The dietary fibre is edible parts of plants' carbohydrates that are resistant to digestion in human small intestine. Diets naturally rich in dietary fibre support to prevent constipation, improve gastrointestinal health, glucose tolerance and the insulin response, and reduce the risk of colon cancer, hyperlipidemia, hypertension and other coronary heart disease risk factors. About 45% of the dietary fibre intake comes from grains and grain mixtures. In Latvia, there are neither data, nor investigations of the dietary fibre content in grain products during processing and in the end products in which manufacturers and consumers are interested. The aim of this paper was an approval of dietary fibre determination methodology by using analytical equipment the Full option science system (FOS) Analytical Fibertec E 1023. The dietary fibre determination experiments were carried out in the Research Laboratory of the Department of Food Technology at the Latvia University of Agriculture in 2009. The Total Dietary Fibre (TDF) content was analyzed in the samples of rye whole grain flour, rye whole grain bread, and wheat biscuit. Experiments showed that the fibre content in rye whole grain flour is 13.8 g 100 gE-1, in rye whole grain bread - 11.6 g 100 gE-1, and in the wheat biscuit - 1.9 g 100 gE-1. Reached data are comparable with results of other researchers' data.

Bioethanol can be used for food production and to partially replace fossil fuel. Bioethanol is mainly produced from renewable biomass that contains sugars, starch or lignocellulose. The main raw materials for production of bioethanol are cereals, maize (Zea mays), sugarbeets (Beta vulgaris sacccharifera) and other plant species. During the trial that took place in State Stende Cereals Breeding Institute during a three year period (from 2009/2010 to 2011/2012) we examined the suitability of grain from winter wheat (Triticum aestivum L.), triticale (×Triticosecale Wittm) and rye (Secale cereale L.) for the production of bioethanol. Three varieties of each species were used in the trial. During the trial period the grain yield, the ethanol outcome (L tE-1) and the ethanol yield (L haE-1) were determined. It was established that during three years wheat and triticale provided the highest starch content (more than 700 g kgE-1) of the grain as well as the highest ethanol outcome (L tE-1). These species provided both high grain yield (more than 9 t haE-1 on average) and the highest ethanol yield (3300 – 4665 L haE-1). The choice of variety was also important as both the grain starch content and the grain yield depend on the genotype of the variety.

The aim of the research was to evaluate the variability of milk yield and composition for goats with different kid suckling periods. The research was carried out in 2011 and 2012 on a farm where goats of Latvian breed were reared. In both years goats kidded in February and March. Each group included 10 animals. In the first group the kids were weaned on the first day of kidding (A1), in the second – on the 30th day (A30) but in the third – on the 60th day (A60) after kidding. The amount of the milk yield was measured in five successive days after the kid weaning. Milk samples were analysed in an accredited milk laboratory. The highest milk yield was obtained from the goats when kids were weaned immediately after the birth, and samples were taken starting with the 6th day of lactation (2.10 + 0.05 kg), but the lowest from the goats with suckling period of 60 days – 1.68 ± 0.03 kg. The average milk fat and protein content of the goats from the group A1 (53.6 ± 0.92 and 41.6 ± 0.66 g kgE-1), was significantly higher than from the groups A30 and A60 (p is less than 0.05). The average variability of milk yield proved to be from 4.9% in the group A1 to 10.5% in the group A30. The lowest fat content variability was observed for goats of the group A1 in both years – 8.9% and 10.7%, but the highest 20.5% in the group A60 in the first year. The highest variability of milk protein content was observed in the group A30 – 14.8%.

The experiment was carried out in the Latvia University of Agriculture. The objectives of this research were to study changes of bean (Phaseolus) protein fractions occurring under the thermal treatment conditions and determine the critical temperature for Maillard reactions in beans. In these reactions lignified protein is made from amino acids and sugars, and it decreases the nutrition value of the food. If lignified protein exceeds 50% of crude protein content in food, then food is considered unsuitable for daily diet. In this experiment beans were milled and then heated at 50 ± 3 °C, 75 ± 3 °C, 100 ± 3 °C, 125 ± 3 °C and 150 ± 3 °C temperature in the drying oven for 20 h. As a control sample non heated beans were used, and they all were kept in a plastic jar at room temperature (20 ± 1 °C). Dry matter, crude protein, starch, sugar and lignified protein content were determined in heated beans and control samples. No significant changes of crude protein content were observed due to thermal treatment. It was from 24.3 ± 0.3 g 100 g-1 of dry matter. Similarly, no significant changes were observed in starch content, as it stayed averagely 47.1 ± 0.2 g 100 g-1 of dry matter. Medium high correlation was observed (0.64) between lignified protein content and sugar content for in different temperature treated beans. Lignified protein showed exponential growth if the samples were heated at a temperature of 100 ± 3 °C and higher, giving exponential change.

The main purpose of the present experiments was to investigate the effect of various hydrogen peroxide (H2O2) concentrations and for various lengths of treatment on the total carotenoid, β–carotene content, colour intensity and microbiological safety on the fresh shredded carrots. Shredded carrots were dipped in 0.5, 1.0 and 1.5% H2 O2 water solution for 30 ± 1s, 60 ± 1s and 90 ± 1s. Negative effect of H2 O2 on β–carotene content and colour parameters of analyzed shredded carrots samples was not detected. In carrots treated with H2 O2 (p = 0.008) for 60 – 90s the total content of carotenoids significantly decreased during treatment compared to untreated carrot samples. There was significant difference (p is less than 0.05) observed between treated and non–treated shredded carrot samples on the total bacteria count. It was possible to reduce significantly (p is less than 0.05) the content of yeasts and mould up to 99.99% by shredded carrots treatment with 1.5% hydrogen peroxide water solution for 30 ± 1s. In the non–processed carrots E.coli was detected; however, it was possible to destroy E.coli by treating carrots with 0.5% H2 O2 water solution for 30 ± 1s. Considering all experimentally obtained results, we have concluded that fresh shredded carrots could be treated in water with the addition of hydrogen peroxide 1.5% for 30 ± 1s to maintain quality.

Fruits and vegetables are a major source of antioxidants. The aim of current research was to study and compare the antiradical activity, the total polyphenol content (TPC) and the total flavonoid content (TFC) in dried carrots (Daucus carota), pumpkins (Cucurbita maxima), leeks (Allium ampeloprasum var. porrum) and black radish (Raphamussativus) using a traditional convective drier and a microwave-vacuum drier. For each vegetable steaming as pre-treatment was used. Vegetables were harvested in Latvia in 2012, gathered when ripe and then dried. Analyses were made in Latvia University of Agriculture, Faculty of Food Technology laboratories. The total polyphenol content was determined by the Folin- Ciocalteu method and the total flavonoid content - using spectrophotometric method. The antiradical activity was analyzed by the 2,2-diphenyl-1-picrilhydrazyl (DPPH) assay. The results of experiments demonstrate that the total amount of polyphenols ranged from 98.97 to 623.70 mg gallic acid equivalent (GAE) 100 gE-1 in dry weight and the total amount of flavonoids ranged from 40.32 to 100.23 mg catechin equivalent (CE) 100 gE-1 in dry weight. The value of DPPH antiradical activity for vegetable samples ranged from 6.10 to 45.14 percents.

Malt is a natural food product produced by germinating cereal grains. Safety of cereal grains and cereal products is a very important area. Experiments were carried out at the Faculty of Food Technology of the Latvia University of Agriculture. The research object was rye malt. The purpose of the research was to investigate and compare the influence of copper and selenium on microbiological indicators of rye malt. Rye grains of 96% viability were soaked and germinated at temperature +6 ± 2 °C for 4 days, using copper(II) sulphate pentahydrate CuS04*5H2 O solutions (Cu concentration 10 mg LE-1, 50 mg LE-1, 100 mg LE-1) and for 3 days using sodium selenate Na2 SeO4 solutions (Se concentration 3 mg LE-1, 5 mg LE-1, 10 mg LE-1) then the soaked grains dried in the oven for 24 hours. The total plate count and yeast colony forming units were determined in rye malt samples. The obtained results showed that the increasing of copper and selenium concentration in solution significantly changes microflora of rye malt comparing with the control sample.

The paper presents data on the water quality in drainage from manure-fertilized areas in a large livestock company (629 conditional livestock) from 2008 to 2012. The scheme of investigation consists of two field variants: manure fertilized and non-fertilized. Researches are carried out in drained areas, where the drainage water is drained away through outlets. The nitrogen rate 170 kg haE-1 is used annually to fertilize fields in spring. The aim of the research was to ascertain the impact of large livestock company fields fertilized annually with manure on the water quality in drainage. For the purpose of chemical investigations, water samples from drainage were taken once per month. Water analyses were carried out by the accredited Chemical Analytical Laboratory of the Water Management Engineering Institute of Aleksandras Stulginskis University according to specified methods. Investigation results have demonstrated that fields fertilized annually with manure raised the contents of Nmin and P2O5 in the soil by 1.5 and 2.2 times respectively in comparison to the non-fertilized ones. The increase in these contents was conditioned by the higher air temperature and the lower rainfall. The seasonality of Ntotal concentrations in drainage water was discovered: higher concentrations were identified in autumn and winter, lower concentrations – in spring and summer. Due to low dissolubility in the soil, low Ptotal concentrations were identified in drainage water. The highest concentrations were identified with the start of drainage operation.

The aim of the present research was to evaluate the affect of genetic and environmental factors on the variability of the goat milk yield, fat and protein content in goat milk in Latvia. Data of 6067 lactation records from 2400 goats of six different breeds were analysed in the period of 2001 to 2010. The highest milk yield (662.7±14.58 kg) was obtained in 2002, the highest fat content (40.7±0.05 g kgE-1) – in 2004, but highest protein content (32.7±0.19 g kgE-1) – in 2008 (p is less than 0.05). Basically there are two goat breeds in Latvia: Latvian goats and Saanen goats. In the research, 3261 Latvian and 2032 Saanen goats in closed lactations were analysed. It was found that Saanen goats gave the highest milk yield (579.3±5.01 kg), but Alpine goats – the highest fat and protein content (respectively 41.7±0.63 and 32.3±0.30 g kgE-1; p is less than 0.05). It was observed that most of all the goats kidded in winter (2379) and spring (3378). The highest milk yield (583.8±7.39 kg) was determined for goats kidded in winter season, but the highest fat content (41.8±0.06) and protein content (32.3±0.03) – for goats kidded in summer season. The average milk yield in the first lactation (1636) was significantly lower than in the third lactation (578.0±8.34; p is less than 0.05) when the goats produced the highest milk yield in the research.

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.