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Studying of quality parameters of Hungarian and Greek honey samples
147-153Views:255Honey has been a valuable food for mankind since ancient times. It was the only sweetener until the start of industrial sugar mass production. Honey plays an important role in our nutrition and its positive effects on health are well-known. The quality of Hungarian honey is perfect, so it is very important to safeguard and monitor its quality continuously and to build up a good traceability and quality assurance system. For such a system, it is necessary to study the nutritional properties and the origin of different honey samples. In our study, we study Hungarian and Greek honey.
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Comparison of the alveographic qualification and the baking quality of winter wheat
294-302Views:200On the basis of the operative French regulations, we qualified the alveographic qualification and the valorigraphic qualification respectively for each of the 10-14 winter wheat varieties grown each year between 2002-2005, and used in a field experiment at the Karcag Research Institute of the University of Debrecen. The field experiment at the Látókép Research Institute of the University of Debrecen allowed us to examine the alveographic and valorigraphic values of the samples of GK Öthalom and Fatima 2 winter wheat varieties taken from an 8 year period (1997-1999 and 2001-2005).
Throughout the experiments on samples from the Karcag Research Institute and Látókép Research Institute of the University of Debrecen, we tried to find whether the alveographic W value or the P/L value provides the safer method for the qualification of wheat samples, instead of the qualification commonly used in Hungary. We found that in terms of the samples from the Karcag Research Institute, the baking quality and the W value in each of the examined years, while in terms of the Látókép Research Institute, most of the years showed a close positive correlation, contrary to the close negative relationship between the baking quality and the P/L value. The correlation index varied depending on the year, the variety, and fertilizer doses, which require further examinations. -
A tárolási feltételek hatása a kukorica Fusarium fertőzöttségére és toxin szennyezettségére
28-32Views:289Corn samples harvested in 1997, 1998 and 1999 from different soil types were stored at different conditions (temperature, moisture content, state of kernels) for six months. The Fusarium contamination was examined by plate dilution method and the amount of mycotoxins (F-2, T-2, HT-2, DON, DAS) were determined applying HPLC method immediately after harvesting and in the third and sixth month of storage. The aim of our study was to find correlation between the ecological factors, storage conditions and the examined parameters mentioned above, as well as to prove them statistically. According to the examinations carried out after harvesting we could state that the soil type had no effect on the parameters. Analysing the effect of the years we found considerable differences. The Fusarium infection of corn samples in 1998, while the toxin contamination in 1999 was the highest. The results of storage experiment show that year (number of microscopic fungi, F-2, T-2, HT-2, DAS and total toxin content) and moisture content of kernels (F-2, T-2, and total toxin content) have a significant effect on the examined parameters. We could prove the effect of temperature on the T-2 content (samples with natural moisture content) and DON content (samples with 14% moisture content). Higher values were found at higher temperature storage. The ratio of damaged kernels influenced the DON concentration in the non- wetted samples and the number of microscopic fungi in the wetted samples.
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Application of the SDS-PAGE method for the characterisation of winter wheat flour quality
112-118Views:134The principle, development and importance of the SDS-PAGE method are presented in this article. The SDS-PAGE method has become one of the basic methods of molecular biological research, because it is widely applicable and its sensitivity is excellent in the separation of wheat storage proteins.
We have shown the application of this method with a concrete example. It was also tested whether, it was possible to obtain a better baking quality product from a large amount of poor quality less valuable wheat by fractioning the flour according to particle sizes after grinding. We studied the rheological properties of flours with different particle size fractions from the original flour. The baking quality of the original flour was B2. The 125-90 and 90-63 μm fractions have significantly better baking quality (B1) than the original flour. The protein contents of these flour fractions were also significantly higher than the protein content of the original flour. We had a question: what has influenced the baking quality: the protein content or other factors? We searched for an explanation on these results in the protein composition of the flour samples. We studied the distribution of glutenin-fractions by SDS-PAGE method and evaluated them. We found with correlation analysis that the amount of LMW-Glutenin D-group (52-60 kDa) is in a strong, negative correlation to the baking quality (r = – 0.855*). Therefore, the baking quality of flour samples was influenced by this glutenin fraction. -
Comparison of alveohraph and extensigraph properties of winter wheat samples
27-30Views:148The rheological properties of dough are determined by the amount and proportion of gliadin and glutenin proteins. Extensibility and resistance to the extension of doughs which can be measured using the extensigraph or alveograph allow good assesment of the baking behavior under realistic conditions. In our study, we compared the extensigraph and alveograph parameters of 87 flour samples. The results showed that the alveograph parameters were different from the extensigraph parameters. The classification of wheat varieties was different, and the order of varieties, as well. The alveograph properties were affected by other factors than the extensigraph properties, except the W value. The two rheological tests did not give similar results, therefor neither test are replaceable.
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Utility of Winter Wheat According to Visual and Microbiological Fusarium Infection, as Well as Toxin Examination
26-34Views:105In 1998 the Fusarium infection was studied visually and microbiologically and also F-2, T-2, HT-2, DAS and DON contamination were measured using 22 winter wheat samples. The correlation between the different parameters of 22 wheat samples were determined by regression analysis. According to our results we can state the following.
There is no significant connection between the results of visual, microbiological and toxicological examinations. This means that no certain conclusion can be drawn about the toxin contamination of samples – which is a determining factor of its utility – based on the visual symptoms and the plate dilution method.
Our results indicate however – though it is not proven statistically – that those samples in which the Fusarium infection did not exceed the limit of the standard, also had low toxin contamination, therefore they can be used as components of forage.
It is a considerable problem, however, that according to the visual qualification, such samples are excluded from the later utilisation, wherein the toxin contamination does not justify such action. Therefore, it is necessary to examine the toxin content of those samples which show high infection by visual symptoms. To reducing the number of expensive toxin examinations it would be advisable to change the currently used 0,5% limit which is indicated in the standard for a higher value of infection, for example to 2%, as recommended by Mesterházy (1998).