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Quality of specialty coffee: balance between aroma, flavour and biologically active compound composition: review Полный текст
2018
Laukaleja, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Specialty coffee, according to Specialty Coffee Association of America (SCAA) standards, is coffee which has been standardized from the coffee plantation process until its delivery to the consumer, in compliance with all quality standards, to highlight the characteristics of the beverage. With increasing coffee consumption, more attention is focused not only on the flavour and texture of the drink, but also on the impact of coffee on health. The beneficial effects of coffee on human health are mainly based on a wide range of biologically active components. The coffee composition of the biologically active compounds and flavour compounds are influenced differently by almost all technological processes. The aim of this review was to summarize recent scientific developments about composition of aroma, flavour and biologically active compounds in specialty coffee and evaluate the best possibilities to balance health promoting and flavour attributes. Specialty coffee mainly focuses on fruity, floral, sweet and acidic notes in coffee, which are opposite to phenolic compound aroma characteristics during roasting process. In conclusion, roasting temperature significantly influences all biologically active compounds and important aroma, flavour volatiles in coffee. All compound concentration, except coffee melanoidins, decreases during roasting process. Light-medium roast level could provide stability among floral, fruity aroma, flavour notes and biologically active compounds (phenolic compounds and coffee melanoidins) in coffee.
Показать больше [+] Меньше [-]Dynamics of Coxiella burnetii DNA in milk and phase-specific serological response in dairy cows Полный текст
2018
Ringa-Karahona, G., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Antane, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)) | Grantina-Ievina, L., Institute of Food Safety, Animal Health and Environment „BIOR”, Riga (Latvia) | Steingolde, Z., Institute of Food Safety, Animal Health and Environment „BIOR”, Riga (Latvia) | Trofimova, J., Institute of Food Safety, Animal Health and Environment „BIOR”, Riga (Latvia)
In dairy cows shedding of Coxiella burnetii in milk can be persistent, sporadic to absent. Persistent heavy shedder cows are mostly highly-seropositive. Serological response due to C. burnetii antigenic phase demonstrates acute or chronic infection (serological response to phase II (PhII) or phase I (PhI) antigen, respectively). The aim of this study was to detect dynamics of C. burnetii DNA in milk and phase-specific serological response. In this study, the sera samples from 46 animals and milk samples from 34 were collected initially. Milk and sera samples from 36 animals were collected repeatedly. Samples were collected in five herds with previous history of C. burnetii infection from different parishes in Latvia – in 2017 and 2018. Milk samples were tested by detection of C. burnetii DNA by realtime PCR amplification using ‘ADIAVET™ COX REALTIME’ (ADIAGENE). Sera were tested by ‘VetLine Coxiella Phase1 and Phase2 ELISA’ (NOVATEC). Three cows (9%) in the first sampling and five (14%) in second sampling demonstrated shedding of C. burnetii DNA in milk . Six cows (13%) in the first sampling and eight (22%) in second sampling demonstrated positive serological response to PhI. Three cows (7%) in the first sampling and one (3%) in second sampling demonstrated a questionable serological response to PhI. Two cows (6%) in the second sampling demonstrated a questionable serological response to PhII . In herds with previous history of C. burnetii infection the number of animals demonstrating PhI positve serological response increases significantly (p0.05) during six months. In cows demonstrating positive serological response to PhI it continues and mostly remains unchanged during six months.
Показать больше [+] Меньше [-]Barbarea arcuata as a potentially expansive species in agricultural landscapes in Latvia Полный текст
2018
Rurane, I., University of Latvia, Riga (Latvia). Botanical Garden;University of Latvia, Riga (Latvia);Daugavpils Univ. (Latvia) | Roze, I., University of Latvia, Riga (Latvia)
The distribution and abundance of Barbarea arcuata (Opiz ex J. et C. Presl) Rchb. were investigated throughout the territory of Latvia. The field survey was carried out to estimate the abundance patterns, and the herbarium materials were used to compile a distribution map. In total 411 localities were recorded in the period from 2015 to 2017. The species has been commonly found on roadsides, which accounts for 66% of the localities. Seventeen percent of the localities occurred in grasslands, 10% – in croplands, 4% – in fallows, 2% – on road embankment slopes, and 1% – on railway embankments. The highest density of B. arcuata were found in new fallows where it forms large populations. Whole field localities account for 5% of the total localities. Medium-sized stands are found in about 20% of localities and are mostly found in grasslands, roadsides, as well as croplands which include cereal fields and oilseed rape fields. Individual specimens are mostly found on roadside habitats and grasslands and account for 75% of the total number of localities. As dominant weed species it is found on fields of oilseed rape, cereal fields and fallows. Herbarium data and the Institute of Biology, University of Latvia lists of species show that B. arcuata distribution was frequent during the period from 1970 to 2014.
Показать больше [+] Меньше [-]Productivity of crop rotation measured as energy produced by included plants: a review Полный текст
2018
Darguza, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Gaile, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The most important reason for growing field crops is food consumption. Only some of the total amounts of field crop species are mostly used for cultivation in the largest part of arable land. These crops ensure high economic income. This is the reason why biological diversity has decreased. Crop rotation is considered to be an instrument of sustainable cropping system and this is confirmed again nowadays. Higher cereal yields have been gained by including oil crops or pulses in the rotation. Each field crop has its own calorific value (MJ kgE-1). Grains/seeds and above-ground biomass may have different calorific values because of their chemical composition. Research results from literature confirm that the average net calorific value of winter wheat (Triticum aestivum) and triticale (Triticosecale) grain and straw are ~17 MJ kgE-1, but the net calorific values for oilseed rape (Brassica napus ssp. oleifera) seeds and straw are – 25.70 MJ kgE-1 and 16.37 MJ kgE-1, respectively. Oilseed rape is also known as energy rich crop. It is reported that diversified crop rotations also have greater energetic productivity from above-ground biomass (grain/seed yield and by-products) if compared with crops grown in repeated sowings or in monoculture. Crop rotation in combination with different tillage methods (conventional tillage, reduced or minimum tillage and no-tillage) is the way to improve soil quality, but it is not clear whether the soil treatment method has a significant impact on the overall crop rotational energy productivity.
Показать больше [+] Меньше [-]Amino acids content in triticale grain depending on meteorological, agrotechnical and genetic factors Полный текст
2018
Jaskiewicz, B., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Szczepanek, M., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
The field studies were conducted in the years of 2011 and 2014 at the Experimental Station in Osiny, Poland. Triticale (Triticosecale) is a valuable fodder cereal with a high nutritional value of grains. It can also gain importance as a consumer cereal, providing the body with the necessary amino acids. The aim of the study was to determine the influence of precipitation and temperature conditions in the harvest year, agronomic factors (intensive or integrated type of production) and the percentage of cereals in crop rotation (50, 75 and 100%) on the amino acid content of two winter triticale cultivars (‘Pizarro’ and ‘Pigmej’) as well as to determine the nutritive value of the protein: chemical score (CS) and essential amino acid index (EAAI). Our studies have shown that although the amino acid content of winter triticale is strongly genetically determined, it also depends on weather and agrotechnical factors. Precipitation and temperature factors had the biggest effect on the tyrosine (Tyr) content. The contents of essential and non-essential amino acids in triticale grains and EAAI value were higher under intensive technology, with 50% of cereal grains in the crop rotation, and in the traditional cultivar ‘Pizarro’ as compared to the dwarf one ‘Pigmej’. The most important amino acids that limit the quality of protein in the grain are lysine (Lys) and tryptophan (Trp). Using intensive technology, reducing the cereal percentage of cereals in the crop rotation and selecting a proper cultivar, it is possible to maximize the content of the desired essential and non-essential amino acids in the triticale grains, and thereby improve their feed and consumer value.
Показать больше [+] Меньше [-]The influence of production technology on yield and selected quality parameters of spring wheat cultivars Полный текст
2018
Sulek, A., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Cacak-Pietrzak, G., Warsaw Univ. of Life Sciences (Poland)
The field experiments were conducted at the Institute of Soil Science and Plant Cultivation – State Research Institute Experimental Station in Osiny in the years of 2015 – 2016. The aim of the study was to compare spring wheat (Triticum aestivum L.) yield depending on an integrated and intensive technology. The used production technologies differed as regards the nitrogen fertilization level, chemical protection against weeds, diseases, pests and the way of straw utilization. The following cultivars were selected for the research: ‘Arabella’ and ‘KWS Torridon’. The weather conditions differentiated the yield of spring wheat in individual years. A higher effectiveness of intensive technology, expressed with a higher grain yield compared to the integrated one, was recorded in 2015 – on average by 18.0%. The yield increase between intensive and integrated technologies resulted from a higher 1000 grain weight. Spring wheat cultivars showed a varied response to the production technologies used. Under the intensive technology, a significant yield increase was recorded for the cv. ‘KWS Torridon’, while the production technologies did not differentiate the yield of cv. ‘Arabella’. The quantity and quality of protein substances and the activity of amylolitic enzymes in grains were more dependent on the cultivar than on the production technique used. In the case of spring wheat cultivars ‘Arabella’ and ‘KWS Torridon’, the integrated production technology ensures obtaining grains of the quality suitable for processing.
Показать больше [+] Меньше [-]The effect of superabsorbent polymer application on yielding of winter wheat (Triticum aestivum L.) Полный текст
2018
Grabinski, J., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Wyzinska, M., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland)
Superabsorbents are hydrophilic polymers that can absorb large amounts of water. These studies show that the use of superabsorbent may significantly reduce the negative effects of drought stress on plants. However, their use in the field cultivation has so far been minimal. The price of hydrogels has recently decreased significantly. This was the reason for starting research described in this work, in which the experimental plant was the winter wheat cultivar ‘Lucullus’ – the cereal which is the most intensively cultivated in Poland. The field experiment was conducted in the years of 2014 – 2016, in the Agricultural Experimental Station (AES) in Osiny, Poland, in 4 repetitions. TerrahydrogelAqua was evaluated in the following doses: 1) control without hydrogel, 2) 10, 3) 20 and 4) 30 kg•haE-1. Before harvesting, the plant samples were taken to determine the yield structure elements. After harvesting, grain yield at 15% moisture content was determined. The influence of hydrogel on winter wheat grain yield varied in individual years. On average, the yield of wheat grain from the treatment with a dose of 30 kg•haE-1 of hydrogel was significantly higher than from the control treatment or the treatment with a dose of 10 kg•haE-1 of hydrogel. The mean values of yield structure features, i. e. ear grain yield and weight of thousand grain were the highest at the dose of 30 kg•haE-1 of hydrogel. The effect of hydrogel on the average number of plants and ears per unit area and on the number of grains per ear was not found.
Показать больше [+] Меньше [-]Temporal variability of drought in field crops in the region of Kujawsko-Pomorskie, Poland Полный текст
2018
Kusmierek-Tomaszewska, R., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Dudek, S., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Zarski, J., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Januszewska-Klapa, K., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
The objective of the work, carried out as part of research programme on current change of the regional climate, was to confirm the hypothesis about the increasing frequency and intensity of droughts in May and June in the region of Kujawsko-Pomorskie (central Poland) in the years 1981 – 2010. Furthermore, the aim was to confirm a significant relationship between indicators characterizing meteorological and agricultural droughts. Material for the research was the data from five meteorological measuring points located in the region. Atmospheric precipitation and air temperature in the period of high water needs of cereals and rapeseed (May–June) were used. Statistical methods widespread in climatological studies were applied, particularly the method of trends. The average multiannual totals (1981–2010) of rainfall in May–June allow ranking the region of Kujawsko-Pomorskie into the area of the lowest rainfall in Poland. The frequency of meteorological drought in May and June is 23.3–30.0% in the region. In the analysed period there were no significant changes in the frequency and intensity of these droughts with the passage of years. Rainfall shortages in cereal crops and rapeseed production range on average from -19 to -35 mm, and extend to maximum of -93 to -117 mm. The values of shortages did not show any significant changes in the years of the study. The significant dependence between the indicators of meteorological and agricultural droughts allows for determination of the rainfall shortages in crop production on the basis of the SPI values.
Показать больше [+] Меньше [-]Leaf optical properties reflect changes of photosynthetic indices in apple trees Полный текст
2018
Lauzike, K., Lithuanian Research Centre for Agriculture and Forestry, Akademija, Kedainiai distr. (Lithuania) | Samuoliene, G., Lithuanian Research Centre for Agriculture and Forestry, Akademija, Kedainiai distr. (Lithuania);Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The impact of light penetration into crown and the effect of rootstocks and distance between trees on photosynthetic behaviour were analysed. Apple cultivar ‘Auksis’ was grafted onto dwarfing rootstock P60 and super-dwarfing rootstock P22 and planted at different distances (3 × 1 m, 3 × 0.75 m and 3 × 0.5 m). Nitrogen balance index and photochemical reflectance index were measured at two heights: 0.8 m above ground inside the canopy and 1.5 m above ground outside the canopy; specific leaf area, fresh and dry weight were evaluated from all canopy. The significantly positive effect of dwarfing rootstock P60 on all tested indices was observed comparing to P22 rootstock. Increasing density between trees lead to a decreased specific leaf area and increased nitrogen balance index. The dry and fresh weight ratio and photochemical reflectance index were also significantly affected, but no general tendency was identified. Photochemical reflectance index was not affected by light penetration into canopy, but the nitrogen balance index significantly decreased in the upper part of the canopy. Summarizing, it can be stated that decreasing light penetration into the crown results in an increase in the specific leaf area and photochemical reflectance index, and leads to a decrease in dry and fresh weight ratio and nitrogen balance index.
Показать больше [+] Меньше [-]The effects of LED lighting on nitrates, nitrites and organic acids in tatsoi Полный текст
2018
Simanavicius, L., Lithuanian Research Centre for Agriculture and Forestry;Akademija, Kedainiai distr. (Lithuania);, Akademija, Kedainiai distr. (Lithuania);Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Virsile, A., Lithuanian Research Centre for Agriculture and Forestry
Progressive type of controlled environment horticulture, such as plant factories, enables the precise control of cultivation environment parameters. The experiments were performed at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in the year of 2017. The aim of this study was to evaluate the effects of different irradiance levels produced by solid state light-emitting diodes (LEDs) on nitrates, nitrites and organic acids contents in tatsoi (Brassica rapa var. rosularis), cultivated in the controlled environment chambers. Plants were cultivated under combinations of red (640, 660 nm), blue (445 nm) and far red (731nm) LEDs at photosynthetic photon flux density (PPFD) level of 200 µmol mE-2 sE-1. At the pre-harvest stage, PPFD was increased to 300 µmol mE-2 sE-1 by elevating the fluxes of different spectral components for 3 days. The contents of nitrates, nitrites and organic acids were evaluated. The results propose the metabolic interface between nitrates, nitrites and organic acids in green vegetables, sensitive for lighting conditions. The higher intensity of LED light at pre-harvest stage led to decreased contents of nitrates in tatsoi. The increased intensity of blue 455 nm light led to lower contents of nitrates and higher of organic acids in comparison to red 640 nm. In addition, the increased intensity of red 640 nm led to significantly higher (p≤0.05) contents of nitrites. The target management of LED light spectra and intensity at pre-harvest stage could be used to reduced nitrates and increased organic acids in tatsoi.
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