2020

Selle valdkonna püsiv URIhttp://hdl.handle.net/10492/5955

Sirvi

Nüüd näidatakse 1 - 20 234

Acceptance of low-sugar yoghurt among Latvian teenagers
(2020) Zagorska, J.; Ciprovica, I.; Straumite, E.; Majore, K.
Over a thousand year history, yoghurt has become one of a widely consumed product in the world. Its reputation as a healthy food has been undermined recently by concerns over the high sugar content. The majority of consumers expects and prefers yoghurts to be sweet. However, governments across Europe are calling for significant cuts in the amount of added sugar used in yoghurt production. The aim of the study was to evaluate the acceptance of low-sugar yoghurt produced by different commercial β-galactosidases by teenagers. Standardised milk with fat content 2.0% (SC Tukuma piens) was pasteurized at 95 ± 1 °C 5 min, cooled down till 43 ± 1 °C and fermented with β-galactosidase and starter YC-X11 (Chr. Hansen, Denmark) and fermented till pH 4.50 ± 0.20. Different commercial β-galactosidases: Nola™ Fit 5500, Ha-Lactase 5200 (Chr. Hansen, Denmark), GODO-YNL2 (Danisco, Denmark) and BrennZyme (Brenntag PolskaSp, Poland) were used. Fermented samples were gently mixed and cooled down till 6 ± 1 °C and 5% (w/w) of sugar was added to each sample. Sensory evaluation of the yoghurt’s samples was performed by teenagers (14–18 years, n = 50) at Aizputes Secondary School (Latvia). Lactose and monosaccharides concentration prior to sugar addition was detected by HPLC (Shimadzu LC 20 Prominence, Japan). The lactose hydrolysis into glucose and galactose by the use of β-galactosidase helps to increase sweetness through an occurrence of natural sugars in milk. During sensory evaluation, teenagers admitted the yoghurt with reduced sugar as sweet, significantly sweeter (P < 0.05) was yoghurt sample with Nola™ Fit 5500. The results demonstrated that it is possible to reduce sugar in yoghurt production and to gain consumer acceptance through the occurrence of glucose and galactose, but it is problematic to offer lactose-free or reduced lactose products to consumers without lactose intolerance.
The advanced application of the wood-originated wastewater sludge
(2020) Brovkina, J.; Shulga, G.; Ozolins, J.; Neiberte, B.; Verovkins, A.; Lakevics, V.
The wood hydrothermal treatment is one of the plywood production’s stages, which resulting in the production of wastewater containing such components as hemicelluloses, lignin and wood extractive substances (HLES). It is necessary to improve the wastewater treatment technology with the aim to enhance the yield of sludge from plywood wastewater for its effective and rational recycling. In the present study, the optimal coagulation conditions for the HLES removal have been found using the developed aluminium salt-based coagulant. The developed composite coagulant is characterized by lower doses, a wide range of the work pH values, the insensitivity against temperature changes and a higher coagulation efficacy compared with traditional aluminium salts. The proposed treatment technology generates many tons of woodoriginated sludge – a biomass coagulate. It was found that the formed coagulate produced in the process of wastewater treatment can increase the sorption ability of clay. The optimal content of the dry coagulate in a clay sorbent does not exceed 0.11%. The sorption capacity of the developed sorbent for water, rapeseed and silicone oil increases by 35%, 31% and 21%, respectively, relative to the unmodified clay sorbent. The sorption efficiency of heavy metals from water solutions is also increased by 10–12%. The thermal treatment of the modified clay sorbent at the high temperature leads to an increase in its sorption capacity for oil products.
Advantages of electric resistance method for baking bread and flour confectionery products of functional purpose
(2020) Kulishov, B.; Kulishova, K.; Rudometova, N.; Fedorov, A.; Novoselov, A.
In this paper we studied the effect of the baking method on the preservation of betacarotene in two types of products: pan wheat bread and sponge cake. Five sources of betacarotene were used in the study, three of which are commercially available samples, and the two others are experimental samples of supramolecular complexes of beta-carotene with alpha- and beta-cyclodextrins in powder form (molecular ratio 1: 1). Bread and sponge cake were baked by convective and electric resistance methods. The values of temperature and current flowing through the dough were monitored during electric resistance baking. The beta-carotene content was measured in the dough after kneading, in the cake batter after mixing and in the finished products after baking and cooling. The beta-carotene content was evaluated by spectrophotometry after extraction. The control samples of bread and sponge cake were baked without adding beta-carotene. Different sources of beta-carotene exhibited varying stability in bread and sponge cake. Bread samples baked by the electric resistance method with addition of supramolecular complexes had minimum losses of beta-carotene. Electric resistance baking ensured lower losses of beta-carotene in bread and sponge cake samples.
Aerobic solid-state fermentation of the solid fraction of pig slurry
(2020) Uvarov, R.; Shalavina, E.; Briukhanov, A.; Vasilev, E.
Current expansion in the pig number in Russia and their concentration in separate locations contribute to higher environmental risks. One key risk factor is the slurry produced. To utilize it more efficiently, many pig farms introduce its solid-liquid separation. The study objective was to explore the feasibility of accelerated aerobic solid-state fermentation of the solid fraction of pig slurry in closed installations. The stable thermophilic process under the temperature above +55 °C achieves shorter processing time of 3–4 days. To date, however, there is no representative evidence of such an experience. Four options of fermented mixture composition were tested based on two types of the solid fraction of pig slurry: Type 1 fraction coming from a screw separator and Type 2 fraction coming from a decanter centrifuge. The fermenter operating modes were tested in the authors’ previous studies associated with processing of the solid fraction of cattle manure and bedding poultry manure. The intensity measure of fermentation was the temperature reached by the processed material in the fermenter. Under the investigated operation modes, the stable temperature was observed for nine days in the mesophilic process: 20 °С to 55 °С; in some cases, the transition to the thermophilic process – above 55 °С was recorded. Adding the catalytic components to the processed material accelerated the substrate self-heating and a higher temperature up to 59 °С was reached. This suggests that the considered operating modes of the fermenter were suitable for the fermentation of the specified substrate.
Agroecological prospects of using corn hybrids for biogas production
(2020) Mazur, V.A.; Pantsyreva, H.V.; Mazur, K.V.; Myalkovsky, R.O.; Alekseev, O.O.
Ukraine is an agricultural country with great agricultural potential for biogas production, which is the key to fertile soils and favorable climatic conditions for energy crops, including corn. The article analyzes the experience of using biogas in Ukraine and the world, its mechanism of production. The leader in biogas production in the world is the European Union in general and Germany in particular. The total number of biogas plants in Europe exceeds 11 thousand, of which 7.2 thousand in Germany. Іnstalled biogas, which is released in the process of complex fermentation of organic waste, consists of a mixture of gases: methane – 55–75%, carbon dioxide – 23–33%, hydrogen sulfide – 7%. An important sector of renewable energy sources in biogas production is presented and the prospects for its use are determined. The energy dependence of our country on the volumes of imported natural gas is analyzed. The main aspects of biogas production are explored using renewable energy sources that are inexhaustible in our crane and the phased operation of the biogas plant is investigated. The real advantages of the need for biogas production and use in our country are outlined. Problems aimed at the development of alternative energy have been proved in order to detect environmental pollution. It has been established that in Ukraine the use of corn silage to improve the efficiency of biogas production at existing biogas stations has not been used so far. The problems of increasing the yield of corn plants have been proved not only by breeding and genetic methods, but also by cultivation technology.
Agroecological substantiation of Medicago sativa cultivation technology
(2020) Telekalo, N.; Melnyk, M.
Medicago sativa is one of the most productive legumes, which provides high protein production. Application of the biostimulant and microfertilizers is quite relevant and effective. Theoretically substantiates and presents ways to solve the scientific problem of formation of Medicago sativa productivity and the impact on them of seed treatment and foliar nutrition, taking into account the conditions of the Forest-Steppe right bankof Ukraine. The research was conducted in the research field of Vinnytsia National Agrarian University in the village of Agronomichne, Vinnytsia district during 2016–2018. Sinyukha variety was sown (2010). There has been established that the use of pre-sowing treatment of seeds and crops of Medicago sativa with biostimulant and microfertilizer improves the conditions of growth and development of the crop and increases individual productivity. On the researches it is established that fodder productivity of Medicago sativa sowing is provided by application of biostimulators of growth and microfertilizers on crops, genetic potential the culture realized as much as possible on the 2nd year of cultivation. The effect of growth stimulants on Medicago sativa productivity was defined and the optimal combination of macro- and microelements in modern complex fertilizers was determined, which contributes to the maximum possible yield of Medicago sativa green mass. New technological regulations for the use of bioorganic preparations and components in the technological scheme of Medicago sativa cultivation have been developed. It was found that on average for three years of vegetation of Medicago sativa sown on gray forest soils in the Forest-Steppe Right Bank, the highest yield of seeds and green mass provides the option of treatment with biostimulator Saprogum® and microfertilizer Wuxal®. Creating optimal conditions for mineral nutrition for Medicago sativa plants through the use of bacterial fertilizers and foliar nutrition contributed not only to the formation of high grain yields, but also significantly improved biochemical parameters and, consequently, increased crude protein content in grain, which is important for solving the problem of vegetable protein and balancing the diets of farm animals. The research results are aimed at solving current problems of technological renewal and development of agro-industrial complex on the basis of development of bioorganic models of varietal technology of Medicago sativa cultivation with orientation at the level of adequate arable productivity and climate fertility.
Airflow profile study of a compost dairy barn using a low-cost 3D-printed anemometer network
(2020) Vega, F.A.O.; Rios, A.P.M.; Damasceno, F.A.; Saraz, J.A.O.; Nascimento, J.A.C.
Mechanical ventilation is commonly used for environmental thermal regulation inside closed-field agricultural production systems. Analyzing the air distribution inside these facilities and the correct operation of the fans can be a challenging. This could be determined using cost prohibitive techniques as particle image velocimetry or deploying large wind sensors networks on-site. To avoid this limitation without a lack of measurement accuracy, this research was focused on developing and test a low-cost anemometer network based in low cost propeller’s anemometers, built using fused 3D-printed and open-hardware platforms. Four propeller anemometers with three to six blades were simulated using the 6-DOF method of ANSYS computer fluid dynamics software. Similar results were obtained for all the simulated models with minor differences. Anemometers were tested in an open circuit wind tunnel before to be evaluated in two open compost dairy barn building using high-volume low-speed and low-volume high-speed fans. Data were analyzed by employing contour maps, descriptive statistics and correlation. The results show that the anemometer network determines the fan’s wind profile for wind speeds over 0.7 m s-1 and it was possible to determine the facilities spots with ventilation problems. The proposed anemometer network and methodology are a good alternative to analyze the operating conditions of the tested agricultural facilities and optimize its performance.
Analysis of safety indicators for poultry products produced in subsidiary farms in penitentiary facilities
(2020) Chernikova, O.; Pityurina, I.; Terentyev, A.; Rakhmaev, E.
The production of poultry, eggs and their processed products is growing rapidly worldwide. Poultry products are in great demand; however, they are a source of a number of risks: physical, chemical, as well as microbiological. Ensuring food safety is currently the main aspect for the global food industry, including for the production of poultry products. The article discusses the safety and quality of poultry products produced in subsidiary farms of correctional facilities of the penal system. Attention is drawn to the risks and threats of sanitary and epidemiological well-being that arise in connection with the intensification of the impact of negative environmental factors. In the subsidiary farms of correctional facilities, the cage-type bird keeping system and the frequency of feeding are regulated depending on the age of the bird. The results of the analysis have shown that poultry and chicken eggs comply with established sanitary standards. Thus, the average heavy metal content in poultry meat was: Hg - 0.0061 mg kg-1 , Cd - 0.0233 mg kg-1, As - 0.0501 mg kg-1, Pb - 0.1765 mg kg-1; in the egg: Hg - 0.0072 mg kg-1 , Cd - 0.0198 mg kg-1, As - 0.0485 mg kg-1, Pb - 0.1812 mg kg-1. Antibiotics, radionuclides and dioxins were not found in poultry meat. The pesticide content in poultry meat was below the permissible level: by 2.2 times of DTM and its metabolites, and hexachlorocyclohexane (a, b, g - isomers) - by 5 times. Coliforms, Staphylococcus aureus, Proteus, as well as pathogenic salmonella, listeria were not found in poultry meat and eggs. NMAFAnM in meat amounted to 0.5×104 , in the egg - 1×103 CFU g-1 incl. In general, poultry products produced in correctional facilities are of high enough quality and can be used to prepare various dishes not only for adults but also for baby food. These estimates allow us to conclude about a fairly high level of quality and safety of this product.
Analysis of the selective value of promising Melissa officinalis L. subsp. altissima (Smith.) Arcang variety
(2020) Nevkrytаya, N.V.; Pashtetsky, V.S.; Novikov, I.A.; Petrishina, N.N.; Mishnev, A.V.; Repetskaya, A.I.
The aim of this research was to study a promising MD 1–17 Melissa officinalis L. subsp. altissima (Smith.) Arcang. variety sample obtained in the collection of the gene pool of the Research Institute of Agriculture of Crimea (RIAC) in comparison with Krymchanka (selected in the RIAC) and Lada (selected in the All-Russian research Institute of medicinal and aromatic plants(VILAR) varieties of lemon balm M. officinalis L. subsp. officinalis. In 2017– 2019, in the Department of Essential Oil and Medicinal Plants of the RIAC,a competitive variety trial of lemon balm varieties was conducted in accordance with the methodological recommendations for the selection of essential-oil plants. A territory where this study was conducted belongs to one of the five agroclimatic regions – the upper piedmont, warm, not enough humid; to the northern subarea with moderately mild winters. Weather conditions during the years of competitive variety trial varied significantlya fact that allowed assessing the adaptability of studied variety samples and forecasting the nature of productivity potential realization in different growing conditions. As a result, it was found that MD 1–17 variety sample significantly exceeds other varieties in terms of yield of fresh raw materials, on average, by 62.2 and 77.4%, and in yield of air-dried raw materials, on average, by 32.2 and 52.2%, respectively. In terms of obtaining essential oil from air-dried raw materials, this variety sample exceeds the best in this parameter Crimean variety Krymchanka by 56.3%. Basic components of its essential oil are caryophyllene (25.3–35.9%) and germacrene D (17.7–31.2%) with almost complete absence or insignificant amount of citral (0.1–7.3%); the proportion of latter in essential oils of Krymchanka and Lada varieties can reach 36.6% or more. Novelty of this study includes the creation of the first variety of a new promising essential oil plant –M. altissima. Raw materials of this variety and products of its processing may be of interest for different ways of use, including the perfumery and cosmetics industry, for food purposes as a component of tea compositions, etc.
Antioxidant content of dark colored berries
(2020) Ozola, B.; Dūma, M.
Blackberries (Rubus caesius), elderberries (Sambucus nigra L), highbush blueberries (Vaccinium corymbosum L) and black currants (Ribes nigrum) were selected for research on their content of phenolic compounds, including anthocyanins and comparing their content in these berries. Samples were also assayed for ascorbic acid and soluble solid content. The unifying mark of these fruits is purple-black color, which indicates high content of anthocyanins. Analyses of these fruits showed that they contain high biological activity components that justify the uses of these fruits. The research was done at the Department of Chemistry, Latvia University of Life Sciences and Technologies, year 2019. Berry samples were bought at the supermarket (highbush blueberries) or collected from garden in Jelgava, Latvia (blackberries, elderberries and black currants). All berries were at full maturity. The content of ascorbic acid, total phenols, anthocyanins, flavonoids as well as soluble solids was determined. Descending order of ascorbic acid content in berries is: black currants > blackberries > elderberries > highbush blueberries. Elderberries had the highest content of anthocyanins, total phenols and flavonoids on average 161.5, 537.9 and 112.6 mg 100 g -1 FW, respectively. The content of soluble solids changes from 5.83 Brix (elderberries) to 13.67 Brix (black currants).
Aphid complex associated with potato in agro-climatic conditions of Kosovo
(2020) Musa, F.; Krasniqi, D.; Musa, S.
Field surveys for aphids infesting potato crops in three most important localities for potato production in Kosovo (Podujevë, Prishtinë and Vushtrri) were conducted in vegetation seasons of 2018–2019. With the purpose to monitor and confirm the aphid composition in potatoes, aphid leaf count was used as a method which is applied worldwide. Sampling for aphids from the leaves of potato plants was undertaken during cropping season, every 10 days, where 100 leaves were taken at random and checked in triplicates, from each field. During of this experimental work, the following aphid species were registered Myzus persicae, Macrosiphum euphorbiae, Aphis nasturtii and Aulacorthum solani. From the total number of aphids recorded (4,210 individuals), the following percentage belongs to the different aphids: M. persicae (57.24%), A. nasturtii (25.72%), A. solani (7.77%), M. euphorbiae (5.68%), and other none identified aphids (3.59%). Relying on the results of this research we have confirmed to exist statistical significant differences with regard to the number of aphid’s species according to the localities and aphids that infests the potatoes. With the goal to manage and control aphids spread infields with potatoes, it is extremely useful to evaluate and to see the possibility for an Integrated Management against these pests at farmer level.
Application of feature selection for predicting leaf chlorophyll content in oats (Avena sativa L.) from hyperspectral imagery
(2020) Żelazny, W.R.
Feature selection can improve predictions generated by partial least squares models. In the context of hyperspectral imaging, it can also enable the development of affordable devices with specialized applications. The feasibility of feature selection for oat leaf chlorophyll estimation from hyperspectral imagery was assessed using a public domain dataset. A wrapper approach resulted in a simplistic model with poor predictive performance. The number of model inputs decreased from 94 to 3 bands when a filter approach based on the minimum redundancy, maximum relevance criterion was attempted. The filtering led to improved prediction quality, with the root mean square error decreasing from 0.17 to 0.16 g m-2 and R 2 increasing from 0.57 to 0.62. Accurate predictions were obtained especially for low chlorophyll levels. The obtained model estimated leaf chlorophyll concentration from near infra-red reflectance, canopy darkness, and its blueness. The prediction robustness needs to be investigated, which can be done by employing an ensemble methodology and testing the model on a new dataset with improved ground-truth measurements and additional crop species.
Applying beetroot as food ingredient in ice-cream production
(2020) Evstigneeva, T.; Iakovchenko, N.; Kuzmicheva, N.; Skvortsova, N.
The development of new food products with functional ingredients of plant origin is highly promising and relevant direction in food industry. Assortment of products, including ice cream is constantly expanding due to the introduction of various plant ingredients into its composition, enriching the product with health beneficial nutrients. In this study, beetroot (Beta vulgaris) was selected as a plant component for ice cream production. The roots of common beets contain many useful inorganic and organic substances, such as carbohydrates, proteins, organic acids, mineral salts, betalaines, vitamins, folic acid and betaine. The influence of different thermal treatment techniques of beetroots on the content of dry substances and organoleptic properties of beetroot puree have been compared and analyzed. The heat exposure technique recommended for beetroots is microwave processing for 9 minutes at a power of 800 watts. This method of heat treatment ensures the culinary readiness of vegetable raw materials while preserving dry substances in it, including betanine. The effect of the beetroot puree dose on the formation of the ice cream quality was studied. The recommended dose of the beetroot puree was established as 20%.
Assessment of management effect on grasslands characteristics in an area of the Apennines (North Italy)
(2020) Argenti, G.; Del Serra, F.; Staglianò, N.; Battaglini, I.
In many regions of Europe, semi-natural grasslands not properly utilized face different threats, concerning changes in botanical composition and structural evolution, which can lead to a reduction of the qualitative value of forage biomass or, in the mid-long term, forest recovery. The present paper assesses various semi-natural grasslands within a mountain public property located in Tuscany (North Apennines, Italy) subjected to different types of utilization. Some of them are managed through cattle grazing during summer, whereas some others are only periodically mowed and utilization is performed only by wildlife occurring in the area. The paper analyses the importance of resource management and its impact on botanical composition and on qualitative value of forage production. Data collection of studied areas was conducted by means of vegetation assessment performed with a fast procedure that simplifies the botanical composition sampling. Results show the relevance of some environmental factors on grasslands evolution and on their composition (such as altitude and slope) and the importance of management on grassland quality and on level of shrub encroachment.
Assessment of spatial variability of environmental variables of a typical house of laying hens in Colombia: Antioquia state Case
(2020) Ferraz, P.F.P.; Gonzalez, V.C.; Ferraz, G.A.S.; Damasceno, F.A.; Osorio, J.A.S.; Conti, L.
This paper aimed to analyze the magnitude and spatial variability of environmental variables: Temperature and Relative Humidity Index (THI), Radiant Thermal Load (RTL), Globe Temperature and Relative Humidity Index (BGTH) and Enthalpy (H), inside a house for laying hens, in the state of Antioquia (Colombia) during the month of August. A traditional Colombian poultry house with natural ventilation was used. All variables were manually measured at equally spaced 1.0×1.0 m points, totaling 99 data collection points inside the poultry house. Geostatistical techniques were used through semivariogram analysis, and isochore maps were generated through data interpolation by kriging. The semivariogram was fitted by the restricted maximum likelihood method. The used mathematical model was the spherical one. After adjusting the semivariograms, the data were interpolated by ordinary kriging. The semivariograms and the isochore maps allowed identifying the non-uniformity of the spatial distribution of all evaluated variables throughout the poultry house. The results show that THI, RTL, BGTH and, H presented values above the comfort limits in the most significant part of the poultry house during the observed period. It is possible to concluded that the use of natural ventilation alone was not sufficient to guarantee the homeothermy conditions for the layers. Thus, it is suggested that in addition to natural ventilation, secondary modifications should be used to improve farm productivity.
Assessment of the methane emission for different typologies of fattening swine facilities in the department of Antioquia – Colombia
(2020) Castrillón, N.; González, V.; Osorio, J.A.; Montoya, A.P.; Correa, G.
The explosive growth of swine production at high stocking densities in confinement farming worldwide, has raised concerns the environmental impact, health and livestock productivity and the production of associated gases in this type of large-scale farms. The aim of this paper was to study the methane gas concentration and emissions of ten different typologies of swine production installations. The facilities were in the department of Antioquia - Colombia, they were located between 800–2,300 meters above sea level (m.a.s.l.) of heights, they mainly employed natural ventilation as refrigeration strategy and they were used for pigs in fattening stage. Methane measurements were taken at animal height. Sensors were located at intermediate points of the ventilation inlet and outlet areas. The behaviour of methane concentration and emission of the facilities were analysed along with the correlation and temporal evolution of climatic variables, comfort indices and construction typologies. The information was analysed using descriptive statistics, analysis of variance (ANOVA) and principal component analysis (PCA). Were found an average of CH4 Emission Rate (ER) per facility (kg year-1 ) of 607.9, Global Warming Potential (GWP) per facility (kg year-1 ) of 15,197.42 and significant correlations between ER and cleaning frequency (CF), animal unit (AU), air flow (Q), animal density(AD) and relative humidity (RH) were evidenced. This is the first research reported in Colombia, that will be important to create some governmental policies.
Association between body condition and production parameters of dairy cows in the experiment with use of BCS camera
(2020) Chlebowski, J.; Gaworski, M.; Nowakowski, T.; Matusiak vel Matuszewski, B.
Dairy production effectiveness in the farm depends on many technical, technological and biological factors. State of the dairy cow condition constitutes one of the most important element in the assessment of dairy herd and production indices. Including access to modern technical solution to assess body condition of dairy cows, i.e. BCS camera, some results of observation in the herd with 362 cows were collected to find any relationship between BCS index and milk yield per cow including 5 lactation groups and cows differed in age as well as four seasons. Basing on data collected in the period of 11 months it was found that cows with the BCS index lower than 2.9 showed the highest daily milk production. Increase in BCS index was associated with decrease in amount of produced milk per day. The statistical analysis showed significant effect of lactation period, age of animals and season on BCS results in the considered dairy cow production cycle.
Atmospheric attenuation of the Ku band along the space-earth path due to clouds and rain
(2020) Dvořák, J.; Hart, J.; Kumhálová, J.
The weather conditions formed in troposphere causes the greatest signal attenuation in satellite communication systems especially at frequencies above 10 GHz. This paper describes possible signal attenuations on the satellite-earth path due to rain and clouds. It was measured whether it is advantageous to use the Ku band for data transmission over other bands. The measurement was carried out in the Czech Republic using a beacon signal from Eutelsat 12W satellite at 12.5 GHz. Clouds and the rainfall rate at the measured location were obtained from the CHMI portal. The measurements show that the clouds cause negligible attenuation. Significant attenuation was caused by rainfall. The measured values of slant path rain show a significant decrease in signal strength even in light rain. The measured cumulative rainfall rate was found to be close to the ITU-R model. The measurements show that the Ku band is advantageous for data transmission in rain poorer regions including Central Europe.
Biochar dosage impact on physical soil properties and crop status
(2020) Novák, V.; Křížová, K.; Šařec, P.
In the context of climate change and the ongoing population growth, current agriculture inevitably faces many challenges. Long periods of drought are often followed by shorter periods of heavy precipitation and degraded soil is often unable to retain the rainfall water properly. Apart from common organic fertilizers, soil amendments are currently considered a promising solution that might improve soil quality. The most discussed one is biochar, a natural soil conditioner that might under certain conditions improve soil properties. This study is based on the experiment that was established in 2017 in order to determine the impact of biochar dosage and it’s effect over time. Four parcels approximately 15×30 m were designed in Rapotín, Czech Republic. Each of them was treated with a specific dose of biochar (15, 30, 45, 60 t ha-1 ), and selected soil physical properties such as penetration resistance and reduced bulk density were then measured at the beginning of the cropping season 2019. In addition, vegetation properties were investigated with the use of handheld sensors repeatedly during the season on winter wheat. The dataset contained information about chlorophyll and nitrogen content as well as Normalized Difference Vegetation Index estimations. Acquired values were later compared with the results obtained from the fifth variant founded in 2014 with a 15 t ha-1 dose and from the control variant. Although the dosage levels applied were quite substantial, no significant difference was found when evaluating selected soil properties. Crop response gave similar results. Any of the examined characteristics differed among the 2017 variants and control. Nevertheless, when compared to the 2014 variant, clearly different results were detected. Thus, this study concluded that the effect of biochar dosage is might not be as significant factor, however, the time effect likely is. Therefore, the study has to continue and soil/crop properties will be observed in the upcoming season as well.
Biochemical composition and quality of herring preserves with addition of bio-protective cultures
(2020) Bazarnova, J.; Korableva, N.; Ozerova, O.; Moskvicheva, E.
Herrings rich in vitamins B12, A, D, minerals, including calcium, potassium, magnesium, iodine, possess high levels of lysine, tyrosine, phenylalanine and tryptophan, as well as omega-3 unsaturated fatty acids, namely eicosapentanoic, docosahexoenoic and docosapentoenoic. To suppress the microbiological spoilage of fish preserves, it is promising to use bio-protective cultures that have minimal impact on the production process and product properties. Bacterial strains are able to exert a static effect on the microflora, which causes biodeterioration of food products. Microorganisms as part of bio-protective cultures are included in the fermentation process, so they can be attributed to ordinary food ingredients, so there is no need to put separate information on the packaging. The chemical composition of the frozen Atlantic and Pacific herring fillet, the amino acid composition of proteins, and the fatty acid composition of lipids were studied. The difference between Atlantic and Pacific herrings was detected, which consists in a significantly higher content of docosahexaenoic acid. The difference in the fractional composition of triacylglycerols for the Atlantic and Pacific herring was established. The microflora of SafePro B-2 biological product (Chr. Hansen GmbH), containing multiple strains of Lactobacillus sakei, and the viability of the culture in preserves fillings were studied. The experimental development of canned food with SafePro B-2 additives was carried out. Microbiological, organoleptic and biochemical indicators of the preserves quality during cold storage were studied. The influence of introduced culture on the dynamics of preserves curing period and their shelf life was established.

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