Jozef Čurlej

QUALITY AND SAFETY OF RAW COW’S MILK IN SLOVAKIA IN 2011

The quality and safety of raw cow’s milk is very important for dairy companies and consumers of milk products. Due to the methods of production, it is impossible to completely eliminate contamination of milk with microorganisms, therefore the microbial content of milk is a major feature in determining its quality. Other important factors to consider include somatic cells count, veterinary drug residues, milk composition and freezing point. Somatic cells represent the udder health and can be used for monitoring of subclinical mastitis. A high level of somatic cells can increase proteolysis in milk which affects technological processes. Veterinary drugs administered to cows may lead to residues in the milk which are harmful to humans. The content of fat, protein and solids-non-fat are the main indicators used by dairies for technological purposes. In this article we discuss the quality and safety of raw cow’s milk in Slovakia during 2011. We found that 73.53% of samples tested for somatic cell count, and 84.54% of samples tested for total bacterial count, met the European Union legislation limits. We found the largest decrease in fat and protein content was during the summer period and the largest increase was in the winter period. We found that 92.14 %, 98.7% and 91.38% of samples met the limit presented in STN 570529:1999 for fat content, protein content and freezing point respectively. The percentage of drug positive samples was 0.087%.doi:10.5219/189

Occurrence of chromosomal aneuploidy in rabbit oocytes and embryos at different developmental stages.

The aim of our study was to analyse chromosomal aneuploidy occurrence in rabbit oocytes and embryos. Chromosomal analysis was done in rabbit oocytes and rabbit preimplantation embryos at 2-, 4- and 8-cell stages derived from in vivo fertilization. For mitotic cycle synchronization at the metaphase stage, 2-, 4- and 8-cell embryos were incubated in k-DMEM medium, supplemented with colcemid (1 microg/ml), for 7, 12 or 13h respectively. Success of metaphase synchronization was at values of 100, 86.1 and 92.2% for 2-, 4- and 8-cell embryos respectively. Recovery rate of analysable metaphase plates was reached at 58.8%, 83.9% and 59.8% for 2-, 4- and 8-cell embryos and 100% for oocytes. Significant difference (p < 0.01) in aneuploidy rate between oocytes (40.7%) and 2-cell embryos (62.5%) was found. These results demonstrate higher efficiency of synchronization of embryo cells at the metaphase stage, what may contribute to elevating the proportion of analysable nuclei.

Phytoestrogens dietary intake and health status of retiree from middle-notrh Slovakia region

Phytoestrogens found in foods of plant origin presents chemical substances that possess a wide range of biochemical benefits. It has been found that they contribute in different health related problems. A wide range of commonly consumed foods contain appreciable amounts of phytoestrogens. Consumption of diet rich to phytoestrogen acts as a protective factor against many diseases such as cardiovascular diseases, post-menopausal symptoms in the context of osteoporosis, cancerous illnesses of colon, prostate and breast. Three main classes of phytoestrogens covers: isoflavones, lignans and coumestans. Selected nine major phytoestrogens had been analyzed simultaneously in the same foods. Questionnaire designed to determine intake frequency as well as amount of selected foods and the most common diseases presented in the population has been used to find relationships between dietary habits and health status. Evaluation of selected goals in the present study has been realized in cooperation with 140 respondents in retired age (divided into Males - covered by 34 individuals and Females - 106 individuals), comming from middle-north Slovakia region. On the base of collected data it can be concluded, that evaluated population is presented by high values of lignans intake and particularly secoisolariciresinol, mainly caused by relative high proportion of cereals and linseed in the diet. Furthermore, the relationship between phytoestrogens intake and eating habits as well as its contribution in protection against selected diseases was demonstrated. Normal 0 21 false false false CS JA X-NONE

The effect of hFVIII transgene on the chromosomal aneuploidy rate in rabbits

The aim of this study was to compare the chromosomal aneuploidy rate between transgenic and non-transgenic rabbits derived from the F4 generation. Chromosomal analysis was carried out on bone marrow samples of New Zealand White transgenic (carrying human factor VIII gene) and non-transgenic rabbits (F4 generation) each having a different genetic background (female no. 1-3-5 line I and female no. 1-9-7 line II). C-metaphase plates were obtained from the bone marrow lymphocytes synchronized by the addition of 0.25 microg/ml colcemide. No significant difference in chromosomal aneuploidy between transgenic (61%) and non-transgenic (51.27%) rabbits of line I was observed. A higher but non-significant aneuploidy rate between transgenic and non-transgenic rabbits was found in line II, on the other hand a significant difference (P<0.05) was observed in diploidy rate. In conclusion, chromosomal aneuploidy rates in this experiment were higher than published previously in other reports.

The effect of UV-C irradiation on grape juice turbidity, sensoric properties and microbial count

In this work, we investigated the effect of UV-C radiation (254 nm) on turbidity, microbial count and sensoric properties of the grape juices treated or not treated with sulphur dioxide. The UV-C radiation is considered to be germicidal against microorganisms. This technology is routinely used to treat drinking water. Application of this method for the purpose of treating the wine was tested in few studies. These studies have shown a positive effect on the inactivation of microorganisms, but they not dealt in detail with the sensory properties of grape juice after the treatment. The main idea of using this method appears to eliminate the sulphur dioxide from wine making technology. There are people who have a genuine allergy to sulfites, and these allergies are often linked with asthma. These people have an rapid onset of symptoms when drinking liquids like wine treated with sulphur dioxide. In our work we have found that the application of this method of treating the grape juice is problematic. Intensity of UV-C radiation increases the turbidity of grape juices. This effect was observed in all grape juices with or without addition of sulphur dioxide and also in clarified or not clarified grape juices. We found that UV-C radiation negatively affect the sensory properties of grape juices. This effect was more pronounced in grape juices treated with SO2. The smell and taste were significantly negatively changed. Exposure of grape juice treated with sulphur dioxide to UV-C radiation can probably lead to arising the sulphur compounds, which affects the smell and taste of grape juices. Also, it is very likely that the negative change in taste and smell may affect the quality of produced wines. For this purpose, we do not recommend to use UV-C treatment for the grape juice treatment. It will be interesting to conduct a detailed analysis of the grape juices composition before and after UV-C radiation treatment.

Verification of animal species in ham and salami by dna microarray and real time pcr methods

Consumer protection and detecting of adulteration is very important and has a wide societal impact in the economic sphere. Detection of animal species in meat products and the use of combining different methods is one of the means to achieve relevant product status. The aim of this study was to reveal whether or not the products label clearly meets the content declared by producer. In our study, 29 samples of meat products such as salami and ham obtained from stores and supermarkets in Slovakia were analyzed to detect the existing animal species according to the product label the use of Chipron LCD Array Analysis System, Meat 5.0. Products in which the presence of non-declared animal species has been detected were subjected to testing by the innuDETECT PCR Real-Time Kit, repeatedly. The results showed that 20 (68.96%) samples were improperly labeled. From in total 14 tested ham samples 11 (78.57%) products exhibited non-conformity with declared composition. Tested salami samples (15) revealed 9 (60%) incorrectly labelled products. The results obtained by DNA Microarray and Real Time PCR methods were identical, and both methods should be extensively promoted for the detection of animal species in the meat and meat products. Normal 0 21 false false false EN-GB X-NONE X-NONE

Different RNA and protein expression of surface markers in rabbit amniotic fluid-derived mesenchymal stem cells

Over the years, there has been much confusion in defining molecular markers of mesenchymal stem cells (MSCs) for other than human species due to a lack of species‐specific antibodies. Therefore, the aim of our study was to define rabbit amniotic fluid‐derived mesenchymal stem cells (rAF‐MSCs) and to reflect upon the current identification of AF‐MSCs by providing a summary of detected surface markers in different species. The expression of rAF‐MSC surface markers was analyzed at the protein and mRNA level. Flow cytometry analyses showed that rAF‐MSCs were positive for CD29 and CD44, low positive for CD90, but negative for CD73, CD105, and CD166. Interestingly, RT‐PCR (reverse transcription‐polymerase chain reaction) exposed a discprepancy between transcribed mRNA and protein expression, as the cells expressed mRNA of all MSC markers: CD29, CD44, CD73, CD90, CD105, and CD166. Our results also confirmed the mesenchymal nature of isolated cells by morphology, ultrastructure, and intracellular marker expression profile. In addition, the expression of few pluripotency markers was also detected. We also found that passaging did not affect apoptosis and viability. Similarly, changes in karyotype were not observed during passaging. In conclusion, the provided characteristics may be used as a comprehensive set of criteria to define and characterize rAF‐MSCs, required for the identification of these cells in preclinical investigations.

Analysis of texturometric properties of selected traditional and commercial sausage

Normal 0 false false false SK X-NONE X-NONE Food texture is one of the main features that affect the consumers judgment. Instrumental texture analysis is suitable method for objective assessment of the texturometric characteristic of food. In this experimental work we have analysed textural properties of different traditional and commercial sausages originating from Slovakia. Twenty sausages were classified in four groups. Group 1 (traditional home-made sausages purchased directly from a producer), Group 2 (traditional sausages purchased from butchery), Group 3 (non-traditional sausages purchased from a supermarket) and Group 4 (non- traditional sausages purchased from a hypermarket). Once taken, samples were immediately transported to the laboratory. Samples were analysed immediately and after the storage 72 h at 25 °C and 80% relative humidity. Samples were analysed with texturometer TA-XT2 plus and we have used the Warner-Bratzler probe. The main reason of this experiment was to find differences for two selected textural parameters, firmness and toughness of the fresh and stored sausages. The average firmness and toughness of fresh sausages before storage were 1.83 kg and 12.86 kg.s -1 respectively. These values were increased after the storage. The average firmness and toughness of stored sausages were 2.74 kg and 19.23 kg.s -1 respectively. It means, storage affects the textural properties of sausages ( p <0.05). We were observed decrease of the water activity after the storage. The loss of free water was 5.1% higher in the case of commercial sausages. Also, the protein content, fat content and minerals elements content were analysed. The content of overall protein was 5.8% higher in the traditional sausages. The fat content in commercial sausages was 3.36% higher in comparison to traditional sausages. The sensory quality of traditional sausages was better than commercial sausages.

DETERMINATION OF SELECTED SPECIES TEXTURE PROCESSED CHEESE AND PROCESSED PRODUCTS DIFFERENT BATCHES UNDER DIFFERENT CONDITIONS KEEP THEM FOR EATING QUALITY

In this work we evaluated the texture of processed cheese and processed products. The products we have retained as it is assumed that they kept and used by ordinary consumers. This means that the product purchased certain period has elapsed, we included in our test conditions. Texture analysis help provide the basic methods and explaining procedures for analysis, also provide for the initiation of new types of tests or review new products and therefore be dealt with differences in the products according to specific requirements. Sensory panels also play an important role in the evaluation of food products, but the use of texture analyzer eliminates human error and tests carried out are consistent and accurate. Analysis of texture help manufacturers monitor and analyze the texture characteristics of their products. From the producers can modify the product key factors such as characteristics of the milk into cheese and can also modify manufacturing processes to the functional properties of cheese. Fulfilling the basic requirements to maintain their properties and cheese functionality.

Textural properties of chicken breast treated by different means

Normal 0 false false false CS JA X-NONE The aim of the study was to compare textural atributes of cooked chicken breast samples subjected to different storage or preparation conditions (raw meat after cooking, raw meat after freezing/subsequent thawing, after storage under modified – controlled conditions) using instrumental analysis. For this purpose, samples were subjected to texture testing by the use of Warner-Bratzler probe, to find changes in muscle hardness by determination of firmness and work of shear. As expected, various values of mentioned atributes were obtained for tested samples treated by three different ways. For statistical evaluation of the results, macro function of Exponent software and paired T test were used, statistically significant differences were taken at p <0.05. In conclussion, different forces were needed for cutting of tested samples, subjected to selected storage conditions, prior to cooking. Normal 0 false false false CS JA X-NONE