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Abstract

In this study, 14 yeast cultures from 62 isolates from traditional sourdoughs collected from 6 different regions of Turkey were selected by FT-IR identification and characterised to reveal their probiotic properties. Four yeast strains were genotypically identified and compared with FT-IR identification. In all analyses, it was observed that mostly Saccaromyces cerevisiae strain exhibited high hydrophobicity, auto-aggregation feature, and all yeast isolates in this study showed tolerance to 0.3%, even salt concentration. In addition, all yeast strains were susceptible to anti-yeasts agents, although they were resistant to all antibiotics used in the study. All selected yeast isolates exhibited high antimicrobial activity against the Staphylococcus aureus. In conclusion, this study investigated the potential probiotic properties of yeast strains isolated from sourdough.

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Abstract

Phenolic compounds provide important quality attributes to red wines interacting with the organoleptic impact of wines. Yeast mannoproteins can interact with grape phenolic compounds, responsible for colour and antioxidant activity of wines. The aim of this work was to perform oenological characterisation and specific selection of Calabrian strains of Saccharomyces sensu stricto. Among the considered traits, the aptitude of the yeast to preserve grape pigments and colour intensity was included. Among the best six yeast strains – Sc2731, Sc2742, Sc2756, Sc2773, Sc2774, and Sc2823 – strain Sc2742 exhibits the highest Folin–Ciocalteu index and strain Sc2774 the highest colour intensity. These two selected yeasts may be used as starter for the production of red wines in order to preserve grape pigments and colour intensity.

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Abstract

Sea buckthorn (Hippophae rhamnoides) with high antioxidant capacity is distributed all over the world, but has never been used as a natural antioxidant in oils to replace synthetic antioxidants. Therefore, this study was performed to investigate the effectiveness of sea buckthorn extract in comparison to a common natural antioxidant rosemary extract and a synthetic antioxidant on retarding lipid oxidation. First the extracts were characterised, and it was found that sea buckthorn extract had higher polyphenol contents, radical scavenging activity, and higher antioxidant capacity. Then the proper concentrations for the use of these antioxidants were determined. Additionally, the progress of lipid oxidation during cycles of frying was assessed in terms of free fatty acids content, peroxide value, p-anisidine value, TOTOX value, colour, total polar compounds, and Induction period. The general order of effectiveness for inhibition of high oleic sunflower oil degradation during frying was: sea buckthorn > BHT > rosemary > control (P <0.05).

Open access
Acta Alimentaria
Authors: C. Cano-Molina, A. López-Fernández, N. Díaz-González, R. González-Barrio, N. Baenas, M.J. Periago, and F.J. García-Alonso

Abstract

Tomato is rich in different bioactive compounds, especially the carotenoid lycopene, which intake is associated with various health benefits. Post-harvest use of ultraviolet light (UV) and light-emitting diode (LED) has been shown to increase the concentration of tomato bioactive compounds. The aim of this study was to evaluate the effect of ultraviolet (A and C) and red-blue LED light on the concentration of carotenoids during a 7-days storage trial of mature green tomatoes. Exposure to combined UV and LED light nearly doubled the total carotenoid concentration and had no negative impact on sensory attributes.

Open access

Abstract

The contribution of food production to the environmental burden is considerable, therefore, numerous countries have been trying to create a sustainable food supply chain to ensure food and nutrition security. The scope of this study was to analyse the association between water footprint and healthiness based on dietary records. Furthermore, it was aimed to create a classification of integrative dietary indicators of sustainable nutrition. With these methodological aims, the dietary records of 25 healthy adults were assessed. The dietary quality scores and dietary water footprint were calculated and Spearman's rank correlation was tested between them. The indicator nutrients were classified based on their advantageous or disadvantageous health impact and association with water footprint. There was a significant positive correlation between the meat consumption and water footprint, while significant negative correlations were found between the dietary quality score and water footprint and dietary quality score and meat consumption (P < 0.05). Protein, energy, sodium, and saturated fatty acids as integrated indicator nutrients could be identified for both dietary quality and water footprint. The improvement in dietary quality could simultaneously decrease the dietary water footprint. The integration of environmental impact into the analysis of diets could be the future direction in the counseling practice of nutritionists.

Open access

Abstract

After wheat, rye is the second most important raw material for bread and bakery products, and it is one of the most excellent sources of dietary fibres and bioactive compounds. Besides, rye is utilised in more and more other food products as well, such as breakfast cereals, porridges, pasta, snack products, etc. Interestingly, its production is decreasing worldwide, probably because of the expansion of other cereals (e.g. triticale), but also the effect of climate change can also play a role therein. However, there is no doubt that scientific research aimed at studying the possible health benefits and the potential of rye in the development of novel food products has intensified over the past decade.

The aim of our paper is to make a comprehensive review of the latest results on the compositional and technological properties of rye that fundamentally influence its utilisation for food purposes. Furthermore, this review aims to identify the current development directions and trends of rye products.

Open access

Abstract

Nitrate and nitrite ions taken from food are the sources of bioavailable nitric oxide (NO) in the nitrogen cycle. Some beneficial effects of honey on health are attributed to the ability of honey to increase NO production. The variation of nitrate and nitrite levels of honey samples collected from different Anatolia regions were clarified using capillary electrophoresis technique. The sensitivities of both anions were improved with the application of the sample stacking method. Separation buffer consisted of 30 mmol L−1 formic acid and 30 mmol L−1 sodium sulfate at a pH of 4.0. The CE technique revealed that 18 honey samples contained nitrate anion ranged between 2.53 and 31.8 mg kg−1. Nitrite amounts were found in lower amounts in the honey samples as between non-detected and 0.533 mg kg−1. The observed differences in nitrate levels between honey varieties may be a way to determine honey's origin.

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Szélerózió okozta talaj-, humusz- és tápanyag-áthalmozás különbségeinek feltárása különböző szerkezeti adottságú csernozjom talajokon terepi szélcsatorna kísérletek alapján

Exploring the differences in soil, humus and nutrient accumulation caused by wind erosion on chernozem soils with different structural properties by field wind tunnel experiments

Agrokémia és Talajtan
Authors: Farsang Andrea, Barta Károly, Szatmári József, and Bartus Máté

Kutatásunk során Magyarország két dél-alföldi réti csernozjom talajú területét vizsgáltuk azon céllal, hogy in situ körülmények között számszerűsítsük a különböző szélesemények által okozott talajveszteség mértékét, az ezzel együtt járó humusz- és tápanyagáthalmozás nagyságrendjét, valamint a két terület defláció érzékenységében tapasztalt különbségek okait.

Vizsgálati területeink Békés megyében, Makótól K-re mintegy 10 km-re, Apátfalva külterületén, valamint Csongrád megyében Szegedtől ÉNy-ra 2 km-re helyezkedtek el. Kutatásunk célkitűzései az alábbiak voltak: terepi szélcsatornás mérésekre alapozott laboratóriumi mérések alapján különböző szerkezeti állapotú csernozjom talajokra meghatározni

  1. az indítósebességet,
  2. a szélerózióval áthalmozott szedimentben mért makroelem, és humuszanyag feldúsulását,
  3. valamint az ezekre ható talajtani tényezőket.

A hasonló mechanikai összetételű, Szeged és Apátfalva melletti réti csernozjom talajok aggregátum összetételében, valamint a CaCO3 és humusztartalomban megfigyelhető különbségek hatására a Szeged melletti csernozjom mintaterület talaja defláció érzékenyebb. A Szegedtől É-ra eső csernozjomokon 6,5–9,0 m s–1 közötti indítósebesség értékeket mértünk, míg Apátfalván 13,0 m s–1 volt az indítósebesség értéke. Az apátfalvi terület talajának magasabb karbonát- és humusztartalma, valamint aggregátum összetételében mért magasabb morzsa arány az indítósebességérték növelésének irányába hat. A feltalajban a 0,5 mm-nél kisebb aggregátumok magasabb aránya következtében nemcsak kisebb indítósebesség értékeket, hanem nagyobb áthalmozódó talajmennyiséget, valamint ezzel együtt nagyobb mennyiségű humusz- és foszfor elmozdulást mértünk az egységesen 10-10 perces fújatási kísérleteink alkalmával a szegedi mintaterületen. Megállapítható tehát, hogy egyazon talajtípusba eső, s azonos textúrájú (homokos vályog) talajok esetében az aggregátum összetételben, valamint a CaCO3 és humusztartalomban megfigyelhető eltérések hatására jelentős különbségek tapasztalhatók a defláció érzékenység, az indítósebesség, a szediment szállítás módja és a humusz- és elemáthalmozás mértéke között.

In our research, two Chernozem soil areas were examined in the southern part of the Great Hungarian Plain in order to quantify the amount of the soil loss, humus and nutrient transport caused by different wind events and in order to show the causes of the differences in the sensitivity of deflation between the two areas.

Our study areas were located in Békés County, one of them was near Apátfalva, about 10 km east of Makó, and the other one was 2 km northeast of Szeged in Csongrád County. Our in situ wind tunnel experiments were accomplished on 2–4 June 2011 at Apátfalva and in July 2013 in Szeged. The objectives of our research were the followings:

  1. determination of the enrichment ratios for humus, macro- and microelements in the wind eroded sediments in the case of Chernozem soils with different structures based on field experiments and laboratory measurements;
  2. determination the affecting actual soil factors;
  3. estimation of soil loss and element rearrangement trends on Chernozem arable lands under different wind velocity on plot scale.

Because of the differences in the aggregate size distribution, CaCO3 and humus content, Chernozem soil near Szeged is more sensitive to deflation than near Apátfalva. Threshold friction velocity was measured between 6.5 and 9.0 m s–1 near Szeged, while the same parameter was 13.0 m s–1 at Apátfalva. The higher carbonate and humus content and the higher crumb ratio of the soil on the Apátfalva area result increasing threshold friction velocity. Due to the higher proportion of aggregates smaller than 0.5 mm in the topsoil, we have measured not only lower threshold friction velocities, but also a larger quantity of transported soil and a larger humus and phosphorus loss during the uniform 10-10 minute long wind tunnel experiments in the Szeged sample area. It can be concluded that even in spite of the same soil type and same texture there are significant differences between deflation sensitivity, threshold friction velocity, sediment transport mode, humus and nutrient transportation because of the significant differences in aggregate size distribution, CaCO3 and humus content.

It means that the agronomic structure of the soils greatly influences the mitigation and aggravation of the soil the stress effects caused by climate change. Extreme weather situations have drawn attention to the fact that improperly applied cultivation methods, tools, and overuse of Chernozem soils can modify the soil structure. One of the most serious affect is the dusting of the surface layer of the soil. During this process the larger macroaggregates disintegrate into microaggregates and the resulting smaller fractions are more exposed to wind erosion.

The dust load affecting our settlements is mainly originated from arable lands. The mitigation of this emission is fundamentally based on the regulation of land use, farming practices and deflation. “Best Management Practices” (BMPs) mean a group of selected tools that can reduce or eliminate the transport of pollutants from diffuse sources before, during and/or after agricultural activities. However, these diffuse agricultural loads caused by wind erosion can only be quantified if the magnitude and spatial movement of the dust and pollutants is monitored.

Open access

Abstract

In the case of fruit syrups, consumers prefer thicker, deep-coloured ones because they remind them of good old homemade ones. Physical properties – as viscosity, colour, refractive index, soluble solid content (SSC), and electrical impedance - of fruit syrups flavoured with raspberry or orange juice were determined. The change of the measured physical properties was determined in three different experiments: 1. evaluating the effect of sugar and sweetener content 2. evaluating the effect of fruit juice composition and 3. evaluating the effect of sugar content on syrups containing raspberry or orange juice only. Variations in fruit and sugar content had a definite effect on the physical properties of squashes. Viscosity, SSC value, refractive index, and impedance magnitude increased with increasing sugar content and decreased with replacement of sugar with sweeteners although colour characteristics were defined mostly by the colorant added to the squash. Changes in the fruit composition of syrups could influence viscosity, refractive index, and SSC values but the magnitude of impedance showed little changes for all samples. The characteristics of squashes containing only raspberry or orange juice and different sugar content did not follow any trends, which emphasized that additives had a significant effect on the physical properties.

Open access
Acta Alimentaria
Authors: L. Červinka, P. Burg, I. Soural, V. Mašán, A. Čížková, J. Souček, V. Višacki, O. Ponjičan, and A. Sedlar

Abstract

Sauvignon Blanc represents an important grape variety. The wine made from this variety is known to have a wide range of aroma profiles from nettles to tropical fruits. Beside the raw material quality (grapes), the quality of wines can be fundamentally influenced by the technological conditions applied in the wine making process. Yeast and other microorganisms play a key role in the formation of metabolites during alcoholic fermentation. In this study, the effects of autochthonous or selected wine yeasts (Saccharomyces cerevisiae) and fermentation temperatures (15 °C and 19 °C) were tested on major monoterpenes contents of wines during the period 2016–2017. The obtained values show that the highest contents of linalool (24.36 μg L−1) and hotrienol (11.84 μg L−1) were determined in wine samples produced with active (selected) wine yeast at lower temperature. Sensory evaluation results indicated that monoterpenes can have a positive effect on the overall sensory quality of Sauvignon Blanc wines, despite the fact that their determined concentrations in the evaluated samples were not higher than their threshold values.

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