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Cereals are generally known to have a positive influence on the general state of the human organism. The attention of the nutritional experts is paid especially to oats and barley. Besides their accessibility, these cereals are interesting due to their relatively high contents of soluble non-starch polysaccharides (fibrous material), out of which beta-glucans have a dominant position from the aspect of health benefit. This paper presents a brief review of the latest knowledge on the positive effects of beta-glucans on the consumer's health. The structure, occurrence, sources, and positive physiological effects of beta-glucans on the cardiovascular system but also their antibacterial, antitumoral, immunomodulant, and radioprotective properties are mentioned. In the paper are given examples of beta-glucans exploitation as functional ingredients in food, cosmetic, and pharmaceutical industries and as food additives on the basis of cereal fibres and cereal beta-glucans.

A collection of 250 enterococci isolated from various food-stuffs were used to investigate seven virulence determinants and the microbial susceptibility of eight antibiotics. Species-specific PCR revealed the presence of E. faecalis (127 isolates), E. faecium (77 isolates), E. casseliflavus (21 isolates), E. mundtii (19 isolates) and E. durans (6 isolates). Multiplex PCR for virulence factors showed that out of the 250 isolates tested, 221 carried one or more virulence-encoding genes. Beta-haemolytic activity was also evident in enterococcal species other than E. faecalis and E. faecium. Species other than E. faecalis and E. faecium isolated from food may also be virulent. Antimicrobial susceptibility was tested using the disk diffusion method. It showed that out of 250 isolates, 114 were resistant to cephalothin and 94 to ofloxacin. Lower antibiotic resistance was seen with ampicillin, chloramphenicol, gentamicin and teicoplanin. None of the isolates was found to be resistant to vancomycin. The results of this study show that food can play an important role in the spread of virulent enterococci through the food chain.

The occurrence of Listeria monocytogenes, Salmonella spp., Bacillus cereus, Staphylococcus spp., Enterococcus spp., and Escherichia coli in raw food materials, food products, and on food contact surfaces after sanitation was investigated during the period of 2005-2006 in three dairy cattle farms (120 samples), one dairy (124 samples), and two meat processing plants (160 samples). A total of 1,409 isolates were identified. The epidemiological characterisation and determination of the virulence factors and antimicrobial resistance were performed on selected isolates. The level of bacterial contamination generally decreased during the production process (the contamination of food products was lower than that of raw material). However, the contamination of food contact surfaces was relatively high even after sanitation. Moreover, specific microbiological profiles were found on the inside equipment surfaces in dairy facilities, where genetically closely related multi-resistant strains persisting in biofilm communities may occur as it was demonstrated for staphylococci. Although the occurrence of potentially significant pathogens was not high, the microorganisms such as L. monocytogenes, Salmonella spp., and shiga-toxin positive E. coli principally contaminated the meat processing plants. B. cereus isolates, among which 76% were positive for diarrhogenic enterotoxin, typically occurred on the inside equipment surfaces and in the heat-treated products.

A non-destructive Vis-NIR spectroscopy (400-1000 nm) method was developed to evaluate the loss of freshness of sliced and commercially packaged cooked ham and turkey ham without any sample manipulation. The spectra were recorded at 0, 30, 40, and 60 days using a camera, spectral filter (400-1000 nm) and a halogen floodlighting system which had been were developed and calibrated for the purpose. Physico-chemical, biochemical, and microbiological properties such as pH, total volatile basic nitrogen (TVB-N), ATP breakdown compounds, and colony-forming units were determined to predict the degradation of freshness. The image spectra obtained from visible and SW-NIR spectroscopy were related to the storage time of the samples. A PLS-DA model was developed independently for packaged or unpackaged samples using the second derivative of the spectra. Mean R2 prediction obtained for cooked ham was 0.915 and 0.949 for Turkey ham. The technique developed could be applied to monitoring the freshness of commercial packed cooked ham and turkey ham as a non-destructive technique. Further studies will be needed to check the spectra obtained from samples of different commercial brands in order to evaluate more precisely the efficiency of the method.

The use of dielectric properties of agricultural products for sensing moisture in grain and seed and their application in radio-frequency and microwave dielectric heating is discussed briefly. Values for the dielectric properties of a number of products, including grain and seed, fruits and vegetables, and poultry products, are presented graphically to show the dependence of these properties on frequency, moisture content, and temperature. The potential for using the dielectric properties to sense quality factors other than moisture content is also considered.

The aim of this study was to determine both the occurrence and the genetic basis of resistance to erythromycin among 1,235 Staphylococcus spp. isolates obtained between 2000 and 2006 from (a) raw milk and meat (1,704 samples), (b) foodstuffs produced from these (451 samples), and (c) contact surfaces at processing plants and dairy farms (363 samples) in the Czech Republic. Isolates were screened by broth microdilution method for resistance to erythromycin and further 11 antimicrobial agents. In addition, isolates were screened by agar dilution (erythromycin range 1-128 mg/L) and D-zone test for inducible resistance to macrolides, lincosamides and streptogramin B (iMLSB). Forty isolates were found to be either resistant or intermediate to erythromycin; of these, more than 50% were identified as S. epidermidis. A total of 15 resistant isolates of staphylococci originated from foodstuffs. Resistance mediated by methylation - i.e. iMLSB-resistance (10 isolates with the erm(A) or erm (C) gene) and constitutive MLSB-resistance (one isolate with the erm (B) and erm (C) genes) - exhibited a significantly high level of resistance to erythromycin. In contrast, the efflux mechanism encoded by the msr(A) gene, the inactivation mechanisms of resistance encoded by the mph(C) gene and/or their combination led to lower MIC values. The efflux gene (A) dominated among the erythromycin-resistant isolates (65% of resistant isolates). This first report on the resistance of Staphylococcus spp. to erythromycin in the Czech Republic illustrates that, while occurrence was low, isolates from food were nevertheless carriers of erm (A), erm (B), erm (C), msr(A) and mph(C) genes for resistance to erythromycin and, therefore, represent a potential thread to humans.

The influence of different storage temperatures (5 deg C and 15 deg C) on the quality of vacuum-packed dry fermented sausage Polican was determined. The salami mixture, finished salamis (the maturing period of 30 days), and salamis stored for 30, 60, 90, and 120 days were analysed. The analyses performed (physical/chemical, sensory, microbiological) found no differences in sensory properties or basic physical/chemical and microbiological characteristics in the products after storage under different temperature conditions for 120 days. When stored at 15 deg C, the total content of biogenic amines in samples was significantly higher than that for samples stored at 5 deg C. If the principles of good manufacturing practice are observed at all phases of the technological process, the storage temperature of 15 deg C does not represent a risk as the consequent concentration of biogenic amines and polyamines remains extremely low.

Isolates from farm to fork samples (182 isolates from 2,779 samples of raw meat and milk, meat and milk products, contact surfaces in meat and dairy processing plants) were examined genotypically (icaAB genes) and phenotypically (in vitro biofilm formation, typical growth on Congo red agar, CRA) with the aim to assess the risk of penetration of virulent strains of Staphylococcus epidermidis into the food chain. The contamination of meat and milk products was significantly higher in comparison with raw materials. The contamination of contact surfaces in meat processing plants was significantly lower than that in dairy plants. The ica genes (which precondition the biofilm formation) were concurrently detected in 20 isolates that also showed a typical growth on CRA. Two ica operon-negative isolates produced a biofilm in vitro but perhaps by an ica-independent mechanism. Samples from contact surfaces in dairy plants and milk products were more frequently contaminated with ica operon-positive strains (2.3 and 1.2%, resp.) than the other sample types (0-0.6%).

Samples of cooked sausages, ham, dry cooked sausages, and fermented sausages (n=252) were examined for soy proteins by ELISA, histochemical, and immunohistochemical methods. The results showed that the highest accuracy was achieved by immunohistochemical examination. However, in the category of cooked sausages, this result was not statistically significant. Since the results in the individual categories differed, our results demonstrate that one single method does not always provide reliable and completely objective results. Immunohistochemical methods seem to be the most suitable for the verification of the reference immunochemical method results and prevention of false results.

The purpose of this work was to examine the influence of non-coherent polarized light upon the growth and survival of Escherichia coli. Experiments were designed to test the main hypothesis that this kind of polychromatic light can produce decimal reductions in numbers of E. coli bacteria. Two strains of E. coli, one isolated from ground pork and one commercial culture (E. coli ATCC 25922), were both exposed to light for 20, 30, 40 and 60 minutes. The source of non-coherent polarized light was a Bioptron-1 lamp with the following technical characteristics: wavelength 400-2,000 nm, polarization more than 95%, and constant radiation dose 2.4 J/square cm per minute. The result for both strains showed a slight increase in bacterial count in response to an irradiation time of 20 min and decreases in bacterial counts for irradiation times of 30, 40 and 60 min without characteristics of a decimal reduction. Bacterial counts after treatments displayed a linear relationship with the total count of bacteria before treatments as well as the percentage surviving bacteria and irradiation time. Data analysis (ANOVA two factors with replication) showed that the survival of bacteria was influenced significantly by duration time, bacterial culture, and interaction between duration time and bacterial culture. Neither E. coli ATCC 25922 nor E. coli isolated from ground pork showed a decimal reduction after irradiation with non-coherent polychromatic polarized light.