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Scope of the study was to find more effective N fertilisation doses and applications to reach not only higher quantity but better quality grains as well as to be able to help preserving the continuity of feed and food quality improvement, since wheat is one of the most consumed crops all over the world.

Samples of winter wheat (Triticum aestivum L.) varieties harvested from the experimental field of the Szent István University in two consecutive crop seasons had been examined in the laboratory of the Crop Production Institute. Effects of nitrogen (N) application on the performance of grain protein were tested. Five high quality winter wheat varieties were studied regarding grain quality traits affected by applying undivided and split doses of N. The evaluated samples show that increasing doses of N topdressing and increasing time of application have beneficial effects on the yield and the value of protein content. Wheat grain protein value ranged between 9.9% of the untreated Mv Karéj and Alföld, where the 120+40 kg ha-1 N was applied resulting in the highest value of 16.0%. Similarly, the gluten values among untreated and N applied plots were in a wide range. Mv Karéj had the lowest wheat gluten value on untreated plot with 18.4% and Alfold had the highest value with 36.8% on the plot where the 120+40 kg ha-1 N was applied. There were no significant changes recorded on test weight and thousand kernel weight. In the case of baking quality, there were significant differences between varieties. The best records were obtained in the case of Mv Toborzö followed by Mv Karéj.

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Medium chain fatty acids are candidates of partial sulphur dioxide replacement in wine, as a solution to the growing consumer concerns about chemical additives. In botrytised sweet wine specialties, large amount of sulphur dioxide addition is one of the effective practices to stop alcoholic fermentation. Increasing medium chain fatty acid levels up to 80 mg l-1 was tested as a sole inhibitor on solid agar surface. S. bacillaris seemed to be the most sensitive, S. cerevsisiae and S. bayanus were more tolerant, while Z. bailii showed the highest tolerance. Then, increasing medium chain fatty acid levels up to 40 mg l-1 combined with 100 mg l-1 sulphur dioxide was introduced into a Tokaj Essence under refermentation. After 56 days, the highest dosage had pronounced effect on the yeast population, but the refermentation was not inhibited completely. Medium chain fatty acids have varying inhibitory effect on botrytised wine-related yeasts, moreover, it could be used effectively in media with high ethanol content, unlike Tokaj Essence.

Open access

The influences of dried Morchella conica powder (MCP) on quality and sensory properties of sucuks were determined. Sucuks were prepared by adding 0% (control), 1.5% MCP, 3% MCP, 0.02% butylated hydroxytoluene (BHT), and sodium nitrate/nitrite (0.01% NaNO 3 /0.005% NaNO 2 ) and lipid oxidation, colour, texture, and sensory features were analysed. Sucuks with the addition of MCP had much lower (P<0.05) peroxide values than with the addition of BHT and nitrate/ nitrite and the control samples. It was found that the L* and a* values of sucuks with the addition of 1.5% and 3.0% MCP decreased significantly (P<0.05) compared to sucuks with nitrate/nitrite and BHT addition and control samples during fermentation. Hardness and chewiness values decreased with the addition of MCP (P<0.05) during fermentation. The sucuks with MCP added at 1.5% and 3% showed the highest overall sensory acceptance. Thus, proper amount of dried MCP addition may be effective on enhancing sucuk quality properties.

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Acta Alimentaria
Authors: J.A. Pino, E. Sauri-Duch, O. Sosa-Moguel, C.A. Can-Cauich, V.M. Moo-Huchin and L. Cuevas-Glory

An aroma distillate with the odour note described as ‘fresh Habanero chilli pepper' was obtained from hydrodistillation of the fruit. GC-MS analysis of the volatile constituents from the aroma distillate allowed the identification of 100 compounds, most of them esters followed by aldehydes, alcohols, terpenes, ketones, and acids. Encapsulation process of the aroma distillate by spray drying was optimised using response surface methodology. Independent variables were inlet air temperature (150-200 °C) and carrier (maltodextrin 10 DE and gum arabic in 2:1 ratio) content (10-20% wb), while response variables were powder moisture and volatiles retention. Moisture content of the powder varied inversely proportional to the air temperature, while the volatile retention was directly related. Retention of volatiles in the powder increased when the carrier content increased, while this factor negatively affected moisture content. Based on the optimisation model of the response variables, the powder with the highest flavour quality was obtained with an air inlet temperature of 200 °C and 20% wb carrier content, with 4% moisture content and 88.6% volatiles retention.

Open access

The aim of the study was the identification and characterisation of coagulase-positive Staphylococcus bacteria obtained from food matrices by mass spectrometry and molecular methods. A total of 46 coagulase-positive Staphylococcus isolates were collected from different foodstuffs. The Staphylococcus isolates were identified by MALDI-TOF MS and confirmed by the presence and sequence analysis of the Staphylococcus protein A gene. Staphylococcal enterotoxin genes were also investigated by multiplex PCR. Based on the identification of strains by the MALDI-TOF MS technique and spa-typing, all strains were identified as Staphylococcus aureus. Based on their MS peak profiles, the isolates matched the spectra of three S. aureus reference strains in the Bruker MALDI Biotyper database, with identification scores higher than 1.999 in the case of all 46 (100%) isolates. The isolates showed great genetic variability. Twenty spa types were identified, from which most lineages are capable of colonizing humans. Fifty percent of the strains harboured at least one of four enterotoxin genes (seg, seh, sei, and ser), but none of the classical enterotoxin genes could be detected.

Open access

The surplus of waste glycerol, by-product of the biodiesel production process, is available at the global market. Some species of the genera Streptomyces have the ability to assimilate glycerol and convert it into valuable metabolic products. In the present study, the ability of Streptomyces hygroscopicus to assimilate waste glycerol and convert it into metabolic compounds with antifungal activity against four phytopathogenic fungi obtained from apple fruit samples expressing rot symptoms, was investigated. Production of antifungal metabolites by S. hygroscopicus was carried out in 3 l stirred tank bioreactor through 7 days. Fermentation was carried out at 27 °C with aeration rate of 1.5 vvm and agitation rate of 100 r.p.m. The aim of this work was to analyse bioprocess parameters and to determine at which stage of bioprocess the production of antifungal metabolites occurs. Activity of the cultivation liquid on two isolates of Alternaria alternata and two isolates of Fusarium avenaceum were determined every 12 h using in vitro well diffusion method. It was found that the maximum production of antifungal metabolites occurred at 108 hour of cultivation. Formed inhibition zones have shown that the produced antifungal metabolites have high efficacy on tested phytopathogenic fungi (inhibition zone diameter higher than 35 mm for all test organisms).

Open access

Due to the shift in consumer behaviour, the proportion of well informed, conscious consumers has been growing steadily, and functional foods with their capacity to protect health have been gaining more and more ground. To achieve market success in the field of functional foods, producers should be able to communicate information effectively concerning health issues and their newly developed product should indeed meet consumer expectations. The aim of our study was to identify and define the components of the dimensions of consumer attitudes in Hungary together with the barriers and motivators of health behaviour. Our research also examined how these factors influence consumer willingness to consume functional foods. Our surveys were carried out in focus groups of health-conscious (n=8) and not health-conscious (n=8) consumers. Our findings confirmed the adequacy of the international dual model, regarding the attitudes of Hungarian consumers towards functional food. Moreover, we also explored the most popular health food categories and sources of information on nutrition.

Open access

Indiscriminate use of antibiotics in apicultural practices may lead to contamination of otherwise healthy and naturally produced honey. Contamination not only affects honey quality but also pose significant health risks to consumers. In this context, one hundred raw honey samples from India were analysed for presence of antibiotic residues. For determination of oxytetracycline and erythromycin, high performance liquid chromatography and for chloramphenicol, enzyme immunoassay based validated procedures were used. Oxytetracycline and erythromycin with concentrations above maximum tolerance limits were detected in 24% and 2% samples, respectively. None of the samples contained chloramphenicol residues. Although, total dietary intake of detected antibiotics through honey was found to be <1% of their acceptable daily intake values, the presence of antibiotics in honey is an alarming health concern for people following customary honey feeding. The outcomes underline the need of inter-sectoral approaches to create awareness among beekeepers regarding health risks associated with residues of antibiotics in honey and merits of approved apicultural practices. Therefore, to meet global food safety requirements, continual residue monitoring schemes along with enlightenment of beekeepers on scientific beehive management and risks associated with incautious apicultural practices are of vital importance.

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Abstract

One of the major public health concerns today is bacterial infection-associated diseases. Traditional antibacterial therapies are becoming less efficient because frequent and inadequate use of antibiotics has caused mutations in bacteria that led to many antibiotic-resistant bacterial strains. It is, therefore, crucial to develop novel antibacterial materials and strategies that will successfully combat both gram-positive and gram-negative bacteria. In the present study, we will demonstrate a simple and efficient method for bacteria capture and elimination through photothermal ablation. The developed material consists of a flexible Kapton substrate, coated with reduced graphene oxide-chitosan (rGO-CS) thin films. Reduced graphene oxide has strong absorption in the near-infrared (NIR) region, while chitosan has the ability to bind bacteria through electrostatic interactions. The K/rGO-CS device proved to capture and efficiently eradicate both planktonic Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria after 10 min of NIR (980 nm) irradiation.

Open access

Abstract

In order to modify both chemical and electrical properties of graphene-based nanomaterials, we conducted the chemical modification of graphene oxide (GO) and graphene quantum dots (GQDs). The reaction of the reduction with nascent hydrogen was conducted on both materials. The structure and morphology of produced chemically reduced GO and GQDs were analyzed. While the chemical composition of both GQD and GO changed significantly, GO showed also significant changes in morphology as opposite to GQDs where were morphological changes were not observed.

Open access