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Abstract

For a long time, olive oil has been considered for formulation of biopharmaceuticals and received a prestigious place in cuisine for its unique organoleptic and nutritional properties. Nevertheless, oxidation of fatty acids in olive oil provides short shelf-life and undesirable organoleptic properties. Thus, microencapsulation of olive oil is a considerable promising approach to maintain its quality and biological activities. The objective of this investigation was to prepare extra virgin olive oil microcapsule by sequential technologies, such as water emulsification of olive oil with wall material (matrix) and freeze drying of emulsion. The effect of wall material composition was examined to prepare microcapsule of extra virgin olive oil. Different ratios of wall materials such as maltodextrin (MD), carboxymethyl cellulose (CMC), and gum arabic (GA) were used. Furthermore, effects of emulsification technologies, such as homogenisation with rotor–stator homogeniser (RSH) and cross-flow membrane emulsification (CFME) were investigated. The stability of emulsion was higher when emulsion was prepared by RSH; however, the droplet mean diameter (D32) was lower in case of RSH compared to CFME. The highest encapsulation efficiency (EE) was found as 68.96 ± 2.6% when CFME was adopted and composition of wall materials was 15 g MD, 15 g GA, and 5 g CMC.

Open access
Acta Alimentaria
Authors:
M.K.J. Szentmiklóssy
,
E. Jaksics
,
A. Farkas
,
É. Pusztai
,
S. Kemény
,
R. Németh
, and
S. Tömösközi

Abstract

Rye is an important raw material of bread due to tradition and its favourable nutritional and technological qualities. Despite the beneficial fibre composition, a special group of short-chain carbohydrates, the so called FODMAPs (fermentable oligo-, di-, monosaccharides and polyols) may cause problems for patients with irritable bowel syndrome. The aim of our work was to investigate the non-starch carbohydrate (dietary fibre compounds, short-chain carbohydrates) composition of rye varieties, and of their novel milling fractions obtained from industrial milling trials and test loaves made from them. Regarding fibre and short chain carbohydrate composition, rye varieties did not show significant differences. In new subfractions, fibre and FODMAP composition were described, among profiles most of them differ from commonly used flours, independently from variety. The yeast fermentation and baking caused a decrease in water-extractable arabinoxylan content, at the same time increased the substitution pattern of water-extractable arabinoxylans. Furthermore, breadmaking process decreased the fructan content, and therefore increased the fructose level, thus modifying the short-chain carbohydrate composition. Based on our knowledge, this research is among the first ones investigating the fibre and short-chain composition of rye from the seeds to the consumable final products.

Open access

Abstract

Coatings of rice flour (RF), reinforced or not with rosemary essential oil (ROS), were used to evaluate changes in the internal quality of quail eggs stored at room temperature. Quality parameters [egg weight loss (EWL, %), Haugh unit (HU), yolk index (YI), albumen and yolk pH], microbiological (counts of total aerobic mesophilic bacteria and Enterobacteriaceae) and sensory (colour, aroma, odour, texture, taste, and general acceptability) parameters were evaluated during the experiment. Compared to the number of total aerobic mesophilic bacteria on the shell of uncoated eggs (2.02 ± 0.49; 1.78 ± 0.20 log10 CFU mL−1), RF/ROS exhibited significant inhibition effects for these bacteria on 0. (1.16 ± 0.25 log10 CFU mL−1) and 21. (0.84 ± 0.11 log10 CFU mL−1) days of storage at room temperature. On days 7, 14, and 21, RF had no effect on HU (P > 0.05), but eggs coated with RF/ROS had significantly higher HU (P < 0.05) than uncoated eggs from day 14, maintaining grade AA (73.88 ± 2.67) on day 21, while uncoated eggs had grade A (68.90 ± 1.55) at that time. The RF coating reinforced with ROS was a bioactive, efficient, and safe formulation for application based on internal quality, microbiological and sensorial aspects of quail eggs.

Restricted access

Abstract

Flagellation is one of the major virulence factors of Campylobacter jejuni (C. jejuni), enabling bacterial cells to swarm in rather high viscous fluids. The aim of this study was to determine the impact of the surrounding viscosity on the expression of motility related genes of C. jejuni. Therefore, bacterial RNA was extracted from liquid cultures as well as from bacterial cells recovered from the edge and the center of a swarming halo from high viscous media. The expression pattern of selected flagellar and chemotaxis related genes was investigated by RT-PCR. Higher mRNA levels of class 1 and lower levels of class 2 and 3 flagellar assembly genes were detected in cells derived from the edge of a swarming halo than in cells from the center. This indicates different growth states at both locations within the swarming halo. Furthermore, higher mRNA levels for energy taxis and motor complex monomer genes were detected in high viscous media compared to liquid culture, indicating higher demand of energy if C. jejuni cells were cultivated in high viscous media. The impact of the surrounding viscosity should be considered in future studies regarding motility related questions.

Open access

Abstract

Pectobacteriaceae are plant pathogens responsible for serious diseases on many crops of interest including potato. Currently, regarding the several disadvantages of conventional control by chemicals, the application of bio-agents as alternatives is increasingly being explored. The present investigation was conducted in order to evaluate the antibacterial activity of the fungal strain Trichoderma asperellum T34 as an antagonist against phytopathogen Dickeya solani on tubers of three potato varieties (Agata, Monalisa, and Picobello). For this, half-tubers were inoculated by T34 suspension with concentrations of 103 and 105 cells mL−1 at 6, 9, and 12 h before bacterial infection (D. solani at concentrations of 107 and 108 cfu mL−1). The results of infection assays without the antagonist indicated that Picobello variety was the least sensitive to soft rot, Monalisa and Agata varieties showed medium and high sensitivity, respectively. The antagonism assays revealed strong antibacterial activities, manifested by the regression of softened tissues gradually with the time of preincubation with T34, leading to a complete disappearance of disease symptoms using 12 h. Hence, the application of antagonistic Trichoderma strains as antimicrobial agents in the control of harmful plant pathogens is a subject of great interest and can be considered a promising strategy to handle soft rot diseases.

Restricted access

Abstract

Germalus kozari sp. nov. (Hemiptera: Heteroptera: Lygaeoidea: Geocoridae) is now described. Comparative notes, keys, diagnoses, and distribution data to allied Indomalayan species is provided. Germalus greeni is reported for the first time from outside of India and Sri Lanka.

Open access

Abstract

Nemoura kozari sp. n. is described on the basis of morphology of male adults collected in the Eastern Carpathians. The new species is classified as a member of the Nemoura marginata species group. It was found in medium elevations of the Krasna Mts, Ukraine, and the Rodna Mts, Romania, inhabiting slowly flowing, small brooks. New diagnosis of the marginata group and enumeration of its members are provided.

Open access

The categorisation of plant species according to their life form has a long history in plant ecology. The most popular system worldwide and also in Hungary is Raunkiaer’s categorisation according to the position of buds (meristems) surviving the adverse season. The original system contains only seven categories, resulting in high diversity within each category. Therefore, different refinements are suggested. This paper aims to apply an internationally accepted refinement of Raunkiaer’s categorisation, the Ellenberg and Mueller-Dombois system, to the Hungarian flora.

Open access
Acta Botanica Hungarica
Authors:
J. Csiky
,
L. Balogh
,
I. Dancza
,
F. Gyulai
,
G. Jakab
,
G. Király
,
É. Lehoczky
,
A. Mesterházy
,
P. Pósa
, and
T. Wirth

As part of the PADAPT project, the authors compiled the invasion biological database of the alien vascular flora of Hungary, which contains the nativeness, residence time, introduc- tion mode and invasion status of 878 alien or cryptogenic taxa. In the absence of adequate evidence, the classification of some species was only possible into uncertain, transitional cat- egories. The definitions of most categories are compatible with several international termi- nologies, but are primarily based on Central European traditions. Of the 560 taxa that have already been naturalised in Hungary, 85 are invasive, and 22 of them are transformer alien vascular plants. Only 5 of these transformers are included in the European list of Invasive Alien Species of Union concern (Ailanthus altissima, Asclepias syriaca, Elodea nuttallii, Heracleum mantegazzianum and H. sosnowskyi), which require uniform preventive interventions and treatments throughout the continent, while the rest of transformers in Hungary (e.g., Robinia pseudoacacia, Fallopia × bohemica and Solidago gigantea) draw attention to the unique, local and/ or regional invasion biological situation of the Pannonian Basin and Central Europe.

Open access