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  • Changes of Quality of Winter Wheat During Maturing
    105-112
    Views:
    84

    We analysed the flour of two winter wheat varieties to determine the effect of maturity state and grain position in the ear on the element composition of flour. Samples were taken from the 14th to the 42th day of anthesis. Ear samples were cut into three (basal, central and apical) parts, the trashed grains were milled, and the element compositions of the flours were determined.
    We found that the grain position within the ear has an effect on flour element content. Flours of apical grains had lower nitrogen, phosphorus and sulphur contents than flours of central and basal grains. The nutrients can be divided into two parts, based on the formation of element content during maturation. Nitrogen, sulphur and copper contents changed continuously during maturity, while the P, K, Ca, Mg, Mn, Sr and Zn contents decreased until a specific value and became nearly constant in the second half of maturity. We found that – although the nitrogen concentration of flours changed continuously – the amount of nitrogen in the flours reached a constant value for the second half of maturity.

  • Investigation of the production parameters, nutrient and mineral composition of mealworm (Tenebrio molitor) larvae grown on different substrates
    129-133
    Views:
    190

    During the rearing of mealworm (Tenebrio molitor) larvae, the optimisation of the growing substrate has a particular importance. The application of the appropriate substrate is a fundamental pillar for intensive and safe production. The requirements for substrate include the lack of toxins, high nutrient and micro-macro element content. The aim of this study was the evaluation of the effects of different substrates on the production parameters, nutrient and mineral composition of the mealworm larvae. The experiment lasted through 14 days. 5 treatments were set up at, where the variable was the substrate. The test system consisted of 25 units (5 treatments and 5 replicates). 10 mealworm larvae per unit, (total of 250 larvae) were used at the beginning of the experiment. Regarding the substrates, our study included sweet potato (SP), may turnip tuber (MT) and may turnip leaf (ML). In addition to the plant by-products, wheat flour (WF) and wheat semolina (WS) were used as control substrates. Trace element uptake and production parameters of the larvae were determined at the end of the experiment. Regarding the production parameters, it can be stated that the wheat semolina (0.081 ± 0.005 g) and wheat flour (0.069 ± 0.007 g) substrate used as control gave the best results for the final body weight. In terms of plant raw materials and by-products, sweet potatoes (0.063 ± 0.007) can only be recommended as substrate, while may turnip tuber and may turnip leaf produced significantly lower final body weight results (MT=0.034 ± 0.002 g ; ML= 0.036 ± 0.002 g). The nutrient composition of the larvae was not affected by the substrate, these results confirmed the high protein and fat content reported in the literature. The results with the production parameters were contradicted by the micronutrient content. Larvae reared on may turnip leaf (ML) and tuber (MT) showed the highest values for most of the macro- and microelements (potassium, calcium, magnesium, iron, zinc, copper) tested.

  • Relation of availability and barley uptake of some potentially toxic elements
    7-10
    Views:
    70

    A small-plot microelement load field trial was set up on brown forest clay soil with eight elements (Al, As, Cd, Cr, Cu, Hg, Pb, Zn), on 3 levels each (0/30, 90, 270 kg element ha-1). The soil was treated with soluble salts of elements once at initiation (1994). In the seventh year of the experiment (2001) winter barley was the test plant. The total element content was determined in plant samples (shoot, straw, grain) after microwave digestion using cc.HNO3+cc.H2O2. The element composition of the prepared samples was determined using ICP-MS technique. In the experiment toxic effects of treatments and yield loss could not be observed. Zn and As contents in barely shoots were only moderately increased by increasing microelement loads. Effects of Cr, Cu, Hg, Pb and Al treatments could not be observed. On the other hand, Cd accumulation was significant in the shoot. Cd content was also increased both in straw and grain. Results of this experiment prove that Cd remains mobile in the soil-plant system for a long time. Its accumulation can be observed both in vegetative and reproductive parts of plants without toxic symptoms and yield loss.

  • Element content analyses in the Institute for Food Sciences, Quality Assurance and Microbiology
    203-207
    Views:
    111

    The role of chemical elements to ensure and promote our health is undisputed. Some of them are essential for plants, animals and human, others can cause diseases. The major source of mineral constituents is food, drinking water has a minor contribution to it, so the knowledge of elemental intake through food is crucial and needs continuous monitoring and by this way it promotes the food quality assurance and dietetics.
    With the evolution of spectroscopic methods increasingly lower concentrations could be determined, so the elemental composition of a sample could be more precisely and fully described. Due to the results the gathered knowledge up to the present is supported and new observations can be done helping us to understand such complex systems as biological organisms are.
    The quality of a food is determined by the full process of its production, consequently it starts with agricultural production so elemental-analysis usually cover the whole soil – plant – (animal) – food chain, by this way the „Fork-to-Farm” precept is true in elemental analysis field also.
    The history of elemental analysis in the University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Food Processing, Quality Assurance and Microbiology goes back to 1980s when the so called Regional Measurement Central gave the background for research. The continuous deployment resulted in an obtain of an inductively coupled plasma atomic emission spectrometer (ICP-AES) in 1988, which extended the scope of examinations due to its excellent performance characteristics
    compared to flame atom absorption (FAAS) and flame emission spectrometers (FES). The instrumental park retain up to date correlate to the developing analytical techniques due to acquiring a newer ICPAES in 1998 and an inductively coupled plasma mass spectrometer in 2004 – which sensitivity is three order of magnitude better compared to ICP-AES. The Institute supports the work with its own ICP-AES and ICP-MS since 2011. 

  • Element Content of Herbaceous Plants in the Floodplain Meadows
    55-58
    Views:
    93

    Animals require well-balanced nutrition. The elemental content of the vegetation of meadows is influenced by as many factors such as heat, rainfall, irrigation, soil type and nutrients, meadow types, species, aspects of the vegetation period and cultivation.
    Natural meadows used extensively are common sights on river floodplains. Since chemicals are banned and the species number is high, measuring the elemental composition of plants on these meadows is beneficial. Cenological survey and element content measurements were held on the rich flora of four natural meadows in the year 2001.
    Weeds, in a wider sense, are plants not directly involved in growing, although their nutritional values make them important costituents of feed. Meadows are enriched by their relatively high microelement content.
    On the sampling sites, the ratio deviated from the ideal 2/3 parts monocotyledon and 1/3 part dicotyledon, but this did not mean a Mn deficiency as it would have been assumed.

  • The effects of the nanoselenium supplementation to the production parameters and the selenium retention of the red drum (Sciaenops ocellatus)
    43-48
    Views:
    196

    The selenium is an essential trace element with antioxidant effect, constituent of many enzymes, natural component of the body of the animals. The addition to the fish feed as micro element supplementation is generally accepted. Numerous animal experiments veryfied, that the antioxidant effect of the nanoselenium is higher than other selenium forms. But no much information is available of the usuage at fish.

    In the experiment were investigated the effects of the nanoselenium supplementation of a commercial fish feed were investigated to the production parameters and the body tissue composition. The correlation between the accumulated selenium content of the body and the treatment, and the feed conversation was also statistically analyzed beside the production parameters. Furthermore we were curious, if can be toxic the nanoselenium in higher doses.

    The experimental stock was placed into 12 plastic tanks (each 70 l water vol.) in a recirculation system for larval rearing. The salinity and the water temperature was constant during the 8 week long experiment. The feeding was ad libitum, 4 times a day. Beside the control five (1, 1.5, 2.5, 5.5, 10.5 mg Se kg-1) duplicated treatment were set.

    According to the results, from the production parameters only at the value of FCR and the survival was found significant difference (p<0.05) between the groups. However strong correlation (r=0.752–0.780, p<0.01) was determined between the treatment and the accumulated selenium levels. To analyzed the free fatty acid contentof the fish, we realized, that the selenium uptake significanly enhanced this level at all treatments. The greatest change was found in case of the type n-3 fatty acids.

    Established by the results, the higher intake than 0.5 mg Se kg-1 was not changed significantly the production parameters, nevertheless to increase the selenium content of commercial feeds to 1.5 mg Se kg-1 could be rewarding on the rearing of red drum.

  • Response of sugar beet to different foliar fertilizers
    127-136
    Views:
    93

    The yield and quality of the sugar beet are mainly determined by level crop production system; therefore the effects of foliar fertilization were studied. Our field trials were carried out in 2005  and 2006 in Hajdúböszörmény, at two experimental sites. In our trials the effects of Biomit Plussz, Fitohorm and Kelcare Cu (having high Cu content) as foliar fertilizers, as well as a fungicide with high sulphur content, Cosavet DF, were studied and
    compared. Effects of treatments were studied in four replicates. 
    We took root samples at 4 week intervals, starting in August. The quality of root (sucrose, potassium, sodium and alfa-amino N content) was determined from filtrated beet broth, by an automatic beet laboratory system, called VENEMA. Leaf samples were taken three times in the growing season, element composition was measured by ICP-OES.
    We found that the crop and the sugar yield were significantly influenced by the foliar treatments both of the two years.

  • Macro element contents of different genotype cows’ milk
    27-31
    Views:
    104

    The level of mineral elements is important factor regarding the quality of milk. The aim of our research study was to determine the content of mineral elements in milk of Holstein, Jersey, Brown Swiss, Ayrshire, Norwegian-red, Swedish-red cows in the first stage of lactation. All cows were fed with the same type (composition) of feed and they were kept under the same condition. The concentration of macroelements (K, Na, Ca, P, Mg, S) in digested milk samples was determined by inductively coupled plasma optical emission spectrometry (ICP-OES).