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Beta-glucan in hydrolysed soluble and insoluble oat fractions
2005
Gramatina, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected] | Kreicbergs, V.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
Oats contain more beta-glucan (2-7%) than other croppers. Beta-glucan is the most essential water-soluble dietary fibre. It lowers cholesterine level in blood as well as stimulates elimination of carcinogens from the body. In order to enlarge possibilities of use of oats in a diet, they can be separated in water-soluble and insoluble fractions. The aim of the present study is to determine the amount of beta-glucan in hydrolysed oat soluble and insoluble fractions. Gelatinized, hydrolysed and steeped oatmeal prior to hydrolyse, which was separated in water-soluble and insoluble fractions, was used in experiments. Not more than 6% of gelatinized (non-hydrolysed) oatmeal dry matter dissolved in water. The outcome of fermentative hydrolysed dry matter of water-soluble oatmeal was 40-52%. The content of beta-glucan in soluble and insoluble oatmeal fraction was determined by using McClearly method. The content of beta-glucan fraction of gelatinized oatmeal decreased for 78% in comparison to the content of beta-glucan in oatmeal used in the experiments. The content of beta-glucan in the soluble fraction of hydrolysed oatmeal decreased for 8.1% to 9.2%, and increased for 35-42% in the insoluble fraction if compared with the content of beta-glucan in oatmeal.
Afficher plus [+] Moins [-]The comparison of chemical pollution between organic and conventional milk
2005
Zagorska, J.(Latvia Univ. of Agriculture, Jelgava (Latvia)) | Ciprovica, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
In Latvia have not been carried out comparable studies regarding chemical pollution in organic and conventional milk, therefore the aim of the present study was to investigate the level of contamination in organic and conventional milk samples by heavy metals and aflatoxin M1. A total of 9 organic bulk milk and 9 conventional bulk milk samples were collected from different regions of Latvia. The content of lead, cadmium, copper, iron, and zinc were detected by flame technique, using atomic absorption spectrophotometer (AAS). The level of aflatoxin M, in organic and conventional milk samples was determined by high-performance liquid chromatography. The means of lead concentration in organic and conventional samples were 0.024 and 0.31 mg kgE-1 wet weight that exceed the permissible level for such a product. The cadmium content in organic and conventional milk samples is very low and fairly constant in all types of milk. The legally accepted upper limits of iron, copper and zinc are not exceeded by any analyzed milk sample, not even from conventional bulk milk. The study including heavy metals and aflatoxin M1 in a range of organic and conventional milk samples found no significant differences between organic and conventional milk (p=0.05) in the level of aflatoxin M1 and the heavy metals.
Afficher plus [+] Moins [-]The effect of some ingredients on stability of butter during the storage time
2005
Vitola, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
The effect of some ingredients on stability of butter during its storage time has been investigated in order to better evaluate the functionality of confectionery. The research established that butter does not contain enough free fatty acids, derived as a result of hydrolysis, to decrease the number of mould and group of Enterobacteriaceae, but they hinder the growth of yeast and aerobic mesophilic and facultative anaerobic microorganisms. The quality of the products can be provided and propagation of microorganisms can be hindered by the comounds that are not traditional preservatives, such as vanilin and glucose syrop. A 10% glucose syrup additive worked as the facilitator of the development of microorganisms because it increased growth of aerobic mesophilic and facultative anaerobic microorganisms, 50% of glucose syrup additive worked as the procrastinator of the development of microorganisms.
Afficher plus [+] Moins [-]Dynamics of peroxide value in flavoured rapeseed oil
2005
Kruma, Z.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected] | Kreicbergs, V.(Latvia Univ. of Agriculture, Jelgava (Latvia)) | Karklina, D.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
Spices are used to season food products. Investigations were carried out to determine dynamics of primary oxidation products in flavoured rapeseed oil depending on used spice, its concetration, storage duration, and sample preparing method. The oil was flavoured with winter savoury Satureja Montana L., hyssop Hyssopus officinalis L., and marjoram Oreganum vulgare L. Results showed that dynamics of peroxide value in flavoured oils were influenced significantly (p is less than 0.05) by all investigated factors - used spice, its concentration, storage duration, sample preparing method, and interaction of these factors, too. Heating of oil in particular cases caused unusual, hard explainable dynamics of peroxide value. It is necessary to investigate optimal conditions of flavouring of oils and components of spices which can influence oxidation of flavoured oils.
Afficher plus [+] Moins [-]The characteristic of birch natural woodland habitats in Latvia
2005
Straupe, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
The role of birch natural (NWH) and potential natural (PNWH) woodland habitats for maintaining of biodiversity in Latvia is described and evaluated. The analysis of the proportion of area of birch stands and natural and potential natural woodland hibitats by regions, by age structure, and by growing conditions has been done. The distribution of birch natural and potential woodland hibitats by habitat groups, as well as most often recognized habitat specialist and indicator species is described.
Afficher plus [+] Moins [-]Study course "Rural tourism" in higher educational establishments
2005
Dunska, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
Rural tourism is becoming more and more important in Latvia and Europe, where rural environment changes, began already more than a couple of decennaries ago. Current trends in development of tourism are favourable for lasting development of rural tourism in the whole European Union. Rural tourim in Latvia extremely popular, because it includes both recreational and cognitive elements of tourism, and takes place in countryside. It gives people a chance to become acquainted witg a country lifestyle, the process of production and be in touch with nature, be able to obtain strength and take emotional pleasure in the energy of nature. The study course "Rural tourism" is lectures both in Latvia's, and foreign higher educational establishments. This course usually is the free choice study object. The aim of the work is to observe study course "Rural tourism" aims and describe the content of this study course in higher educational establishments in Baltic States and North Europe.
Afficher plus [+] Moins [-]Nitrogen, phosphorus and potassium influence on infections by arbuscular mycorrhizal fungi in Dactylis glomerata roots
2005
Druva-Lusite, I.(University of Latvia, Riga (Latvia))E-mail:[email protected] | Liepina, L.(University of Latvia, Riga (Latvia))E-mail:[email protected] | Skujins, J.(University of Latvia, Riga (Latvia)) | Antonijs, A.(Latvia Univ. of Agriculture, Skriveri, Aizkraukle reg. (Latvia). Skriveri Research Centre)
The aim of this research was to compare effects of fertilization with various ratios of N, P and K (N:P:K) on arbuscular mycorrhizal fungi (AMF) infection in roots of Dactylis glomerata in Ca-carbonate (limed) and non-limed meadow plots at the Research Centre of Skriveri, Latvia University of Agriculture. Dactylis glomerata roots were excavated from variously fertilizer plots, a minimum 3 root samples per plot and analysed for two consecutive years. Arbuscular mycorrhizal fungi infection rates were estimated according to accepted scoring tables used for determination of AMF colonization.
Afficher plus [+] Moins [-]Acidifiers additive projection on pigs metabolic processes and digestive tract microflora
2005
Jansons, I.(Latvia Univ. of Agriculture, Sigulda (Latvia). Agency Research Inst. of Biotechnology and Veterinary Medicine Sigra)E-mail:[email protected] | Nudiens, J.(Latvia Univ. of Agriculture, Sigulda (Latvia). Agency Research Inst. of Biotechnology and Veterinary Medicine Sigra)E-mail:[email protected]
A study was conducted to determine efficiency of an organic acids additive on pigs metabolic processes and diggestive tract microflora. The pigs of control group were fed without an organic acids additive. The feed of the trial group piglets contained 6 kg of organic acids additive per tonne feed, for starter pigs - 4 kg per tonne feed, for finished pigs - 3 kg per tonne feed. The study indicated that at the age of 130 days, pig mass in the trial group was 54.08 kg an average, but in the control group - 51.06 kg, which showed that pigs from the trial group had by 6% higher average mass than in the control group (p is less than 0.005). At the age of 160 days, pig mass in the trial group was an average 94.3 kg, in the control group - 90.63 kg; pigs from the trial group had by 4% higher mass than in the control group (p is less than 0.005). Feed consumption for the trial group was by 1% less than in the control group. Average daily gain for the trial group was 0.663 kg, which was by 6% more than for the control group pigs (p is less than 0.005). Feed conversion in the trial group was 3.06 kg, but in the control group - 3.275 kg, i.e. 6.4% higher than in the trial group. Analyses of Jejunum microflora showed that use of acidifier additive reduced Mould colony formed units - CFU amount in 1 g of the trial group sample by 6%. Staphylococcus species amount in the trial group was 500 CFU in 1 g of sample, but in the control group - 40000 CFU, i.e. 80 times more. In the trial group, Lactic acid bacteria CFU amount in 1 g of sample was by 6% higher than in the control group. The results of Rectum microflora analyses showed that Staphylococcus species amount in the trial group was 12000 CFU in 1 g of sample, but in the control group it was by 34% higher.
Afficher plus [+] Moins [-]Insurance of the milking equipment washing regime in lowered environmental temperature
2005
Zujs, V.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected] | Priekulis, J.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected] | Iljins, U.(Latvia Univ. of Agriculture, Jelgava (Latvia)E-mail:[email protected]
In Latvia, use of unheated cow sheds with lowered environmental temperature is growing. In such circumstances, cooling of the milking equipment washing liquid is more rapid and quality of the washing equipment decreases. However, it may be eliminated by coating the milk and washing liquid piping with heat insulation. A mathematical model of the milking equipment washing liquid by which the end temperature of the washing liquid cooling can be determined is developed. Two types of heat insulation materials are under the trial. Laboratory experiments on cooling of the washing liquid are carried out and the experimental coefficients of the mathematical model are determined.
Afficher plus [+] Moins [-]Impact of the working width of the plough body on the tillage efficiency
2005
Rucins, A.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected] | Vilde, A.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
Theoretical and experimental investigations are carried out to estimating the impact of the plough body working width on its specific draft resistance, as well as the ploughing efficiency. By using analytical correlations derived as a result of theoretical research, a computer algorithm has been worked out for simulating the functions of the plough body and the forces exerted by soil upon the operating parts, as well as its draft resistance. Specific draft resistance of the plough body, energy consumption, as well as labour efficiency and ploughing costs depend considerably on the working width of the body. By increasing it, the energy capacity, specific fuel consumption and expenditure decrease, but labour efficiency increases.
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