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Abstract

Hungarian fruit vinegars were characterised in terms of physicochemical attributes (total polyphenol content, antioxidant characteristics/FRAP, CUPRAC, ABTS/, ascorbic acid content, pH, total soluble solids), sensory profiles, and antimicrobial properties.

Both compositional and sensory profiles showed distinct patterns depending on the type of vinegar (Tokaj wine, balsamic or apple) and the additional fruit used. Balsamic vinegars maturated on rosehip, sea buckthorn, and raspberry showed outstanding antioxidant performances. Rosehip, raspberry, and quince vinegars, as well as vinegars produced from Tokaji aszú and balsamic apple obtained high scores for fruity and sweet notes.

Antimicrobial activities were tested on Gram-negative and Gram-positive organisms, including probiotic bacteria. Generally, only weak activities were obtained, which was attributed to the natural sugar content of the samples, depending on the type of the vinegar and the fruit. Similar results, but more pronounced bacterial growth inhibitions were obtained for probiotic strains, however, some probiotic strains were resistant to at least two of the vinegars. Based on these, balsamic apple, raspberry, rosehip, quince, and sea buckthorn may qualify as potential functional components of probiotic preparations containing some of the strains tested.

Open access

Abstract

Aroma components of wines play an important role in the sensory quality of wines. In our paper we investigate the effect of commercially available yeast nutrients under different fermentation parameters. Caproic acid, caprylic acid, capric acid, and different fatty acid esters were used as markers of the alcoholic fermentation process. The optimal temperature for the fermentation of different white wines was at 15–16 °C, in the case of examined wines lower concentrations of fatty acids and fatty acid esters were found at this temperature. At 25–26 °C fermentation temperature very high concentrations of fatty acids and fatty acid esters were detected. Applying different nitrogen-containing wine additives we managed to achieve better aroma profiles for white wines even using musts of lower quality.

Open access
Agrokémia és Talajtan
Authors: Birkás Márta, Balla István, Gyuricza Csaba, Kende Zoltán, Kovács Gergő Péter, and Percze Attila

A magyar talajművelésben a kezdetektől az 1900-as évek közepéig a hagyományos szántásos rendszerek domináltak. Az ekék tökéletesedése révén a mélyebb szántások hozzájárultak a talajminőség romlásához.

Az 1900-as évek első évtizedeiben a külföldön kidolgozott művelési módszerek még kevesek érdeklődését keltették fel, azonban a szántásnál kedvezőbb körülmények létrehozása érdemi figyelmet keltett.

Az 1970-es évektől a talajvédő művelés Magyarországon is kedvező fogadtatásra talált. Kísérletekkel igazolódott, hogy a direktvetés előnyei – folyamatosság esetén – a hatodik-hetedik évtől észlelhetők. A mulcshagyó művelés kultivátor alkalmazása esetén rövidebb idő alatt nyújtotta a várt talajvédelmi előnyöket, ennek tudható be a gyorsabb terjedése. A kultivátoros művelés értékét a felszínvédő mulcshagyás, a talajminőség megóvás és a biológiailag aktív talaj erősítette meg.

Az időjáráshoz kapcsolható szélsőségek megjelenése az 1980-as évektől újabb művelési megoldások felé fordították a figyelmet. A talajlazítás a vízbefogadás és tárolás, a mulcshagyás, valamint a növények mélyebb gyökerezése révén került a korábbinál szélesebb körű alkalmazásra. A sávos művelési rendszer a nemzetközileg bizonyított eredmények hátterével számos magyar gazdálkodónál is sikeressé vált.

A magyar talajművelés előrehaladásában a talajközpontú szemlélet kiszélesedése, a növényközpontú szemlélet felváltása révén eredményezett kedvező változásokat a talajállapot javulásában.

Tekintettel a talajok sokféleségére és a talajállapot eltéréseire, jelenleg a termőhelyhez, talajhoz adaptált művelési rendszer alkalmazása látszik eredményesnek. Az időjárási szélsőségek fokozódása általában és adott termőhelyen is rangsorba állítja a lehetséges módszereket. A korábban jónak tartott megoldások, beleértve a szántást, ugyanis már egyre kevésbé biztonságosak.

A talajkímélő művelés iránti érdeklődés közel százhúsz évre tekint vissza Magyarországon. Sajátos, de az előrehaladás és a visszatartás tényezői a talajművelésben párhuzamosan jelentek meg az eltelt évek alatt. A művelési előrehaladást visszafogó tényezők között a sok évtized óta fennálló hiedelmek voltak a leginkább hátráltatók, mivel figyelmen kívül maradt a talajvédelem, továbbá a klímaváltozással kapcsolatos veszélyek enyhítésének igénye. Az előrehaladást a talajvédelem felvállalása, a gazdálkodási színvonal emelésének esélye és a klímakár csökkentés kényszere mozdította elő. Az előrehaladást alátámasztó tényezők között legfontosabbak a talajállapot tartós javulása és a klíma eredetű károk enyhítése, továbbá a termés biztonság megtartása és javulása.

Open access

Abstract

As the world is facing numerous global ecological issues at once, the question arises of what will help mitigate and solve contemporary matters related to resource management or climate change without devastating the economies. Fortunately, the widespread application of the circular economy would help countries worldwide simultaneously ensure economic growth without significant environmental deterioration, essentially decoupling the two factors. While Hungary’s contribution to environmental problems is not significant in absolute terms, the economic sector’s circular transition could help the country decrease its impact in relative terms and pave the path for a green economy. Nevertheless, companies, especially SMEs, tend to struggle the most with the initial phases of the shift thus it is crucial to assess the factors that prevent and support their transition.

Open access

Abstract

Potential functional food bakery products were developed and characterized based on White Lupin (Lupinus albus cv. Nelly) flour. Analytical properties of the seeds resemble to previously described Lupinus species, with significantly high protein content (45%). The high protein and dietetic fiber content of the seeds makes Lupin flour suitable to develop potential functional food products with high nutritional values. Results of the development of sweet biscuits and salty crackers enriched with Lupin flour are presented. Sensory evaluation of the bakery products was carried out by 15 panelists using the nine points hedonic scale. Heat stability of White Lupin proteins were investigated by gel-electrophoretic analysis, White Lupin proteins are quite stable at 140°C, after 35 min heating the biscuits still contain 69% of the original amount of proteins. Baking conditions were optimized also based on gel-electrophoretic experiments, the optimal baking time was 30 min at 140°C. Gluten-free Lupin-based biscuits and crackers were produced by completely omitting wheat flour from the recipes.

Open access

Abstract

Wastewater issues became a complex challenge in the world. There are several methods in wastewater treatment, such as chemical, physical, biological, and the combination of each method. However, each process has advantages and disadvantages. The physicochemical methods are common methods used in wastewater treatment, such as adsorption and coagulation. Adsorption and coagulation are excellent methods to remove pollutants. The adsorption process is greatly influenced by pH, adsorbent dose, temperature, and contact time. Coagulant dose, settling time, and pH are the main factors in the coagulation process. Chemical material as an adsorbent and coagulant has been studied in previous research, but recently, to substitution chemical materials is a challenging subject. Natural substances are potential new materials in wastewater treatment and became popular due to their efficiency and environment friendly characteristics. This review investigated the role of adsorption and coagulation in wastewater treatment and the utilization of natural materials as adsorbents and coagulants.

Open access

Abstract

Built elements and structures are a prominent component of our historic gardens, both in terms of function and artistic composition and garden scenery. The surveys of historic garden structures are important research tasks, which also underpins and validates restoration work.

In most cases, the neglected state of historic gardens and sites and the unavailable archival materials do not allow an authentic restoration of historic gardens to their original state. Nevertheless, there is a real need to reconstruct our historic gardens, based not only on historical authenticity but also on a systematic reinterpretation of the relationship between society and landscape.

The objective of this article is to present a general methodology for renewal of historic gardens through examples of specific garden reconstructions. The case studies are the authors' own design works, which demonstrate the application of different design approaches, highlighting details of the reconstruction of specific built garden elements.

Open access

Abstracts

Zygosaccharomyces species are among the most problematic food spoilage yeasts. The two most infamous species are Zygosaccharomyces balii and Zygosaccharomyces rouxii, although they may also take a positive role during the production of some fermented foods. DNA sequence based yeast identification aided by freely available reference databases of barcoding DNA sequences has boosted the description rate of novel yeast species in the last two decades. The genus Zygosaccharomyces has been considerably expanded as well. Especially the number of the extremely osmotolerant Zygosaccharomyces species, related to Z. rouxii and regularly found in high-sugar foods, has enlarged. A brief account of recent developments in the taxonomy and biodiversity of this important food associated genus is given in this review.

Open access
Acta Alimentaria
Authors: M. Mardani, L. Somogyi, I. Szedljak, I. Prauda, J. Farmani, and K. Badakné Kerti

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