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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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Abstract

Background

Little is known on the abundance of the pathogens Bacillus anthracis and Burkholderia pseudomallei in environmental samples in Cameroon. Therefore, 100 respective samples were assessed in a proof-of-principle assessment.

Methods

DNA residuals from nucleic acid extractions of 100 environmental samples, which were collected between 2011 and 2013 in the Mapé Basin of Cameroon, were screened for B. anthracis and B. pseudomallei by real-time PCR. The samples comprised soil samples with water contact (n = 88), soil samples without water contact (n = 6), plant material with water contact (n = 3), water (n = 2), and soil from a hospital dressing room (n = 1).

Results

B. anthracis and B. pseudomallei were detected in none of the samples assessed.

Conclusion

The results indicate that at least a quantitatively overwhelming, ubiquitous occurrence of B. anthracis and B. pseudomallei in the environment in Cameroon is highly unlikely. However, the number and choice of the assessed samples limit the interpretability of the results.

Open access

Abstract

Napping is one of the rapid sensory profiling methods, which was established recently to meet the needs of sensory and consumer researchers. This approach provides a holistic evaluation of the tested sample through their positioning in a 2-dimensional space. The protocol of the analysis is somewhat different from the traditionally applied descriptive methods, like Quantitative Descriptive Analysis. In our review, we focus on the applicability of Napping in the field of fermented goods. The accompanying procedures are also investigated (typically Flash Profiling, CATA, and further methods), in order to understand how the combined datasets facilitate the understanding of the sensory characteristics of the products.

Open access
Progress in Agricultural Engineering Sciences
Authors: Anna Visy, Karina Ilona Hidas, Annamária Barkó, Lien Le Phuong Nguyen, László Friedrich, and Gábor Jónás

Abstract

Consuming enough protein is a very important part of a balanced and healthy diet. Complete proteins are those in which all essential amino acids are present. In meat products, like hams, many different reactions occur during ageing and storage. For example, the production of free amino acids or the production of biogenic amines is formed by decarboxylation. In this study, the presence of these amino acids and biogenic amines, as well as the quality properties of cured hams during curing and ageing, were investigated.

The meat samples were immersed into 100 g L−1 NaCl brine. The curing took 20 days, followed by smoking and ageing for 35 days (12 °C, 75% RH). The wet-cured ham samples were analysed for changes in NaCl concentration (at 3 parts: surface, core, bottom layer). Moreover, color, water activity, denaturation temperature and enthalpy (Differential Scanning Calorimetry), free amino acids (FAAs) and biogenic amines (BAs) were also evaluated.

Open access

Abstract

One of the most important components in spreads is the fat phase. The characteristics of the used fat determine most of the quality factors of the products such as viscosity, texture, colour, shelf life, etc. In these kinds of products, the commonly used fat is palm fat, however, in recent years it has had a bad press due to its negative environmental impact and health concerns. Therefore, the aim of our research was to develop a palm oil free hazelnut spread. We investigated the effect of replacing the fat in the fat phase with milk fat or coconut fat to the apparent viscosity, colour and texture properties of the product. According to our results the palm fat had the highest and coconut fat had the lowest viscosity. In texture analyses palm fat and milk fat showed no significant difference in hardness and in work of penetration. Coconut fat was significantly different in every texture attributes from the other samples. In the case of colour measurement all samples were significantly different. Despite the observed differences in some parameters the suitability of milk fat for hazelnut spread production should be further investigated (sensory analyses, shelf-life).

Open access

Abstract

The aim of this study was to investigate microencapsulation of palm oil fractions (palm olein (POL) and 90% palm olein+10% palm stearin (POS)) using skim milk powder (SMP) and maltodextrin (MD) by spray drying. Twenty-seven emulsions with POL were prepared to determine appropriate solid content (SC) and oil/coating material ratio (O/CM) of the emulsions to be fed into the spray dryer. Emulsion properties, such as viscosity and stability, were affected by SC and coating materials. The effects of coating materials used in microencapsulation of POL and POS were also tested by using different ratios of SMP and MD. The microencapsulation efficiency (69.28–84.97%), the microencapsulation yield (14.50–31.79%), and the peroxide value (4.12–7.07 meq O2/kg oil) of the powders were affected by the coating materials (P < 0.05).

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Abstract

In the current study, cakes were prepared with the addition of different levels of chia gel obtained by soaking 1 part of chia seeds in 9 parts of water by weight. Mix was allowed to stand for 30 min for gel formation and seeds were left in the gel and later incorporated into the batter. The addition of chia gel to cake batter to partially substitute the fat from the basic recipe (control) resulted both in improved quality characteristics at all levels of substitution and reduction of caloric value, at the expense of energy from fat, especially at higher reduction levels (40 and 60%). The fat replacement at 40 and 60% had a caloric value decrease by 48 kcal per 100 g compared to the control and respectively the energy at the expense of the fat was 37.9 and 25.7% (reduction by 71.3 and 48.3%). Sensory evaluation demonstrated good acceptability for all the products with slight prevail for the samples with 40% followed closer by those with 20% fat replacement. Hence, chia gel proved to be a good alternative for fat substitution in baking goods recipes while preserving the quality and sensory parameters aiming to produce healthier foods.

Open access