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Acta Alimentaria
Authors:
Sz. Bánvölgyi
,
T. Vatai
,
Zs. Molnár
,
I. Kiss
,
Ž. Knez
,
Gy. Vatai
, and
M. Škerget

Two novel technologies were applied in order to investigate concentration and formulation of anthocyanins for potential use in food industry. Integrated membrane process technology was applied for concentrating elderberry juice. In the first step, the juice was clarified by microfiltration, followed by a pre-concentration step with reverse osmosis. Finally, the juice was concentrated to the end concentration of 56 °Brix by osmotic distillation. The elderberry juice concentrate was formulated in a powderous form by a high-pressure process — Particles from Gas Saturated Solution (PGSS™) — using supercritical CO2. The applied carrier material was palm fat. The products with different anthocyanin-carrier ratios were measured for their colour properties (lightness, hue angle, and saturation). Colour stability was monitored for prolonged storage at different conditions (light/dark and ambient temperature/ refrigerator). The obtained powderous anthocyanin-palm fat products showed good colour stability, which gives good bases for potential applications in the future.

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Acta Alimentaria
Authors:
L. Darnay
,
A. Dankovics
,
B. Molnár
,
L. Friedrich
,
Gy. Kenesei
, and
Cs. Balla

Several scientific papers suggest that microbial transglutaminase (mTG) is capable of reducing the salt content of cured and/or heat-treated meat products (ham, frankfurters, meat ball). These scientific results are not widely known in Hungary, and as a result of this, only little experience was gathered in our meat industry. According to this lack of knowledge, our aim was to lower the curing salt to a still microbiological safe level using mTG by frankfurters, one of the most well-known heat treated meat products in Hungary. The observed technofunctional properties suggest to use mTG enzyme preparation at 0.5% concentration. This enzyme dosage can reduce the average 1.8% salt content to 1.6% and it also may contribute to extended shelf life of popular frankfurters. Our sensorial analysis revealed that the panellists have not found a loss in quality between 1.4% and 1.6% salt.

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Enzyme-linked immunosorbent assays (ELISAs) are widely used to determine gluten contamination in gluten-free and low gluten food samples. ELISA assays developed using monoclonal antibodies against known toxic peptides have an advantage in the identification of toxic prolamin content in protein extracts of different food samples, as well as raw materials. R5 and G12 monoclonal antibodies specific for two known toxic peptides used in commercially available gluten ELISA assays were applied to test toxic peptide contents in wheat relatives and wild wheat species with different genome composition and complexity. Although the R5 peptide content showed some correlation with ploidy levels in Triticum species, there was a high variance among Aegilops species. Some of the analysed diploid Aegilops species showed extremely high R5 peptide contents. Based on the bioinformatics analyses, the R5 peptide was present in most of the sulphur rich prolamins in all the analysed species, whereas the G12 epitope was exclusively present in alpha gliadins. High variation was detected in the position and frequency of epitopes in sequences originating from the same species, thus highlighting the importance of genotypic variation within species. Identification of new prolamin alleles of wheat relatives and wild wheat species is of great importance in order to find germplasm for special end-use quality purposes as well as development of food with reduced toxicity.

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Agrokémia és Talajtan
Authors:
A. Horel
,
Zs. Bakacsi
,
M. Dencső
,
Cs. Farkas
,
Gy. Gelybó
,
I. Kása
,
E. Tóth
,
S. Molnár
, and
S. Koós

A vizsgálat 42 órája alatt (2016. február 3–4.) és az előtte lévő öt hónapban összesen négy nagyobb mennyiségű csapadékesemény történt a Csorsza-patak vízgyűjtő területén. A vizsgált esőzés időszakában 21,6 mm csapadékmennyiség hullott összesen a vízgyűjtő területére 5 órás intervallumban. A csapadékesemény első órájában a patak zavarosság értéke majdnem megduplázódott, viszont így is viszonylag alacsony szinten maradt a későbbiekben mért értékekhez viszonyítva. Az esőzés kezdetét követő 7. órában emelkedett meg jelentősen a zavarosság mértéke, több mint 14-szeresére, a 13–14. órában pedig 34-szeresére nőtt a vizsgálat előtti naphoz viszonyítva. A Csorsza-patak zavarosságának nagysága nem sokkal a tetőzést követően nagy mértékben lecsökkent, 13 órával később pedig hasonló értékeket mutatott, mint a vizsgálat előtti esőzés nélküli időszakban.

A nagyobb esőzések alkalmával az alacsonyabb területeken fekvő, minimális lejtésű szántó esetében telítettséghez közeli talajnedvesség-tartalom volt megfigyelhető, míg a legkisebb talajnedvesség-tartalom ingadozás az esőzést követően a gyepes és az erdős területekre volt jellemző.

A jelen vizsgálatban összegyűjtött adatok alapján a Csorsza-patakból a Balatonba bekerülő talajhordalék mennyisége a téli időszakban, az erozív esőzések gyakoriságának ismeretében könnyebben és pontosabban becsülhető. Annak érdekében, hogy az éves átlag lebegtetett hordalék mennyiségének a becslését pontosabban el tudjuk végezni, több időszakos mérésre volna szükség.

Munkánkat az OTKA K—101065 projekt, az OTKA PD—116157 és OTKA PD—116084 kutatási projekt, valamint a Bolyai János Kutatási Ösztöndíj támogatta. Külön köszönet Mózes Mariann és Bányász Ágnes részére a laboratóriumi vizsgálatokban nyújtott segítségükért, valamint Szegvári Győző és kollégáinak a zánkai vízminták gyűjtésében való hatalmas segítségükért.

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Acta Alimentaria
Authors:
A. Nath
,
S. Mondal
,
A. Csighy
,
M.A. Molnár
,
K. Pásztorné-Huszár
,
Z. Kovács
,
A. Koris
, and
Gy. Vatai

In the dairy industry different types of prebiotics, such galacto-oligosaccharide, lactulose, lactosucrose, tagatose, lactitol, lactobiono- and glucono-δ-lactone are synthesized through different chemical and biochemical reactions (hydrolysis, transgalactosylation, isomerization, fructosyl-transfer, reduction, and oxidation) as well as microbial fermentation processes using raw whey or isolated lactose as feedstock. Lactose-derived prebiotics have several functional and nutritional values. The biochemical activities of lactose-based prebiotics are expressed in the presence of probiotics (lactic acid bacteria, yeasts, Bacillus spp.). Galacto-oligosaccharide and lactosucrose reduce the risk of bowel disorder (diarrhea), inflammatory bowel disease (ulcerative colitis and crohn’s disease), and colon cancer. Galacto-oligosaccharide helps colonic absorption of minerals (iron, magnesium and calcium) and prevents osteoporosis. Lactulose, galacto-oligosaccharide, and lactitol promote laxative activity. Furthermore, lactulose may decrease the risk of hepatic encephalopathy. Prebiotics have low calorific value and glycemic index. Galacto-oligosaccharide and tagatose reduce the risks of hyperglycemia (Type 2 diabetes) and low density lipid (lipoprotein) accumulation in blood stream. Moreover, prebiotics improve immunomodulation, which reduces the risk of respiratory infection and allergies. This review describes unique biochemical mechanisms of several types of lactose-derived prebiotics.

Open access

Abstract

The aim of our research was to study the water and ethanol extractable polyphenols of stinging nettle (Urtica dioica L.) harvested in different seasons and to determine their antimicrobial activity against certain human pathogenic and food spoiling bacteria and yeasts.

Our results indicate that the spring leaf extracts had higher polyphenol contents than the root one; however, close to the end of the vegetation period these values decreased considerably in both leaves and roots. Detection and quantification of the most abundant phenolic compounds in the spring extracts by HPLC revealed the occurrence of 12 different phenol carboxylic acids and flavonoids. Flavonoid compounds were more abundant than phenol carboxylic acids in the leaves; however, their proportion was equal in the case of the roots. Nettle leaf extracts had remarkable antimicrobial activity, the spring extracts were more efficient than the autumn ones. Escherichia coli and Staphylococcus aureus were sensitive to every leaf extract, while Listeria monocytogenes and Pseudomonas aeruginosa had reduced but remarkable sensitivity patterns. Among the yeasts, Candida glabrata was strongly inhibited by the aqueous leaf extracts. Most of the strains were insensitive to the root extracts, although Enterococcus faecalis was inhibited by the root and not the leaf extracts.

Open access
Acta Botanica Hungarica
Authors:
Cs. Molnár
,
Zs. Molnár
,
Z. Barina
,
N. Bauer
,
M. Biró
,
L. Bodonczi
,
A. Csathó
,
J. Csiky
,
J. Deák
,
G. Fekete
,
K. Harmos
,
A. Horváth
,
I. Isépy
,
M. Juhász
,
J. Kállayné Szerényi
,
G. Király
,
G. Magos
,
A. Máté
,
A. Mesterházy
,
A. Molnár
,
J. Nagy
,
M. Óvári
,
D. Purger
,
D. Schmidt
,
G. Sramkó
,
V. Szénási
,
F. Szmorad
,
Gy. Szollát
,
T. Tóth
,
T. Vidra
, and
V. Virók

The first version of the map of the Hungarian vegetation-based landscape regions were prepared at the scale of 1: 200,000 (1 km or higher resolution). The primary goal of the map was to provide an exact background for the presentation and evaluation of the data of the MÉTA database. Secondly, we intended to give an up-to-date and detailed vegetation-based division of Hungary with a comprehensive nomenclature of the regions. Regions were primarily defined on the basis of their present zonal vegetation, or their dominant extrazonal or edaphic vegetation. Where this was not possible, abiotic factors that influence the potential vegetation, the flora were taken into consideration, thus, political and economical factors were ignored. All region borders were defined by local expert botanists, mainly based on their field knowledge. The map differs in many features from the currently used, country-wide, flora-or geography-based divisions in many features. We consider our map to be temporary (i.e. a work map), and we plan to refine and improve it after 5 years of testing.

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