2018, Vol. 16, No. 4

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/5377

Sirvi

Nüüd näidatakse 1 - 20 33

Extended use of Sphagnum peat as a biosorbent for Zn(II): repetiti ous sorption-desorption process
(2018) Denisova, V.; Tihomirova, K.; Mezule, L.
In this study, continuous biosorption - desorption cycles in a fixed - bed column were performed to evaluate the extended use of sphagnum peat as biosorbent material to remove Zn(II) ions from aqueous solutions. Biosorption - desorption studies revealed that the sphagnum peat as biosorbent could be regenerated using 0.1M HCl as eluting agent with more than 70% recovery in four successive biosorption - desorption cycles. The results showed that the sphagnum peat should be used as an alternative, effective and low - cost biosorbent for Zn(II) ions removal from polluted aqueous solution.
Application of conversion model for designing hydrodynamic pumps in turbine mode
(2018) Polák, M.
The use of the smallest water resources has been coming again to the centre of interest in recent years. A water engine – turbine, is the heart of these power plants. This is usually the highest expense for the investor, in terms of cost. The effort is therefore to seek investment less demanding alternatives. One of them is the use of hydrodynamic pumps in reverse turbine operation. This paper provides a methodology for conversion of parameters of the smallest power pumps (micro hydro sites) to turbine operation. The conversion model is based on the results of experimental research at the author's workplace and is suitable for pumps with low specific speeds and outputs. The pump design process for turbine mode is complemented by a practical example for a specific deployment site. This example also serves to verify the accuracy of the conversion model.
Effect of drying technologies on bioactive compounds maintenance in pumpkin by-products
(2018) Kļava, D.; Kampuse, S.; Tomsone, L.; Kince, T.; Ozola, L.
During the pumpkin processing large amounts of waste material as a combination of pumpkin peel, seeds and the flesh between seeds has produced. Therefore it is important to investigate the possibilities for using the pumpkin residues. The aim of this resea rch was to investigate the effect of different drying technologies on maintenance of bioactive compounds in pumpkin by - products. Two pumpkin residue products of Hubard group pumpkins were used to obtain pumpkin powder: residue products formed in the proces s of extracting industrial pumpkin purée by heating it in a heat exchanger and treating through a sieve of pulpier; residues resulting from pumpkin juice extraction process mechanically pressed from fresh, chopped pumpkins. In order to be able to choose th e most suitable drying technology pumpkin by - products were dried in the microwave - vacuum, convective (at 40, 50, 70 and 80 °C ) and freeze - drying type dryers. For all samples total carotenes, the ascorbic acid, total phenols content (TPC) and antiradical ac tivity (DPPH ̇, ABTS ̇+ ) were determined by using standard methods. The highest total carotenes content was retained in freeze - dried pumpkin powders. The most suitable drying method for obtaining pumpkin powder with the highest ascorbic acid, total phenolic content and antiradical activity is drying in convective type drying at 80 °C temperature.
Efficiency of the use of field beans in fattening lambs
(2018) Kairisa, D.; Aplocina, E.
The breeding and feeding of self produced pulses to livestock is one of the important directions of research for reducing the production costs of livestock products. Experiment on the effective using of the field beans to lambs for fattening was arranged in three replications using the Latvian Da rk - headed breed male lambs. The mixture of concentrated feed consisted of 50% of bean and 50% of oat. Lambs were weighed at the starting and ending of the trial. Carcass quality was assessed according to the European standard for the classification of carc asses of sheep. The fattening period lasted from 37 to 94 days, on average 63 ± 3.6 days. The average live weight gain per day was 247.4 ± 13.85 g, and live weight increased on average by 15.3 ± 0.94 kg. Significantly higher ( P < 0.05) growth rate during fattening period reached lambs of 3rd group, where lambs started fattening above 27 kg of live weight, reaching a 276.8 ± 26.26 g daily live weight gain. The quality of the obtained carcasses was an average, and score for musculatu re was from R to O class, but the average score for fat deposition was from 3 to 4 points. The mixture of field beans and oats provided 19.3% of crude protein and 12.1 MJ of metabolizable energy per 1kg of dry matter, and its unlimited feeding provided med ium lamb's growth rate. The level of feed conversion was 7.56 kg of dry matter .
Evaluation of greenhouse gas emissions and area of organic soils in cropland and grassland in Latvia – integrated National forest inventory data and soil maps approach
(2018) Petaja, G.; Okmanis, M.; Polmanis, K.; Stola, J.; Spalva, G.; Jansons, J.
The aim of the research was to assess distribution of organic soils in farmlands for the time period between 1990 and 2015, as well as to carry out a recalculation of GHG emissions from organic soils in grassland and cropland. We evaluated the area of typical organic soils using digitized soil maps created between 1960s and 1980s there were 183,000 ha of cropland and grassland on organic soils. A selected number of areas on organic soils intersecting with the National forest inventory (NFI) plots were surveyed. We found that 66 ± 10% of surveyed plots still conforms to criteria for organic soils according to Intergovernmental Panel on Climate Change (IPCC) guidelines; in the rest of plots soil organic matter has been mineralized and these areas do not conform to IPCC criteria of organic soils. The following distributionof organic soils was estimated in cropland – 6.3 ± 3.3% in 1990 and 4.1 ± 3.4% in 2015, but in grassland – 11.6 ± 3.6% in 1990 and 7.7 ± 3.9% in 2015. The annual reduction of GHG emissions due to reduction of area of organic soils in cropland in 2015 corresponds to 1,400,000 tonnes CO2 eq. in comparison to 1990 and in grassland – to 1,100,000 tonnes CO2 eq. The estimated reduction of the GHG emissions due to conversion of organic soils into mineral soils, comparing the average value in 2005–2009 with the projection for 2021–2030 on average will correspond to 313,000 tonnes CO2 eq. annually, however LULUCF sector still won’t become a net CO2 sink according to the GHG inventory data on other land use categories and carbon pools.
Concentration of air-borne microorganisms in sport facilities
(2018) Kic, P.; Ruzek, L.; Popelarova, E.
This paper is focused on the microclimatic research in several buildings and ro oms used for sport at the University. The attention is paid mainly to the problems of dimensions of space, capacity and activity of sportsmen, and influence of space ventilation. The air samples for microbiological analyses were taken by the microbial air sampler Merck Mas - 100 Eco and cultivated by potato - dextrose agar and nutrient agar. Captured microorganisms, are expressed as colony forming units per m 3 (CFU m - 3 ). Measurement results showed that bacteria average quantity was statistically significantly less without students (562 CFU m - 3 ) than with students (1,024 CFU m - 3 ). The students inside the rooms increased the bacteria concentration. From this point of view th e ventilation is not adequate for the removal of bacteria from ventilated spaces. From the results we can conclude that the great importance on the air quality in terms of a specific bacteria concentration has the specific volume of the room per one athlet e. The worst situation is in rooms with the smallest volume, which has the largest biological load of the space. The lowest quantity of bacteria was in the swimming pool all year round (152 to 300 CFU m - 3 ). The opposite situation was in average quantity of filamentous fungi, which was with students and ventilation (57 CFU m - 3 ) and without students but without ventilation (109 CFU m - 3 ). The pollution of air by fungi was higher without ventilation.
Modelling of operator’s focusing scheme along working hours: Windrowing and cultivating operations
(2018) Szabó, I.; Hushki, M.; Bártfai, Z.; Lágymányosi, A.; Kátai, L.
Enhancing productivity and cost reduction are two main targets for any production operation. In the agricultural field; It is the role of researchers to come out with reliable models and make it available to be used in m odern farming management organizations as well as to the rural farmers. When it comes to the Human Machine Interface it is essential to assess the system in term of the Human Cantered Design aspects. This research is focusing on the developing simple model s for the operator’s focusing scheme as a human behaviour inside an off - road vehicle cabin based on the operator’s focusing scheme measuring along working hours using proven and up to date technologies. The results of this research provide the decision mak ers with reliable inputs using proven methodology regarding the change of operator’s focusing scheme along working hours in two agricultural operations “windrowing and cultivating”. Both operations are requiring continuous physical involvement of the opera tor for checking the attached tool and steering of the vehicle in the planned track, which is directly related to the accumulated passive fatigue as a main contributor of resulted data.
Mathematical description of loading curves and deformation energy of bulk oil palm kernels
(2018) Kabutey, A.; Herak, D.; Mizera, C.; Hrabe, P.
The study aimed at describing the experimental and theoretical relationships between t he force and deformation curves as well as the deformation energy of bulk oil palm kernels under compression loading. V essel diameters of 60, 80 and 100 mm with initial pressing heights of the bulk kernels measured at 40, 60 and 80 mm were examined by appl ying a maximum compressive force of 200 kN and a speed of 5 mm min - 1 . For the theoretical description of the force and deformation curves, the tangent curve mathematical model was applied using the MathCAD 14 software where the force coefficient of mechani cal behaviour, A (kN), the deformation coefficient of mechanical behaviour, B (mm - 1 ) and the fitting curve function exponent, n ( - ) were determined respectively. The determined coefficients in addition to the maximum deformation values obtained from the co mpression test were used for the estimation of the theoretical or analytical deformation energy. The determined regression models expressing the deformation, numerical energy and theoretical energy as well as the tangent model coefficients A and B dependen t on the vessel diameter and pressing height were statistically significant ( P < 0.05) or ( F - ratio > F - critical) . Improving the mechanical pressing of oil extraction for both domestic and industrial applications still remain a concer n of researchers and en gineers.
Optimization of arable land use to guarantee food security in Estonia
(2018) Põldaru, Reet; Viira, Ants-Hannes; Roots, Jüri; Estonian University of Life Sciences. Institute of Economics and Social Sciences. Department of Business Informatics and Econometrics
Agricultural and food sector has an important role to play in ensuring food security. A competitive agricultural sector warrants fo od security through increasing level of self - sufficiency in food, and export of surplus production in the sub - branches where it has a comparative advantage. One of the strategic tasks of the state is to secure food supply for the population. To perform thi s task, the state should estimate if the agricultural producers have the necessary capacity and resources to produce food to meet the needs of population. Mathematical modelling can be used as a tool in solving this analytical problem. The paper demonstrat es possibilities of implementing linear programming model in optimizing the use of arable land for ensuring the food demand of Estonian population. The Estonian arable land use optimization model is essentially a static balancing model that simulates the d emand and supply of basic food products (meat, dairy products, cereal products and potatoes). The basis for the demand side in the model is Estonian population, divided into 10 groups according to gender and age. The energy and protein needs of the respect ive population groups are taken into account. The supply side of the model is a typical agricultural production model that guarantees the consistency of crop and livestock farming. The model consists of 163 variables and 178 constraints (equations). The ob jective of the model is to minimize the use of arable land for field crops to ensure fodder for animal feed, and food for human food consumption. The model is used to analyse various land use strategies. According to the modelling results for ensuring food security of Estonia and to maintain export of dairy products, for which Estonia has a comparative advantage, in the 2016 volume, the total optimal arable land equals to 490,688 ha . There should be 83,600 dairy cows (with average milk yield 9,000 kg cow - 1 ) . It is necessary to grow 755,700 piglets per year in order to secure 40 kg of pork per inhabitant. Land use optimization results indicate that Estonian agriculture is able to supply Estonian people with the minimum necessary main food products to guarante e food security, and allows to export essential products (cheese, butter, skimmed milk powder, whole milk powder).
Assessment of the actual hand position on the steering wheel for drivers of passenger cars while driving
(2018) Hruška, M.
This work deals with the assessment of the actual position of the hands on the steering wheel of drivers of passenger cars in specific driving modes. The findings are compared with the location that is generally considered to be optimal in terms of both active and passive safety, and the long - term effects on the health of the driver. The research desc ribed in this work was carried out on a sample of randomly selected drivers in the Czech Republic. For all of the measurements, one identical neutral passenger middle - class vehicle, with which none of the test subjects had previous experience, was selected . The reason for this research was to model a normal situation where the driver controls a vehicle with his hands on the steering wheel in a position that is only the result of his or her own intuition and the subjective sense of the driver’s comfort. On t he basis, of a statistical evaluation of the obtained data, it was found that the introductory hypothesis, which states that a significant part of the tested sample of drivers holds the steering wheel in an unsuitable manner, can be confirmed. This fact ne gatively impacts not only on the reduction of active and passive safety, but also affects the health of drivers who drive a large amount of kilometres annually. The results of this work can be used in the design of cabs and modern passenger car systems tha t will be able to motivate the driver to hold the steering wheel in an optimal way. This will directly affect road safety and positively influence the health of drivers.
Morphological and biochemical indicators of Fusarium oxysporum f sp. fragariae in strawberry crops (Fragaria x ananassa Duch) in the province of Pichincha, Ecuador
(2018) Salazar, S.; Bayas-Morejón, F.; Niño, Z.; Guevara, J.; Ruilova, M.; Merino, O.; Donato, W.; Guamán, J.
Fusarium oxysporum f. sp. fragariae is a fungal pathogen, transmitted by soil in crops of strawberry (Fragaria x ananassa Duch.), which causes wilt disease that, kill the strawberry cultivars. The disease caused by Fusarium oxysporum f. sp., fragariae is hard to detect as the of the symptoms are similar with other soil-borne diseases. In spite of detection methods targeted F. oxysporum using molecular criteria have been developed, they have not been shown to successfully identity the unique identity of F. oxysporum strain that causes this disease. In Ecuador, the cultivation of strawberry has acquired great importance for the consumption, promoting the increase of its production. However, the process of importing plant material from producing countries for the purpose of improving production has contributed to the spread of the fungus. The objective of this study was to identify the presence of the Fusarium oxysporum f. sp fragariae by means of morphometric identification and the application of biochemical methods (BIOLOG) in the province of Pichincha. Fifty-two diseased strawberry plants and 52 asymptomatic plants were analyzed. Of these, 13 isolates were identified by morphometry as F. oxysporum. However, through BIOLOG four strains were identified as F. oxysporum, 5 as Fusarium sp., 2 F. lateritium, 1 F. udum and 1 strain as F. sacchari. The results obtained through the identification and evaluation confirmed the presence of F. oxysporum f. sp., fragariae in evaluated strawberry cultivars, thus determining the high risk to exist if the pathogen spreads in new plantations in Ecuador.
Effect of environmental temperature on bending strength of the finger jointed aspen lumber
(2018) Iejavs, J.; Spulle, U.; Jakovlevs, V.; Buksans, E.; Zelmenis, A.
Glued sauna wall boards are used as non-load-bearing structures. These products are subject to aggressive microclimate impact and very often for the gluing in length and width thermoplastic polyvinyl acetate adhesives (PVAC) are used. In the performed research sauna wall boards made of common aspen (Populus tremula L.) with mean wood moisture content 8% were used. For the gluing in length with finger joint PVAC glue of D4 (LVS EN 204) group was used. The aim of the research is identifying the impact of the environmental temperature on the strength of finger jointed aspen timber in 4 point static bending (in compliance with standard LVS EN 408). As a result of the study it was established, that after holding the finger jointed testing pieces visible in flat wise for 3 hours at the temperature of 100°C , the mean bending strength decreased by 56% or 31.7 MPa in comparison to that held in the standard atmosphere. In case of the aspen timber with finger joints visible in edge wise held for 3 hours at the temperature of 100°C , the bending strength decreased by 60% or 29.3 MPa in comparison to the testing pieces of the same type held in the standard atmosphere.
The impact of weather conditions on microclimate in storage facilities
(2018) Bradna, J.; Šimon, J.; Hájek, D.; Vejchar, D.
The key to maintaining good qualitative parameters of stored grain on farms is to achieve and maintain suitable storage temperatures relative to the outside temperature. In the framework of this research, the main focus was on typical representatives of grain storage facilities used in the Czech agriculture. In the post - harvest period after the crops were stored in the chosen storage facilities, the temperature of the material was monitored at 15 - minute intervals using an external temperature probe as well as the temperature and dew point of the outdoor air. A simple linear regression model was used for data analysis. The correlated temperature d ependence of the stored grain varies considerably in the monitored storage facilities. The storage halls were characterized by a low dependence (r = 0.2208) of the temperature of the material on the outside air temperature in the first 4 months following t he harvest when the grains were being stabilized by active aeration. In addition to the grain and the air temperature, the second focus was monitoring the dew point, i.e. assessing the risk of water vapour condensation on the surface in the upper layer of the stored grain, which is very undesirable for maintaining the quality of the stored grain. The results show that the monitored storage hall can be characterized by the ability to maintain the required climate due to outdoor climatic conditions. In genera l, this ability mainly depends on the type and design of the storage facility, the aeration system and also the storage capacity. Mainly during spring the dew point and water vapour condensation can often happen within the grain, therefore the need to focu s on appropriate measures such as reduced aeration or increased grain mixing, and thus avoiding the formation of critical spots.
The impact of the termination technology of agro-ecological service crops on soil properties in open field vegetable production
(2018) Tamm, Kalvi; Bender, Ingrid; Nugis, Edvin; Edesi, Liina; Võsa, Taavi
The agro - ecological service crops (ASC) are introduced in the agro - ecosystems to provide or enhance ecological services, thus promoting the whole soil - plant system equilibrium. To avoid competition with the subsequent cash crops, the growth of the interposed ASC is terminated in advance of the cash crop planting. The traditional, most widespread technique to terminate the ASC is incorporation as green manure into the soil by tillage (GM). However, since tillage includes energy and labour consuming and soil dis turbing operations, the use of no/reduced tillage techniques (as the roller crimping technology - RC) has received increasing interest. An international research consortium (SOILVEG) including Estonian Crop Research Institute, was established in 2015 with th e aim to study among others the impact of ASC termination on soil dry bulk density (BD), water content, soil structure and microbiological activity. Data are collected from Estonian tri als in 2016 and 2017 at Jõgeva. The physical properties of 0 – 40 cm soil layers were determined. Higher BD in soil layers (0 – 20 cm) of plots with ASC and RC was determined comparing to the GM and control plots. Bigger water content in same layer of plots with ASC and the RC was determined comparing to the GM plots. The use of the ASC - s helped to arise ratio of agronomically preferred soil particles. Microbial activity was estimated by assessing of enzyme dehydrogenase activity in 0 – 20 cm soil layer. There were no statistically relevant differences in soil dehydrogenase activit y (DHA) be tween the RC and GM treatments.
Effect of PTO-driven tillage machines on soil particles transfer
(2018) Buřič, M.; Novák, P.; Hůla, J.
Displacement of soil particles by erosion can be seen as a major threat to the quali ty of agricultural land in the conditions of Czech Republic. While the effects of water and wind erosion have long been investigated and reported, the effect of soil tillage technology on soil particles translocation are relatively new area of agriculture research. Soil tillage may contribute to the undesirable translocation of soil particles towards lower - lying parts of fields especially on slopes. The effect of soil tillage implements on soil particle translocation has not been sufficiently explained yet. The object of this research was to assess the influence of PTO (power takeoff) - driven tillage machines on soil particle translocation during secondary tillage (soil preparation). Measurements to determine the displacement of soil particles were performed in location Nesperská Lhota in the Central Bohemia Region. Measurements were performed on a sandy loam cambisol after harvest winter cereals (winter wheat). To indicate displacement of soil particles was used grit of white limestone (size 10 – 16 mm). Limest one was put down into the trench with known position orthogonal to the direction of working operations. Subsequently were performed working operations in the specified sequence. Limestone particles were counted and weighed in each section. It was detected by measuring the different nature of displacement for each machine. Statistical significance of differences in the weight of translocated particles was evaluated for different type of machines.
Faults and the physical workload in sawing and packing-related woodworking processes when considering potential ergonomic solutions
(2018) Kalkis, H.; Roja, Z.; Babris, S.
The forest sector is a high - risk economic sector in Latvia, one in which manual work, awkward postures, the tightening up of individual muscle groups, and work monotony still exists. The aim of this study was to analyse the physical workload and fault modes, and their effects on the sawing and packing proce sses in woodworking when considering potential ergonomic solutions. Results show that packing operators and saw operators alike are exposed to severe loads, and these results coincide with survey results in which employees in these professions complain abo ut the physical load and mention lower back pain. Fault modes and their effects on the sawing and packing processes were analysed using Failure Mode and Effects Analysis, and the main errors which were revealed in packing operations were related to machine ry and lifting equipment, as well as to ergonomics and errors involving the human factor. The risk priority was calculated in terms of a figure. Financial indices were compared before and after any potential improvement in the sawing and packing processes. Analysis proves that investments in the improvement of ergonomics in relation to the automation of the production process saves human resources and is economically favourable when it comes to ensuring the sustainable development of the business in questio n.
Field trajectories proposals as a tool for increasing work efficiency and sustainable land management
(2018) Kroulik, M.; Hula, J.; Brant, V.
Together with the requirement for higher productivity the average performance and the weight of agricultural machines are increasing. Agricultural land is increasingly exposed to pressures caused by agricultural machinery. The heavy agricultural machinery passes across a field are frequently associated with technogenic soil compaction. Soil compaction is one of the main problems of modern agriculture. From the previous measuring of the traffic intensity it was found 86.13 % of the total field area was run - o ver with a machine at least once a year, when using conventional tillage and 63.75 % of the total field area was run - over when using direct seeding technology, with dependence on the working width of the machines. Field passes are inevitable in present agri culture. As a result of the increase of total machines weight, it is necessary to optimize the traffic lines trajectories and limit the entries of the machines in the field. At present, the choice of traffic lines direction is based primarily on the experi ence of drivers or the practice of farmers. There are a number of influences that affect the machine work efficiency. Monitoring of the tractor, on an irregular 8 fields showed the following results. Eight - meter working width tiller or seeder brought short ening of total length of turns at headlands with the change in trajectory azimuth. For purposes of measuring the monitored tractors were equipped with monitoring units ITineris. An overview of the chosen directions of the trajectories and the lengths of wo rking and non - working passes was obtained. Based on the shape of the plot, the trajectory of the lines was also modelled. Suitable traffic lines directions in terms of the ratio of work and non - work passes were searched. Based on records of real trajectori es, the ratio of working and non - working path ranged between 6.3 and 15.2%. It was obvious from the results that the shortening of non - working passes and turns in comparison with the originally chosen trajectory directions was achieved by optimization. Thi s was especially valid for complex shapes of fields. Trajectory optimization leads to a reduction of total le n g th of path in all cases. The reduction in total length of path ranged from 69.7 m to 1 , 004.8 m. Changing the length of the working path ranged fr om 10.9 m to 264.9 m with the change in azimuth. The extension was observed in three cases. The highest part on the change of the overall length of the path presented nonworking rides.
Farm manure amount calculation using statistical data in Latvia
(2018) Priekulis, J.; Aboltins, A.; Laurs, A.; Melece, L.
To calculate ammonia emissions caused by production, storage and application of farm manure, it is necessary to know the amount of farm manure obtained in the country and also the kinds of manure. For this purpose, methodology and computer software are dev eloped to calculate the amount of farm manure based on the data of the Central Statistical Bureau, the technology of farm animal handling in the country and the respective valid normative documents. Upon calculating the amount of farm manure produced in La tvia in 2016, it was stated that approximately a half of the manure is litter manure, one third – liquid manure, and one fifth – manure left in the pastures. The most of manure in Latvia (69% of the total amount) is obtained from milk cows, their calves an d young stock.
Assessment of Calotropis natural dye extracts on the efficiency of dye-sensitized solar cells
(2018) Alami, A.H.; Aokal, K.; Zhang, D.; Tawalbeh, M.; Alhammadi, A.; Taieb, A.
This work presents the construction and testing of solar cells sensitized with natural dyes extracted from plants indigenous to the desert. Calotropis plants are self - sufficient as they grow in very harsh environments, and yet are not consumed by humans or livestock due to their irritating agents to the skin and eyes. The energy generators of these plants are the leaves, which are crushed and processed to produce the dye solution. Also, the Calotropis leaves are covered in a white powder that is thought to aid in mitigating the heat by scattering incident radiation. This powder material is examined and added to the dye as it proved advantageous for the o verall cell efficiency, which reached 0.214% compared with 0.108% for cells with no powder. The produced cells are also compared with ones sensitized by spinach, another common natural sensitizer for dye - sensitized solar cells, and the performance proved t o be significantly better. The fact that Calotropis is a non - food plant is an added advantage to utilizing it as a dye source, along with its intrinsic heat resistance that allows it to survive the harsh desert conditions all year round.
The influence of drying method to the changes of bioactive compounds in lingonberry by-products
(2018) Ozola, L.; Kampuse, S.
The aim of this research was to evaluate the effect of different drying methods on industrially obtained lingonberry pulp juice by - products. For investigations, by - product was dried using hot air dryer (at temperatures 80 °C , 60 °C and 40 °C ), microwave - vacuum dryer and freeze - dryer. The freshly defrosted by - product was used as control. All samples were analysed on the basis of their moisture content, colourimetric attributes (CIE L*a*b* colour system), content of vitamin C (iodometric method), content of total carotenes (TC), total phenol content (TPC), total anthocyanin content (TA) and antiradical activity (DPPH, ABTS + ). The obtained data on content of vitamin C showed a 10% decrease between control and sample dried in hot air at 80 °C . Similar changes were noticed with total anthocyanin content, the lowest amount was also foun in this sample ( 306.72 ± 18.32 mg 100 g - 1 DW). Total carotenes content was higher in freeze - dried sample (5.61 ± 0.16 mg 100 g - 1 DW) which was very close to control sample. A significant loss of total phenol content was noticed after drying, up to 80%, similar ten dencies were noticed with changes of antiradical activity. After evaluating the obtained data, the use of hot air dryer at 80 °C temperature resulted in the lowest amount of vitamin C and anthocyanins in lingonberry by - products, which makes this method unsuitable for drying by - products of these berries. However, vacuum assisted microwave drying and freeze drying showed less damaging impact on dried material.

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