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Abstract

Residues in animal feeds and foods of animal origin have been important safety issue concerning both human and animal health. A multiresidue method for determination of eight mycotoxins and ten antibiotics was developed and validated in animal feeds by using QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction followed by UHPLC-MS/MS. Optimisation of UHPLC-MS/MS parameters was performed to achieve good separation and resolution. The method was validated according to the European Commission Decision 2002/657/EC. Matrix matched calibration curves showed good r 2 (≥0.995) values, and limit of quantification (LOQ) values varied between 1.2 and 5.2 μg kg−1. Average recoveries ranged from 60 to 102% with relative standard deviations of 2.2 and 15.6% for all type of feed samples except for tetracyclines, lincomycin, tylosin, ochratoxin A, and fumonisin (B1 and B2).

Open access

Abstract

The probiotic and technological potentials of lactic acid bacteria originating from human milk are becoming a remarkable research area. In the present study, Limosilactobacillus vaginalis MA-10 isolated from human milk was investigated in vitro for its probiotic and technological aspects. According to the results obtained in the study, MA-10 strain exhibited non-haemolytic activity and various degrees of sensitivity to most of the tested antibiotics. The strain showed good resistance to the gastrointestinal system and maintained its viability under these conditions. Its antimicrobial activity against human or clinical bacterial and fungal microorganisms and fish bacteria was determined in the range of 2.38–11.22 mm. The MA-10 strain was able to assimilate cholesterol ranging from 31.42 to 82.30%. The strain showed 9.34% ferrous-ion chelating and 32% DPPH free radical scavenging activities. These initial results from the present study confirm that L. vaginalis MA-10 may be a new source with appropriated probiotic and technological traits for various industries, and further in vivo assays.Due to the limited number of studies on L. vaginalis strains originated from human breast milk in the literature, the data obtained in this study are thought to be important for revealing the basic probiotic properties of the strain.

Open access

Abstract

This study assesses consumers' preference for food from social media on a sample of 510 respondents from the Eastern region of Saudi Arabia using the Best-Worst Scaling method. The findings of the study conclude that unhealthy and nutrient-poor food items are more preferred than healthy and nutrient-rich food items. The study recommends that the food and drug authority should intervene to increase consumers' awareness about the effect of unhealthy food items by creating social media accounts to warn consumers about the health outcomes of consuming certain unhealthy foods marketed through social media platforms.

Open access
Acta Alimentaria
Authors: Sz. Gy. Szerencsés, S. Beszédes, Zs. László, G. Veréb, D. Szalay, Zs. Hovorkáné Horváth, C. Hodúr, G. Rákhely, and Sz. Kertész

Abstract

In this study, statistical analysis was performed to investigate the influence of operational parameters based on experimental results. The research aimed to know whether a long-term discontinuous module vibration operation is possible without adversely affecting filtration efficiency. Polymer membranes were compared by surface characteristics with contact angle measurements and selected for further membrane filtration experiments for dairy wastewater treatment. The effect of the main operational parameters, membrane module vibration amplitude (A vibr.) and transmembrane pressure (TMP), was investigated using a vibratory shear enhanced processing (VSEP) module with ultrafiltration (UF) and nanofiltration (NF) membranes. Components of the permeates, including chemical oxygen demand (COD), were measured, and membrane rejections were calculated to compare with threshold limit values. The results suggest that proper combination of A vibr. and TMP could mitigate membrane fouling. However, discontinuous module vibration resulted in more clogged membrane with lower fluxes, but slightly higher rejections. We conclude that investigating the significance of operational parameters is necessary for a wider, more energy and environment-friendly application in wastewater treatment.

Open access

Abstract

The presented research aimed to confirm that the differences in the lipid peroxidation of three maize (Zea mays L.) hybrids with different genotypes and maturity are due to different nitrogen levels, which was observed based on the amount of malondialdehyde (MDA) measured in the leaves at the main phenological stages of plants. The experiments were performed in a multi-factorial long term fertilisation field trial. In the study, phosphorus and potassium were constantly provided at the optimal level for the plants. The phosphorus and potassium fertilisation were applied in autumn. However, N levels varied from 0 to 300 kg ha−1. Sampling was done at different growth stages 5 times during the growing season (4 leaves, 6 leaves, 8 leaves, 14 leaves, silking). The 300 kg ha−1 N (dose 3) resulted in a significant increase in lipid peroxidation (MDA level), but not a statistically significant difference between the control (dose 1) and the 120 kg ha−1 (dose 2) N doses. The H1 hybrid had the lowest level of lipid peroxidation at the first sampling date. High volume nitrogen fertilisation (dose 3: 300 kg ha−1) increased lipid peroxidation in the hybrids. Averaging the values obtained for the same hybrid at the different sampling times, the medium (dose 2) 120 kg ha−1 N treatment had no significant effect on the lipid peroxidation of the hybrids compared to the values of the control plants. Based on the lipid peroxidation response of the hybrids to N treatment, the exact N dose inflection point can be determined to make the fertiliser utilisation of plants more efficient. Based on our results, we found that inadequate, low (120 kg ha−1) or high (300 kg ha−1) nitrogen fertilisation could affect the MDA levels of plants, thereby affecting the functioning of the lipid peroxidation mechanism.

Open access

Abstract

The enzymatic conversion of sucrose to fructo-oligosaccharides (FOS) catalyzed by Pectinex Ultra SP-L, a commercial enzyme preparation from Aspergillus aculeatus, under free condition was studied. A mathematical analysis of the transfructosylation reactions was carried out to estimate the dynamic and steady-state performance of an enzyme membrane reactor (EMR) and to compare the continuous production scheme with the traditional batch process realized in stirred-tank reactor (STR). Kinetic parameters were identified simultaneously from a series of progress curves obtained from STR and EMR experimental runs. Model estimates appeared to fit well to experimental observations under the studied reaction conditions. Although conventional batch reactor outperforms EMR in terms of conversion, EMR compares favorably regarding productivity. The on-site industrial implementation of this technology might be attractive for food manufacturers aiming at utilizing a value-added sweetener mixture with prebiotic properties.

Open access
Progress in Agricultural Engineering Sciences
Authors: V. Parrag, Z. Gillay, Z. Kovács, A. Zitek, K. Böhm, B. Hinterstoisser, R. Krska, M. Sulyok, J. Felföldi, F. Firtha, and L. Baranyai

Abstract

One of the most important food safety issues is the detection of mycotoxins, the ubiquitous, natural contaminants in cereals. Hyperspectral imaging (HSI) is a new method in food science, it can be used to predict non-destructively the changes in composition and distribution of compounds. That is why, in the last decade, the potential of HSI has been evaluated in many fields of food science, including mycotoxin research.

The aim of the recent study was to test the feasibility of HSI for the differentiation according to the toxin content of cornmeal samples inoculated with Fusarium graminearum, Fusarium verticillioides and Fusarium culmorum and samples with natural levels of mycotoxins. Samples were measured in the near infrared wavelength range of 900–1,700 nm and mean spectra of selected regions of interest of each image were pre-treated using Savitzky-Golay smoothing and standard normal variate (SNV) method. On the spectra, partial least squares discriminant analysis (PLS-DA) was carried out according to the level of contamination. Partial least squares regression (PLSR) method was used to predict deoxynivalenol (DON) content of samples and the cumulative toxin content: the sum of fumonisins (FB1, FB2) and DON content of samples. Based on the promising results of the study, HSI has the potential to be used as a preliminary testing method for mycotoxin content in feed materials.

Open access

Plant nutrition significantly influences yield and fruit quality in fruit orchards. In this three-year study (2016–2018), different fertilizer treatments were compared in an intensive sweet cherry orchard. Trees of cultivar ‘Carmen’ were grafted on Prunus mahaleb ‘Cema’ rootstock, and were trained to free spindle. For NP, NPK and NPKMg treatments, yield ranged between 11.8 and 16.6 kg/tree in the three years, while the yield was 9.1 kg/tree on the control trees. Crop load (fruit amount calculated to the trunk thickness) was 151–166 g cm-2 for fertilized trees, while it was 120 g cm-2 on the untreated trees. Fruit sizes of fertilized trees reached 30 mm in 2018, while the fruit sizes of control trees were smaller with 2.5 mm. Water-soluble dry matter content (%) of the fertilized trees was lower in 2016 and 2017, but higher in 2018 compared to the control plots. In 2017 and 2018, fertilizer treatments resulted in an increase of the content of phosphorus (16–70%), potassium (4–22%) and magnesium (12–43%) in the fruits compared to control plots.

Open access
Agrokémia és Talajtan
Authors: Kelemen Bettina, Füzy Anna, Cseresnyés Imre, Parádi István, Kovács Ramóna, Rajkai Kálmán, and Takács Tünde

The effects of cadmium (Cd) stress and arbuscular mycorrhizal fungus (AMF) inoculation were investigated in wheat [Triticum aestivum L. cv. TC-33] under controlled conditions. The experiments aimed to reveal what stress responses belong to the different levels of Cd load in the growth medium (0; 1; 2,5 and 5 mg Cd kg-1 substrate). To detect the effect of Cd stress, we compared plant physiological and growth indicators measured with both in situ and destructive methods. Electrical capacitance (CR) was evaluated during the experiments as a method to indicate stress responses through of Cd-induced root system changes.

During the growth period, the photosynthetic activity (Fv/Fm), the chlorophyll content index (CCI) of the leaves, and the CR of the root-soil system were monitored in situ. After harvest, the membrane stability index (MSI), the cadmium and phosphorus concentrations of the plants, the root dry mass (RDM), the shoot dry mass (SDM) and the leaf area (LA) were measured. The root colonization of AM fungi was estimated by microscopic examination. Data matrices were evaluated with principal component analysis (PCA) which had been proved to be a good statistical method to the sensitivity between measurement methods.

Taking all parameters into account in the PCA, a complete separation was found between the contaminated and non-contaminated variants along the main component PC1. The measured values of the Cd1 treatment sometimes overlapped with that of control plants, but differed from that of the Cd2 and Cd3 doses. The parameters well reflected that AMF inoculation alleviated the stress caused by Cd. PCA shows a visible effect of AM, but the separation between mycorrhizal and non-mycorrhizal plants is weaker than that between Cd contaminated and non-treated ones. The Cd stress significantly decreased the Fv/Fm, CCI, CR, SDM, RDM and LA. The CR and growth parameters proved to be the best indicators to characterize the Cd phytotoxicity in the TC-33 wheat cultivar.

Open access