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MÚLT-JELEN-JÖVŐ a hazai mezőgazdasági talajvizsgálatokban

PAST-PRESENT-FUTURE in Hungarian soil analyses

Agrokémia és Talajtan
Authors:
Viktória Vona
,
István Attila Bakos
,
Zsolt Giczi
,
Renátó Kalocsai
,
Márton Vona
,
István Mihály Kulmány
, and
Csaba Centeri

The purpose of the present paper is Authors aim was to deliver a compilation of to summarize the Hungarian soil analysies methods and theas well as to present the advisory system for nutrient management advisory system. Both of them are based on several decades of work. We need to should learn from these past experiences of reasonable and good agricultural practices. We can only apply the present and future results of soil science and find out what direction should we develop, if we were aware of the results of the past and we calculate with their governing effects. The majority of our recent methods are based on historical researches and the present current statesituation of our field of scientific fieldce can only be judged and developed further if we knew the former history of the methodological findings. The recent Hungarian soil analysis system provides useful results that can be used very well today, however, the adaptation of the new international methods , learned from the follow-up of the international trends can might provide open new perspectives in for the Hungarian laboratory analyses methodology. TThe subject is extremely timely because there are hea never- met demand for cost and time effective, environmentally friendly soil analysis methods underpin how actual and hot the topic is. nowadays.

Open access

A talaj fixált ammónium-ion tartalmának hatása a talajvíz tisztulási folyamataira a szennyezőforrás felszámolását követően települési környezetben

Effects of fixed ammonium ion content of the soil on groundwater purification processes after the elimination of the pollution source in municipal environment

Agrokémia és Talajtan
Authors:
Tamás Mester
,
Daniele Cavalli
,
Dániel Balla
, and
György Szabó

Growing NH4 + content of groundwater results in increasing exchangeable and fixed ammonium ion content of the soil. NH4 + bond in the soil may go again into solution parallel with the dilution of the soil solution but at a slower rate than fixing. This process influences significantly the NH4 + content of the soil. In settlements with no sewerage system the high NH4 + content of sewage flowing out of uninsulated septic tanks may increase the fixed NH4-N content of the soil that could have a significant effect on the quality of groundwater even after the potential disappearance of pollution sources.

In this study the effects of the fixed NH4-N content of the soil around an uninsulated residential septic tank on the purification processes of the groundwater were investigated. The septic tank in the study area was dismantled in 2014 after 27 years of operation as a sewerage system was constructed. When the tank was still in operation in 2012 and 2013, very high, 55–75 mg l-1 NH4 + content was measured in the water of the monitoring well 1 metre from the tank in the course of seasonal sampling. When sewage outflow was terminated in 2014 concentrations decreased right away but even 5 years after pollutant supply was stopped, concentrations (35–57 mg l-1) highly exceeding the pollution limit (0.5 mg l-1) were measured. Considering this very high concentration, it can be assumed that great amount of NH4 + is still released into the groundwater.

In order to prove this, the exchangeable and fixed NH4-N and NO3-N contents of the soil were determined by 20 cm down to a depth of 4 metres (2019). The measurements indicated the significant accumulation of exchangeable and fixed NH4-N in the zone between 220 and 400 cm. Highest fixed NH4-N concentrations of 457 mg l-1 were found between 220 and 240 cm suggesting that sewage outflow was most intense at this depth. Slow decrease in concentrations can be observed in deeper zones but concentrations higher than 350 mg l-1 were measured between 220 and 380 cm. Based on correlation analyses, the quantity of fixed NH4-N shows no correlation with the soil texture thus it can be stated that the vertical pattern of NH4-N content is determined dominantly by sewage outflow and its depth. In the unsaturated zone of the borehole a significant accumulation of NO3-N was also identified. The maximum of NO3-N was found in the zone between 100 and 140 cm. The peak nitrate calculated for NO3 - ion with a value >1300 mg kg-1 is 2.5 times the limit set for the nitrate content of the geological medium.

Based on the results, exchangeable and fixed NH4-N contents in the soil are still very high, 5 years after sewage outflow was stopped. The continuous solution of this component still contributes to the high NH4 + content of the groundwater. As a result, the contaminated soil in the immediate environment of the septic tank is still a pollution source.

Open access

Abstract

In the last years, an alternative and convenient way to composting and/or bio-gasifying food waste is represented by the extraction of high value bioactive components from such materials. In particular, essential oils contained in matrices such as orange or lemon peels may represent high value bioactive components for the nutraceutical and pharma industry. In recent years, microwave assisted processes have been considered for use in solvent-free extraction. However, the microwave assisted extraction is often performed in very simple microwave systems, without an accurate control, if any, of the power release.

In this work, the linear tuning of microwave power for the extraction of bioactive components from citrus peels is discussed, with emphasis on the consequent process yield and extract characteristics. Chemical analysis of the extracted mixture showed the presence of quite a number of active molecules of relevant interest for pharmaceutical and nutraceutical industries, such as glycoside flavanone (Hesperidin and Eriocitrin) in lemon peels, and polymethoxylated flavones (Nobiletin and Sinensetin) in orange peels.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Gabor Zsivanovits
,
Dida Iserliyska
,
Maria Momchilova
,
Petya Sabeva
, and
Zarya Rankova

Abstract

Bicolor (Rosaline) and black (Regina) sweet cherry cultivars were treated with chitosan-Ca-lactate and chitosan-alginate solutions. The chitosan coating is biocompatible, nontoxic and possesses antimicrobial activity. The sample series (five replicates of thirty pieces from each variety and each treatment, and a control) were refrigerated at 4 °C for 21 and 28 d, to the end of shelf-life. Physical (visual sorting, weight loss and texture of intact fruit), physicochemical (TSS, antioxidant activity, and pH of the pulp), and microbiological properties (total number of microorganisms, Escherichia coli, fungi and yeasts) were investigated weekly. For the last week only the Regina cultivar had acceptable appearance, the other cultivar was discarded after 21 d. The chitosan-alginate treatment preserved the texture, showed smaller weight loss, higher antioxidant preservation and smaller microbial contamination than the samples with chitosan-Ca-lactate on both cultivars. Based on the results, the edible coating can help to preserve the nutritional value of fresh fruit and this technology can be useful in preparing the ready-to-eat fruit salads or in decoration of confectionery products.

Open access

Abstract

Grafting is a connection of two plant tissues, which are forced to develop vascular connection and grow as a single plant. Vegetable grafting has been used in Solanaceae family and Cucurbitaceae family for several reasons e.g. increasing tolerance against biotic and abiotic stresses, improving plant growth and yield. Fruit quality and appearance of vegetables may be influenced by grafting methods. Researchers have found contradictory results of fruit quality and appearance even in eggplant grafting due to different production environments, types of rootstock/scion combinations. In current review, we summarise available information on the effects of grafting and different rootstocks on eggplant fruit quality.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Richard Pinter
,
Evelin Molnar
,
Khabat N. Hussein
,
Adrienn Toth
,
Laszlo Friedrich
, and
Klara Pasztor-Huszar

Abstract

The objective of this study was to research the adaptability of insects in food products. The created hamburger patties were made with pork meat and insect batter (Zophobas morio) in a 50:50 ratio and the color, pH value, water-holding capacity, roasting loss, texture, microbiological traits were studied during ten days of refrigerated storage (5 °C, vaccum packaging, air cooling). Similar products have already existed in European markets, but these are made of 100% of insect meat or with additional vegetables as an ingredient. The mixture of insect and pork could offer a more accepted texture by consumers than the other alternatives. This study showed burger patties with pork meat and insect meat offering a softer texture and darker color, while it could increase the shelf-life of raw product.

Open access

Abstract

The objective of our experiment was to investigate the rheological properties of a compound coating depending on the pre-treatment temperature regimes.

Compound coating samples were measured at six different temperatures with 2 °C resolution between 40 and 50 °C. One part of melted samples was measured by RV1 rotational rheometer at the actual melting temperatures and the other part of melted samples was filled into 9 × 9 × 9 mm cubes molds. These cubes were cooled 24 h in freezer (−18 °C) and next day the samples were warmed to room temperature for 3 hours with different temperature combinations. The solid cubes were measured with Texture Profile Analysis (TPA) test by SMS TA-XTplus Texture Analyzer at room temperature.

Results show the effect of pre-treatment on the viscosity of the coating. Furthermore, significant differences were found among the samples cooled with different cooling methods. Our results stress the importance of the correct handling of the materials for confectioners.

Open access

Abstract

Colour is one of the most important phenotypic characters of the table grape cultivars, which has high importance in the consumer's preference. This morphological trait is variable and not consistently uniform within a cultivar or even a bunch. Between harvest and consumption fruits are stored for several weeks which time is influencing the colour of the berry. In this study 10 grapevine accessions (Agaphante, KM98, Korai piros veltelini, Korona, Pinot gris, Pozsonyi, Ros de Minis, Tramini piros, T9, Zenit) were collected from the germplasm collection of the Research Institute for Viticulture and Oenology of the National Agricultural Research and Innovation Centre of Kecskemét. The samples were investigated by ColorLite Sph850 spectrophotometer. The colour of 30 berries per accessions were measured in 3 replicates per berry. The aim of this study was to evaluate the colour and the effect of cold storage. L, a, b values of each accessions were evaluated after the sampling and until a visible reduction in the quality of the grapes, at most 4 weeks with 1-week intervals from the harvest. Results showed that there is a significant difference among the cultivars in the L∗, a∗, b∗ values. The length of cold storage also has a significant effect on the colour of the accessions as the values are changing in some cases of the 1-week storage period.

Open access

Abstract

The high antioxidant capacity of tea is well-known, but the effect of flavorings like honey or lemon has been less studied. Their antioxidants can interact with each other, the global result being also affected by the brewing temperature.

The combined effect of heat (55 and 80 °C) and flavorings (acacia and honeydew honeys, lemon juice) on the total polyphenol, total flavonoid content and antioxidant capacity of black and green teas was studied.

In many cases higher antioxidant capacity was obtained at 80 °C. Teas flavored with honeydew honey had higher antioxidant capacity than those containing acacia honey. Addition of lemon decreased the antioxidant capacity of tea with honey. No synergies were confirmed in any of the compositions investigated. Vitamin C content of lemon-containing black tea was reduced by half at 80 °C compared to tea brewed at 55 °C; while honey was shown to partly prevent this loss of ascorbic acid.

Open access