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Assessment of apple cultivar quality and selection of the most suitable apple cultivars for fresh cut salad production
2011
Krasnova, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Seglina, D., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Juhnevica, K., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Kviesis, J., Latvian State Inst. of Fruit-Growing, Dobele (Latvia)
Apples (Malus domestica L.) are the most consumed fruits in Latvia. Apples are used as one of ingredients for the fresh cut fruit salad preparation. The evaluation of physical, chemical and sensory properties is important; they could influence the nutritional value of fruit salads. The objective of this research is to select for fresh cut salad production the most appropriate apple cultivars grown in Latvia and evaluate their physical, chemical and sensory properties. Ten commercial apple cultivars grown in Latvia were selected for experiments: ‘Zarya Alatau’, ‘Saltanat’, ‘Belorusskoe Malinovoe’, ‘Auksis’, ‘Antei’, ‘Sinap Orlovskii’, ‘Orlik’, ‘Korichnoe Novoe’, ‘Alesya’, ‘Kovalenkovskoe’. The research was carried out in the Latvia State Institute of Fruit Growing (LSIFG), the years 2010 – 2011. The apple physical indices (average mass, diameter of fruit, flesh consistency and colour) and chemical parameters (total sugar, soluble solids content, titratable acidity ratio between soluble solids and titratable acidity) were analyzed as well. The sensory properties were determined using quantitative descriptive analysis and affective method by hedonic scale. The physical and chemical properties of fruits were analyzed and for fresh cut fruit salad production as the best the following apple cultivars: ‘Zarya Alatau’ and ‘Sinap Orlovskii’ were selected; however, the cultivars ‘Antei’, ‘Auksis’ and ‘Alesya’ could be successfully used for mentioned aim as well.
Mostrar más [+] Menos [-]Influence of different yeast strains on the production of volatile compounds in fermented apple juice
2011
Riekstina-Dolge, R., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Seglina, D., Latvian State Inst. of Fruit-Growing, Dobele (Latvia)
Aroma forming volatiles are important components of fermented beverages. The aim of current research is to evaluate the influence of different yeast strains on the volatile compounds of fermented apple juice of the variety ‘Lietuvas Pepins’. Apples were harvested in the Latvia State Institute of Fruit Growing. Apple variety ‘Lietuvas Pepins’ juice was fermented with four different commercial yeast strains - Saccharomyces bayanis yeasts ‘EC-1118’, ‘Cider yeast’, Saccharomyces cerevisiae yeasts ‘71B-1122’ and ‘K1V- 1116’. Fermentation was performed in laboratories of Latvia University of Agriculture, Faculty of Food Technology. Volatile aroma compounds of apple juice, yeasts and fermented juice were determined. Extraction of aroma compounds was performed using solid phase microextraction (DVB/Car/PDMS fibre). Analysis of volatile aroma compounds was made using a Perkin Elmer Clarus 500 GC/ MS. The data obtained in the present study shows the influence of the yeast strain on the final chemical and volatile composition. The main group of volatiles in juice was esters, whereas in fermented juices – alcohols. The highest percentage of esters was determined in juice fermented with ‘Cider yeast’ whereas the highest percentages of alcohols – in juice fermented with yeast K1V-1116 and also free terpenes, associated with the floral note. The 71B-1122 strain produced the highest amount of identified volatile compounds. The strains potentially producing a higher number of volatile compounds could contribute to a more complex aroma of the final product, due to their potential ability to utilize and transform numerous apple must precursors.
Mostrar más [+] Menos [-]Consumers' attitude to milk pomade sweet - sherbet consumption and its quality on the sales network of Latvia
2011
Ungure, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Muizniece-Brasava, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dukalska, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Sherbet with crunchy peanut chips could be classified as milk pomade. It is one of popular sweets in Latvia produced by Joint-stock Company Laima, which is one of the oldest producers of sweets in the Baltic States. Freshly made sherbet is soft and savoury but after several days’ storage at the open air gradually hardens, the product loses eye appeal, taste and becomes unmarketable. This problem limits the shelf life, so sherbet with crunchy peanut chips can be marketed only at the local market. The target of this study was to clarify the situation on the market in Latvia and to examine an issue of Latvian consumers’ awareness of milk pomade sweets – sherbet quality indicators, packaging and its presentation to consumers, as well as the sherbet market expandability. A questionnaire was developed – 800 respondents answered on the 14 questions – how well-recognized the milk pomade sweet – sherbet is, what the main features for this kind of sweets selection by consumers are, which quality indices are important for consumers. One of most important questions was to get know the consumers opinion about sweets, mainly sherbet possible packaging kind and the market turnover. Summarizing the questionnaire data, the response from consumers in Latvia was heartening – they like milk pomade candies. As a primary quality defect the hardness of sherbet was mentioned. Eliminating this main failing of quality, the demand of sherbet on the market could rise, as well the product marketing opportunities will grow.
Mostrar más [+] Menos [-]Development of experimental equipment for vegetable oil fuel research
2011
Birkavs, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dukulis, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
The European Parliament and Council Directive 2003/30/EK ‘On the promotion of the use of biofuels and other renewable fuels for transport’ determines that pure or straight vegetable oil, produced from oil plants by pressing, extracting or comparable procedures, crude or refined but chemically unmodified, compatible with common engines, and corresponding to emission requirements, is also considered as biofuel. The biggest problems imposed by these conditions are directly associated with the carrying-out of the emission requirements, because when using vegetable oil as a fuel, usually increases the composition of the solid particles and nitrogen oxides in exhaust gases, that not only adversely affect the environment, but also is a serious threat to human health, and as a result trying to save the world from the global warming, human health continues to deteriorate. It is therefore necessary to carry out studies and find solutions to reduce harmful emissions from diesel engines when using vegetable oil fuel. For more qualitative and effective research on vegetable oil fuel emissions, the equipment for vegetable oil fuel testing has been developed. This equipment allows fast checking of theoretically proposed hypotheses and detailed calculations for vegetable oil fuel combustion processes and objective data acquisition. The equipment consists of the classic diesel engine adapted for work with vegetable oil and is equipped with several high-precision devices to get and store the measuring data. During pilot tests the optimal measuring modes (engine rotation frequencies, number and duration of repetitions) for further research are estimated.
Mostrar más [+] Menos [-]Evaluation of study programme external quality
2011
Sproge, S., Latvia Univ. of Agriculture, Jelgava (Latvia)
Quality assessment of a study programme is a topical issue in the single education area. Quality is not a unequivocal term in higher education area, which lends itself to many understandings and interpretations according to different criteria. The best practice of software engineering may be applied for the study programme evaluation if by analogy it is viewed as software product. Study programme similar to software product has internal and external quality. Students as direct users of the study programme may be engaged in the evaluation of its external quality, in case the evaluation of internal quality of the study programme is mainly based on internal resources of a higher education institution. The paper provides the methodology for evaluation of external quality of a study programme based on software product quality model and quality assurance standards. Approbation of the methodology was started in 2009 at the Faculty of Information Technologies, where students evaluated external quality of undergraduate study programmes. Results obtained during the approbation lead to the conclusion that the chosen methodology ensures significant information for the enhancement of quality of a study course and simultaneously the entire study programme.
Mostrar más [+] Menos [-]An agent-based hybrid intrusion detection system
2011
Paulins, N., Latvia Univ. of Agriculture, Jelgava (Latvia)
Intrusion Detection Systems is defined as a component that analyses system and user operations in computer and network system to protect it from possible intrusions. Current intrusion detection technologies have several shortcomings. Applying mobile agents to intrusion detection design is step forward on better intrusion detection. Mobile-agent based distributed intrusion detection systems are very promising for the following reasons: reduction of data movement, load-balance, flexibility, fault-tolerance, detection of distributed attacks. Hybrid intrusion detection is defined by both the method used to detect attacks and the placement of the system on the network. Intrusion detection system may perform either misuse detection or anomaly detection and may be deployed as network-based or host-based system. This paper proposes to distribute classical intrusion detection model with mobile agents making an agent-based hybrid intrusion detection system. The proposed model can help detect simple intrusions in early stage and also distributed intrusions by monitoring several subjects installed on network. Main benefit from mobile agents in such system is ability to generate separate services for specific tasks and analyze unknown user patterns with several methods of artificial intelligence.
Mostrar más [+] Menos [-]In silico analysis of steady state mechanisms of metabolic networks in COBRA Toolbox and FBA-SimVis
2011
Odzina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Pentjuss, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Metabolic analysis is one of the research focuses of systems biology. Two aspects of metabolic networks -network topology and stoichiometry - are what current researchers are most interested in, and both studies have revealed significant information. The research of the stoichiometric matrix of metabolic network has generated a series of powerful methodologies such as flux balance analysis (FBA). For FBA different methods execution are used different software like COBRA Toolbox and FBA-SimVis. The aim of this paper is to compare and analyze functionality of these two toolboxes, metabolic network data conformation conditions, and to compare all available FBA methods comparison in calculation possibilities and visual interpretation way. FBA, when analyzing all fluxes using different options, gives results in its metabolic network flow chart, although Cobra Toolbox returns the results in the matrix in number formats. FBA-SimVis for Steady state metabolic network models analysis is provided for a small metabolic network, because making some FBA analysis there are a ten possibilities to change an unlimited count of variables, to choose or change or optimize reactions as variables. Cobra Toolbox for Steady state metabolic network models analysis is provided for greater metabolic networks with hundreds or thousands of reactions. It allows changing an unlimited count manipulating and optimizing reactions fluxes.
Mostrar más [+] Menos [-]Characterization of severe damages of spruce (Picea abies (L.) H. Karst.) stands in relation to soil properties
2011
Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Miezite, O., Latvia Univ. of Agriculture, Jelgava (Latvia) | Bardule, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Severe damages of spruce stands were found during recent years in several countries of the Baltic sea region. Characteristic indications of these damages are trees with brownish drying tops distributed across the whole compartment. During the first year only forests on drained organic soils suffer. In the second and third years, according to experiences gained in Lithuania, the damages move to other stand types. In Latvia, the first signals about the damages of spruce stands arrived from the company ''Rīgas meži'' in May, 2010. ''Rīgas meži'' found damaged stands in 2 forestries. The most of the damaged stands were on organic soils. The inspection of other forests by the State forest service identified similar damages in Southern part of Latvia as well as in other regions with considerable areas of organic soils. In August, 2010 ''Rīgas meži'' did their own inspection in Olaine and Tīreļi forestries and found out that 24% of spruce stands has characteristic signs of damages, and in 10% of stands dead or significantly damaged trees were found. Due to theses damages, about 300 ha of spruce stands were harvested in sanitary clear-felling in 2010. Spreading of spruce bud scale, Physokermes piceae (Schrnk.), is found to correlate with damages of spruce stands in Latvia and Lithuania. This pest is well known in both countries, but never before it caused any serious damages to spruce stands. In Sweden another bud scale insect (Physokermes inopinatus Danzig and Kozár) is found to be the reason for spruce damages.
Mostrar más [+] Menos [-]The assessment of contribution of forest plant non-wood products in Latvia's national economy
2011
Donis, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Straupe, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
The forests in Latvia occupy 49.9% of territory and they have significant economic, ecologic and social functions. The notion ‘forest value’ is frequently understood as the value of wood only but non-wood values are often neglected because there are methodological and practical difficulties to estimate them in monetary terms. The list of forest plant non-wood product (FPNWP) groups potentially important for Latvia was made and the significance of them in Latvia’s national economy was estimated. To obtain the information about FPNWP in Latvia (kinds, amounts, value, own-consumption) the public opinion poll was carried out. 77% of the residents of Latvia aged 18 - 74 have gathered the nature products in Latvia in 2010. The most significant FPNWP are mushrooms, wild berries of family Ericaceae - Vaccinium myrtillus L., Vaccinium vitis-idaea L., Oxycoccus palustris Pers. and birch sap. The contribution of FPNWP in the Latvia’s national economy in 2010 was 66.8 million LVL, including 8.9 million LVL for the products sold in the market or exchanged among households.
Mostrar más [+] Menos [-]Management competences assessment in small and medium-sized forest enterprises
2011
Tunkele, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Marcins, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Domkins, A., Forest and Wood Products Research and Development Inst., Jelgava (Latvia)
The role of small and medium-sized enterprises (SME) in the development of economics becomes more important, as they can quickly re-orientate in the rapidly changing economic situation, and they are the main guarantee of wellbeing on the regional scale. Although these enterprises are different, still the SME in the European Union meet several similar difficulties. One of the main problems of the SME is lack of management competences that causes difficulties in ensuring efficient management of the enterprises. The aim of the research was to investigate the competences that are necessary for the employees to carry out their duties from the point of view of small and medium-sized forest enterprises (SMFE). The task of the research was to identify problems faced by the SMFE management in daily business. To get results, the qualitative interview method was used as well as, survey was carried out, and the obtained data from well-established methodology and criteria were evaluated. The research results show that the distribution at the SME is specific professional competence with 40%, social competence with 23%, methodical and individual competence with 19% and 18%. The results show that necessary management competences in SME and large enterprises are equal, but the kind of their application and topicality differ; therefore, it is essential to organize activities of professional development concerning the definite model and type of business. The professional teaching models for SMFEs should be according to enterprises management specifics, focusing on the fact that managers of SMFEs to combine the competences.
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