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Root vegetables from Latvia: quantitative analysis of trace elements Full text
2012
Vincevica-Gaile, Z., University of Latvia, Riga (Latvia) | Klavins, M., University of Latvia, Riga (Latvia)
Food and drinking water are the main sources of trace and major elements. Besides the elements that are vitally essential for living organisms and human health, food may contain the traces of potentially toxic elements. Environmental site specific impact is one of the influencing factors of elemental content in plants that is important issue also for quality of food crops. Quantitative content of several trace elements (e.g., Al, As, Cd, Co, Cr, Cu, Ni, Pb, Zn) detected in food crops reveal environmental background levels as well as it can be associated with unexpected food contamination. Current study involves quantitative analysis of more than 200 root vegetable samples (onions, carrots and potatoes) grown and collected in Latvia in the harvesting season of 2010. Within this study the quantitative analysis of vegetables for 9 elements (As, Cd, Co, Cr, Cu, Ni, Pb, Se, Zn) was performed. After the wet digestion of samples, the quantitative analysis was done by using inductively coupled plasma mass spectrometry (ICP-MS). Obtained results revealed wide ranges of trace elements in root vegetables, including potentially toxic elements. Comparison of element content in edible parts of vegetables and potato peel showed that a great part of elements (e.g., As, Co, Cr, Pb) is concentrated in peel; however, some elements (e.g., Cd, Se, Zn) are taken up by plants, and therefore may contaminate food more easily. Element transfer routes and their biochemistry is a complicated issue that is affected by natural environmental factors as well as by anthropogenic activities.
Show more [+] Less [-]Rheological properties of triticale (Triticosecale wittmack) flour blends dough Full text
2012
Sabovics, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
Triticale is an amphidiploid hybrid between wheat and rye having protein-rich grain. For expanding the range of bakery and pastry production in the world there are being developed various recipes for product enriching with fibre, especially b-glucan, proteins, vitamins and other nutrients for a healthier diet. It can be done making a flour blend from whole grain triticale, rye, hull-less barley, rice and maize flour. The aim of research was to evaluate the rheological properties of dough made from different cereals flour and flour blends. Whole grain flour of triticale, rye, hull-less barley, rice, maize and flour blends were used in this research. Flour blends were made from triticale in a combination with other flour (whole grain rye, hull-less barley flour, rice and maize flour) in various proportions. Wheat flour (Type 405) was used as a control. Rheological properties of mixed flour dough were studied using Farinograph (Brabender Farinograph-AT, GmbH and Co. KG, Germany). Moisture content of flour and flour blends was determined using AACC method 44-15A. Water absorption and dough development time decrease, but dough stability, time of breakdown and farinograph quality number increases, increasing proportion of other flour in triticale flour. The flour blends need less time for dough development comparing with triticale flour. Enriching triticale flour with whole grain rye, whole grain barley, rice and maize flour in various proportions made triticale flour dough more rheologically stable during mixing.
Show more [+] Less [-]Influence of packaging conditions on the quality of pickled venison Full text
2012
Silina, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gramatina, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Venison is well known as a traditional meat type in Europe, and it is lower in calories, cholesterol and fat content than common cuts of beef, pork or lamb. The aim of the current research was to determine physico-chemical parameters such protein, fat, pH, moisture content as well microbiological quality of pickled venison during storage. Beef as a control was analyzed for comparison of obtained results. The meat (2×3×2 cm) pieces were pickled in vinegar marinade (composition: tomato sauce, mayonnaise, vinegar, lemon, onion, parsley, paprika, basil, black pepper, rosemary, salt) at 4±2 °C temperature for 48±1 h. The marinated meat was placed in polypropylene trays and hermetically sealed with high barrier polymer film under modified atmosphere (C02 40%+N2 60%) without and with iron-based oxygen scavenger sachets (Mitsubishi Gas Chemical Europe Ageless®). As a control, packaging in air ambiance packed pickled products was used. During storage time, the moisture and protein values significantly (p is less than 0.05) decreased and pH, fat content and colony forming units significantly (p is less than 0.05) increased in the pickled venison samples of all packages. Slower changes in pH of pickled venison and in the protein and moisture content of marinated beef were observed in modified atmosphere with oxygen scavenger during storage.
Show more [+] Less [-]Fatty acid composition of the meat of elk, deer, roe deer and wild boar hunted in Latvia Full text
2012
Strazdina, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jemeljanovs, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Sterna, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
Every autumn and winter period, game animals - elk (Alces alces), deer (Cervus elaphus), roe deer (Capreolus capreolus) and wild boar (Sus scrofa scrofa) - provide an excellent input in the diversification of many consumer meals. In the recent years, consumption and assortment of game meat products has significantly increased. At the moment there are only few biochemical composition investigations of the game meat. The meat of wild animals is more favourable for human health, because it has a lower content of saturated fatty acid, but a higher content of protein. Therefore the aim of our investigation was to compare biochemical composition of the game meats hunted in Latvia. Investigations were carried out in different regions of Latvia. In the studied samples, protein, intramuscular fat, fatty acids and cholesterol were determined. The biochemical analysis of 54 samples was carried out. The results of the analysis showed that protein content in all types of the meat samples was 22.36 - 22.92%, which is not statistically significant. The fat content, on the other hand, was significantly lower: 1.33 ± 0.88% in elk meat samples, and 1.59 ± 0.59% in roe deer meat samples. Content of cholesterol varied from 64.41% to 95.07% in the ruminant meat samples of different species. From the dietetic point of view, the meat samples of roe deer had the best composition of fatty acids.
Show more [+] Less [-]Antimicrobial resistance of animal pathogens 2006-2009 in Estonia Full text
2012
Aasmaee, B., Estonian Univ. of Life Sciences, Tartu (Estonia) | Kalmus, P., Estonian Univ. of Life Sciences, Tartu (Estonia)
The present study describes situation of antimicrobial resistance of animal pathogens and resistance trends in Estonia in years 2006-2009. Bacterial strains isolated during period 2006-2009 were Escherichia coli (E. coli), Enterococcus faecium (E. faecium), Enterococcus faecalis (E. faecalis), collected from healthy pigs faeces as well as from diagnostic submissions of pig samples. Staphylococcus aureus (S. aureus) isolates originated from cows with clinical mastitis and Staphylococcus pseudointermedius (S. pseudointermedius) isolates from dogs with pyoderma or otitis externa. Antimicrobial susceptibility was detected by microdilution method. Normal enteric microflora from health y pigs had resistance against streptomycin, tetracyclin, sulfametoxazol and trimethoprim. E. faecalis and E. faecium were resistant to erythromycin, tetracyclin, streptomycin and kanamycin. Multiresistance occured mainly against kanamycin, streptomycin and tetracyclin. E. coli strains isolated from pathological material showed high resistance to ampicillin, tetracycline, streptomycin, sulphonamides and trimethoprim. Multiresistance was detected between 60–73% during study years. In 2009, one ESBL (extended spectrum betalactamase) producing isolate was observed. S. aureus strains isolated from clinical mastitis samples were mainly penicillin resistant (58–86%). Meticillinresistant S. aureus was not found during the study. In 2009, resistance to lincomycin (30%) and fucidinic acid (22%) was detected. In S. pseudointermedius strains isolated from canine skin samples the prevalence of resistance to penicillin as high as 53–81% was found. Multidrug resistance was relatively stable being 38% in 2006, 29% in 2007 and 25% in 2009. In conclusion, antimicrobial resistance of animal pathogens in Estonia was high. Further improvement of prudent use of antimicrobials and infection control is needed.
Show more [+] Less [-]Aortic lumen diameter and blood pressure changes dynamics after replacing aorta abdominalis with prosthesis Full text
2012
Malniece, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Auzans, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Drevinska, K., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of this study was to find out the biointegration of innovative vascular prosthesis, made in Riga Technical University (RTU), in dog’s abdominal aorta. The research is being performed in Veterinary Medicine Faculty of Latvia University of Agriculture since July 19. 2011. We used 9 female gender and 1-3 years old Beagle dogs in this study. The research is approved by the Latvian Republic Food and Veterinary Service. The study is carried out in the frame of European Social Fund co-financed project ‘Establishment of interdisciplinary research groups for a new functional properties of smart textiles development and integrating in innovative products’ (ESF No. 2009/0198/1DP/1.1.1.2.0./09/APIA/VIAA/148). 5-8 mm in diameter, 8 mm - 18 mm in length RTU produced aortic grafts were implanted retroperitoneal in dogs. Before the surgery the diameter of abdominal aorta was measured in cross sections, afterwards – cranial and caudal from the prosthesis, as well cross-section diameter of vascular graft was measured. Blood pressure was measured before the surgery and after the procedure on regular basis. Results are the following: there are no significant differences in aortic and graft diameter before and 1-2 months after the operation, there are no significant differences in systolic and diastolic blood pressure before and four months after the surgery at significance level α = 0.05. The study shows that the innovative aortic prostheses don’t change in diameter, and surgery like abdominal aorta transplantation doesn’t cause significant variations in blood pressure. The study is being continued to find out later reactions to synthetic vascular graft.
Show more [+] Less [-]Dynamic model of biochemical network of Zymomonas mobilis adaptation for glycerol conversion into bioethanol Full text
2012
Odzina, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
One of the biodiesel production problems is occurrence of a significant quantity (about 10%) of the by-product – glycerol. This problem is offered to solve by adaptation of bacteria Zymomonas mobilis, which is notable for ethanol production facilities. To be able to process glycerine into ethanol using Z.mobilis bacteria, the bacteria must be modified. At the same time, computer modelling analysis is required to assess specific modification affectivity in interconnection with other processes in bacteria. Computer model results of simulated experiment to understand and predict that the cells and biological processes are essential to reduce the number of experiments. This in turn reduces the necessary financial resources and time, bio-medical biotechnology, pharmaceutical and environmental problems. The model describes conversion of glycerol into bioethanol in Z.mobilis bacterial cell. First phase of model creation is creation of a structure model based on biochemical reactions using computer software CellDesigner. On the second phase of model creation, kinetic parameters which are available in literature were identified. Using the databases KEGG, SABIO-RK, BRENDA, reactants, kinetic parameters and reaction equation types were defined. Dynamic model of Z. mobilis biochemical network was created using computer software Copasi. The dynamic model describes conversion of glycerol into bioethanol in Z.mobilis bacterial cell. In this time simulation data of the computer model of natural organisms are not to confirm laboratory experimental data. Simulation data of the computer model are not correct to prevent this problem is required parameter estimation in computer software COPASI.
Show more [+] Less [-]Heterobasidion spp. in Picea abies understory: incidence and impact on radial growth of trees Full text
2012
Gruduls, K., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Gaitnieks, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Donis, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Liepa, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Heterobasidion spp. is an important pathogen in the Northern Hemisphere, causing root and butt rot mainly in conifers. Norway spruce (Picea abies (L.) Karst.) is one of the most common tree species infected by Heterobasidion spp. In Latvia, 22.9% of Norway spruce stumps are infected. Heterobasidion spp. decreases timber quality, but what impact it has on Norway spruce growing in understory of dominant stand is not known. The aim of the study was to evaluate incidence of Heterobasidion spp. on understory Norway spruce in Myrtillosa forest type and impact on radial growth of trees. In autumn of the year 2011 in a sample plot located in forests of Kalsnava district a total number of 258 trees were examined for presence of Heterobasidion spp. Results showed that 54% of examined trees were rotted. In 30% of trees Heterobasidion spp. was detected. It is concluded that Heterobasidion spp. does not impact radial growth on understory Norway spruce trees.
Show more [+] Less [-]Distribution and status of common juniper (Juniperus communis L.) in Lithuanian pine stands Full text
2012
Vaitkeviciute, R., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Distribution and status of common juniper (Juniperus communis L.) in Lithuanian Pine stands are investigated in the study. The research was conducted in pure pine stands on sites with normal humidity and poor fertility in South – South Eastern parts of Lithuania. 40 stands were selected for data collection. Temporary rectangular sample plots with area of 10 square m were selected. According to method of underbrush evaluation, diameter root neck level, height and state index was measured for 3 juniper individuals located near the centre of sample plots. The number of sample plots depended on the area of each stand, but it was not lower than 10 in each stand. Average diameter of junipers was 3.03 cm, average height – 2.03 m. It was determined that average density of juniper individuals is 5055 individuals per hectare, and separately in vacciniosum and vaccinio – myrtilosum forest types - 4844 and 5282 individuals per hectare respectively. Average state index of juniper individuals in 6 grade scale was 2.96, which is near to grade 3 (slightly damaged). Results of the study show that distribution, status and dendrometric characteristics of junipers are different in adjacent regions of pine provenance.
Show more [+] Less [-]System analysis of productivity and cost of stump extraction for biofuel using MCR 500 excavator head Full text
2012
Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Zimelis, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
In the 30ies of the 20th century stump extraction was identified as one of the most prospective technologies of forest sector to secure deliveries of solid biofuel. Now we are returning to the same challenges having the same targets – to secure energy independence and competitiveness of forest sector. MCR 500 is the prototype of combined stump extraction and mounding bucket for caterpillar excavator produced in Latvia by the LSFRI Silava and engineering company Orvi SIA. The device is made for extraction of stumps with diameter up to 50 cm. Additional benefit of the device is its ability to prepare soil for the forest regeneration by making mounds. The article summarizes results of productivity trials of stump extraction using the MCR 500 head and following forwarding of the material. Data from earlier studies are used to characterize comminution and road transport of stumps and chips. In total 3.5 ha were extracted during the studies. A harvested amount of stumps was estimated using biomass equations. It will be updated in further comminution studies. Average stock of extractable biomass (stumps and coarse roots) on the experimental sites was 28 tons ha-1. Productivity of stump extraction was 2.4...3.4 tons per efficient hour. Consumption of efficient time for scarification of soil was 3.4...4.3 hours per ha. Forwarding took 30 min per load (2.6 tons per efficient working hour). Prime cost of chips according to biomass equations is 9.78 Ls LV mE-3, according to expert judgement based harvested stock is 6.38 Ls LV mE-3.
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