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Small mammals cause serious damage to forests but there is only little knowledge of their ecology and possibilities of plantation protection. The objective of our study was to collect information on the damage caused by rodents to plantations of forest tree species. Data were obtained from a survey conducted in 2008 that was aimed at damage caused by small mammals. Questionnaires were sent mostly to foresters engaged in the Lesy CR state enterprise. We obtained usable data from 316 foresters. The response rate was 81%. It was confirmed that rodents cause significant damage all over the Czech Republic and that the occurrence of damage cannot be easily predicted with certainty as significant damage may appear perhaps in a small part of the threatened plantations where the key conditions for small mammals have been fulfilled. The main factors which affected probability of damage include: presence of a woody species attractive to rodents; suitable structure of ground vegetation enabling the pest species to breed sufficiently during the vegetation period; and also long-lasting snow cover. The current approach of forestry practice to damage by small mammals is considerably passive and we are missing an alert system of threat to stands and a methodology of dealing with problematic situations. Most of the foresters are uninterested in small mammals and many have only very smattering knowledge of the dangerousness of individual species and their ecological requirements. The use of rodenticides is expensive and the most effective and economic measure to lower damage by small mammals is to support forest management favouring natural regeneration of forest stands.

In 2005, 2006 and 2008 the virulence of wheat leaf rust population was studied on Thatcher near-isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr10, Lr13, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Samples of leaf rust (141 in total) were obtained from different parts of Slovakia. Resistance gene Lr9 was effective to all tested isolates except three isolates from 2008. No virulence was found to Lr19 and genes Lr24 and Lr28 were also highly effective. Low incidence of virulence to Lr2a was observed. Sixty-five winter wheat cultivars registered in Slovakia were tested with seven leaf rust isolates in the greenhouse. Cultivar Bona Dea was the most resistant of all.

Nitrite is an intermediate in the oxidation of ammonium to nitrate. An elevated ambient nitrite concentration is a potential problem for freshwater fish since nitrite is actively taken up across the gills in competition with chloride. Nitrite is a well-known toxicant for fish as well as a disrupter of multiple physiological functions including ion regulatory, respiratory, cardiovascular, endocrine and excretory processes. One critical consequence of nitrite accumulation is the oxidation of haemoglobin to methaemoglobin, compromising blood oxygen transport. Nitrite toxicity to fish varies considerably and depends on a large number of external and internal factors. Among the most important ones are water quality (e.g. pH, temperature, cation, anion and oxygen concentration), length of exposure, fish species, fish size and age, and individual fish susceptibility. Chloride concentration in water is considered one of the most important factors influencing nitrite toxicity to fish. The importance of individual factors is assessed and re-evaluated continuously.

This paper has a theoretical and analytical character and it searches for the possibilities to activate the rural population by means of its social and territorial identifications. The objective of the paper is to point at some connections relating to social and territorial identity of the rural population, outlined by classic quantitative marks based upon the population up to 5 000. We base the above on the results of the representative sociological survey allowing us to analyze some of the selected problems of the social and territorial identity of the rural population, in particular its relation to residence, residential stability and autochthony, development prospects of residences, quality of social and civil relation in the rural area.

In 2008 and 2009 the effects of quassin and neoquassin (oxygenated triterpenes) on apple sawfly (Hoplocampa testudinea Klug, 1814) were studied. In the Czech Republic, monitoring was carried out in small-plot trials and in one laboratory experiment. The extract containing quassin and neoquassin was made by boiling wood chips of a tropical shrub Quassia amara L. (Sapindales: Simaroubaceae). The experimental dosages were 3, 4.5, 6, and 9.25 kg of wood chips/ha. Spray treatment with the quassia extract was carried out just before most larvae hatched out. It was statistically proven that the extract from the wood of Q. amara reduced the apple sawfly infestation of fruitlets. Extract in the dosage corresponding to 3-4.5 kg of quassia wood chips for 1/ha appeared as optimal. The efficacy of these dosages was approximately 40-50%, and the efficacy above 80% was record.

: First part of the paper assesses the physical-geographical locality factors of the agricultural production in the district of Nitra. Agricultural production in a typical high production region has been analysed (structure of the enterprises legal forms, focus of production, number of employees). The second part examines the types of the most important agricultural enterprises according to the selected economic indicators such as economic efficiency, labour productivity and relative employment. These indicators are the best ones to express the economic power of agricultural entities and farming efficiency.

An experiment was conducted to study the effect of heavy metals (Cd, Cr and Pb), soil texture (sandy, loam and clay) and incubation periods (7, 15, 30, 60, 90 and 120 days) on soil respiration (CO₂ evolution) during sugarcane trash decomposition in laboratory conditions of the Indian Institute of Sugarcane Research, Lucknow, India. Surface soils (0-15 cm) were collected from agricultural fields and crop residue of sugarcane trash (Saccharum officinarum L.) was taken in the institute farm. Crop residue (10 t/ha) and heavy metals (10, 50, 100, 1000 μg/g) were mixed and incubated at 30°C ± 2°C in an incubator. The rate of soil respiration (CO₂ evolution) decreased with increasing heavy metals concentration. During the 120 days, the toxicity decreased but still remained significant. Maximum soil respiration was recorded at 7 days of incubation period; further, it decreased with increasing incubation period. The highest drop of soil respiration rate was caused by addition of 1000 μg/g Cd, Cr and Pb levels. Clay soils evolved maximum CO₂ followed by loam and sandy soil.

The paper shows difficulties in the evaluation of the forest status when considering forests with different height structure (uneven-aged forests). It is the main problem in categorizing such forests. Concerning the actual forest management conception in Slovakia, it is assumed that the area of forests with close-to-nature management system will increase. It leads to more structured forests, as for the tree species, age, height, as well as the spatial structure. The typical vertically homogeneous forests account for only 50% of all Slovak forests, according to results from the National Forest Inventory in Slovakia (NFI SR). During the processing of NFI data the stands were divided into 2 classes as follows: (i) vertically homogeneous stands, which are classified into nine growth stages; (ii) vertically heterogeneous stands, which are classified into two growth stages (lower and advanced), and stands in the process of regeneration. New approaches are not based on the visual subjective estimation of forest homogeneity, but on objective analyses of measured values from inventory plots (tree heights, diameters, and age). The paper shows a new approach to the classification of forest stands on an example of the variability of measured heights on inventory plots from NFI.

The effects of inulin HPX and maltodextrins, and also the potentially probiotic Lactobacillus plantarum 14 strain, used separately and in combination in white cheese production, on the gastrointestinal microflora of Wistar rats was investigated. The prebiotic addition to the cheese was 2.5%, whereas probiotic and synbiotic cheeses contained at least 10⁷ CFU/g of live L. plantarum cells. The counts of Bifidobacterium sp., Lactobacillus, coliforms, and the most probable number of anaerobic proteolytic bacteria were evaluated. After a 10-day feeding experiment, significant changes (P < 0.05) were noted in the most probable number of anaerobic proteolytic bacteria spores, which was the highest in the group receiving a diet with the cheese containing the potentially probiotic strain and inulin HPX. A short-time ingestion of low doses of prebiotics or synbiotics did not alter the counts of Lactobacillus, Bifidobacterium, and coliforms in healthy rats.

Four on-farm plantations (KRNAP Vrchlabí, the Orchard of Reconciliation in Neratov, Podyjí National Park, and Šumava National Park) were successfully established in a traditional form, with large orchard trees on seedling rootstocks. Certain accessions (cultivars) for on-farm conservation in the given locality were selected, according to the incidence and presentation of genotypes in these particular areas. This information was obtained by localization of fruit trees in situ and the determination of certain cultivars. Nursery stock production for onfarm plantations is described. Because of the longevity of the plantation, seedling rootstocks were used for the production of planting materials for the on-farm plantations. Techniques of on-farm plantation establishment and orchard management are stated within the paper. Four established on-farm plantations have ensured the long-term preservation of landraces in their original areas.

Soluble lipase (Lipozyme CALB L) was immobilized by covalent bond to chitosan pellets prepared from Aspergillus niger mycelium. This immobilized enzyme was compared with commercial immobilized lipase of the same origin (Novozym 435). Novozym 435 is also lipase CALB L commercially immobilized by sorption on poly-(methyl acrylate). Novozym 435 shows much higher conversion of rendering plant fat in methanol under optimum conditions, having, at the same time, lower optimum temperature and lower stability at higher temperature. Lipozyme CALB L immobilized on chitosan leads to a low conversion, regardless its higher thermal stability. Novozym 435 gives conversion of about 50% of theoretical value, which is in good accordance with basically catalyzed transesterification of rendering plant fat described elsewhere. Lipozyme CALB L immobilized on chitosan gives conversion of about 10% of theoretical value only. The use of Novozym 435 in two-step system (enzyme-acid) seems to be more convenient compared with traditional two-step system (base-acid)

A five-year old female brown caiman (Caiman crocodilus fuscus) was admitted to a veterinary clinic because of anorexia and lethargy. Chronic deterioration of the patient's condition together with the formation of slushy stools coloured from brown to red was observed during the previous eight weeks. Physical examination showed significant apathy and cachexia. Radiographic examinations of chest and abdomen revealed no pathological findings. Initial blood tests revealed decreased hematocrit and low levels of haemoglobin. Despite treatment with enrofloxacin and intensive supportive therapy with amino acids, vitamins and mineral matter, the animal died 14 days after admission to the clinic. Post mortem examination revealed splenomegaly with a total destruction of inner organ structure together with multiple granulomas in liver and lungs. Ziehl-Neelsen staining of tissue samples from liver, lungs and spleen revealed numerous acid-fast bacilli consistent with Mycobacterium spp. Identification of isolates was carried out using PCR restriction analysis (PRA) of the hsp65 gene and DNA sequencing of the 16S rRNA gene. Two different mycobacterial isolates obtained from separate samples of liver, lungs and spleen were identified as M. chelonae and M. szulgai. This is the first report of mixed infection caused by M. chelonae and M. szulgai in a reptile.

A 14-year-old, mixed breed bitch was presented for investigation of progressive abdominal distension, dyspnea and general dullness. A large abdominal mass including numerous cystic areas was visualized in abdominal radiologic examinations. Moreover, some abdominal organs were displaced from their abdominal anatomical locations. Exploratory laparotomy revealed a uterine mass, which was removed by ovariohysterectomy. Histopathology confirmed uterine leiomyosarcoma. Clinical and radiographic examination did not reveal any evidence of metastasis two months after surgery. Canine uterine leiomyosarcomas are rare tumours, grow slowly and are not regarded as highly metastatic. In this case, removal of this huge tumor by ovariohysterectomy following laparotomy was successful as metastasis did not subsequently occur.

The domestic population of walnut (Juglans regia L.) in Serbia is highly heterogeneous as a result of many centuries of propagation from seed. This paper describes variation observed in this population over the past four decades. The date of budbreak showed a 50-day range, and the date of leaf drop a 32-day range. Average nut weight ranged from 3.3 g to 29.0 g and the kernel percentage from 26.2% to 64.3%. The number of female flowers per inflorescence ranged from 1 to 32 and the number of nuts per cluster from 1 to 15. The majority of Serbian walnut seedlings had inferior traits, although a few genotypes with excellent traits were also found. Five superior selections have been released as cultivars, and additional selections await official release. To date, over 1,000 ha of orchards have been planted in Serbia using these walnut cultivars and selections.

In the paper we evaluate the influence of crown thinning with positive selection, different intensity (moderate PRP III and heavy PRP IV) and 5-year frequency on development of growth, production, quality and leaf area index of black walnut (Juglans nigra L.) monocultures growing on the series of three permanent research plots (PRP) Sikenica (Levice Forest Enterprise, Levice Forest District) as observed in 1978-2003. The trends of development of mean stem, basal area, standing volume and aboveground dendromass (in dry matter) were mainly influenced by heavy crown thinning. The index of growth was as follows: basal area 169.01%, standing volume 262.12%, aboveground dendromass (in dry matter) 324.48%. At the age of 64 years the black walnut monocultures tended by heavy crown thinning had the following parameters: basal area 31.03 m²/ha, standing volume 463.88 m³/ha and aboveground dendromass 194.98 t/ha. Mean periodic increment reached the values: basal area 0.51 m²/ha/year, standing volume 11.48 m³/ha/year and dendromass 5.39 t/ha/year. The index of increment percent growth was: basal area + 31.75%, growing stock + 30.85% and dendromass + 0.79%, compared to the control. The total production was also significantly influenced by heavy thinning. At the stand age of 64 years the tended stands had the total basal area of 4.92 m²/ha, total volume production of 572.77 m³/ha and total weight production of 246.04 t/ha. The total mean increment of basal area is 0.67 m²/ha/year, of volume 8.95 m³/ha/year and of weight 3.84 t/ha/year, which is by 24.07%, 23.96% and 16.01% more than on the control plot. The leaf area index at the age of 64 years ranges from 6.54 ha/ha (PRP III) to 7.82 ha/ha (PRP V). Dendrochronological analyses revealed minimum widths of annual rings in the years 1952, 1961, 1968, 1971, 1975, 1981, 1983, 1985, 1993, 2000, maximum ones in 1951, 1957, 1959, 1967, 1974, 1979, 1982, 1984, 1989, 1999.

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 1409 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 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.

The German Federal Gene Bank at the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) in Gatersleben comprises ca. 148 000 accessions of crop plants and their wild relatives. Among these, material from Albania and Greece is represented with ca. 1100 and more than 2700 accessions, respectively. IPK's collection of Albanian germplasm is the world's largest collection, while IPK's Greek germplasm collection is the third largest holding of Greek crops and their wild relatives. The largest part of this material (ca. 200 and 1600 accessions from Albania and Greece, respectively) originates from two collecting expeditions carried out by Hans Stubbe, the founder of the Institute for Cultivated Plant Research, and other German collectors during the Second World War, in 1941 (ca. 700 accessions) and 1942 (ca. 1100 accessions). Stubbe's expeditions are described with respect to the regions visited, species collected, plus a comparison between the original collections and their present state in the IPK Gene Bank is provided. A formal scientific report about the results of these expeditions had never been published before. The material from these expeditions can be freely requested from the IPK Gene Bank, after signing a Material Transfer Agreement.

Soil quality is a measure of the ability of soil to carry out particular ecological and plant productive functions. It reflects the combination of chemical, physical, and biological properties. Some of the soil properties are relatively more important than the others and unchangeable. Others can be significantly changed by human activity. Nowadays, three groups of soil functions are usually defined: soil utility function (productive function, infrastructure area, source of materials); functions of soil in the environment (non-productive functions such as: water infiltration and water retention, transport of matter, buffering and sanitary functions); soil cultural function (history of nature and humans). The cultural function is, from our point of view, different from the others. The complex assessment of the soil quality is the topic of this paper and includes both the productive and environmental functions. The productive function (productive potential) of Czech soils has been long studied and is ± known. It is expressed by means of a one-hundred-point scale in the Czech Land Evaluation System. Its point values depend on different soil and local characteristics together with the natural conditions and their influence on the plant production. A similar principle was used for the assessment of the non-productive soil functions. The importance of the individual soil characteristics is defined. The values of the environmental soil function potentials are determined from the common soil characteristics and are compared with the values of the soil productive potential. Total soil quality can be then expressed as the average or as the sum of the points for all individual functions. Some selected function can be preferred by increasing its value coefficient for a specific land use area (for example, an area for obtaining underground water). Three texturally different forms of Chernozem (middle textured, clayic, arenic) which correspond to the Main Soil Units of the Czech Land Evaluation System are given as an example of the assessment. The evaluation of the total soil quality would then involve not only the agricultural and locality determined financial values but also an assessment of all environmental functions of the soil.

Estimates of the effects influencing the economics of pig production are of primary importance for breeders. For this purpose, costs, revenues and profitability were determined on the basis of individual parameters of the efficiency of tested pigs and of average commodity prices. The calculation was the result of the efficiency of actual animals and of the average and simulated prices of inputs received by producers in large-scale production operations. 136 animals, 64 of crossbred combinations (LWs × D) × (LW_D × L) and 72 of PN × (LW_D × L) were used. The total cost of 1 pig represented the costs per weaned piglet, feed and other costs; the revenues represented the actual price of a pig at slaughter. Multivariable hierarchical models were constructed to assess the relationships between the following factors: crossbred combination, nutrition and sex, ADG, number of piglets bred, CFM price and carcass price with the outcome variables: costs, revenues and profitability. The results demonstrated that the total cost of fattening pig is considerably influenced by the price of a piglet and feed, not by the price of the carcass and the growth intensity. There was no proof of a relationship between the price of a pig and reproduction and/or the price of feed. Profitability is significantly influenced by the reproduction rate, price of feed, growth intensity and revenues. The results also showed that the intensity of nutrition and the sex considerably influence the total cost of 1 fattened pig, which represents an increase in the total cost by 3.80 € in the application of ad libitum feeding techniques, and 5.39 €/pc in the fattening of barrows. The choice of a suitable combination represents a decrease in the total cost by 1.49% and an increase in revenues by 2.93%. Profitability is significantly associated with the intensity of nutrition, sex and breed. With unrestricted feeding it is reduced by 4.1%, for barrows by 6.6%, and in the use of four-breed combinations of crossbreds it increases by 4.13%.

Total number of 104 canned soft drinks collected from several regions in Turkey were analysed. The purpose of this study was to determine the levels of heavy metals in the drinks commonly consumed in Turkey. Quantitative determination of heavy metals: arsenic, copper, zinc, cadmium, and lead in all samples was carried out by ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry) method. The mean levels (± SE) of arsenic, copper, zinc, cadmium, and lead were found to be 0.037 ± 0.002 mg/kg, 0.070 ± 0.009 mg/kg, 0.143 ± 0.012 mg/kg, 0.005 ± 0.0003 mg/kg, and 0.029 ± 0.002 mg/kg, respectively, in soft drinks. Our data revealed that arsenic, copper, zinc, cadmium, and lead mean levels found in all soft drinks, collected from several regions in Turkey, were within the Turkish Food Codex (TFC) values.

Resistance of 31 winter wheat varieties (bred in 6 European countries) to Fusarium head blight (FHB) was evaluated in field trials lasting for three years (2007, 2008, 2009) after artificial inoculation with Fusarium culmorum. The data on deoxynivalenol (DON) content were supplemented by symptom scores and determination of % of Fusarium damaged grains and % reductions of thousand-grain weight and grain weight per spike due to infection. These varieties and also 120 advanced breeding lines from the Úhřetice Breeding Station, SELGEN company were examined for the presence of gibberellic acid (GA) insensitive semi-dwarfing genes to evaluate their effect on FHB. The conditions of experimental years highly influenced the performance of all characters. The highest production of DON occurred in 2008 at a high temperature and high moisture content during the infection period. In all years the moderate resistance to accumulation of DON (at the level of Swiss variety Arina) was detected in the Czech varieties Bakfis, Federer, Baletka, Samanta and Sakura. Among these varieties, Federer showed a low accumulation of DON at a relatively higher symptom expression and greater reduction of grain weight per spike, but the other four varieties and the reference variety Arina expressed resistance in all the examined traits. The varieties Pitbull, Cubus, Kodex and Bagou were found to be highly susceptible to FHB. The presence of the dwarfing allele Rht-D1b resulted in a significantly higher mean symptom score and also in a higher affection of the other traits. Nonetheless, the analysis of frequency distributions in symptom scores showed the presence of resistant lines also among the GA insensitive lines, but with a lower frequency than in the group of GA sensitive genotypes. A relatively greater effect on manifestation of the disease had plant height, and therefore it is suggested that the adverse impact of Rht-D1b on FHB resistance could be to a high degree excluded by opting for taller Rht-D1b genotypes.

Interspecific hybrids of Prunus persica, Barier, Fire, Cadaman, GF-677, and Prunus sp. hybrids and selections, MRS, NBS 540-73, and Pumiselect were evaluated for resistance to Plum pox virus. Hybrids were grafted onto trees of a peach cultivar artificially infected with PPV and evaluated for six years for resistance to the virus. The relative concentration of PPV protein was determined by semiquantitative ELISA in June every year. The presence of PPV in peach hybrids was confirmed by IC-RT-PCR in 2007-2008. The presence and intensity of PPV symptoms were evaluated monthly from May to September. The hybrid GF-677 (P. amygdalus × P. persica) was confirmed as highly resistant to PPV. Hybrids Cadaman (P. davidiana × P. persica) and Fire (P. amygdalus × P. persica) were characterized as resistant to PPV. Hybrids GF-677, Cadaman and Fire were selected as candidate sources of resistance to be crossed with peach cultivars susceptible to PPV.

In March 2010, a 3.5-month-old Korean native calf was anatomized and two nematode worms were detected in the thoracic cavity. The worms were identified and classified by light and scanning electron microscopy on the basis of features at the anterior and posterior parts of the worms. The worms were female Setaria digitata and Setaria marshalli and numerous eggs which contained microfilaria were detected in the uterus of both species. The body lengths of the S. digitata and S. marshalli were 78 mm and 117 mm, respectively. Mosquitoes act as the vector for Setaria nematodes but these are inactivated in winter in Korea. Therefore, we concluded that this case represented setariasis with congenital infection occurring during the summer prenatal stage of life.

In Pakistan citrus groves in general are facing a serious problem of decline that is attributed to different causes. The major cause, however, is the prevalence of citrus virus and virus-like diseases; Citrus tristeza virus (CTV) is of utmost concern. Although CTV has been identified and characterized on the basis of serological and physical properties, no information is available on the strains of CTV in Pakistan. The identification of CTV strains will be helpful in developing strategies to control the decline of citrus trees to a great extent. Many citrus growing countries have successfully used the technique of cross protection to minimize the drastic effect of severe CTV strains. By pre-immunization of the citrus tree with mild strains, the decline can be controlled to increase the life span of the citrus tree. In this study we focus on the possibility of establishing a cross protection technique in Pakistan against the CTV strains.

The paper points out the importance of exploring human potential not only in countryside, but also of local communities as such. We emphasize the significance of the endogenous model of territorial development for the development of countryside and human capacities as the decisive factor of territorial development. Second part of the paper focuses on changes happening in the characteristics of human potential since 1989 in Slovak municipalities. It points out to the transformation changes overcome by local communities during the important social changes. It compares situations in various types of municipalities as well as various regional differentiations in this area.

The paper deals with the study of bionomics and population dynamics of Ips typographus (L.) in the area of the Praděd National Nature Reserve (NNR). Data were collected on the basis of detected feeding marks, beetles caught in traps, and also according to the frequency of occurrence or increase in the number of standing dead trees killed by the bark beetle attack in localities where sanitation felling was not performed. Finally, evaluation of the present condition of forest stand and population dynamics of Ips typographus was carried out. The results showed that the stands currently occur in the stage of disintegration when the role of the bark beetle is irreplaceable. Based on the research findings, the management of the bark beetle was proposed that would enable to achieve so-called regulated disintegration of natural spruce forests in the area of the Praděd NNR.

The Mixolab device in view of the characterisation of the thermo-mechanical behaviour of ten different flours, and establishing the correlations between the rheological parameters of wheat flour supplemented with different additives such as fungal α-amylase, fungal hemicellulase, and fungal xylanase weres exploted. The rheological measurements were performed using the Mixolab, Alveograph, and Rheofermentometer. Our results indicated significant positive and negative correlations between the parameters investigated. The changes of the Mixolab curve trend depended on the amylase doses. Significant correlations were established also between the Mixolab parameters and the results of the baking tests; the β slope, C2, C3, and C4 were positively correlated with the specific volume of the bread. Taking into account the results obtained, we may conclude that Mixolab is a complex device that renders the evolution of the bread during the entire technological process, from the dough making to the starch retrogradation.

Polyclonal antibodies were raised against six immunogens (three native and three thermally treated casein fractions: a+b-casein, k-casein and whole casein). Using these antibodies the procedures of an indirect competitive enzyme immunoassay (ELISA) were constructed, optimised and characterised for determination of each immunogen. It was found that ELISA of caseins is very specific without any interferences of whey proteins and with proportionally low cross-interactions between caseins. Detection limits for a-, b-, and k-caseins and whole casein were 110, 49, 58 and 505 ng/ml, respectively. The coefficient of variation was lower than 12% in intra-assay and lower than 9% in inter-assay. The developed ELISA format was used to study changes in casein immunoreactivity during heat-treatment and proteolytic hydrolysis. Heating below 100°C did not change the milk immunoreactivity but heating above 100°C caused its significant changes. Depending on type of proteolytic treatment (with enzyme preparation Pancreatin or with microbial cultures of Lactobacillus helveticus and Lactococcus) a decrease and an increase in casein immunoreactivity were observed. While Pancreatin reduced the casein immunoreactivity substantially (5-1000 times in dependence on the casein type), the more gentle proteolysis by bacteria caused not only its reduction (even 100 times at k-casein) but also its increase (1.5 times at a-casein).

The microwave power is a parameter greatly influencing the rate of heating. Several authors reported on certain differences between the rated power output as a parameter used by oven manufacturers in the labelling of ovens, and the power actually delivered to the heated product. A review of the respective information is given in this article together with the results of own experiments following the influence of the oven type and the heated substance parameters on the power actually absorbed in the substance volume during its heating. As the heated substance, water and solutions of NaCl and sucrose of different concentrations were used. For the heating, four types of domestic microwave ovens and glass and plastic containers, were used. The decreasing of the efficiency of heating with the decreasing volume of the heated substance and a certain relation between the rate of this decrease and the types of oven and of substance was estimated. With the small cavity ovens, a lower rate of the decrease of the absorbed microwave power with the decreasing volume of the substance was found as compared to the large cavity oven. A certain influence of other technical oven parameters is shown in the comparison of the tests results with the ovens of the same rated power and the cavity volume. In addition to the substance volume, also its dielectric properties probably influence the microwave power absorbed in small samples during the heating. No simple dependence can be seen on the basis of the tests results between the type of container used in the tests and the power absorbed in the heated substance.

Coagulated gel was characterised using an oscillation rheometer Rheostress RS 150. The influence was monitored of the additions of rennet and CaCl2, of temperature, and of high-pressure treatment on the properties of coagulated gel. Parameters of coagulation were assessed, i.e. elastic modulus G', the time of the start of coagulation t0, and the time constant of congealation τ. In monitoring the influence of increasing additions of rennet and CaCl2, and of temperature increase, it was found that the time of the start of coagulation t0 and the time constant of congealation t decreased. The limiting shear storage modulus G'max was practically constant at various amounts of CaCl2 and was moderately decreasing with increasing temperature and rennet addition. This effect was possibly caused by the fact that the limiting value is a regression parameter extrapolated to infinity. The real values of the modulus for a given time increased with increasing levels of calcium chloride added. Milk treated by the pressure of 600 MPa for 10 min formed, during coagulation, a more solid gel, the shear storage modulus being, almost by 100% higher as compared with untreated milk. Value of the time constant of congealation was practically halved.