%) were used as solvents for the extraction of caffeic acid derivatives. Another parameter used for the optimisation was the solvent temperature during extraction. The treatment of samples with 60% ethanol at 60°C for 2 h proved to be the most suitable procedure. This treatment was also responsible for the higher yields of total phenolics, flavonoids, and polysaccharides.

Polyphenols can greatly affect the sensorial characteristics and stability of wine. The concentration of polyphenols in wines is very low, the sample must be thus concentrated before the analytical measurement. The extraction on solid phase (SPE) is a suitable method for the isolation, purification, and concentration of polyphenols from complicated matrices. RP-HPLC with diode array detection was used for the separation and identification of polyphenols. A library of absorption spectra of standards was created and used for the identification of 14 polyphenols in wines. The contents of the individual polyphenols and their changes after the addition of four tannin preparations were determined in eight white and two rosé wine samples. The influence of the flavour profile of the applied tannin preparations on sensorial characteristics of wines was established

Two cultivars (Nicola and Saturna) largely distinguishing from each other in cooking behaviour and one cultivar (Agria) grown in six different cultivation regimes were tested by the CPEM (cooked potato effective mass) method for the potato sloughing assessment. The sloughing process is characterised by two cooking and disintegration stages, from which two basic CPEM parameters are derived: cooking time as the starting point of disintegration and the rate of the disintegration. Both parameters are analysed as functions of the tuber density in linear models of both stages. Significant differences in CPEM parameters and in the linear models were observed between different varieties. The data from two-year measurements were in basic agreement with our previous concept of the limited contribution of starch in the first cooking stage and of its more important role in the second disintegration stage of sloughing. The results indicated a close association between the mechanisms controlling sloughing and the tuber density in the cultivars Agria and Saturna. A different cooking behaviour was observed in the case of the typical salad cultivar Nicola with a considerably lower cooking time sensitivity to the tuber density.

Patatin relative abundance in SDS-extractable protein and patatin content in dry matter were evaluated in tubers of forty processing and table potato cultivars usually cultivated in the Czech Republic, Germany, and the Netherlands. The patatin characteristics were evaluated over three experimental years. Patatin relative abundance in the processing cultivars achieved on average a significantly higher value (P < 0.001; Tukey HSD test) than patatin relative abundance in the table cultivars, resulting in average values of 25.80% and 21.59%, respectively. A high patatin relative abundance (over 30% in extractable protein) was determined only in the case of two cultivars: Vaneda (average 31.29%) and Tomensa (average 31.24%). Patatin content in tuber dry matter was significantly higher in the processing potato cultivars in all three experimental years (P < 0.001), attaining a mean of 1.28% with the processing cultivars and 1.03% with the table cultivars. The direct effect of the cultivar on patatin relative abundance in SDS-extractable protein was higher (33.1% for processing potato cultivars and 48.1% for table potato cultivars) than the effect of the growing year (15.6% for processing potato cultivar and 22.8% for table potato cultivars).

Buckwheat is introduced into the diet as an alternative crop of renewed interest due to its nutritive and health-promoting value. Experiments with animal models have demonstrated that buckwheat flour may alleviate diabetes, obesity, hypertension, and hypercholesterolemia. A number of nutraceutical compounds exist in buckwheat grains and other tissues. These are a rich source of starch, proteins, antioxidants, and dietary fibre as well as trace elements. The biological value (BV) of buckwheat proteins is comparable to BV of other protein sources. Besides high-quality proteins, buckwheat grains contain some components with prophylactic value: flavonoids, fagopyrins, or thiamin-binding proteins. For the food industry, buckwheat grains are a valuable raw material to be used for the production of functional foods. Buckwheat flour may be a valuable and important ingredient in diets or food products, taking into consideration its nutritive value and potential promotion of human health.Keywords:

An investigation was conducted to find out the effects of two triazole fungicides (triadimefon (TDM) and hexaconazole (HEX) - 15 and 10 mg/l per plant, respectively) on the biochemical constituents and tuber quality of white yam (Dioscorea rotundata Poir.). The exposure of white yam plants to the fungicides showd increased chlorophyll, carotenoids, xanthophylls, and anthocyanin contents and altered the membrane integrity in terms of electrolytic leakage and lipid peroxidation. The triazole treatments enhanced the accumulation of proline and total phenols in tubers. The visible symptoms of fungicides appeared as thickening and darkening of leaves. Both the triazoles increased the antioxidants (ascorbic acid, reduced glutathione, and tocopherol) contents. The data suggests that, apart from their fungicidal properties, the application of triazole fungicides may be a useful tool to increase the tuber quality in yam plants.

Geometrical features of lentil seeds (Lens culinaris Medik) were analysed using the image analysis LUCIA system Ver. 3.52. The values of the weight of 1000 kernels, kernel density, specific volume, specific surface area, and surface area of 1000 kernels of red and green lentils were determined as 66.61 and 138.56 g, 1504.5 and 1376.4 kg/m³, 0.6647 and 0.7265 cm³/g, 0.594 and 0.579 m²/kg, 395.4 and 801.9 cm²,, respectively. The lentil volume was simulated by an oblate spheroid and two sphere segments and the volumes obtained with both models were compared with that obtained by pycnometric method. Percentage differences of the two sphere segment approximation for red and green lentils were 4.4% and 4.2%, respectively. The height (thickness) of lentils was constant and practically the same with both varieties (2.6 mm) and therefore it was possible to simplify the geometrical models. Thus, 2D image analysis is suitable for a quick evaluation of the specific volume and surface area of grains on the basis of the projected area (equivalent diameter) without the measurement of the height. Image processing provides a simple, rapid, and non-invasive methodology to estimate lentil geometric features and engineering parameters.

This study proposes a method for estimating the content of tea in tea-based products. Broadly, this methodology is based on selecting chemical markers of the quality and authenticity of tea (and, therefore, of tea-based products), optimising the relevant analytical methods, and determining variations (type, origin, quality) among samples of green and black leaf teas. The contents of the selected markers (theobromine, caffeine, theanine, and total polyphenols) in tea-based products (iced teas, instant teas) were determined. Then, the dry tea content in these products, expressed as the equivalent amount of dry tea leaves, was calculated on the basis of two sets of mean data for these analytes: average literature data, and the mean experimental data obtained with our samples of leaf tea. With regards to the latter, we propose to use of the following averages for caffeine, theobromine, theanine, and polyphenols: for 100 g of black tea-based products 1.9 g, 0.13 g, 1.3 g, and 9.1 g, respectively; for 100 g of green tea-based products 1.9 g, 0.16, 1.7 g, and 14.7 g, respectively. Using this method, we found that approximately one third of the analysed samples failed to meet the tea extract levels required by German and Austrian legislations, while about 10% did not comply with the less demanding Czech legislative requirements.

In this work the Cd, Cu and Zn accumulation in potatoes, their influence on starch, water-soluble (WSS) and water-insoluble saccharide (WIS) contents and content of heavy metals in various saccharide fractions of potatoes were determined. The fraction of WSS was isolated by Somogyi method, the WIS fraction was obtained from delipided portion of potatoes. Enhanced pseudototal Cd contents in relationship to limit value 0.7 mg/kg of soil were determined in 13 soil samples (0.72-1.06 mg/kg). Contents of Zn and Cu were lower than their limit values in all observed soil samples. Observed heavy metals have not influence on their accumulation in potatoes, the Cd content in potatoes (0.0015-0.0042 mg/kg f.m.), Cu (0.0590-0.1780 mg/kg f.m.) and Zn contents (0.1887-0.3517 mg/kg f.m.) were also lower than their limit values. The proportion of observed heavy metals in selected saccharide fractions: Cd (mg/kg): 0.017-0.140 (starch), 0.0133-0.2293 (WIS), 0.8711-109.7713 (WSS); Cu (mg/kg): 0.067-1.433 (starch), 0.2844-6.9877 (WIS), 18.0134-1070.5216 (WSS); Zn (mg/kg): 6.667-66.300 (starch), 0.7869-23.3673 (WIS), 101.4842-4020.790 (WSS)

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 vegetables. The most effective sanitiser evaluated for fresh green asparagus and green onions disinfection appeared to be 2% lactic acid reducing Salmonella growth close to 3 log₁₀ CFU/g. Hydrogen peroxide was the least effective agent for Salmonella Typhimurium reduction. No effect was observed of the exposure time of inoculated product to sanitiser up to 90 seconds. These results confirm that lactic acid could be used as an alternative for fresh green asparagus and green onions sanitation.

In the present study, the main purpose was the selection of antagonistic starter cultures for pickle and olive fermentation processes. The chemical and microbiological properties of fermented 70 pickle and 16 olive samples collected from the province of the west part of Turkey were analysed. Subsequently, lactic acid bacteria strains producing bacteriocin-like metabolites were isolated and identified. From 86 samples, 16 isolates were chosen, depending on their partial antimicrobial activity against at least one selected indicator. 13 out of this 16 isolates were identified as Lactobacillus plantarum whereas 3 of them proved to be Lactobacillus pentosus. Moreover, all the relevant isolates were found to be potent acid producers. All these results obviously suggest that the isolated Lactobacillus plantarum 9 and 25 were appropriate for them to be proposed as starter cultures in fermented pickle and olive production.

The problems of soil hygiene and contents of the following heavy metals: cadmium, cobalt and nickel in the productive parts of plants in the location of Agricultural Cooperative Štrba in Poprad County were discussed in the presented work. Above-mentioned location is found in the neighbourhood with a chemical factory Chemosvit Svit. The achieved results show that the soil hygiene in this region is mainly affected by the activity of this chemical factory. This factory is producing many risky substances and their results can be seen in the condition of soil hygiene and in the quality of farmed plants. The results of monitored heavy metals (Cd, Co, Ni) prove that the content of cadmium and nickel is the main polluting factor of soil in this region. The increased contents of these elements in soil produce a high risk of the uptake to plants. This further affects the technological quality along with the quality of hygiene of farmed products and finally the food itself as well. A higher attention needs to be paid to cobalt too, because it proved quite high cumulation ability in soil.

Pulsed Electric Field (PEF) processing inactivates microorganisms without significant adverse effects on flavor and nutrients. In this work was studied the transformations of antheraxanthin and mutatoxanthin when natural orange juice is treated by pasteurisation (90°C, 20 s) or PEF (30 kV/cm, 100 μs), and also its evolution during seven weeks of storage in refrigeration at two different temperatures (2°C and 10°C). The results showed that antheraxanthin concentration decreased during the storage. The decrease was greater in the untreated, pasteurised and PEF-treated orange juices stored at 10°C and this carotenoid was not detected from the 6^th week onwards. The same result was observed in the PEF-treated juice stored at 2°C. However, in the untreated and pasteurised juices stored at 2°C, this carotenoid was detected throughout the storage period, although its concentration decreased. Mutatoxanthin was detected in the 6^th week of storage, appearing in the cases in which antheraxanthin disappeared. This was not observed in the untreated or pasteurised orange juices stored at 2°C.

The work was aimed at the growth suppression of cultured listerias strains by cultured lactococci strains or commercial mesophilic cheese cultures during common cultivations in the model UHT milk system (0.5% w/w of milk fat content) at 30°C during 18 h aerobically. Milk was primarily fermented by lactococci at the level of 10⁸ CFU/ml and secondarily contaminated by listerias at the level of 10³ CFU/ml. The most intensive growth suppressions of both Listeria innocua (CCM 5884 or Ln-03) strains were caused by Lactococcus lactis subsp. lactis (LCC 416 or CHCC 2281) strains or DELVO-ADD® 100-X DSF cheese culture; the listerias growth reductions was from the level of 10³ CFU/ml to 10⁰ CFU/ml. Obtained results should be applied to dairy industry provided that HACCP, GHP and GMP systems must be observed.

The changes of vitamin C content in relation to Cd, Pb and Zn accumulation in 6 potatoes varieties: very early (Junior, Impala), early (Livera), middle early (Agria), medium-late (Asterix, Desirée) were surveyed in this work. The soil used in pot trial had pseudototal (in soil extract of aqua regia

The fractionation of Cd, Cu, Mo, Ni, and Zn species in extracts of rye (cv. Fernando) seedlings (grown up in both standard and Cd²⁺-enriched medium) and rye flour was performed by SEC/ICP-MS method. The majority of Cu, Zn, and Ni in all samples were bound in the 1-2 kDa fraction. Molybdenum occurred in all samples in the fraction of 3 kDa. During five days of cultivation in a solution of 30 µmol/l Cd²⁺, the plants accumulated as much as 5 mg/kg fresh matter of Cd, but its soluble portion represented only 12-15%. The prevailing portion of Cd complexes was contained in the fraction of 3 kDa, while the minor part occurred in the fraction of 20 kDa. The speciation of elevated Cd in plants differs from that of other metals present at a physiological level. The metal-rich fractions of the extracts of all samples (i.e. those of 1-2 kDa) were refined by immobilised metal affinity chromatography. The isolated ligands of trace elements were peptides rich in dicarboxylic aminoacids.

Enterotoxigenic Bacillus cereus was detected in a variety of meat stuffs (36), ready-to-cook products (5), and swabs (7). The bacterial colonies isolated from PEMBA agar were identified as B. cereus. The 85 isolates were examined for the enterotoxin production using both TECRA-VIA and BCET-RPLA kits (ELISA - 47, RPLA - 38). Thirty two isolates (66%) were positive for enterotoxin using the ELISA test while only 15 isolates (39%) gave positive results in the RPLA test system. In total, 178 (91.8%) and 164 (84%) of the strains isolated in our laboratory (from various foods) were enterotoxigenic as determined using TECRA-VIA and BCET-RPLA, respectively. Parallel enterotoxin positive results obtained using both tests were demonstrated in only 9 isolates from 19 assessed (47.4%). Coincidental negative results from both kits were established for 3 isolates (15.8%) only. The isolates of B.cereus from meat were resistant to cephalothin (57%), clindamycin (14%), oxytetracycline (14%), and erythromycin (7%). The isolates from swabs were resistant to cephalothin (83%), erythromycin (16%), clindamycin (16%) and enrofloxacin (16%).

The quality of water has to be controlled and monitored by drinking water suppliers during all stages of the treatment process from the water sources to the end of distribution systems. The research, performed in Czech Republic from 2006 to 2008, deals with the assessment of the affect of water tanks on the quality of water supplied to consumers, specifically from various points of view: microbiological, biological and physic-chemical changes in water accumulation. Also studied was the influence of the air on the quality of accumulated water (secondary contamination), the influence of the structural layout and hydraulic ratios. In the project quick screening methods (paddle testers and BART^TM tests) were applied in the collection of water samples and scrapings from wetted surfaces of water tanks. The results of the contamination degree discovered in the course of the project solution will serve as basic data for a scale that should evaluate the degree of water tank pollution as well as for resulting corrective measures or optimisation of water tank cleaning. The recommendations of limits for a scraping sample are based especially on the microbiological parameters. Secondary air contamination plays an important role in maintains of biologically stable water. Based on the number of microbial contamination discovered water tanks will be categorised and methods of suitable measures to be taken will be stipulated, operation optimisation as well as cleaning (schedule, methods and frequency of cleaning). The water quality in a storage tanks depends on their maintenance, e.g., to prevent the plaster falling on water surface, the use of antifungal surface coatings (prevention the growth of fungi on walls), the use of ceramics surface of reservoir walls, dark conditions (no windows or blue sheets) in all technological units, the prevention of dust fall out, the selection of suitable air condition and special air filters.