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Effect of organic and conventional production system on the quality of spring wheat
2012
Tein, B., Estonian Univ. of Life Sciences, Tartu (Estonia)
Field trials with the spring wheat (Triticum aestivum L.) were carried out on the experimental fields of Estonian University of Life Sciences in 2011. The yield quality (volume weight, 1000 kernel weight, falling number, gluten content, gluten index, gluten content in dry matter) of spring wheat was studied in cultivar ‘Vinjett’. The wheat was part of the five-year crop rotation experiment where red clover (Trifolium pratense L.), spring wheat, peas (Pisum sativum L.), potato (Solanum tuberosum L.) and barley (Hordeum vulgare L.) undersown with red clover were following each other. There were three treatments which followed the crop rotation. In one treatment mineral fertilizers and pesticides were used, but other two treatments were organic without any synthetic agrochemicals. In mineral fertilizing treatments, the background of P25 and K95 kg ha-1 the N amount varied from 0 to 150 kg haE-1. Herbicides Sekator and MCPA 750 were used in conventional part. The aim of this research was to study red clover’s after-effect and different N fertilizer amounts’ influence on the spring wheat yield quality. In treatments where no mineral fertilizers were used and which only followed the red clovers after effect had higher gluten index and gluten content in dry matter. Higher mineral nitrogen amounts and organic treatments decreased spring wheat 1000 kernel weights and volume weights. The wet gluten content and falling number increased with increase of the amount of mineral N.
显示更多 [+] 显示较少 [-]Perennial grasses for bioenergy production: characterization of the experimental site
2012
Rancane, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
To promote the future of abandoned lands management and the reduction of fossil energy consumption in Latvia, the establishment of energy crops plantation facilities, including perennial grasses, was investigated. The objective – suitability of several perennial grasses for bio-energy production under condition of Latvia. The aim of the current research to evaluate the experimental field conditions for the cultivation of perennial grasses. The perennial grasses are modest in terms of soil conditions, they are environmentally friendly, as well as provide high yields of biomass with adequate quality for bio-energy production without large investments. With increasing amounts of bio-energy production the amounts of various by-products which are profitable to utilize as energy crops fertiliser will also increase. It is essential that plant nutrients return back into circulation by creating a complete cycle. In order to test in practice the possibility of creating this complete cycle of growing perennial grasses, an experimental field was chosen at the Research Institute of Agriculture in Skriveri. In the summer of 2011, before trials establishment, the conditions of soil were examined at four depths: 0 – 20 cm; 20 – 40 cm; 40 – 60 cm and 60 – 80 cm. The analyses showed that the experimental field conditions were appropriate for growing of perennial grasses. The results of the soil agrochemical analysis will be a base for future studies of usage efficiency of different fertiliser types on perennial grass productivity and nutrient recycling opportunities in energy crop plantations.
显示更多 [+] 显示较少 [-]Impact of slurry application method on sward yield and N and K leaching from grassland
2012
Mailiis, T., Estonian Univ. of Life Sciences, Tartu (Estonia)
Abstract Studies comparing slurry injection versus spreading have reported inconsistent results so far. The objective of the study was to compare two slurry application methods, injecting and spreading, in terms of influence on sward yields and leaching of nitrogen (N) and potassium (K) from grassland. The experiment was conducted from 2008 to 2011 at the Eerika Experimental Station, Estonian University of Life Sciences. Mini-lysimeters filled with loamy sand soil embedded in three swards (three-species grass mixture (Phleum pratense, Lolium perenne and Poa pratensis), grasses mixture with white clover (Trifolium repens), and grasses mixture with lucerne (Medicago sativa)) were used. Three annual nitrogen rates (60, 120, 180 kg haE-1) in conjunction with the two slurry application methods (injecting and spreading) were applied. Percolated water quantities, N and K content in leachate and the sward yield were measured. N leaching was significantly less with slurry injection while K leaching did not depend on slurry application method. N and K leaching was more affected by sward botanical composition and applied N rate and N:K ratio n slurry than by slurry application method. Sward yields did not depend significantly on slurry application method. Slurry injection is rational only in grasses sward when used N rates are above 120 kg haE-1 yrE-1. Slurry injection may have negative influence on the distribution of white clover in the grasses + white clover sward and thus lead to sward yield decrease.
显示更多 [+] 显示较少 [-]Milk urea content as indicator feed protein utilization and environmental pollution in farms
2012
Ruska, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Advances in milk production and the expansion of dairy herds have increased the need for improved manure management and whole farm nutrient balance. It is well known in dairy management that the balanced feeding and holding technology is an important level by which milk production and milk composition can be modified. The objective of this study was to evaluate urea content and urea yield in different farms with different holding technologies. Four farms represent three cow breeds (Holstein Black and White, Latvian Brown, and cross breed XP). Individual cow milk samples (n=2740) were collected monthly from September 2009 to November 2010. Milk samples were analyzed for total protein, casein, fat, lactose, and urea content with instrumental infrared spectroscopy method. The average milk yield per cows in farms was significantly different (from 27.9 to 17.0 kg per control day). The urea content in cow milk was between 20.3 to 46.6 mg dLE-1. The average urea content in farms A, B and D was up to standard (from 15.0 to 30.0 mg dLE-1). In the farm C, average urea content ranged between 17.4 and 79.9 mg dLE-1, which indicated problems in feeding or management in the farm. It was established that milk urea content and yield significantly (p is less than 0.05) varied in farms with different dairy cow holding and feeding technologies. Urea content can be used to evaluate feed protein utilization in farms and predict environmental pollution.
显示更多 [+] 显示较少 [-]Rehydration of dried Latvian cranberries affected by drying conditions
2012
Ruse, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Rakcejeva, T., Latvia Univ. of Agriculture, Jelgava (Latvia) | Berzina, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of the current research was to study the effect of drying conditions on the rehydration kinetics of Latvia wild grown and on cultivated cranberries. The research was accomplished on fresh wild cranberries and cultivated cranberry cultivars ‘Ben Lear’ and ‘Pilgrim’ harvested in Kurzeme region of Latvia in the first part of October 2010 and immediately used in the drying experiment. Three methods were used for pre-treatment of berries: perforation, halving and steam-blanching. Before drying in a convective drier the berries were pre-treated using all three methods and berries were dried in a microwave vacuum drier using two pre-treatment methods – steam-blanching and halving. Parts of berries were dried in the microwave vacuum drier without pre-treatment (whole berries). For drying experiments, convective and microwave vacuum drier were used. Cranberry samples were rehydrated in water at +20±1 °C and +40±1 °C. The moisture content of the cranberry samples after rehydration was estimated as oven-dry method. The rehydration properties of cranberries increased with the increase in temperature, up to +40±1 °C, the increase being more significant at the initial stages of the process. Microwave drying possibly produces a sample with increased porosity, which in turn leads to improved rehydration characteristics and a softer product and may reduce processing time. Pre-treatment of berries did not significantly influence the increasing intensity of moisture content during rehydration, but the drying methods within rehydration at the temperature of +40±1 °C significantly influenced the increasing intensity of moisture content.
显示更多 [+] 显示较少 [-]Preliminary results of 1-methylcyclopropene influence on apple quality during storage
2012
Juhnevica, K., Latvian State Inst. of Fruit-Growing, Dobele (Latvia);Latvia Univ. of Agriculture, Jelgava (Latvia) | Skudra, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Skrivele, M., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Seglina, D., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Skudra, G., Latvia Univ. of Agriculture, Jelgava (Latvia)
Apples are the most popular and common fruits in Latvia. Storage technology is crucial to preserve fruit quality as long as possible. Choosing the appropriate gas content of the storage environment can prolong storage life two to three times for apples. The aim of the research was to compare six different type of apple grown in Latvia, which was stored in diverse conditions. All experiments were performed at Latvia State Institute of Fruit-Growing through 2011 – 2012. For fruits before storage, 1-methylcyclopropene (1-MCP), which blocks the emission of ethylene, was used. Apples were stored in a cooler and in ULO type plastic bags in a modified environment with two different gas contents. The temperature of the environment was +2 ±1 °C with 90% relative humidity. Changes in physicochemical (soluble solids, total acids and flesh density) indexes were examined before and during the storage. The results showed 1-MCP has a positive effect on quality preservation of fruit. Fruits stored in ULO type plastic bags (gas content: 1.5% O2 and 2.5% CO2) had the best results in preservation of physico-chemical indexes. Examination of results revealed that physico-chemical indexes changed the most in samples stored in the cooler.
显示更多 [+] 显示较少 [-]Sensory properties and chemical composition of cider depending on apple variety
2012
Riekstina-Dolge, R., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Apple variety influence chemical composition and sensory properties of products obtained from apples. This paper reports the influence of apple varieties on the sensory properties of the cider evaluated by two differently trained panel groups. Juices of five varieties apples (‘Auksis’, ‘Lietuvas Pepins’, ‘DI-93-4-14’, ‘Remo’ and ‘Kerr’) were fermented with Saccharomyces bayanis EC-1118 (Lalvin, Canada). The sensory evaluation of samples was carried out with two panel groups – experts (experienced in the field of beverage technology and evaluation) and trained panellists (finished basic course of sensory evaluation). Experts identified flavours of cider, and evaluated intensity of sensory properties, namely, clarity, aroma (apple, fruit, yeast), taste (apple, yeast, sour, astringent, bitter) using line scale. Trained panellists evaluated the samples only using line scale. Four descriptors were significant for characterization of differences in ciders from various variety apples, namely, sour taste, apple taste, apple aroma and clarity. The research suggests that, varieties with more intense apple and fruit aroma, apple taste and additionally with astringent and bitter taste notes are preferable. Taking into account these results, higher evaluations for cider ‘DI-93-4-14’ were observed, followed by ‘Remo’ and ‘Kerr’.
显示更多 [+] 显示较少 [-]Root vegetables from Latvia: quantitative analysis of trace elements
2012
Vincevica-Gaile, Z., University of Latvia, Riga (Latvia) | Klavins, M., University of Latvia, Riga (Latvia)
Food and drinking water are the main sources of trace and major elements. Besides the elements that are vitally essential for living organisms and human health, food may contain the traces of potentially toxic elements. Environmental site specific impact is one of the influencing factors of elemental content in plants that is important issue also for quality of food crops. Quantitative content of several trace elements (e.g., Al, As, Cd, Co, Cr, Cu, Ni, Pb, Zn) detected in food crops reveal environmental background levels as well as it can be associated with unexpected food contamination. Current study involves quantitative analysis of more than 200 root vegetable samples (onions, carrots and potatoes) grown and collected in Latvia in the harvesting season of 2010. Within this study the quantitative analysis of vegetables for 9 elements (As, Cd, Co, Cr, Cu, Ni, Pb, Se, Zn) was performed. After the wet digestion of samples, the quantitative analysis was done by using inductively coupled plasma mass spectrometry (ICP-MS). Obtained results revealed wide ranges of trace elements in root vegetables, including potentially toxic elements. Comparison of element content in edible parts of vegetables and potato peel showed that a great part of elements (e.g., As, Co, Cr, Pb) is concentrated in peel; however, some elements (e.g., Cd, Se, Zn) are taken up by plants, and therefore may contaminate food more easily. Element transfer routes and their biochemistry is a complicated issue that is affected by natural environmental factors as well as by anthropogenic activities.
显示更多 [+] 显示较少 [-]Rheological properties of triticale (Triticosecale wittmack) flour blends dough
2012
Sabovics, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
Triticale is an amphidiploid hybrid between wheat and rye having protein-rich grain. For expanding the range of bakery and pastry production in the world there are being developed various recipes for product enriching with fibre, especially b-glucan, proteins, vitamins and other nutrients for a healthier diet. It can be done making a flour blend from whole grain triticale, rye, hull-less barley, rice and maize flour. The aim of research was to evaluate the rheological properties of dough made from different cereals flour and flour blends. Whole grain flour of triticale, rye, hull-less barley, rice, maize and flour blends were used in this research. Flour blends were made from triticale in a combination with other flour (whole grain rye, hull-less barley flour, rice and maize flour) in various proportions. Wheat flour (Type 405) was used as a control. Rheological properties of mixed flour dough were studied using Farinograph (Brabender Farinograph-AT, GmbH and Co. KG, Germany). Moisture content of flour and flour blends was determined using AACC method 44-15A. Water absorption and dough development time decrease, but dough stability, time of breakdown and farinograph quality number increases, increasing proportion of other flour in triticale flour. The flour blends need less time for dough development comparing with triticale flour. Enriching triticale flour with whole grain rye, whole grain barley, rice and maize flour in various proportions made triticale flour dough more rheologically stable during mixing.
显示更多 [+] 显示较少 [-]Consumers’ attitude towards availability and quality of gluten-free products in the Latvian market
2012
Ozola, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
Celiac disease is an autoimmune enteropathy disease, triggered in genetically susceptible individuals by ingested gluten from wheat (Triticum), rye (Secale cereale), barley (Hordeum vulgare) and other closely related cereal grains. The only way of the effective daily treatment is a strict gluten-free diet. From the investigation of products available in the local market, it was found that Latvian producers do not offer gluten-free products. The aim of this research was to study a celiac patient’s attitude to gluten-free product quality and availability in the Latvian market and purchasing habits. The survey was designed using website www.visidati.lv, and a questionnaire was sent to people suffering from celiac disease. The respondents were asked to fill in the questionnaire from the beginning of December 2010 till the end of July 2011. The questionnaire was performed with 131 celiac patients, respondents were from all Latvian regions and they answered 15 questions. One of the most important questions was aimed to find out consumers’ opinion about quality of gluten-free products, consumption patterns of gluten-free products, and, moreover, their interest in products made in Latvia. Respondents were asked to name gluten-free products they mainly buy and give specific purchase locations, evaluate the quality of products and necessity for products produced in Latvia. The results of questionnaire show that the consumers are satisfied with the quality of gluten-free flour, flour blends and pasta, but are not satisfied with the quality of bread and confectionery available in the Latvian markets.
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