Search
Search Results
-
Risk effects of the spread route of mycotoxins
90-95Views:444In Hungary the mycotoxin is a great problem, because there are many natural toxins in wheat and maize. These cereals can be found on
considerable proportion of the country’s sowing area, and they are deterministic food for the population. The direct human and animal
utilization of the contaminated cereals mean a serious risk in the food chain. In Hungary’s climate the soil is contaminated with pathogen
moulds, particularly Fusarium species, which increase by respective temperature and moisture content in cereals. The Fusarium can
decrease the quality of the wheat in different ways: decrease the germination capability and cause visible discoloration and appearance of
mould, reduces the dry material and nutrient content of the grain. From the toxins produced by the Fusarium genus, the trichotecene (T-2,
HT-2, deoxinivalenol, nivalenol, diacetoxyscxirpenol, Fusarenon-X) and the estrogenic zearalenon (F-2) are the most common in Hungary.
The fumonisins (FB1, FB2, FB3) first identified in 1988, relatively newly discovered, are also important. Major proportion of mycotoxins in a
healthy organization is metabolized by the enzyme system of liver and intestinal bacteria. The toxicity is reduced or even leaves off.
However, more toxic and biologically active compounds can be formed. For the reduction of mycotoxin-contamination several possibilities
are available in the case of storage, processing and feeding. -
The relationship between gluten proteins and baking quality
117-122Views:639Wheat, one of the most important cereals, is grown on the largest area in Hungary. During hydration of storage proteins of wheat – gliadin and glutenin – the gluten complex is evolved. The gliadin is responsible for the extensibility of gluten complex as well as the glutenin for the strength of gluten. The structure, composition and rheological properties of gluten proteins influence significantly the baking quality. The gliadin/glutenin ratio and the quality and structure of glutenin fraction play the most important role in evolving gluten complex. Changes in the steps of breadmaking technology also have effect on the quality of product. Several tests proved that the higher glutenin content increases the strength of dough while the higher gliadin content increases the extensibility of dough and decreases maximum resistance to extension. The monomer gliadins play a great part in plasticity of glutenin polymer. The quality of glutenin fraction significantly influences the evolving gluten complex, because of the spiral structure of glutenin which deforms under stress conditions, then the β-spiral structure resumes their original conformation by releasing from stress.
The final quality of product evolves as a result of complex characteristics of wheat proteins, so detailed knowledge on the roles of different protein compounds is the base of the quality oriented product development. -
Preliminary results of the combined production of duckweed Spirodela polyrhiza and common carp (Cyprinus carpio) in an aquaponic system
83-89Views:353As a result of population growth, increasin amount of food is needed, and agriculture is under an increasing burden to meet these needs. Traditional agriculture is often attacked due to its environmental impact. We must find alternative, environmentally friendly ways to produce more food. Aquaponics is a closed system in which we can produce both fish and plants at the same time. Duckweed species are small, aquatic, floating plants belonging to angiosperms. It can potentially be an alternative protein source, due to its high protein content, good amino acid supply, and rapid growth. Under suitable conditions, it doubles its weight in 2–4 days, and can reach a yield of 30 t ha-1 year-1in dry matter. It forms a carpet on top of the water and can be found in slow-moving or still waters. Since they are resistant to a wide range of nutrient concentrations, they are also suitable for cleaning wastewater (such as eutrophicated lakes, sewage reservoirs, liquid manure storage). Fish feed is the primary nutrient source for aquaponic systems, which usually contains fishmeal. If duckweed can be used as an alternative for fishmeal in the feed, it could improve the sustainability of the aquaponic and aquaculture systems. In this study, the aim was to develop an optimal harvesting protocol for duckweed Spirodela polyrhiza under aquaponic conditions. In a four weeks experiments, four harvesting protocols were set up, a control where only biomass measurements were made, a 25% group where 25% of the biomass at the time of measurement was harvested, and a 50% and a 75% group where at the time of measurement 50% and 75% of the biomass was harvested. Three replicates were used per treatment. We weighed the biomass every week and removed the amount corresponding to the group. Based on the preliminary results, it can be said that more biomass was obtained in the groups with the 25% harvesting protocol and the control group.
-
Tulip bulbs preparation by heat treatment for forced culture in green house
70-72Views:187Tulip can be grown in parks as ornamental plant and cut flowers, or possibly in protected areas for cut flowers during winter and early
spring.
An important condition for the successful cultivation of tulips is the quality of the bulbs that are going to be planted and their
biological preparation.
Under the quality aspect bulbs have to be uniform and large, preferably with circumference greater than 11 cm and must have good
phytosanitarical status.
Preparation of organic bulbs for ensuring the continuation of the differentiation process of germs (floral), is made during the storage.
It is known that the preparation of organic bulbs are made in interaction with environmental factors, among which temperature plays an
important role. At the beginning and throughout the process of biological preparation, temperature is maintained at a higher level then the
temperature must be low until planting.
The temperature level and the duration of treatment varies by followed objective respectively early or late flowering and staggered
flowers production over a longer period of time.