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Basil has traditionally been used for a long time in medicine and gastronomy. Essential oil is the most important active substance of the drug, which influences the aroma and the effect of the plant. Although the compositions of essential oils vary in different basil cultivars, the main components are oxygenated monoterpenes and phenylpropane derivates. The high chemical variation is most likely caused by interspecific hybridization. Various factors, like genetic background, ontogenesis, morphogenesis, abiotic factors, essential oil extraction method, drying, and storage, are responsible for the variant essential oil composition.

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Apple is one of the most important fruit grown and consumed in the temperate climate region. About 2% of the European population suffers from several allergenic reactions after consumption. Presence of 7 members of Mal d 1 gene family occurring in some apples was examined by PCR. The Mal d 1.01 and 1.02 genes could be detected from 91% and 79% of apple cultivars, respectively, due to the high degree of conservative regions. The Mal d 1.04 gene has 4 functional varieties and 2 pseudo-alleles, so it is highly variable. The PCR amplifi cation with Mal d 1.06 primers gave one or two fragments with different sizes. The electrophoretic pattern is a suitable means to select apple cultivars according to their low, medium, or high Mal d 1 allergen content. Florina apple showed the single 154 bp allele, which is responsible for the small Mal d 1 allergen content in homozygote form..

Several samples gave weak signal or did not give any fragment-band on the gel, so Mal d 1.07 and 1.08 genes might have more varieties. Regarding the Mal d 1.09 gene we have found that it has conservative sequences in different apple cultivars and does not have too many varieties.

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Effects of mixed cultures of Saccharomyces cerevisiae Levuline FB — higher ethanol tolerance — and different Kluyveromyces strains — higher inulinase activity — on the production of ethanol from Jerusalem artichoke extract were investigated. Among the investigated strains, combination of S. cerevisiae and K. marxianus strain Y00959 with simultaneous saccharification and fermentation gave the best efficiency (76%) of bioconversion. The optimal ratio of mixed cultures was determined to be 1:1 of K. marxianus and S. cerevisiae. Central composite design (CCD) was adapted to find the optimum initial substrate concentration and inoculum size for the maximal production of ethanol from Jerusalem artichoke juice. The optimum fermentation conditions were found to be 24% (m/w) substrate concentration and 45 OD600nm ml/100 ml inoculum size of mixed culture. Use of these conditions, about 10.67% (v/v) was produced at 148 h of alcoholic fermentation given. Results of this work provide benefits of mixed culture on production of bioethanol from Jerusalem artichoke.

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Wild Origanum vulgare populations in Hungary have been analysed. In 2010 the morphological variability of 11 populations in five shires was investigated, the features of habitats were also described. The difference in elevation between the lowest and highest locality is 630 m. Nine plant associations, four soil types, variable pH between 4.81–7.96 and humus content from 0.54% to 6.97% were determined. Among the examined individual plants the maximum length of stem was 107 cm, the highest number of branches was 14 pairs, furthermore procumbent and mellow stems were also found. The defined colours of inflorescences are dyes of pink or purple. Despite to these we found individuals in one population with white flowers, green bracts and calyces.

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Acta Alimentaria
Authors:
K. Szekér
,
J. Beczner
,
A. Halász
,
Á. Mayer
,
J.M. Rezessy-Szabó
, and
P. Gálfi

The adhesion of twenty-six Lactobacillusstrains to two intestinal cell lines (Caco-2P and IEC-18) and 21 Bifidobacteriumstrains to Caco-2P cells was investigated. Non-specific adherence was determined on the surface of culture plates. The effect of short chain fatty acids (SCFA) on epithelial cells, and bacterial adhesion were investigated by Na-n-butyrate treatment. The adherence of LAB and bifidobacteria greatly varied in a strain-dependent manner. The adherence of LAB was better to IEC-18 cells than to Caco-2P cells, and bifidobacteria adhered better to Caco-2P cells than the LAB. Some strains adhered well or even better to the background than to the cells, which queries the specificity of adhesion of these strains. Na-n-butyrate treatment stimulated the differentiation of IEC-18 cells and therefore increased the number of adherent bacteria, probably because only the cell surface increased not the number of epitopes.

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Ground ivy (Glechoma hederacea L.) is one of the prosperous plants for the food-industry as natural antioxidant. This fact led us to examine the chemical diversity of six ground ivy populations situated in different natural habitats and to analyse the effect of the harvesting time. Total phenolic content, chlorogenic acid, and rutin content, as well as the antioxidant capacity showed significant differences due to the harvest time. The highest total phenol content (115 mg g–1 GAE) and the strongest antioxidant activity (53.3 mg g–1 AAE) were measured in the population originated from Budapest (GLE 6), harvested in July. The highest chlorogenic acid (357 mg/100 g) and rutin (950 mg/100 g) contents were detected in the July harvested samples from the Soroksár Botanical Garden population (GLE 1). According to our results, the collection time has significant effect on the total phenolic content – first of all on the chlorogenic acid and rutin accumulation levels of ground ivy, while the influence of the habitat seems to be less important.

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Acta Alimentaria
Authors:
E. Szabó
,
É. Gelencsér
,
E. Kovács
,
A. Jánosi
,
K. Takács
, and
E. Kiss

In our research we studied the occurrence of the main apple allergen coding gene-families (Mal d 1, Mal d 2, Mal d 3, Mal d 4) in 16 different and most preferably consumed apple varieties. After the DNA isolation by Wizard method the simple PCR reaction was used to examine the apple allergen-coding genes. To identify the presence of the four allergenic protein-coding genes two primer pairs were chosen. The presence of these allergens in most apple varieties could be confirmed. According to our results two varieties — Jonathan and Granny Smith — were found to contain the lowest amount of the coding genes of the allergenic apple proteins studied by us. Besides this, polymorph pattern was obtained by the use of Mal d 1 primer, which may lead to determine apple varieties with small amount of Mal d 1 allergens.The confirmation study of the presence of potential apple allergens by RNA and protein techniques is our plan in the near future.

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

The aim of the present study was to investigate whether Jerusalem artichoke powder produced by a simple drying method is suitable for replacing inulin as a dietary fibre in bread. Baking probe was performed using 0, 5, and 10% Jerusalem artichoke (JA) powder and 2.5 and 5% inulin (IN) on wheat flour weight basis. Functional properties of bread loafs were tested by Stable Micro System TA TX2i Texture Analyser (SMS) after 0, 24, 48, and 72 h storage. It was concluded that using inulin as a dietary fibre did not deteriorate the baking quality of bread, however, shelflife slightly decreased. Jerusalem artichoke powder compared to inulin had similar effect on the baking properties of bread. Based on our results, JA powder proved to be a promising alternative for fibre enhancement in bread.

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In the case of a widely used spice — Origanum vulgare subsp. hirtum — the effect of different drying methods (natural, and by using dryers at temperatures of 30°C, 40 °C, 45°C) was investigated referring to the essential oil amount and composition in the final material. The sensory characteristics of olive oils flavoured by the oregano samples were also determined. The essential oil amount and the area percentage of its main component — carvacrol — were significantly influenced by the different drying temperatures. Compared to the natural way of drying in the case of the essential oil content the drying temperature of 40°C and 45°C was preferable for the higher amounts. Referring to the carvacrol area percentage the drying temperature of 30°C resulted in the highest amounts (89.74±0.28%), that was affirmed by the sensory analysis as well; based on the taste descriptions the consumers found it the most pungent one. According to our results sensory analysis data in most of the cases corresponds to the GC-MS measurements and give a much more complex characterisation of a spice.

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