查看更多>>摘要：The fruits are seasonal and usually available at a particular season of the year. The post-harvest processes are applied to ensure that the products are consumed throughout the year. Drying is one of the most important postharvest processes, and the hot air method is generally used. In this study, 'Ankara' pear samples were dried by combining the electrohydrodynamic method, a promising drying technology, with hot air. This study aims to investigate the effects of different air velocity and voltage values on drying time, color, rehydration capacity, and microstructure. In addition, ten mathematical drying models were applied to the experimental results of the drying processes to obtain the model that best explains the drying curves. Two different air velocities (1.5 and 2.5 m/s) and four different voltage values (15, 20, 25, and 30 kV) were used for the drying processes. The process of drying pear products in the shortest time (80 min) was in the application of 30 kV-2.5 m/s. The models that best explain the drying curves of 'Ankara' pear were found to be the Logarithmic and Midilli et al. models. While the highest L* value was observed in the fresh product, the closest value to this value was observed in 15 kV-1.5 m/s applications. Rehydration capacity values of pear samples dried at high voltage values (25 and 30 kV) increased with increasing air velocity. The EHD-hot air method used in this study can be an alternative to conventional drying and can be a viable method in the drying industry by determining the appropriate air velocity and voltage value in order to provide better quality products in a short time.
查看更多>>摘要：In this study, a portable and quantitative immunochromatographic assay (ICA) was developed with a smartphone-based detection device as readout. The carboxyl group coated Fe3O4 nanoparticles (MNPs) were synthesized by a one pot method and used as the labeled tracer. Initially, zearalenone monoclonal antibody (ZEN mAb) and MNPs conjugates were prepared and applied as the detection probe. MNPs probe produced brown band at the detection zone of the ICA. To increase the sensitivity, MNPs probe were used to enrich ZEN from sample solution, a portable detection device was designed and a user-friendly APP was self-written to quantify results. The cut-off value of the MNPs-ICA for ZEN in cereals was 2.5 mu g/kg. The detection limit and quantification limit were 0.06 and 0.13 mu g/kg, respectively. The recoveries ranged from 82.0 to 117.7%, with coefficient of variation from 1.3 to 10.6%. The parallel analysis results of 20 naturally contaminated cereal samples by LC-MS/MS showed that the proposed method has high accuracy. Moreover, the results of stability experiments revealed that the ICA products had a shelf life of up to 6 months. Although the feasibility is demonstrated using ZEN as a model analyte, this approach can be easily developed to be a universal analysis system and applied to detection of a wide variety of small molecule hazard factor. This study proposed a qualitative and quantitative analysis device for the food safety analysis.
查看更多>>摘要：This study was dedicated to apply biological treatment using Lactobacillus (LAB) fermentation separately or in combination with an acoustic screening method for the prevention of mycotoxins in Fusarium spp. contaminated wheat-based products. Wheat samples of different contamination were treated separately using antimicrobial LAB strains (L. casei, L. plantarum, L. paracasei, and L. uvarum) and the changes on the level of deoxynivalenol (DON) and its conjugates such as 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), and DON-3-beta-D-glucoside (D3G)) were evaluated using UHPLC-QqQ-MS/MS and UHPLC-Orbitrap-HRMS. Additionally, an acoustic device was used to analyse DON in the wheat raw samples (without treatment). High linear correlations were obtained between HPLC results and the penetrated acoustic signal amplitude (Ap) for DON and D3G (R-2 = 0.85 and R-2 = 0.82, respectively). The results of fermentation demonstrated that bio-treatment of contaminated wheat was very effective for DON and masked toxin reduction in the media. Contaminated wheat-based products fermentation using L. uvarum allowed to reduce DON and D3G content in the media up to 75.0% and 84.1%, respectively, while the values of DON conjugates (3-ADON, 15-ADON) were reduced below LOD/ LOQ. Fusarium spp. contaminated wheat grains demonstrated different enzymatic profiles (amylolytic, xylanolytic, and proteolytic) which could be related with biological degradation of mycotoxins during fermentation. The amylolytic and xylanolytic activities of fungi correlated well with DON content (R-2 = 0.8235, R-2 = 0.8694, respectively) as well as with D3G (R-2 = 0.9314, R-2 = 0.9937, respectively). The findings of this study indicate that bio-treatment of contaminated wheat could efficiently reduce Fusarium mycotoxin levels below the LOD/LOQ in wheat-based products and improve the sustainability of grain production. However, before mycotoxin analysis LAB cells were not removed from the substrate and the results are focused on possible contaminants biodegradation. The acoustic technique could identify DON as well as D3G contamination in raw wheat grains and is a promising tool in the wheat grain processing chain.
查看更多>>摘要：The incidence of food poisoning remains high in Australia, particularly in Queensland and Western Australia. A recent safe food-handling media campaign was piloted in Busselton, Western Australia, and was found to lead to improvements in half of the safe food-handling behaviours targeted; however, safe food-handling knowledge did not increase. Consequently, the mechanisms underlying this behaviour change remain unknown. Therefore, the aim of the present study was to determine the mechanisms of behaviour change observed as a result of the pilot safe food-handling media campaign. Data from 117 participants who indicated whether or not they recalled the media campaign advertisements were analysed. Measures of perceived risk related to safe food-handling, safe food-handling habit, and safe food-handling behaviour were collected prior to and following the pilot safe food handling media campaign. Mediation analyses were conducted to determine if the media campaign advertisements predicted change in behaviour via change in perceived risk and habit. Results indicated that perceived risk and habit play an important role in safe food-handling behaviour change. These findings have implications for content development of future public health messages related to safe food-handling.
Tan, Hui RuChan, Li YanLee, Huei HongXu, Yong-Quan...
7页
查看更多>>摘要：Ambient mass spectrometry (AMS) is an emerging technique in food authenticity and traceability study due to the minimal sample preparation required and short analysis time. Herein, a non-targeted fingerprinting approach using an AMS technique, atmospheric solids analysis probe - mass spectrometry (ASAP-MS), was used to authenticate Chinese oolong teas. In the first part of the study, a total of 38 authentic samples from three main varieties - Guangdong Dancong, Taiwan Dongding, and Anxi Tieguanyin - were analysed and four discriminant analysis models were built using the fingerprint data from ASAP-MS. The principal component analysis-k nearest neighbour (PCA-kNN) model yielded the best classification outcome, where the classification accuracies of the training and validation sets were 100% and 92.6%, respectively. The second part of the study involved detecting possible adulteration of Anxi Tieguanyin, which is a high-value oolong tea under the register of protected geographical indication (PGI) of the European Union (EU). Adulteration of Anxi Tieguanyin was simulated by blending the authentic samples with 20-80% w/w of low-quality oolong teas. One-class modelling using datadriven soft independent modelling of class analogies (DD-SIMCA), with the Anxi Tieguanyin as the target class, was built using the fingerprint data of the authentic and adulterated samples. An excellent sensitivity of 100% and a high specificity of 98.1% were achieved, indicating that it is possible to detect substitution adulteration of Anxi Tieguanyin using ASAP-MS combined with one-class modelling. Overall, findings from this study exemplify the potential of ASAP-MS to be used for rapid, inexpensive, and high throughput classification of Chinese oolong tea varieties and screening for substitution adulteration of Anxi Tieguanyin oolong tea.
查看更多>>摘要：This study investigates the drying process of ginger slices using the microwave hot air rolling bed drying (MHARD) method, in terms of measuring drying kinetic change, moisture state and migration, dielectric characteristics, and color changes. The low-field nuclear magnetic resonance (LF-NMR) signal of free, immobilized, and bound water analysis indicates that during the drying of the sample, the drying rate followed a typical "rapid rise-steady-decline" trend in the "preliminary-constant rate-falling rate" stages, respectively. The LF-NMR result shows the content of free water (A23) in the ginger slices decreased gradually during the drying. Meanwhile, bound water (A21) content and immobilized water (A22) content firstly increased and subsequently decreased, because of the microwave and hot air, the movement of water molecules accelerated and the binding force weakened, and then bound water (A21) and immobilized water (A22) decreased. On the other hand, both dielectric constant (epsilon ' ) and loss factor (epsilon '') of the sample decreased gradually with the decrease in moisture content and logarithmic models were established to describe this correlation. In the preliminary drying stage, although increased microwave power led to a higher drying rate, it resulted in significant damage to the microstructure and compromised the color profile of the final dehydrated ginger slices. This research aims to discuss the mechanism of ginger slides dehydration using the MHARD technique to produce a final product with high quality.
Saraiva, Jorge A.Lemos, Alvaro T.Goodfellow, Brian J.Delgadillo, Ivonne...
11页
查看更多>>摘要：1H NMR spectroscopy was used to study the effect of hyperbaric storage (HS) on the chemical composition of high pressure pasteurized milk (HPP milk). A subsequent multivariate analysis (MVA) was applied to distinguish samples stored under different conditions. Three different pressure levels (50/75/100 MPa), at naturally variable uncontrolled room temperature (approximate to 20 degrees C), and up to 40 days of storage were compared with controls at atmospheric pressure and room temperature (AP/RT) or under refrigeration (RF). Only AP/RT samples presented spoilage compounds as lactate, methylamine and trimethylamine derived from microbial deterioration of milk. However, RF spectral profiles were closer to initial milk samples than the HS profiles, mainly in the aliphatic region which corresponds to an increase in soluble proteins for the HS samples. Additionally, MVA revealed higher levels of citrate, carnitine, lactose, and orotate in initial and RF samples, while HS samples had higher levels of acetate, N-acetylglucosamine, choline and galactose. In conclusion, although HS and RF samples were separated by MVA, there was no presence of microbial spoilage compounds in the spectra, being HS at RT an ecofriendlier alternative to preserve foods than traditional RF.
查看更多>>摘要：The epidemiological scenario of COVID-19, social distancing, and business restrictions has increased food preparation and consumption at home. Food mishandling at home can significantly raise the risk of foodborne diseases. This study investigates food-mishandling behavior predictors by applying the extended theory of planned behavior (TPB), with the addition of knowledge and risk perception, to households during the COVID-19 pandemic. One thousand and sixty-eight consumers (n = 1068) in Brazil participated in this study before the COVID-19 vaccination period. Data were collected using an online questionnaire with 40 questions and different anchors; they were analyzed using structural equation modeling. The following original TPB factors positively affected the intention to implement safe food-handling practices: attitude (p < 0.001), perceived behavioral control (p < 0.001), and subjective norms (p < 0.001). More robust effects of attitude and perceived behavioral control on intention were also observed. Although food-safety knowledge did not affect intention (p = 0.30), it positively affected the other TPB factors. Perceived risk positively affected all TPB factors. The results of this study support the usefulness of TPB and its extension, providing evidence that public-health crises can contribute to changes in food-safety-related consumer behavior.
查看更多>>摘要：Propiconazole is a widely used fungicide in agricultural production, but it poses risks to human health. Here, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on a monoclonal antibody (mAb) was established to detect propiconazole residues. Three haptens of propiconazole were designed and synthesized to prepare antigens. Ten mAbs were obtained using hapten B (5-(4-(2-((1H-1,2,4-triazol-1-yl)methyl)-4-propyl-1,3dioxolan-2-yl)-3-chlorophenyl) pentanoic acid). The ic-ELISA based on the combination of mAb 2G2E12 and hapten B-ovalbumin (coating antigen) showed the highest sensitivity. After optimization, the 50% inhibition concentration, limit of detection and linear range of the ic-ELISA were 2.33 mu g/L, 0.26 mu g/L and 0.26-21.28 mu g/ L, respectively. The cross-reactivities for the analogs of propiconazole were <1.9%. The average recoveries of the spiked samples were 75.7%-117.0% with relative standard deviations of <9.4%. The results of the ic-ELISA were consistent with those of gas chromatography-mass spectrometry in the analysis of blind samples. Therefore, we provide an alternative tool for the accurate and reliable determination of propiconazole.
查看更多>>摘要：Honey contains DNA of all organisms that directly or indirectly have been involved in its production, including the DNA of the honey bees. Therefore, using DNA extracted from honey, it is possible to analyse DNA markers useful to authenticate its entomological origin. In this study we developed an assay that can distinguish two mitotypes within the mitochondrial C lineage of Apis mellifera: the C1 mitotype, mainly carried by A. m. ligustica subspecies; the C2 mitotype, that is highly specific for the A. m. carnica subspecies. This method is based on Sanger sequencing of an informative regions of the honey bee mitochondrial DNA. A total of 255 honey samples were analysed. These samples included 157 commercial honey samples produced in three Italian regions of the North of Italy, in which A. m. ligustica is widely spread and 15 honey samples directly obtained from honeycombs. Fifteen of these commercial samples and all samples from honeycombs were known to be produced by A. m. ligustica. Other commercial honey samples, produced in Slovenia (n 38), Croatia (n. 22) and Serbia (n. 23), derived from A. m. carnica. All honey samples produced by A. m. ligustica had only the C1 mitotype whereas all honey samples produced by A. m. carnica had the C2 mitotype. C1 was the most frequent mitotype in EmiliaRomagna region (Italy). This assay can be used to identify honey produced by these two subspecies and for population genetic studies in A. mellifera using the honey as source of DNA.
NSTL
Elsevier