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Wine adulteration and its detection based on the rate and the concentration of free amino acids
139-151Views:365Following the definition of wine adulteration, the authors briefly review its history from ancient times to present day and describe the methods that are applied for adulteration of wine from the historical point of view. More space is devoted to the Hungarian wine adulteration and to the detailed reports of the early methods, which attempted to discover fake wine. It describes in detail the current situation of wine adulteration and the fight against counterfeiting. The second half of the review article presents some examples of the analytical chemistry techniques with which fake wines can be detected. In doing so, priority is given to the discussion of high performance liquid chromatography and gas chromatography applications. The end of this paper describes the free amino acid content of wines, and the possibilities of using the results for detection of wine adulteration.
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Investigation of the milk composition of three Tsigai sheep varieties, and the detection of cazein fractions of sheep milk by Reversed-Phase HPLC
13-22Views:108The measurements started in 2005, the author used the milk of 3 types of Tsigai Sheep that are suitable for milking, they examined the milk composition, the possible differences between the milk types, the coagulation characteristics, cheese processing, yielding characteristics and the transfer of solid content into cheese. From the large number of measurements, the results of milk composition examinations are described.
During the research the author examined the milk coagulation property of three types of Tsigai Sheep QTS 25 is a substance investigating instrument, and its primary mission is the analysis of the substance profile. The advantage of this instrument is the representation of the survey graphs from which the part of the substance characteristics could be directly read off. By the help of the applied mathematical and statistical operations we tried to establish connection between the congealment-hardness and the specialty of the different types of Tsigai Sheep.
In 2006 the author began the identification and qualification of the major sheep milk proteins by RP- HPLC method. She used a scientific article written by Bordin et al. The method is able to separate and quantify the seven major proteins. However Bordin’s procedure was developed using bovine milk, the author adapted it to sheep milk. -
Effect of different production types on the yield and ß-carotene content of sweet potato /cultivar Ásotthalmi- 12/
45-49Views:170Production of sweet potato is extending in Hungary, despite the fact that there is no field-specific production technology. Therefore, many growers cannot utilize potential yields and quality. The goal of this study was to determine the optimal production method of the Ásotthalmi 12, a Hungarian sweet potato cultivar which can adapt to the Hungarian climate. The effect of single and twin rows production on the yield of this cultivar was examined. The planting was carried out on June 24th, the harvesting on October 20th and the growing-season was 120 days long. Uniform nutrient supply was applied to the whole field experiment. During basic fertilization, 206 kg Knd 20 kg N, 36 kg P ha-1 were used on the soil. While forming the ridges, we used an additional 25 kg N, 45 kg P and 62.5 kg K ha-1. We adopted drip tape irrigation on the experimental field. After the planting, from the 8th week of the vegetation, another 21 kg ha-1 K, 10 kg ha-1 MgSO4, and 2 kg ha-1 Ca(NO3)2 was added in one dosage weekly, until the 13th week of vegetation. At the evaluation of the experiment, we examined the yield regarding the whole experimental plot. SPAD and fluorescence measurements were carried out on 08.16. 2019, 08.28.2019, and on 09.13.2019, during the watering break. To demonstrate the difference between the dates, we applied ANOVA and Tukey post-hoc tests. For the measurement of phytonutrients HPLC, a liquid chromatograph was used, where the carotenoid content of the Ásotthalmi 12 cultivar was determined in connection with the different production methods. Test results showed that twin rows production leads to a nearly 30% greater yield, than single row production. We determined, that the growth of yield correlates negatively to the ß-carotene content of the Ásotthalmi 12 cultivar sweet potato.
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Búzaminták fungicid szermaradvány ellenőrzése és gombafertőzöttségének kimutatása
45-51Views:88To protect crops with chemicals against different microorganisms are very important because residues of toxins could pollute infected grains. This could have the meaning of serious danger to the human and animal health. Similarly important is knowledge of details about presence or absence of any practically applied protective compounds. Experimental studies were performed on fungicide treated cereals of the Cereal Research Non-Profit Company, Szeged. Chromatographic methods were used (GC and some GC-MS) to find low level fungicide residues, microwave-assisted isolation of ergosterol was followed by HPLC to detect possible fungal infections and a more detailed microbiological analysis completed the work. Concerning the dry year 2000, no fungicides were found in the samples (by November), the ergosterol level was found to be less than 8 ppm, meaning good quality, coupled with an extremely low level of fungal infections. This was confirmed by direct microbiological testing. In comparison with the microbiological results from 1999, a negative difference can be recognized, most probably due to the rainy weather throughout the year.
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The effect of sous-vide cooking on the antioxidant properties of oyster mushroom (Pleurotus ostreatus L.)
177-184Views:167Oyster mushrooms (Pleurotus ostreatus L.) are renowned for their antioxidant, antimicrobial, and prebiotic properties. This study explores the antioxidant characteristics, activity, and β-glucan content in freeze-dried mushroom samples, investigating the influence of sous-vide cooking. Uncooked freeze-dried P. ostreatus and three pre-cooked freeze-dried samples (70, 80, 90 °C through 4 hours) were analysed for Total Polyphenol Content (TPC), Total Flavonoid Content (TFC), Radical Scavenging (DPPH), Ferric Reducing Antioxidant Power (FRAP), and β-glucans content via HPLC and Total Dietary Fiber (TDF) via enzymatic gravimetric method. Results indicate that uncooked mushroom powder exhibited superior antioxidant capabilities compared to cooked samples. The sous-vide cooked (80 °C) mushrooms displayed the highest total phenolic and flavonoid content. Moreover, pre-cooked (70 °C) mushroom powder demonstrated the highest β-glucan content, significantly surpassing the uncooked control sample. Notably, pre-cooked groups (80, 90 °C) demonstrated significantly higher TDF levels compared to uncooked sample. This research offers valuable insights into the potential use of mushrooms as high-antioxidant, antimicrobial, and prebiotic food or feed supplements, with broad implications across various fields.