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Influence of hydrolysed oats insoluble fraction on dough quality
2006
Gramatina, I. | Kreicbergs, V.
The major wheat flour constituent, which determines the dough quality, is gluten. Oatmeal has higher biological value due to amino acid composition and content if compared to other cereals, but the technological properties of proteins are not as good as the ones of wheat flour. Oat products can be used in bread making although the increased amount of additives shows negative influence on bread texture, elasticity, volume, taste, and flavour. The method is developed for hydrolysed oatmeal separation in soluble and insoluble fractions, thus extending the oatmeal application possibilities. The aim of the current research was the investigation of influence of hydrolysed oats insoluble fraction on wheat dough rheological properties. The obtained results proved that in case hydrolysed oats insoluble fraction additive was used, water adsorption was increased by 63.8%-66.4% and dough stability time was changed from 4.8 to 10.0 min. The negative influence on dough development time and dough softening degree was observed. The farinograpgh quality index was within acceptable limits (less than 120 FU), if the oat additive of 10% and 15% was used. It is possible to obtain dough with better rheological properties if the hydrolysed oats insoluble fraction additive is 15% from flour mass.
Показать больше [+] Меньше [-]Fortified wheat grains with microelement selenium
2006
Duma, M. | Karklina, D.
Selenium (Se) is an essential microelement for human health; it is not synthesized in human body and cannot be substituted by any other element. Many health problems have a link with Se deficiency. People need to obtain all necessary amounts of selenium with food. Cereal products are important components of our diets and can contribute comparatively large part of the total dietary intake of Se. The wheat grains growing in Latvia contain comparatively small amount of selenium - on average 0.04 mg kgE-1. The objective of this study was to investigate the possibilities of fortifying wheat grains with microelement selenium during soaking grains in selenium containing solutions. Wheat grain was soaked in sodium selenite and sodium selenate solutions with selenium concentration from 10 to 200 mg lE-1. Sprouting activity was determined after 24, 72 and 120 hours, the influence of selenium valence in compound was observed. Comparing the influence of Se**+4 and Se**+6, it can be concluded that Se**+4 does not promote sprouting activity of wheat grains position to Se**+6 which increases sprouting activity till selenium concentration 100 mg lE-1. Uptake of selenium in grains was studied by determination of total Se using atomic absorption spectroscopy method. Linear correlation between Se concentrations in applied soaking solutions and Se concentration in grains was observed. The content of total protein did not change significantly - it varied from 13.64% in the control sample to 13.87% in the wheat sample with the highest applied selenium concentration (200 mg lE-1).
Показать больше [+] Меньше [-]Shelf life extension of fresh sea buckthorn berries (Hippophae rhamnoides)
2006
Seglina, D. | Karklina, D. | Dukalska, L.
Sea buckthorn berries are one of the most important sources of vitamins, minerals, organic acids, polyphenols and other biologically active substances in human nutrition. The shelf life of fresh chilled berries does not exceed one week. The venues of research were Fruit and Berry Processing Centre of the Dobele Horticultural Plant Breeding Experimental Station and Packaging Material Testing Laboratory of the Faculty of Food Technology, Latvia University of Agriculture, from August until October 2005. Two most popular sea buckthorn cultivars in Latvia - 'Avgustinka' and 'Prozrachnaja' - were used for the study. Sea buckthorn samples were packed in ready-made PET/adhesive/PP containers supplied by 'Huhtamaki'. Gas mixture with initial composition of 10% of O2, 10% of CO2, 80% of N2 and ambient air as control were used. Containers were sealed on the packaging equipment 'TECNOVAC Pratica'. Packed sea buckthorn samples were stored at +4+-1 deg C temperature for 50 days. The aim of this study was to clarify the effect of the initial concentration of gas mixture in the package made from plastic of high barrier properties on the quality of fresh sea buckthorn berries during storage time. The results showed that shelf life of fresh sea buckthorn berries without any significant quality changes can be extended till 30 days by packaging in containers with high barrier properties and air ambiance.
Показать больше [+] Меньше [-]Application of quantitative risk assessment in catering area
2006
Melngaile, A. | Karklina, D.
Company - oriented risk analyses is the necessary precondition to establish, validate and improve HACCP procedures in catering enterprise. In catering area no microbiological criteria exist for ready-to eat food in both European and Latvian level. The objective of the study was to apply risk assessment approach to evaluate microbiological risks during food preparation processes in school catering establishments. The aim of the author's research was to assess the level of microbiological contamination of food as well as the changes of microbial contamination during technological processing of food to motivate the necessity for controlling of food contamination levels in frame of HACCP procedures. It was concluded that no significant risk in consumption of cooked minced meat food if cooking temperature is adequate and food is stored at correct temperature after cooking. The storage of salads in ambient air temperature causes a significant increase of bacterial contamination due to high initial contamination level that may create a serious risk in case of pathogenic bacteria. On the basis of research it was concluded that microbiological investigation should be a recommended way to test step-by step the performance of technological processes because the hygiene situation is specific to each catering establishment and safety of the end-products may vary considerably. Microbiological testing of food and environmental samples could be a helpful tool for development and validation of HACCP procedures to assess potential risks and to establish critical limits for managing of technological steps in school food service area.
Показать больше [+] Меньше [-]Investigations of grey alder (Alnus incana (L.) moench) biomass
2006
Miezite, O. | Dreimanis, A.
In the time of the decrease of global fossil resources storage wood, pulp has an increasing importance as a heat energy source. In Latvia, grey alder stands occupy 189.9 thousand ha with a total growing stock of 31.1 mil. m**3. So far in most of cases grey alder is estimated as a low value tree species, because tree dimensions do not to allow obtain a significant proportion of timber quality wood. The increasing fuel shortage has caused the need for growing grey alder as a bio energy supply. Grey alder has not been analyzed intensive until now, therefore the aim of the investigation is to estimate the stand productivity and or above ground biomass; that could serve as a background for recommendations to establish grey alder stands for energy-wood production. The grey alder biomass is dependent on wood density, but density - on wood moisture. The average newly felled grey alder wood density in April is 0.76+-0.011 g cmE-3, but absolutely dry wood density for trees felled in October, the average value of absolutely dry wood is 0.46+-0.005 g cmE-3, which is 1% more than in the spring, but these relationships are not significant relative moisture demonstrates water content in newly felled wood. Its average value is 54.7+-0.5% in April and 53.5+-0.05% in October. Empirical formulae are worked out for absolutely dry stem and branch biomass
Показать больше [+] Меньше [-]Variability and genetic determination of Scots pine quantitative traits at the age of 32 years
2006
Jansons, A. | Baumanis, I. | Dreimanis, A. | Gailis, A.
Survival, growth (height, diameter at breast height, stem volume, yield) and quality (thickest branch up to 2 meters of tree height, branchiness, and stem straightness in grades) of phenotypically selected Scots pine plus-tree progenies from different regions in Latvia at the age of 32 years have been analyzed. The material was planted in 4 tests in different forest types (Cladinoso-callunosa, Vacciniosa, Hylocomyosa, and Oxalidosa) in Kalsnava, Eastern part of Latvia. Average number of trees per family varied from 11 to 21 (survival 18-35%). Mean height for Scots pine at the age of 32 years was 14.2 -16.3 m, coefficient of variation -10-17%, diameter at breast height - 13.1-17.7 cm, 24-32%, stem volume 0.1-0.2 m**3, 49-64%, diameter of thickest branch at up to 2 meters of tree height - 1.3-1.7 cm, 23%. To secure ability for detection of significant (alpha=0.05) family differences, average number of trees number per family at evaluation age should be at least 24. Narrow sense individual tree heritability (h**2) was 0.11 for stem volume, 0.09 for diameter at breast height, and 0.07-0.11 for diameter of thickest branch up to two meters of tree height.
Показать больше [+] Меньше [-]Indications of pupils' competitiveness
2006
Kalnina, I. | Katane, I.
The ongoing globalisation and integration processes increasingly influencing the different social processes, including the situation in labour market have raised up the topicality of the necessity in education to develop competitiveness of the society in general as well as in every individual. Several documents of international and national importance provide evidence for such an assumption. Education is to become preconditions, process, result, and tool for the development of competitiveness of an individual. This promotional process should be based on scientific research as well as become a part of the duties of every educator. Therefore it is important to scientifically substantiate the conceptual notion 'competitiveness', differentiating between its structure, components, and features. The authors of the present paper have found the theoretical background: 1) theoretical substantiation of the concept of competitiveness in the researches by scientists from Western countries and Russia; 2) appropriate definitions of the concept 'competence' for research of pupils' competitiveness.
Показать больше [+] Меньше [-]Constraction of the local science lessons in the conservation and reforestation at Nam-Ko drainage basin, Amphoe Lomsak, Changwat Phetchabun
2006
Rangson Pengpad, Phetchabun Rajabhat University, Phetchabun (Thailand) | Tassanee Sriphetphan, Phetchabun Rajabhat University, Phetchabun (Thailand) | Saowanit Daengtongdee, Phetchabun Rajabhat University, Phetchabun (Thailand) | Supot Kerdmee, Phetchabun Rajabhat University, Phetchabun (Thailand) | Sanrudee Deepu, Phetchabun Rajabhat University, Phetchabun (Thailand) | Trinuch Chantarat, Phetchabun Rajabhat University, Phetchabun (Thailand)
Factor relates to the success of community businesess: A case study of Wang Num Kheow chemical-free agriture supporting group Wang Num Kheow subdistricts, Wang Num Kheow district, Nakhon Ratchasima province
2006
Praphan Chaeng-iam, Uttaradit Rajabhat University, Uttaradit (Thailand).
[Study of cattle Husbandry by wisdom knowledge to the rural economic Ban Napau, Tambon Chat Trakan, Phitsanulok province]
2006
Pisan Riwthongchai, Pibulsongkram Rajabhat University, Phitsanulok (Thailand) | Chamnian Dantim | Sunimit Chumphong