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Shelf life extension of fresh sea buckthorn berries (Hippophae rhamnoides)
2006
Seglina, D. | Karklina, D. | Dukalska, L.
Sea buckthorn berries are one of the most important sources of vitamins, minerals, organic acids, polyphenols and other biologically active substances in human nutrition. The shelf life of fresh chilled berries does not exceed one week. The venues of research were Fruit and Berry Processing Centre of the Dobele Horticultural Plant Breeding Experimental Station and Packaging Material Testing Laboratory of the Faculty of Food Technology, Latvia University of Agriculture, from August until October 2005. Two most popular sea buckthorn cultivars in Latvia - 'Avgustinka' and 'Prozrachnaja' - were used for the study. Sea buckthorn samples were packed in ready-made PET/adhesive/PP containers supplied by 'Huhtamaki'. Gas mixture with initial composition of 10% of O2, 10% of CO2, 80% of N2 and ambient air as control were used. Containers were sealed on the packaging equipment 'TECNOVAC Pratica'. Packed sea buckthorn samples were stored at +4+-1 deg C temperature for 50 days. The aim of this study was to clarify the effect of the initial concentration of gas mixture in the package made from plastic of high barrier properties on the quality of fresh sea buckthorn berries during storage time. The results showed that shelf life of fresh sea buckthorn berries without any significant quality changes can be extended till 30 days by packaging in containers with high barrier properties and air ambiance.
Mostrar más [+] Menos [-]Determination of tryptophan metabolites in porcine adipose tissue: a preliminary report
2006
Zamaratskaia, G. | Jastrebova, J.
Tryptophan is a precursor for the production of skatole and indole in the large intestine of pigs. Accumulation of these compounds in adipose tissue causes on objectionable odour in meat from entire male pigs. Potential market impact illustrates the importance in developing an accurate method of determining skatole and indole content in adipose tissue. In the present study, a method is described for determination of skatole and indole concentrations by liquid chromatography combined with mass spectrometry (LC-MS) using atmospheric pressure chemical ionization (APCI). The optimization of chromatographic and APCI conditions is reported. This method showed excellent linearity over the concentration range tested (from 10 to 1000 ng mlE-1 of liquefied fat for both skatole and indole).
Mostrar más [+] Menos [-]Application of quantitative risk assessment in catering area
2006
Melngaile, A. | Karklina, D.
Company - oriented risk analyses is the necessary precondition to establish, validate and improve HACCP procedures in catering enterprise. In catering area no microbiological criteria exist for ready-to eat food in both European and Latvian level. The objective of the study was to apply risk assessment approach to evaluate microbiological risks during food preparation processes in school catering establishments. The aim of the author's research was to assess the level of microbiological contamination of food as well as the changes of microbial contamination during technological processing of food to motivate the necessity for controlling of food contamination levels in frame of HACCP procedures. It was concluded that no significant risk in consumption of cooked minced meat food if cooking temperature is adequate and food is stored at correct temperature after cooking. The storage of salads in ambient air temperature causes a significant increase of bacterial contamination due to high initial contamination level that may create a serious risk in case of pathogenic bacteria. On the basis of research it was concluded that microbiological investigation should be a recommended way to test step-by step the performance of technological processes because the hygiene situation is specific to each catering establishment and safety of the end-products may vary considerably. Microbiological testing of food and environmental samples could be a helpful tool for development and validation of HACCP procedures to assess potential risks and to establish critical limits for managing of technological steps in school food service area.
Mostrar más [+] Menos [-]Forest clear-cut mapping in Latvian and Estonian boundary area with Landsat Thematic Mapper satellite images
2006
Budenkova, J.
The most obvious application of satellite images in forestry areas and generating forests maps with particular emphasis on identifying temporarily non-forested areas and mapping forest clear-cuts. The aim of this paper was to investigate the influence of attributes describing forest clear-cut patch size, patch shape, and habitat conditions on classification results and map forest clear-cuts in Latvian and Estonian boundary area. The satellite images used were medium spatial resolution Landsat Thematic Mapper satellite images made in plain snow cover conditions in late winter. The boundary area was represented by Aluksne region in Latvia and by Voru County in Estonia. Clear -cut areas as changed areas in forests were discerned from non-changed areas with image differencing method that has proved itself as one of the most often used methods in land use and land cover change detection.
Mostrar más [+] Menos [-]Change of forest land use - problems, losses, values
2006
Bara, G.
Forests and possibilities for forest land use have always played a very significant role in Latvia, gathering important experience in the course of time that can be analysed and used to improve the existing laws and regulations on the basis of the acquired results. the territory is characterised by a high percentage of forest coverage and its potential to increase up two thirds of the terrestrial area of the country. In the current economic, social and ecological situation it is important to provide a scientific explanation for the future fluctuations of forest resources balance due to natural and artificial transformation of lands - what is discussed in this article?
Mostrar más [+] Menos [-]Indications of pupils' competitiveness
2006
Kalnina, I. | Katane, I.
The ongoing globalisation and integration processes increasingly influencing the different social processes, including the situation in labour market have raised up the topicality of the necessity in education to develop competitiveness of the society in general as well as in every individual. Several documents of international and national importance provide evidence for such an assumption. Education is to become preconditions, process, result, and tool for the development of competitiveness of an individual. This promotional process should be based on scientific research as well as become a part of the duties of every educator. Therefore it is important to scientifically substantiate the conceptual notion 'competitiveness', differentiating between its structure, components, and features. The authors of the present paper have found the theoretical background: 1) theoretical substantiation of the concept of competitiveness in the researches by scientists from Western countries and Russia; 2) appropriate definitions of the concept 'competence' for research of pupils' competitiveness.
Mostrar más [+] Menos [-]Training academic writing in university students
2006
Luse, N.
Training academic writing is proposed as a topical subject within the teachers' education study programme on graduate level at Latvia University of Agriculture. In order to promote the development of students personality self-actualization, we are called for introducing new digital technology as teaching-learning method contributing to opening up opportunities in training academic writing at University. How can we use the digital environment for developing formal academic writing technique in our students? The main argument is that digital environment is a key factor for changes in the teaching-learning process and organization of Teachers' Education study programme curricula as the traditional academic print world is changed. Students involved in the Teachers' Education study programme at University are using Web conducting their learning process. Academic writing as a part of learning process at University is based on cognition and activity. We propose to define the training of students' academic writing as a learning process transforming the student's knowledge in unity of two positions: curricular academic writing and informal academic writing. We propose three criteria towards the students' academic writing as heuristics, self-dependence and collaboration. How can we help our students to promote academic writing by using the digital environment? How can we help them differentiate between the appropriate and inappropriate use of information found on the Web and understand what plagiarism is and how is to be avoided?
Mostrar más [+] Menos [-]Environmental aspect of dialogue educational method in Latvia rural music school
2006
Cernavska, G.
In XX century, educational dialogue is researched as educational and pedagogical method. The rural music schools of Latvia are good basis for scientific investigation. The aim of the research is to study situation of the educational dialogue in Latvia rural music schools and to analyse pedagogical aspects and authority, constructing progressive environment in understanding between individuals. A two thousand year's dialogue shows perspective way for best communication and cooperation. Dialogue idea in XX century philosophical and pedagogical theories is analysed in M. Bbuber, M.M. Bakhtin, P. Freire and N.C. Burbules works, and they have played an important role in the development of dialogue theory as a pedagogical problem. Dialogical interaction can provide to higher motivation of ensemble play lessons and to solve transportation and large way distance difficulties in Latvia rural areas.
Mostrar más [+] Menos [-]The importance of aquaculture in the South-Eastern Anatolia Project in Turkey
2006
Canyurt, M.A.
The South-Esatern Anatolia Project (GAP) is a multi-sector and integrated regional development project in Turkey. The project area covers 9 administrative provinces - Adiyaman, Batman, Diyarbakir, Gaziantep, Kilis, Mardin, Siirt, Sanliurfa, and Simak - in the basins of the Euphrates and Tigris. The GAP planned in the 1970s consists of projects for irrigation and hydraulic energy production on the Euphrates and Tigris rivers. The development program encompasses such sectors as irrigation, hydraulic energy, agriculture, fish farming, rural and urban infrastructure, forestry, education, and health. This project envisages the construction of 22 dams and 19 hydraulic power plants and irrigation of 1.7 million hectares of land. The total cost of the project is estimated as US $ 32 billion. The construction of several dams will cause an increase in total capacity of more than 600 000 tons of fish in the region. Aquaculture will be an important source of income for the people and the economy of the country, a sum of US $ 1.8 billion of income will be obtained each year.
Mostrar más [+] Menos [-]Acquisition of some meteorological parameters for the development of solar collectors
2006
Kancevica, L.
In order to get maximum economic effect, when setting a solar collector in a peasant yard, it is important to choose the correct place. The yield of obtained heat energy will be at its maximum, if the temperature of surrounding air and solar radiation are higher by the relative humidity of the air - lower. To define these parameters, a special device 'Meteorological Device' (MD-4) was developed. The device was supplied with a mechanism which tracks the sun all day round. So the direct solar radiation on the surface perpendicular to the sun beams was measured. The second measuring of the solar radiation was made in relation to the surface, which was perpendicular to the sun beams only at the middle of a day time. For the measuring of the air temperature and relative humidity, corresponding sensors were used. In every 15 minutes the data of these four meteorological parameters were automatically measured and the results were saved into a logger - the device for data accumulation. After a certain period of time the information was brought into the memory of a computer and analysed.
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