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’.

Carrots (Daucus carota L.) are a globally important vegetable crop providing a source of important nutritional compounds through their carotenoid content whilst adding flavour and texture to many diets across the world. The current research focuses on the evaluation of sugars, vitamin C and dietary fibre content in ‘Nante’ hybrid carrots. The research was accomplished on fresh in Latvia cultivated carrots harvested in Zemgale region in the first part of October 2011 and immediately used for experiments. Late-bearing hybrids of ‘Nante’ carrots were used for analysis: Nante/ Berlikum, Nante/Maestro, Nante/Forto, Nante/Bolero, and Nante/Champion. The major sugars (fructose, glucose and sucrose) were determined by applying the method of high performance liquid chromatography, vitamin C - by titration with 0.05 M iodine solution, and dietary fibre - using standard method No 985.29. In the present experiments it was found that there are significant differences in the sugar, vitamin C and dietary fibre content between different carrot hybrids. The highest content of total sugars was found in Nante/Maestro and Nante/Champion 7.99 g 100 gE-1 and 7.57 g 100 gE-1 hybrids in fresh weight, respectively. The lowest total sugars content was in Nante/Berlikum hybrid − 4.03 g 100 gE-1. Vitamin C content in carrot hybrid Nante/Maestro was the highest 17.61±0.17 mg 100 gE-1, but in hybrid Nante/Champion - the lowest 8.39±0.17 mg 100 gE-1 of fresh weight. The dietary fibre content in analysed carrot samples ranged from 34.25±0.47 g 100 gE-1 in Nante/Maestro to 25.78±1.54 g 100 gE-1 in Nante/Champion hybrids.

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.

Barley (Hordeum vulgare L.) grain is the main raw material in brewing industry, because beer taste and production process depend on barley grain qualitative indices. One of the barley grain’s qualitative indices is grain sprouting activity. There have been numerous researches that showed the effects of selenium (Se) on hull-less barley sprouting activity and positive influence on biologically active substances and high vitamins concentration in grain (Dūma et al., 2002), but hull-less barley is not widely used. The aim of this study was to explore the influence of different selenium concentrations on the barley grains sprouting activity and content of total phenols. Barley with grain viability of 92% have been soaked in diverse solutions (Se concentration 0.5 mg LE-1 – 10 mg LE-1) for 12 hours, then the grain sprouted at the temperature of +18±2 °C for 5 days and dried in the oven for 48 hours at a temperature of +50 °C. After sprouting, the sprouting activity of the grain was determined, but total phenols amount was determined after grain desiccation. The obtained results showed that the increase in selenium concentration in a solution increased barley grain sprouting activity from 16.3% (0.5 mg LE-1) to 27.9% (10 mg LE-1), but the amount of total phenols decreased.

The quality and nutritional value of milk and dairy products are considerably influenced by the stability of its constituents. The aim of the present study was to evaluate the possibility of enhancing oxidative stability of cow’s milk fat and vitamin B2 using carrots and palm oil feed supplement CAF 100 as sources of natural antioxidants in cow feed. Milk samples were collected after 25-day period of feed supplementation. The intensity of riboflavin losses during its photo oxidative degradation in sunlight was measured by the fluorometric method. A slight and significant (p is less than 0.05) difference in higher vitamin B2 stability was seen in carrot-supplemented group (TG1) milk, where the losses of vitamin B2 were by 3.01% less compared to CG (CG). The oxidative stability of butter oil samples stored in 60 °C temperature was analyzed by peroxide value (PV) method. The oxidative stability of samples initially affected by light from both trial groups was significantly (p is less than 0.05) higher compared to CG showing the good potential of the cow diet enrichment with carotenoid additives. The longest induction period (larger than 14 days) was observed in CAF-100- supplemented (TG2) cow milk fats, which can be explained by carotenoids and tocopherol presence and its possible synergism in fat protection. The induction periods of the TG1 and CG were 12.03 and 10.97 days, respectively.

The objective of the present study was to investigate the microbiological content of cows’ milk in Latvia’s organic farms with a purpose to detect potential microbiological threats in milk. Samples were collected in December 2011 at 12 biological dairy farms of Latvia. Raw milk samples (N=155) obtained from cow composite milk were studied. The total mesophilic aerobic and facultative anaerobic microorganisms (MAFAM), the presence of coliforms and coagulase-positive staphylococci, count of yeasts and moulds were analysed using standard methods. Of the sampled cows 50% had a low somatic cell count (SCC) (LESS THAN 200,000 cells mLE-1), 23% - high, but 27% had a very high SCC (greater than 500,000 cells mLE-1). The mean value of MAFAM in the samples with low, high and very high SCC was 4.7, 5.0 and 5.0 log10 colony forming units (cfu) mLE-1, respectively. The yeasts were present in 57% of milk samples with the mean concentration of 3.1 log10 cfu mLE-1. Moulds were found in 27% of all milk samples; their mean concentration was 4.4 log10 cfu mLE-1. Identified mould strains belonged to genera Absidia, Aspergillus, Geotrichum, Mucor and Penicillium. In cases of subclinical mastitis and latent mammary infection the most distributed mastitis pathogens were Staphylococcus aureus, Micrococcus kristinae, Bacillus cereus and coagulase negative staphylococci.

Nowadays all engineering technologies are based on the automation, but still there are some processes that are not easy to automate. One of them is the heating process using solid fuel boilers. The paper deals with automated double-link air flow control of the combustion process. The research target was to find more effective solutions of furnace air flow regulation to improve the combustion process efficiency. The research object was a 56 kW wood briquettes water heating boiler. The results of the experiment research show a higher efficiency of the combustion process with double-link air flow PI control using motor valves.

The aim of the study was to investigate the properties of hyperspectral reflectance data of Scots pine (Pinus Sylvestris L.) and Norway spruce (Picea Abies L.). The hyperspectral reflectance data was obtained under laboratory conditions from the last season’s needles of healthy 20 year-old trees from the same site. Hyperspectral data was acquired using Themis Vision Systems LLC VNIR 400H portable scanning hyperspectral imaging camera in 400-1000 nm range. Methods of analysis of variance, discriminant analysis and principal component analysis were applied for the hyperspectral data analysis. Differences between Scots pine and Norway spruce reflection data were examined. The most informative spectral range for Norway spruce – Scots pine spectral separation was determined at 666.5 nm – 668.4 nm, most informative waveband - 667.1 nm. Reflectance variations among individual trees of the same species as well as differences in spectral response between needles from northern – southern crown exposition were tested. A significant variation in spectral response of needles of Norway spruce was detected across the whole measured spectral range (955 wavebands) for each sample tree. However, significant variation of spectral response of needles of Scots pine was detected only in 356 out of 955 wavebands for each sample tree. Depending on the crown exposition to the North or South, the reflectance of Scots pine needles differed significantly in 900 spectral bands. No significant differences were detected in 833 wavebands for Norway spruce.

The article focuses on vegetation diversity in the black alder Alnus glutinosa (L.) Gaertn. woodland key habitats in Zemgale, Latvia. Together nine sample plots were established on these habitat types, where next stand South – South West (S-SW) side at the age 1-10; 20-30 and 40-50 years. The vegetation survey has been made in vegetation period of 2010 and 2011. Braun – Blanque method has been used to estimate the projective coverage (%) of tree layer (E3), shrub layer (E2), herb layer (E1) and moss layer (E0) in order to assess the edge effect impact on vegetation diversity according to different ages classes in a next stands of sample plots. The analysis of edge effect verifies that there is a significant influence from the edge in 1st and 3rd zones of sample plots, which lies at S-SW side at the ages 1-10 and 20-30. In sample plots several indicator species of black alder woodland key habitats have been found: Vaccinium myrtillus L., Lycopus europaeus L., Iris pseudacorus L., Comarum palustre L., Plagiomnium ellipticum (Brid.)T.kop. Ordination confirmed that composition of species are relatively close, which demonstrate that species are able to live in similar type growing conditions. Protective species Circaea lutetiana L. and Plagiothecium undulatum (Hedw.) B., S. et G were found on the study sites. Also, adventive species Impatiens parviflora DC was found. Comparing the analysis by zones and sample plots and different age classes, the impact on edge effect has been distinguished in black alder woodland key habitats.

The interest in stumps has increased with recent boost of the bioenergy in Europe. Fuel yield from stumps can be as high as from harvesting residues. The most valuable areas for stump extraction are spruce and pine stands on dry mineral soils. In Finland the utilization of stumps for energy is rapidly moving from the testing phase to forest practice. In 2005 the use of stump wood chips by heating and power plants totalled 0.4 mill. m**3, tripled the consumption of 2004, which corresponds to 14% of the total consumption of forest chips in Finland. Extensive whole-tree harvesting trials in Sweden demonstrate that removal of stumps and slash from clear-felled sites has a strong positive impact on natural forest regeneration. Results from Finland indicate that stump and slash removal can improve productivity and quality of subsequent re-planting of harvested forest sites. The majority of available studies on root rot control demonstrate that subsequent forest regeneration is more successful on sites where the stumps have been removed. The scope of this study was to evaluate quality of forest regeneration after stump extraction in Finland according to the national regulations in Latvia. Number, size, distribution and mortality of seedlings were estimated in 15 compartments. Additionally, moisture and compaction of soils were determined. Results of the study approved that regeneration of forest stands on fertile mineral soils after stump extraction was successful and combination of mounding with scarification during stump extraction provides sufficient growing conditions for new seedlings.