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Changes of jelly structural properties depending on different sweet matters
2011
Kronberga, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
There is growing interest in products without added sugar; thus, sugar consumption is directly related to diabetes and other illnesses such as obesity. A change in the type of sugar and content may therefore both change the perception of sweetness and texture of products. The aim of the research work was to evaluate properties of agar-agar jellies prepared with inulin syrup, galactose syrup and malt extract to replace sugar. Agar gels were prepared to substitute sugar with inulin syrup, galactose syrup and malt extract. Texture of experimental samples was determined by using a Texture Analyser (Model TA.XT Plus; Stable Micro Systems). Colour of jellies was evaluated by using Colour Tec-PCM and Jenway 3510 was used for pH measurements. Obtained results showed that different kinds of sugar containing syrups could be used as sugar substitute for production of a new type jellies. Hardness of the experimental samples is influenced by the sugar type containing syrup. The hardness is determined in the experimental samples by replacement of sugar by increasing concentration of inulin syrup. Decreasing hardness values are observed by increase of added malt extract (maltose) and galactose syrup concentration in samples. The pH values of experimental samples ranged between 3.11 and 4.45. Higher L* value of experimental samples are with galactose syrup. Lightness “L” changed between 20.92 and 18.11 increasing inulin syrup concentration. The same situation can be observed using malt extract as sugar substitute.
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 [-]Efficacy of the first large-scale rabies oral vaccination campaigns in Latvia
2011
Olsevskis, E., Latvia Univ. of Agriculture, Jelgava (Latvia);Food and Veterinary Service, Riga (Latvia);Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia) | Liepins, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lamberga, K., Food and Veterinary Service, Riga (Latvia) | Rodze, I., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia)
Rabies is present in the entire territory of Latvia and as a zoonosis poses risk to both human and animal health. The disease is also endemic in countries bordering with Latvia, namely Lithuania, Estonia, Russia and Belarus. Reservoirs for the rabies virus (RABV), the causative agent of the disease in Latvia, are the red fox (Vulpes vulpes) and the raccoon dog (Nyctereutes procyonoides). The first large-scale oral rabies vaccination campaigns using aircrafts were carried out in spring and autumn 2005 using Fuchsoral® SAD B19 oral vaccine baits. In total, 1,894 wild animals (1,366 foxes and 528 raccoon dogs) were hunted in vaccinated areas to evaluate the efficacy of the campaign. After spring and autumn vaccination campaigns, 51.6% of the fox and raccoon dogs were positive for tetracycline. Herd immunity was found in 50.5% of foxes and raccoon dogs using FAVN test and only in 14.8% using ELISA test. After oral vaccination campaigns, rabies incidence decreased in vaccinated area, however, an increase of the incidence was observed in unvaccinated area. Despite the slight increase in rabies incidence in Latvia in 2006 compared to 2005, in 2005 only 141 rabies cases (30%) were found in the vaccinated area whereas 330 cases were detected in the unvaccinated area.
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 [-]The use of black-box modelling in bioprocess scale-up
2011
Mednis, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
Computer models of bioprocesses have become an essential tool in biotechnology. This paper describes various bioprocess scaleup releated problems. The problems at different scales are explained. In this paper the use of computer model in E.coli fermentation scale-up from shake flask to laboratory scale bioreactor is discussed. A black box modelling approach was used. Fermentation results have been visualized and discussed. The computer model created in Matlab environment was used for bioprocess behaviour prediction. Possible bioprocess scale-up software improvements and bioprocess optimization are discussed.
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 [-]Low-cost electrical energy monitoring method with wireless ICT
2011
Apse-Apsitis, P., Riga Technical Univ. (Latvia) | Avotins, A., Riga Technical Univ. (Latvia | Ribickis, L., Riga Technical Univ. (Latvia
The electricity consuming end-user profile has changed in latest years, due to development of new electrical devices with increased functionality and complexity. Also increasing number of electricity consuming equipment that is available to end-user, makes very hard to identify real electricity consumption of each device. The existing wall plug digital power meters are too expensive for long-term power metering of each consuming device. The article describes a different approach of power metering system that lowers the costs and price of needed metering equipment. A new concept of low-cost energy monitoring system with wireless communication is developed.
Mostrar más [+] Menos [-]Determination of organizational sustainability in rural areas
2011
Navickas, K., Siauliai University (Lithuania) | Navickiene, R., Siauliai University (Lithuania)
The article analyses organizational internal and external environments, their possible correlations with 4 components of sustainability, and the principal determination models for sustainability of organizations. Based on the general principles of sustainable development organizations, a model for the determination of organizational sustainability has been developed. The use of self-organizing neural networks allows the identification of the external sustainability of each forest enterprise and the endeavour to explore vital, social, anthropogenic and economical efficiency. The determination of the forest enterprise external sustainability is expected to help better manage the external sustainability of forest enterprises and explain the reasons for a respective level of external sustainability.
Mostrar más [+] Menos [-]Radial growth of Norway spruce in the polluted western part of Latvia
2011
Zalkalns, O., Latvia Univ. of Agriculture, Jelgava (Latvia)
Environmental pollution that has been one of the key issues for decades has still not lost any of its topicality. In order to study the impact of air pollution on the growth of Norway’s spruce (Picea abies (L.) Karst.), 31 sample plots were established at different distances and directions from the pollution points in the Western part of Latvia. The plots were established starting from the year 2008 summer-autumn season and finishing with the spring of 2009. The selected stands were 32 - 171 year old and of different forest site types. The selection was used in the State Forest Service database and cartographic materials. Empirical data was obtained from each of the plots which reflected the environmental effects on the trees. To ascertain the effect of air pollution on the growth of Norway spruce, the algorithm based on additional increment to volume was used. Air pollution affects eating, regardless of age and the type of growing conditions. Pollution effects are closely related to the distance from the source.
Mostrar más [+] Menos [-]Influence of genetic factors on Norway spruce (Picea abies (L.) Karst.) above-ground biomass and its distribution
2011
Libiete-Zalite, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
It is essential to have information on the tree biomass due to the fact that it is an important ecosystem pool for reporting changes in carbon stocks of forests and increased attempts to diversify the energy sources. In Latvia, comparatively few studies have focused on this topic so far. Our study was conducted on two 36 - 38 years old Norway spruce plantations. Detailed stem analysis of 39 trees was performed, and biomass of the above-ground tree components was determined. We analyzed tree and clone-level biomass distribution, biomass relations with tree dimensions and dependence on the genetic factors. The mean total biomass (kg d.w.) of all analyzed sample trees was 131.4 ± 10.58 kg, the mean biomass of stem 85.9 ± 6.98 kg, the mean biomass of dead branches 8.3 ± 0.82 kg, the mean biomass of living branches 23.5 ± 2.34 kg and the mean biomass of needles 13.7 ± 1.22 kg. On average, 66.1% of biomass was allocated to the stem, 6.4% to the dead branches, 17.4% to the living branches and 10.1% to the needles. The biomass of the analyzed trees positively correlated with all tested tree parameters - DBH, tree height, stem volume. Typically, with increasing tree parameters total biomass and stem biomass increased rapidly but branch and needle biomass increased slowly. Significant differences of tree dimensions were detected between the clones, and the differences in total biomass and stem biomass were clearly correlated with the differences in tree dimensions over clones. No significant impact of the clone was found specifically on the tree biomass or its distribution.
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