The purpose of this study was to predict and compare salt accumulation in the soil profile under drained and undrained conditions. The water management simulation model, Drainmod (Ver. 6.1) was used to determine the optimal drainage system design parameters, which will decrease soil profile salinity and provide maximum crop yields in Ankara-Bala Basin of Turkey. Soil sampling points were coordinated with the Global Positioning System (GPS). Soil, crop and site parameters were obtained as an input. The model was run for 5 years from 2005 to 2010 to simulate optimum drainage design parameters (drain depth, drain spacing) while controlling soil salinity in the root zone. Soil water conditions and soil salinity level were simulated for crop rotation of corn (Zea mays) and winter wheat (Triticum). Yield of individual crops was predicted for each growing season. The results of the simulations were analyzed to identify alternatives of subsurface drainage system that would satisfy maximum crop productions. According to the simulation results, the drain spacing of 130 m and drain depth at 160 cm are recommended for Bala Basin. Soil salinity maps were created for undrained and drained conditions. Results showed that the soil salinity level and salinity stress can be reduced and yield increased by installing a drainage system.

Oat (Avena sativa L.) is one of the small grain crops produced in temperate climate zone. Common oat has been studied most often due to its multifunctional characteristics and nutritional profile. The main function of the oat husk is to protect grain from harmful conditions during harvesting and storage time. Oat grain size uniformity is an important parameter to the oat milling industry. The aim of this study was to compare the husk content of common oat cultivars grown in Latvia and to obtain its changes at different grain size fractions during three growing seasons. The field trial was carried out at the State Stende Cereal Breeding Institute from 2012 to 2014. Ten husked oat genotypes were studied. Oat samples were fractioned into size fractions and samples of each fraction dehulled by hand. Results showed that significant (p is less than 0.05) differences in the husk content were observed among genotypes, growing season and different grain size fractions. Significantly lower husk content was for genotype ‘Arta’ in all growing seasons. For majority of used genotypes increasing grain size the husk content decreased.

Pisum sativum L. (field or garden pea), is widely cultivated in Europe. The purpose of this investigation was to see whether pea varieties differ in their yield and content of protein and nutrients. Another aim was to select the best varieties suitable for breeding or production. A field experiment with different varieties of peas (‘Bruno’, ‘Capella’, ‘Clara’, ‘Mehis’ and ‘Vitra’) was carried out at the Estonian Crop Research Institute in 2014. Yields (t haE-1) were not statistically different. Crude protein content (g kgE-1 in dry matter) was lowest in ‘Clara’; all other varieties had a higher content of protein, within much the same range. The lowest N content was found in ‘Clara’, followed by ‘Capella’ and ‘Vitra‘, ‘Mehis’ (44) and the highest in ‘Bruno’ (45). The lowest P content was found in ‘Clara’, followed by ‘Capella‘ and ‘Vitra’; the highest was found in ‘Bruno’ and ‘Mehis’. The lowest K content was found in ‘Mehis’, then ‘Clara’, followed by ‘Capella’ and ‘Vitra’ and the highest in ‘Bruno’. The lowest Ca content was found in ‘Clara’, followed by ‘Capella’ and ‘Mehis’, ‘Vitra’, and highest in ‘Bruno’. The lowest Mg content was found in ‘Capella’, followed by ‘Clara’ and the highest in the other varieties ‘Bruno’, ‘Mehis’ and ‘Vitra’. Thus, choice of the right variety for pea cultivation is very important, but depends on the local agro-climatic conditions. This investigation has been developed with the help of the project EUROLEGUME, funded from the European Union Seventh Framework Programme for Research, Technological Development and Demonstration under the grant agreement no. 613781.

In Estonia, the most promising perennial grass used as raw material for production of heat energy is reed canarygrass (Phalaris arundinacea L.). Nordic countries (Finland, Sweden) implement a technology including single harvest of the above-ground biomass from frozen soil early in spring. This technology cannot be used in Estonia as the ground does not freeze to the extent of bearing harvesting machines every year. Harvesting in spring is virtually impossible as herbage lodges excessively under the snow weight. A divided harvesting method of reed canarygrass was tested in field trials in 2010–2013 at the Estonian Crop Research Institute. Herbages were cut in July at the height of 60–65 cm, mass was dried as hay, stubble hay was left to grow and was harvested next spring before the growth started but soil had become dry. The effect of seeding rate, row spacing and nitrogen fertilizer on the dry matter yield of reed canarygrass was investigated. The amount of produced heat by trial variants was calculated. The variant with narrow spacing (15 cm), seeding rate of 8 kg haE-1 and usage of fertilizer N70 in the beginning of growth and N70 kg haE-1 after the first cut was giving the best results. Two cuts of this variant yielded on average 8.12 t haE-1 per year, of which the stubble hay, harvested in spring and with better combustion properties, made 64%. Energetic value of the yield was 138 GJ haE-1 per year.

Sapropel or gyttja are the terms that relate to specific water body sediments containing a high level of organic matter formed from the remains of water biota mixed with mineral components. One of the most promising utilisation ways of sapropel is agriculture and forestry where this natural material can be used as soil amendment to enrich soil fertility, neutralise acidity, improve water capacity and reduce phytoavailablity of excess of metallic elements. The aim of this study was to perform plant germination and early seedling tests using various sapropel samples and to reveal response of plant development depending on the type of sapropel to be used as soil amendment. Pure natural sapropel and sapropel/sand substrate of such types as peaty, organic-sandy, cyanobacteria, green algae and carbonatic sapropel, derived from four lakes of eastern Latvia, were tested. Seeds of cucumber Cucumis sativus and tomato Solanum lycopersicum as dicotyledons and perennial rye-grass Lolium perenne as monocotyledon were chosen for the experiment. Seed germination and early seedling tests were performed in PHYTOTESTKIT plates. Seeds were germinated in thermostat at a temperature of 26 °C for 7 days but early seedling development was achieved after 23- 30 days (depending on plant species) under daylight conditions at a temperature of 20 °C. Developed radicles and hypocotyls were measured, shoots and roots were weighed. The obtained results showed a distinctive effect of applied sapropel type on the development of plants depending on species and substrate – substrate containing pure natural sapropel is effective for cucumber and perennial rye-grass, but not for tomato.

From legume seeds it is possible to make new products with different physical properties such as size and hardness by using extrusion-cooking. Peas are products that normally need a rather long cooking time, but extrusion-cooking can make them more usable in daily human diet. As protein based food products in markets are less represented than those based on carbohydrates, but for balanced diet protein intake is essential, our aim was to ensure availability of such products, so experiments were carried out in order to establish optimal moisture content for grey pea (Pisum sativum L.) flour extrusion. Three grey pea (Pisum sativum L.) based products were obtained with different water amount added before extrusion, and their size, volume mass and colour was analyzed in order to ascertain what amount of water is best for such products. Results show significant differences for size, volume mass and colour changes, establishing that the best of the products was the one with 9.00±0.01 g∙100gE-1 added water. This product had better characteristics than others, where 11.00±0.01 g∙100 gE-1 and 7.00±0.01 g∙100 gE-1 water was added. The products with 9.00±0.01 g∙100 gE-1 added water were by more than 100 g∙LE-1 lighter than other products, also colour changes compared to non extruded pea flour were fewer than for other samples and their size was the biggest of all obtained products, averagely 11±1mm.

Pea and buckwheat flours are gluten free and have high nutritional value; therefore they are advisable for frequent consumption. The addition of pea and buckwheat flours to products changes their nutritional value and technological properties significantly. The aim of the research was to investigate the starch content, colour and rheological properties of pea and buckwheat flours and their blends. Results showed that pea flour had a higher content of starch than wheat and buckwheat flours, pea-buckwheat flour blends and formed the largest part of dry matter. The peak, holding, final, breakdown and setback viscosities of buckwheat flour, in turn, were significantly higher than those of wheat (control) and pea flours. Buckwheat flour provided higher peak, holding, final, breakdown and setback viscosities and lower starch gelatinization temperature in flour blends. The highest lightness was demonstrated by the control sample, whereas the lowest by the buckwheat flour which had the highest redness value a* comparing with other flours and blends. Pea flour showed significantly higher yellowness b* in comparison with other samples, with the exception of flour blend with 60%PF + 40%BF. Colour values could be changed significantly by blending buckwheat and pea flours. It is possible to increase L* and b* values of buckwheat flour with pea flour and a* value of pea flour with buckwheat flour in flour blends. Results of farinograph showed that buckwheat flour was characterized by a long development time; high stability and high farinograph quality number (FQN), whereas pea flour and pea-buckwheat flour blends had short development time, low stability and low FQN.

Kvass is a non-alcoholic beverage produced by fermenting kvass mash with yeast; alcohol content in kvass must be less than 1.2% by volume. Kvass extracts have longer shelf-life and they are essentially free of ethanol. The aim of this research was to evaluate and compare aroma compounds in naturally fermented kvass and kvass extracts. Experiments were carried out at the Latvia University of Agriculture, Department of Food Technology from November 2014 to February 2015. Three commercially available kvass samples (Bruveris, Bauskas and Liepkalni) were used to produce kvass extracts applying vacuum evaporation. The investigation of volatile compounds in kvass and kvass extracts was performed using solid phase microextraction and gas chromatography mass spectrometry. Dry matter content in kvass extracts was 32.4 ± 0.3% (ISO 2173:2003). In all kvass and extract samples in total 25 volatile compounds were detected. Ten of them were esters, five alcohols, five acids, four aldehydes and three ketones. Such aroma compounds as ethyl acetate (fruity flavour), hexyl acetate (fruit, herb) and ethyl decanoate (grape) were found only in Bruveris kvass, 2,3-butanedione (buttery) and phenethyl butyrate (floral) were found only in Bauskas alus kvass and three volatile compounds were identified only in Liepkalni kvass – acetic acid (sour), furfuryl alcohol (burnt) and carvone (caraway). Less than a half of the main aroma volatiles in kvass were also identified in kvass extracts and total values of peak areas were significantly lower in kvass extracts compared to kvass (p = 0.01).

Whole grain flour can be considered as a good candidate for pasta fortification due to the health benefits. Literature reports pasta dough fortification with non-traditional ingredients and cereals. Therefore, the purpose of the current research was to investigate rheological properties of whole grain flour blends for pasta production. Flour blends were made from wheat flour (type 405) in a combination with other flours (whole grain wheat, rye or hull-less barley flour) in various proportions (from 10% to 50%). Wheat flour type 405 was used as a control. Rheological properties of dough were analysed using Farinograph AT (Brabender, GmbH and Co.KG., Germany) and starch gelatinization properties of flour starch using Amylograph-E (Brabender GmbH and Co.KG., Germany); moisture content of flour samples (AACC 44-15A from 2000). The results of present research demonstrate that rheological properties of dough decrease if the amount of whole grain flour in blend increases. It was concluded that water absorption and dough development time of dough with whole grain flour blends addition is less than the parameters of control wheat flour (type 405). However, a higher starch gelatinization was obtained for flour blends with whole wheat grain flour, comparing to blends with whole rye and hull-less barley grain flour, which mainly could be explained with a higher gluten content of whole wheat grain flour.

In this work the combinations of commercial lactic acid bacteria starters and acetic acid bacteria strain were used for production of fructans in substrate, both with and without sucrose additive, and studied their potential in maintaining technological properties of yoghurt and fermented milk. The objective of this study was to assess the effect of fructans producing starter cultures on milk coagulation technique, the amount of secreted fructans and viscosity of fermented milk samples. An amount of fructans synthesized by starter cultures and Gluconobacter sp. B35, pH and viscosity of samples were measured using appropriate standards and analytical methods. Results showed that the addition of acetic acid bacteria did not influence the pH dynamics of fermented milk samples. Increasing sucrose concentration in samples significantly influences fructans production potential. The application of such technology in fermented dairy product production would have potential from microbiological exopolysaccharides increasing position with the aim to promote functionality of dairy foods and to substitute commercial stabilisers etc. The addition of acetic acid bacteria in milk showed negative impact on viscosity of the evaluated samples. The viscosity was liquid in all analyzed samples with acetic acid bacteria, the addition of sucrose helped to make the consistency of yoghurt and fermented milk more liquid. We concluded that the structure of synthesized fructans could not help to improve the textural properties of fermented dairy products. From this point of view, the studied acetic acid bacteria strain should have the potential as prebiotic.