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Abstract

This work aimed to evaluate the effect of ethylene treatment on ripening of 1-MCP treated pear after 6 months of cold storage. Pear treated with gaseous 1-MCP at 625–650 ppb for 24 h at 0 °C was stored at 0 °C for 6 months with normal air, and treated groups were exposed to 100 ppm ethylene at 20 °C for 24 h. After that, samples were kept at 0, 10, and 15 °C for 2 weeks. Stiffness, chlorophyll fluorescence, ethylene and CO2 production of fruit were investigated during 2 weeks. Application of ethylene resumed the ripening of pear after long term storage. The results showed that fruit treated with ethylene achieved more homogeneous surface colour in comparison with non ethylene treated pears. In addition, the ethylene and carbon dioxide production of ethylene treated pears had higher values than that of control. The ethylene treatment could accelerate the softening of pear. Temperature also has significant effect on ripening during storage. This study found that ethylene treatment could accelerate the normal ripening of 1-MCP treated pears.

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The effects of regular NPK fertilization on the amounts of winter wheat yield and the amounts and proportion of different N forms (NO 3 -N, NH 4 -N, N org , N total ) of a Luvic Phaeosem soil determined in 0.01 M CaCl 2 were studied in the B1740 variant of the National Long-Term Fertilization Experiment at Karcag. According to the yield data, N and P fertilization increased winter wheat yield significantly. When applying the 200 kg N·ha -1 dose, P fertilization resulted in a more than 2 t·ha -1 yield increase, as compared to the treatments without P fertilization. K fertilization had no effect on the yield, similarly to preceding years. These findings may be adapted to fields of the Middle-Tisza Region with similar conditions to the trial site. The N forms of the soil determined in CaCl 2 reflected fertilization well. All of the fractions, but especially NO 3 -N and N total , increased significantly in response to N fertilization. Close relationships (r = 0.87–0.88) were found among the NO 3 -N and N total fractions and the N balance, which means that the amounts of NO 3 -N and N total are suitable for assessing both the N deficit and the N surplus. The strength of the correlation between the NH 4 -N content and N balance was moderate (r = 0.65). The N org fraction increased significantly as a function of N and P fertilization. These results can be explained with the yield increase. A significant correlation (r = 0.55) was found between the N org fraction and yield amounts. It can be established that organic residuals remaining on the site resulted in a significant increase in the N org content of soils. The gained results confirm that the N org fraction is suitable for the characterization of the readily mobilizable N reserves previously ignored in fertilization practice. On the basis of the presented results the CaCl 2 method is recommended for the precise estimation of nutrient requirements.

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The sugar composition of floral nectar was studied in 17 sour cherry cultivars in Újfehértó in 1997-2000. All samples contained the three most frequent sugar components: glucose, fructose and sucrose, similarly to our previous data. The ranking of the floral nectar in sour cherry cultivars based on sucrose content was the following: 'Újfehértói fürtös' and 'Pándy 48' reached the threshold value of bee visitation in at least three seasons, and a significant amount of sucrose was detected in the flowers of 'Érdi jubileum AB' and 'Érdi bőtermő' as well. The above cultivars proved to be the most valuable in Újfehértó from the viewpoint of apiculture. According to the ranking based on fructose content, which considers human sensation of taste, the most favourable cultivars were 'Újfehértói fürtös', 'Meteor USA' and 'Korai pipacs'. Based on total sugar content the secretory products preferred by bees were those of 'Újfehértói fürtös' (in three seasons); 'Korai pipacs', 'Érdi nagygyümölcsű', 'Sárándi S/Gy', 'Debreceni bőtermő', 'Kántorjánosi 3', 'Montmorency' and 'Meteor USA' (in two seasons). The ratio of nectar sugars, based on the Baker-quotient, S/(G+F), was sucrose-dominant at least in one season in 'Érdi jubileum AB', 'Érdi nagygyümölcsű' and 'Pándy 48'; hexose-rich in 'Korai pipacs', 'Kántorjánosi 3' and 'Montmorency'; all other cultivars had a sucrose-rich nectar. The nectar of all studied sour cherry cultivars possessed a composition preferred by bees. The basis of bees' nectar preference is the ratio, quantity and concentration of nectar sugar components, which were influenced by the effects of season to a high degree, differing from data in literature. From the viewpoint of nectar composition and concentration the most favourable temperature was around 20 °C.

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An attempt is outlined for the compilation of an integrated and harmonized stratified soil physical database serving hydrologic modeling, as the basis of estimating soil hydraulic parameters in the unsaturated zone. Due to the appropriate spatial and thematic resolution and data processing status, the Digital Kreybig Soil Information System (DKSIS) and Hungarian Agrogeological Database (HAD) were chosen as pedological and agrogeological data sources for describing the soil physical properties in the unsaturated zone. The DKSIS contains legacy soil data (as hy, pH, salt, OM, CaCO 3 content, etc.) in finely stratified resolution (3–5 soil layers within 1.5–2.0 m), but lacks particle size data. HAD has a coarser stratification (8–15 layers within 8–10 m) with detailed particle size data. The five-cleft FAO texture classification can serve as an interface in their joint application. The particle size and hy data pairs from the existing Hungarian Soil Monitoring (TIM) network made it possible to define the relation between FAO texture class vs. hy value, and based on the HYPRES database each FAO texture class can be characterized by typical Mualem-van Genuchten parameter sets (Wösten et al., 1999). The compiled, harmonized database characterizes the distinguished soil and sediment layers – with a thickness of at least 10 cm – for a 690 km 2 large model area, describing their thickness and texture classes to the depth of the permanent groundwater level, in every single square kilometer cell of the model area. The compiled database is indispensable in the model simulation based analysis of regional water management problems like drought, flood and inland inundation.

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Acta Biologica Hungarica
Authors:
L. Institóris
,
Dóra Kovács
,
I. Kecskeméti-Kovács
,
Anita Lukács
,
Andrea Szabó
,
Zsuzsanna Lengyel
,
A. Papp
,
L. Nagymajtényi
, and
I. Dési

Detectable interactions between NOEL (No Observed Effect Level) doses of Pb, Hg and Cd in general toxicological, hematological, and immune function parameters were investigated. The metals (Pb-acetate, 20 mg/kg; HgCl2, 0.40 mg/kg; CdCl2, 1.61 mg/kg) were combined. First, the rats received the combination Pb+Hg+Cd for 4 weeks per os. Significant difference vs. control was found only in the weight of lung and popliteal lymph node (PLN). The Pb+Hg and Pb+Cd combinations significantly decreased the PLN to 100 g body weight and PLN to brain weight ratio, and Pb+Hg also decreased the relative adrenal weight. After 12 weeks treatment with the same doses, effects on the thymus, kidney, and adrenal weights in the Pb+Hg, and thymus weight in the Pb+Cd, combination were seen. Pb+Cd also affected the white and red blood cell count and hematocrit. Combined with Hg or Cd, NOEL dose Pb showed toxicity, indicating that exposure limits may be inefficient in combined exposure situations.

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Acta Alimentaria
Authors:
D. Székely
,
L. Szalóki-Dorkó
,
M. Stéger-Máté
,
B. Szabó-Nótin
,
J. Ivanics
, and
J. Monspart-Sényi

The beetroot is typically on the table in winter in form of pickles or juice, but for its nutritional values it would deserve more common consumption. Its curative effect in great part is due to the several vitamins, minerals, and compounds with antioxidant activity. But the division of biological active compounds is very different in the parts of the root. Based on our results, we could compare the differences between the morphology and some inner contents (soluble solid content, colour, betacyanin, betaxanthin, and polyphenol contents, antioxidant activity, and some flavonoids) of two beetroot cultivars. The results of the morphological investigations showed that the ‘Cylindre’ cultivar had more favourable crop parameters than the ‘Alto F1’ cultivar. In the ‘Cylindre’ cultivar the polyphenol content and the antioxidant capacity were significantly higher than in the ‘Alto F1’ cultivar. By determination of the betanin contents of the investigated beetroots, our results showed both betacyanin and betaxanthin contents were higher in the ‘Cylindre’ cultivar. The chlorogenic acid, gallic acid, the cumaric acid have been identified based on the peaks of HPLC in the studied beetroot cultivars.

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Important differences have been reported in several countries about the level of concern in connection with food additives. In order to better understand the consumer preferences related to foodstuffs containing food additives, five hypotheses were tested with the help of a choice-based conjoint analysis. The study was performed in three European countries (Hungary, Romania, and Spain) having different risk perceptions concerning food additives. Two “model foodstuffs” were involved in the analysis: pre-packed sliced cheese (natural image) and chips (artificial image). For the creation of the conjoint cards, three attributes were selected: “preservatives” (natural/artificial), “packaging gases” (contains/does not contain) and “price” (average based on market data/+10%/+20%). Results were collected via Internet simultaneously and a total of 500 valid questionnaires were received in case of pre-packed cheese and 468 regarding chips. In the analysed countries “preservatives” had an outstanding importance — mainly in Hungary and Romania —, while “packaging gases” got lower importance during the shopping intention. “Natural preservatives” very positively contributed to the choosing of both pre-packed sliced cheese and chips. High level of willingness to pay was not observed, as well as the “price” was less important factor than the additives. Comparison of the data from three countries showed notable differences, which can determine the direction of the product planning and development.

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Acta Alimentaria
Authors:
E. Várvölgyi
,
T. Werum
,
L. Dénes
,
J. Soós
,
G. Szabó
,
J. Felföldi
,
G. Esper
, and
Z. Kovács

Time consuming and expensive methods have been applied for detection of coffee adulteration based on the literature. In the present work, an optical method (vision system) and the application of an electronic tongue is proposed to reveal the addition of barley in different proportion to coffee in ground and brewed forms. In a range of 1 to 80% (w/w) Robusta coffee was blended with roasted barley. Principal Component Analysis (PCA) accomplished on vision system image data showed a good discrimination of the adulterated samples. The results of Polar Qualification System (PQS) data reduction method revealed even small differences in the right barley content order by point method approach. With Partial Least Squares (PLS) regression the amount of barley in Robusta was predicted with high R2 (0.996) and relatively low RMSEP (∼2%) values in case of vision system data processing. Considering electronic tongue measurements, PCA results showed a good discrimination of samples with higher barley concentration. Misclassification was found in the low concentrated area by Lienar Discriminant Analgsis (LDA). To obtain an accurate model for barley content prediction in coffee, the most sensitive sensor signals were used to apply PLS regression successfully (R2=0.97, RMSEP=3.99% (w/w)).

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Acta Alimentaria
Authors:
G. Gulyás
,
L. Czeglédi
,
B. Béri
,
S. Harangi
,
E. Csősz
,
Z. Szabó
,
T. Janáky
, and
A. Jávor

The aim of this study was to investigate the differences in the proteome patterns of musculus longissimus dorsi between Charolais bulls slaughtered at 500 kg and 700 kg live weight using two-dimensional difference in gel electrophoresis (2D-DIGE) and liquid chromatography-mass spectrometry (LC-MS). Three hundred fifty protein spots were visualised on gels of which 10 showed different expression levels (P<0.05) between groups. After mass spectrometric analysis of spots, beta-enolase (ENO3) in five different spots, alpha-enolase (ENO1), triosephosphate isomerase (TPI1) in two different spots, alpha-actin (ACTA1), and heat shock protein beta-1 (HSPB1) were identified. ENO3, ENO1, TPI1, and ACTA1 had higher expression levels in bulls of 700 kg live weight group. ENO3, ENO1, and TPI1 are involved in energy metabolism, while ACTA1 is a structure protein in skeletal muscle. Up-regulation of heat shock protein beta-1 (HSPB1), which protein is reported to have correlation with tenderness, was observed in 500 kg weight group. Our result demonstrates that proteomic tools are useful in identifying markers associated with muscle development.

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Acta Alimentaria
Authors:
P. Penksza
,
R. sárosi
,
R. Juhász
,
K. Manninger-kóczán
,
B. Szabó-Nótin
,
L. Szakács
, and
J. Barta

The aim of the present study was to investigate whether the Jerusalem artichoke powder produced by a simple drying method is suitable for replacing inulin in dairy products and in fat replacer mixtures. Rheological properties of milk drinks were tested by rotational method measuring the flow curve and fitting the Herschel-Bulkley model. The Jerusalem artichoke powder showed similar rheological behaviour as the commercially available inulin and proved to be a more effective thickener in milk drinks as indicated by the higher consistency values at the same concentration. Panelists found milk drinks prepared with Jerusalem artichoke powder to have similar sensorial quality as prepared with inulin. Fat replacer mixtures were tested by oscillatory tests using amplitude sweep method. The samples containing Jerusalem artichoke powder had lower complex viscosity and initial G’ and G” values indicating weaker gel forming properties compared to inulin. However, lower slope of G’ and G” indicated their better spreadability. The organoleptic texture properties of fat replacer prepared with Jerusalem artichoke powder proved to be slightly better than that of the inulin containing mixture. Based on our results, the Jerusalem artichoke powder seems to be suitable to replace inulin as a natural additive in certain food products.

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