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  • Optimalization of nutrient supply and row space in the growing of annual caraway
    135-138
    Views:
    61

    Concerning the nutrient supply, it was found that the highest crop was produced with the N80K0 treatment (81.38 g m-2). The K application resulted in a decrease in crop yield. The highest crop yield per plant was found in plots with 48 cm row space. The best germination was reached in the plots with 48 cm row space (73%).
    If the level of K was elevated, the essential oil content increased. The maximum essential oil content was reached by treatment N0K80 (2.6284 ml 100 g sza.-1). The composition of essential oil was influenced both by the nutrient supply and by the growing area. Increasing the row space the ratio of d-carvone decreased. The amount of d-carvone was uniquely increased by use of K. The highest carvone level (66.25%) was identified at the N80+70K80 treatment as an average of row spaces.

  • The special questions of nutrition of forest plants
    83-88
    Views:
    52

    Some physiological effects of bacteria containing fertilizer and some wood ash were examined in the experiments. The minimization of the use of chemicals in agriculture has been an ongoing challenge. One option lies in the intenzification of soil life. The release of organic matters by the roots and bacteria play a significant role in the uptake of minerals. The main problem to usilize wood ash in agriculture is its heavy metal contents. The
    solubility of heavy metals is very low, therefore there is no risk to use the wood ash in the agriculture and in the horticulture according to our experiments. The wood ash and biofertilizer contains several micronutrients in an optimum composition for forestry and agricultural plants.

  • Alternative protein sources in the nutrition of farm animals
    21-31
    Views:
    380

    Protein requirement and its demand of farm animals became one of the critical problems in nutrition on a global scale. Protein requirement has been an explicit demand for a long period with soybean meal and animal protein, but recently there are some limitations in relation to their use and the availability of the high quality fishmeal decreases constantly. For this reason there is increased demand for finding new protein sources which could be the alternatives of soybean meal and fishmeal. Alternative protein sources can be divided into seven categories, according to their origin. In different countries, their use depends on the availability in large quantity and at reasonable price.

    There is a long tradition of using legume seeds, as alternatives of soybean. Most of them contain some anti-nutritive compounds, but it can be reduced with systematic selection. Oilseed meals are also generally use in poultry and pig nutrition, but those crude protein content varied, depending on the oil extraction technology. Green fodder and leaf protein was also proposed as alternative protein sources, but their use is limited, in particular because of the market price. The amount of bioethanol and starch industry by-products increases gradually in recent years, therefore those became alternatives of soybean meal, or in much less extend, fishmeal. However, amino acid composition of such by-products are far from optimal for poultry and pig; therefore, in the case of their use amino acid supplementation is necessary. Several novel protein sources are proposed in the last decade, such as algae or insect proteins. Recently, their availability and use is limited, but in the near future those would be alternative protein sources in monogastric animal nutrition.

  • Experiment of quality properties of dehydrated fruits
    7-15
    Views:
    100

    The lyophilization is the joint application of freezing and drying. It is an up-to-date conserving procedure, the point of which is that the humidity existing in the frozen humid material is transferred from the solid state directly into the gaseous state at a temperature below 0 oC under vacuum. Out of the procedures applied nowadays, this is the most tolerant drying process.
    With regard to the high investment and operational costs, freeze drying is applied only for valuable, heat-sensitive materials when the technological aim is to preserve such properties as aroma, taste and colour as well as such components as proteins and vitamins. This procedure is suitable for drying and conserving certain foodstuffs, stimulants, organic chemicals, medicines and similar sensitive and valuable materials.
    In our institute, we have been conducting freeze drying experiments with regional fruits and vegetables since the year 2005. During the first phase, we examined the heat- and material transfer as well as the abstraction of humidity, while during the second phase we analysed the rehydration ability and nutrient content of the freeze-dried materials as compared to those dried with the method of convection. Moreover we have conducted penetration measurements with a portable hardness tester.
    To sum up the results gained so far, we can state that the quality of the lyophilized materials is better than those dried in the traditional way. It originates partly in the fact that the temperature and pressure applied for the freeze drying are smaller and the drying period is far longer than for the convection drying.
    In contrast to convection-dried materials, freeze dried materials set in close to their original water-content, keep their original shape and size after being rehydrated. The reason of it the porous, spongy structure (flexible cell wall) of the lyophilized products which is able to take up moisture quickly. In addition, the lyophilized products can be rehydrated faster than those dried in the traditional way.
    Regarding the results of the chemical analyses, the following conclusion can be drawn: the vacuum freeze drying results a small decrease of nutrient content and nutritive value for the lyophilized products.
    The results of the hardness tests support the statement that the majority of agricultural materials cannot be considered as an ideal flexible body, because during the experiment the flexibility coefficient changed when going from the surface of the material inwards. In addition, the penetration tests also confirm that the surface of the convection-dried vegetables is at least 1.5-3 times harder than that of the freeze-dried products. The reason of it that it takes place during the drying denaturation processes.
    The article summarizes the results of our research work listed above, in accordance with our experiments conducted by using the characteristic fruits (apple, plum) of the Nyírség Region.