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Abstract

The local food concept is analysed from a supply chain perspective and its positive environmental effects. Revitalised local economies, reduced greenhouse emissions, preservation of farmland and rural lifestyles associated with local products impacts consumer preferences by reflecting a positive attitude toward locally grown products. In addition, the health benefits of local products are more frequently evoked by consumers than those of organic-local products. However, the labelling of such products is used despite consumers and/or producers not being clear about the attributes conferred by the product locality. In this context, this paper aims to clarify the perception of Albanian consumers regarding local fruit and vegetables. The results show that the positive WTP for local food relies on the consumer concern about health and environmental issues. In the case of Albanian consumers, this is driven more by health, taste and environment. Surprisingly, environmental concern exceeds other attributes like price and origin. In this case, environmental issue overlaps health, and it is used as a surrogate indicator for the latter. This is due to the lack of trust in public authorities that fail to assure an efficient quality control process in the agriculture and food sector.

Open access

Abstract

In the last decade, bread consumption was decreasing in Hungary (from 44.5 kg to 34.4 kg/capita). Our aim is to identify the factors influencing the consumption of different bread and bakery products, using the Food Choice Questionnaire (FCQ).

FCQ is frequently used to explore factors (e.g., price, packaging, etc.) influencing the purchase of different food products. The adapted version of the FCQ for breads and bakery products is not yet available in Hungarian language. Word association (WA) and triangulation methods are usually used in the adaptation process.

Due to COVID-19, WA method was performed with a newly developed application presenting six photos of breads. This was completed by 193 participants. Responses were analysed using a categorizing triangulation technique, based on which the FCQ was modified.

In this study, we present the implementation and the results of the digitalized WA method and its use in the adaptation process of the FCQ.

Open access

Abstract

A sensitive and rapid method using HPLC-MS/MS was developed for the determination of eight glucocorticoids residues in chicken muscle simultaneously by Turbo Flow. The eight glucocorticoids were prednisone, prednisolone, hydrocortisone, methylprednisolone, dexamethasone, betamethasone, beclomethasone and fludrocortisones. Samples were extracted with ethyl acetate and on-line cleaned up through a Turbo Flow solid-phase extraction column without time-consuming pretreatment before HPLC-MS/MS analysis. Sample pretreatment conditions, Turbo Flow conditions and mass spectral parameters were optimized and obtained eight glucocorticoids calibration curves. These curves showed good linearity over the concentration from 0.2 μg/kg to 50 μg/kg with an average recovery from 71.63% to 117.36%. This method could be applied on real samples and provided simple, rapid, sensitive and highly selective analysis, which made it feasible to be adopted in food inspection organizations or carry out quantitative analysis for other banned substance.

Open access

Abstract

The quality of pesticide formulations has an impact on the crop safety, environment and human health. Therefore, the development of new analytical methods for the determination of active substances in pesticide formulations in order to control their quality, as well as, their residues in food samples in order to ensure food safety, is always welcome. A new, simple, precise and accurate normal-phase high-performance liquid chromatography (NP-HPLC) method for determination of an active ingredient malathion in the commercial emulsifiable concentrate pesticide product has been developed and validated. The analysis was carried out on a LiChrosorb CN (250 x 4 mm, 5 μm) analytical column using isocratic elution with mobile phase consisted of n-hexane and dichloromethane (80/20, v/v), flow rate of 1 mL/min, constant column temperature at 25 °C and ultraviolet diode-array detection at 220 nm. The obtained values for multiple correlation coefficients (R 2 ≥ 0.9990), relative standard deviation of retention times, peak areas and heights (RSD ≤ 1.14%), recoveries ranged from 98.97 to 101.62%, revealed that the developed method has a satisfactory linearity, precision and accuracy. Also, the developed method was successfully applied for determination of malathion residues in apple juice samples, after preliminary sample preparation using solid-phase extraction. Specificity, selectivity, linearity, matrix effect, precision and accuracy were tested in order to validation of this method. The obtained results were in acceptable ranges and indicated that the developed method is suitable for routine determination of malathion in the pesticide formulation, as well as for determination of malathion residues in apple juice samples. The run time of HPLC analysis was about 6 min.

Open access
Progress in Agricultural Engineering Sciences
Authors: Karina Ilona Hidas, Csaba Németh, Lien Phuong Le Nguyen, Anna Visy, Adrienn Tóth, László Friedrich, and Ildikó Csilla Nyulas-Zeke

Abstract

Freezing can enhance the storage time of liquid egg products, but egg yolk undergoes an irreversible textural and structural change when it is cooled to –6 °C. In this study, the effects of different salt concentrations on the physical properties of frozen-thawed egg yolk were investigated.

The pasteurised liquid egg yolk (LEY) was treated with 4, 5, and 6% of NaCl before freezing and it was stored at –18 °C for 4 weeks. The colour, pH, and rheological characteristics (firmness, consistency, cohesiveness, and index of viscosity) of yolk samples were evaluated before and after freezing.

Salt treatment resulted in preventing gelation, with decreasing firmness, consistency and viscosity compared to control samples. The pH of all yolk samples increased during frozen storage. The lightness value decreased in treated samples and increased in the control sample after freezing.

The results indicated that the applied salt concentrations could inhibit protein aggregation of LEY induced by freezing during the storage period. At least 5% salt concentration could reduce effectively the changes in rheological properties.

Open access

Abstract

Tectorigenin, tectoridin, irigenin, and iridin are the four most predominant compounds present in She Gan. She Gan has been used in traditional Chinese medicine because of its anti-inflammatory, hepatoprotective, anti-tumor, antioxidant, phytoestrogen-like properties. In this paper, a UPLC-MS/MS method was developed to measure the pharmacokinetics of tectorigenin, tectoridin, irigenin, iridin after intravenous administration in mice. A UPLC BEH C18 (50 mm × 2.1 mm, 1.7 μm particle size) chromatographic column was utilized for separation of the four target analytes and internal standard (IS), and the analysis of blood plasma samples; the mobile phase consisted of an acetonitrile-water (w/0.1% formic acid) gradient elution. Electron spray ionization (ESI) positive-ion mode and multiple reaction monitoring (MRM) mode was used for quantitative analysis of the analytes and internal standard. The four compounds were administered intravenously (sublingual) at doses of 5 mg/kg. After blood sampling, samples were processed and then analyzed by UPLC-MS/MS. The linearity of the method was robust over the concentration range of 2–5,000 ng/mL. The intra-day precision of the analysis was within 15%, the inter-day precision was within 12%, and the accuracy was between 92% and 110%. The recoveries were 65–68%, and the matrix effect was 93–109%. The established UPLC-MS/MS detection method was then successfully applied to study the pharmacokinetics of tectorigenin, tectoridin, irigenin, iridin in mice.

Open access
Restricted access
Progress in Agricultural Engineering Sciences
Authors: Dávid Nagy, Viktória Zsom-Muha, Csaba Németh, and József Felföldi

Abstract

The aim of this study was to determine the effect of ultrasound treatment on foaming properties of egg white. The samples were sonicated at 20/40 kHz and 180/300 W equipment power (3.7/6.9 W absorbed power) for 30, 45 and 60 minutes. Foam capacity had been increased by 25% due to sonication at 40 kHz and 6.9 W absorbed power for 60 minutes. This phenomenon may be caused by the homogenization effect of ultrasound and protein exposure of hydrophobic groups that improve the adsorption of protein onto the air/water interfacial molecules. It is found that frequency and duration of the treatment have no significant impact on the changes in foam capacity, only the absorbed power. On the other hand, foam stability had been decreased during the ultrasonic treatment. We can assume that sonication decreases the potential difference between the dispersed particles and the dispersion medium and this may be the cause of the collapse of the foam structure due to ultrasound treatment. In this case frequency, treatment time, and the absorbed power had a significant effect on the stability.

Open access

Abstract

A fast LC-APCI-MS/MS screening/confirmation method was developed and validated for trace analyses of 18 analytes which are explosives and organic gun shot residues including the challenging ones with diverse ionization conditions, in soil and on hands. (+) and (−) ionization modes were used after a single-step, low-volume solvent extraction procedure developed using methanol. Tape-lifting, stub, alcohol wipes, cotton bud were compared for collecting the residues from hands of a shooter. Tape-lifting and stub gave the highest recoveries and tape-lifting was chosen. Gradient elution system using ammonium chloride:methanol was developed. Whole procedure lasted approximately 30 min, was validated in both matrices, applied to real samples as post-blast residues, smokeless powder and the hands of a shooter, after shooting. Most of the recoveries were >80% and since all the precisions were <15%, quantitation was possible for all. Limit of Detection (LOD) and Limit of Quantification (LOQ) values were: 0.2–54.1 and 0.3–190.0 ngg−1 in soil, and 0.2–132.3 and 1.1–355.0 ngg−1 in tape-lift.

Open access