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Quality changes during summer–autumn long-term storage of Scots pine (Pinus sylvestris L.) roundwood
2016
Magaznieks, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Millers, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gzibovska, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
Latvia at the moment does not have precise data about long-term storage of Scots pine. Long-term storage in warm season may lead to significant damages for high priced timber, income reduction for timber sellers and quality loss risk for timber buyers, therefore, roundwood is transported as soon as possible, because of the risk of blue stain, crooks and insect damages. Results of this study on Scots pine were obtained during summer–autumn season of year 2015. Scots pine timber quality changes in long-term storage were analysed in 4 sample stacks – set up in summer (25 July) and stored for 100 days. In every sample plot there was a control pile, a pile with harvester spike damages, a pile with bark damages and a pile with harvester spike and bark damages. There were 32 timber assortments in every pile in order to determine also the emplacement effect in stack. In this study a high correlation was found between pine timber quality changes and meteorological conditions, side surface damages and storage length. By analysing the proportion of blue stain in cross-section and its changes during storage between control assortments and assortments with bark and harvester damages, significant differences were observed, therefore it can be concluded that not only bark damages influence the proportion of blue stain, but also harvester spike rollers. Based on the results of this study, we can predict maximum storage duration during summer–autumn period in Latvia, and it is set from 9 – 16 days.
Mostrar más [+] Menos [-]Testing the 'Rotstop' biological preparation for controlling Heterobasidion root rot in Latvia
2014
Brauners, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Bruna, L., Forest Sector Competence Centre, SIA, Riga (Latvia) - MNKC | Gaitnieks, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
In Latvia, Picea abies and Pinus sylvestris as the commercially most valuable species make more than half of all woodlands. It has been found that about 23% of spruce stands are infected by root rot, caused predominantly by fungal pathogen Heterobasidion annosum s.l. To restrict the spread of root rot in coniferous forests of Latvia, the Joint Stock Company ''Latvijas valsts meži'' collaborated with Latvian State Forest Research Institute ''Silava'' in 2006 and launched a project for testing the Rotstop biological preparation, containing a suspension of Phlebiopsis gigantea spores. This project had a general task to accomplish Rotstop using technology approbation in Latvia and develop control system. Starting with the year 2008, preparation was used for stump treatment during thinning operations. When analysing the field data, a conclusion made in other studies was confirmed - P. gigantea colonizes pinewood more intensively even in case of improper stump treatment. It implies that the quality of stump treatment is decisive when using Rotstop for rot control in spruce stands.
Mostrar más [+] Menos [-]Quality control management problems of wooden product surfaces
2012
Stekelis, K., Latvia Univ. of Agriculture, Jelgava (Latvia)
The added value of woodworks is determined by the surface quality because it is the first one seen and evaluated by the client. In the production process it is quite problematic to evaluate woodworks surface quality because of large production capacity, and the processed material can be instrumentally tested with a definite time shift. In production most frequently the surface quality is evaluated visually, which is not quite precise. At the same time during the mechanical processing of wood noise is caused by cutting tools as they gradually wear out. The same reasons influence the increase of noise and the quality of woodwork surface. The essence of the problem is to analyze the registered increase of the noise level at a definite workplace and simultaneously follow the surface quality of the processed material – roughness and wear-out of the cutting instrument. The objective of the paper is to research the method of the noise level data collecting and application in order to evaluate wooden product surface quality during wood processing by milling machines. It would provide an opportunity to update the management processes of massive woodworks, supervise the surface quality of woodworks, reduce costs and increase the added value.
Mostrar más [+] Menos [-]Quality changes during summer – autumn long term storage of birch (Betula pendula) roundwood
2017
Magaznieks, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Millers, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gžibovska, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The homogeneous and light wood of birch is suitable for different types of treatment processes and is highly valued for products where visual aspect is important, however, birch assortments are highly susceptible to damages caused by fungi during the storage. Such fungal damages cause discoloration of birch roundwood intended for further woodworking. Sapwood discoloration development and its influencing factors for birch roundwood were analyzed in the summer - autumn period of the year 2016 (August, September and October). Control cut for assessment of sapwood discoloration development was made in four birch roundwood stacks in the districts of Auce and Daugavpils. In order to evaluate the influence of harvesting type, side surface damages, placement in pile, storage duration, diameter, distance from the end plane, daily average temperatures, precipitation amount and relative humidity on development of sapwood discoloration, 616 discs from birch log end planes were prepared. After conducting multiple factor linear regression, it was concluded that a significant development of discoloration and its changes for birch roundwood are promoted by harvesting type, placement in pile, distance from the end plane, daily average temperatures and relative humidity (R2 = 0.450). For birch logs that are prepared by harvester with the daily average air temperature + 6 °C, the first signs of discoloration appear after 17 – 18 days, but on all logs stacked in pile they appear after 68 – 69 days. Whereas, with the daily average temperature of + 18 °C, the first signs of discoloration can occur after only six days, but on all logs stacked in pile they appear after 23 days.
Mostrar más [+] Menos [-]Blue stain development of Scots pine (Pinus sylvestris L.) roundwood and its influencing factors
2017
Millers, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Magaznieks, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gzibovska, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The normal wood colour changes due to the biochemical reactions as well as under the fungal exposure. Some of these fungi during all the exposure time cause only a discoloration (staining fungi); others change not only colour, but also the structure of the wood in its further development (wood destructing fungi). The development of blue stain in sapwood of pine roundwood and its influencing factors were studied in the spring summer period of 2016 (April, May and June) in the districts of Nica, Jelgava and Daugavpils. 650 discs from pine log end planes were prepared in order to evaluate the influence of harvesting type, spreading type of fungi spores, placement in pile, storage duration, diameter, distance from the end plane, daily average temperatures, precipitation amount and relative humidity on blue stain of sapwood and rot development. The most important factors influencing the blue stain development on pine roundwood during the storage are the harvesting type of roundwood, spreading type of fungal spores, placement in pile, storage duration, diameter, and distance from the end plane, daily average temperature and amount of precipitation. By evaluating the daily average temperatures, it was concluded that blue stain of sapwood begins to develop when the average daily temperature reaches +5...+6 °С. But when the average daily temperatures reach +10 °С, depending on the harvesting type (chainsaw or harvester) and spreading type of the fungal spores (via air or bark beetle assistance) the first signs of blue stain may occur from 10 to 42 days of storage.
Mostrar más [+] Menos [-]Lies on labels, or cases of misleading consumers on the example of vegetable oils
2019
Hernik, J., West Pomeranian Univ. of Technology in Szczecin (Poland) | Grinberga-Zalite, G., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
In 2018, the Polish Trade Inspection in the whole country carried out an assessment of unrefined vegetable oils and olive oils of various categories. First of all, the correctness of marking, physicochemical parameters, storage conditions, traceability of products and their dates of minimum durability were assessed. In total 380 batches of products were inspected. Results of the examination show that producers cheat consumers by providing, for example, untrue nutritional values or false information about dietetic or health traits. The purpose of this article is to determine what consumers should know to verify the correctness of information on product labels independently. The theoretical part of the article was based on the EU regulations analysis regarding vegetable oils properties, including the characteristics of olive oil. The empirical part concerned data from Polish Trade Inspection reports, as well as statistical data on production and sale of oil and olive oil from the portal Statista. In this article methods of documentary research and comparative analysis were used. For the main conclusion it can be assumed that products of poor quality or incorrect labeling can be found in each product category; therefore, consumers should pay attention to such elements as information in their native language, a full list of ingredients, or correct indication of nutritional values.
Mostrar más [+] Menos [-]Assessment of food safety risks in catering establishments
2007
Melngaile, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of the research was to assess food safety risks in catering establishments. To analyse food safety risks during production and distribution of ready-to-eat food in catering establishments, internal database of the Food and Veterinary service of the Republic of Latvia was used. Catering establishments, food items, technological processing methods, as well as environmental objects were encoded to perform mathematical analyses of state's monitoring and surveillance data. The probability of the microbiological risk factors coliforms and S.aureus in food and environmental samples as well as the total plate count in ready-to-eat food was assessed to forecast common risks in catering establishments and to set hygiene management priorities in frame of HACCP procedures. For estimation of individual risk factors, results were statistically analysed using SPSS statistical package and a p is less than 0.05 was considered to be statistically significant. The significant differences were established between certain bacteria presence in food and such factors as food group, method of technological processing, and type of catering establishment. The results on bacterial contamination of food correlate with the results on contamination of environmental objects. The research suggests that control of food safety risks that is built on testing of pathogenic bacteria is not effective enough to evaluate actual level of implementation of hygiene measures in catering establishments. Risk assessment during routine monitoring both in state's official control level and catering establishments' self-control level should be concentrated on testing of hygiene indicator microorganisms rather than pathogenic microorganisms to establish and prevent food safety risks.
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 [-]Grades and standards: quality management from cradle to coffin
2005
Pedro Vilaseca
Another important aspect of an effective market is the quality of the goods that are sold. Standards to ensure the quality of goods are thus significant determinants of the effectiveness and productivity of markets. For the purpose of promoting competitive markets as well as protecting consumers from dangerous and unsafe products that may be found in the markets, the state can take a leading role in setting and enforcing quality standards.
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