scholarly journals The Preparation and Characterization of Quantum Dots in Polysaccharide Carriers (Starch/Chitosan) as Elements of Smart Packaging and Their Impact on the Growth of Microorganisms in Food

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7732
Author(s):  
Wiktoria Grzebieniarz ◽  
Nikola Nowak ◽  
Gohar Khachatryan ◽  
Marcel Krzan ◽  
Magdalena Krystyjan ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Environmental Changes ◽  
Potato Starch ◽  
Microbiological Quality ◽  
Absorption Capacity ◽  
Poultry Meat ◽  
Food Storage ◽  
Fluorescent Properties ◽  
Smart Packaging ◽  
Vis Spectroscopy

Nanocomposite materials are increasingly commonly used to ensure food safety and quality. Thanks to their unique properties, stemming from the presence of nanoparticles, they are used to develop advanced sensors and biosensors, e.g., for various harmful substances, heavy metals, microorganism growth, and environmental changes in food products. The aim of this study is to produce novel films based on natural resources—potato starch and chitosan—incorporating generated quantum dots of zinc sulfide and cadmium sulfide. The biocomposites were subjected to the following assays: FTIR spectroscopy, UV-VIS spectroscopy, photoluminescence spectroscopy, and SEM/TEM spectroscopy. Their mechanical properties were also analyzed, a colorimetric analysis was performed, and the water content, solubility, and water absorption capacity were determined. A storage test was also performed, using poultry meat covered with the produced films, to assess the microbiological quality. The results confirmed the presence of the quantum dots in the starch–chitosan matrix. The unique optical properties of the films were also demonstrated. It was shown that the composites with nanoparticles limited the growth of selected microorganisms in poultry meat. The food storage time was found to have an impact on the fluorescent properties of the composites. The results point to the possibility of using the produced films as active and smart packaging.

scholarly journals Developing a magnetic nanocomposite adsorbent based on carbon quantum dots prepared from Pomegranate peel for the removal of Pb(II) and Cd(II) ions from aqueous solution

2021 ◽  
Vol 4 (03) ◽  
pp. 33-46
Author(s):  
Hamideh Asadollahzadeh ◽  
Mahdiyeh Ghazizadeh ◽  
Mohammad Manzari
Keyword(s):  
Quantum Dots ◽  
Solid Phase ◽  
Absorption Spectrometry ◽  
Carbon Quantum Dots ◽  
Absorption Capacity ◽  
Good Choice ◽  
Batch Adsorption ◽  
Pomegranate Peel ◽  
Flame Atomic Absorption ◽  
Vis Spectroscopy

Agriculture waste is a good choice for the production of carbon dots owing to its abundance, wide availability, eco-friendly nature. In this study a novel magnetic bioadsorbent based on carbon quantum dots (Fe3O4-PPCQDs) from Pomegranate peel (PP) was used as adsorbent to remove lead (Pb) and cadmium (Cd) from 50 mL of water and wastewater samples by magnetic solid phase extraction (MSPE). After adsorption ions with Fe3O4-PPCQDs at pH=6, the concentration of Pb(II) and Cd (II) ions were determined by flame atomic absorption spectrometry (F-AAS). The manufactured of Fe3O4-PPCQDs and GO nanostructures were structurally characterized by scanning electron microscopy (SEM),  and Fourier transform infrared spectroscopy (FT-IR). The quantum dots were optically characterized by UV–Vis spectroscopy. Batch adsorption experiment was conducted to examine the effects of pH, contact time, temperature and initial concentration of Pb(II) and Cd(II) from the water. The preconcentration factor and LOD for Cd and Pb were obtained 50, and (1.3 μg L-1; 15.5 μg L-1), respectively. The equilibrium data of ions sorption were well described by Langmuir and Freundlich model. The R2 values obtained by Langmuir model were higher. The absorption capacity of Fe3O4-PPCQDs for cadmium and lead were obtained 17.92 and 23.75 mg g-1, respectively. 

scholarly journals Application of Lactiplantibacillus plantarum SCH1 for the Bioconservation of Cooked Sausage Made from Mechanically Separated Poultry Meat

2021 ◽  
Vol 11 (4) ◽  
pp. 1576
Author(s):  
Beata Łaszkiewicz ◽  
Piotr Szymański ◽  
Dorota Zielińska ◽  
Danuta Kołożyn-Krajewska
Keyword(s):  
Sodium Nitrite ◽  
Sensory Quality ◽  
Microbiological Quality ◽  
Poultry Meat ◽  
Control Treatment ◽  
Nitrite Level ◽  
Negative Effect ◽  
Biochemical Identification ◽  
Nitrates Content ◽  
Physical And Chemical

The aim of the research was an assessment of the effect of the Lactiplantibacillus plantarum SCH1 strain isolated from ecological raw fermented pork roast on pH, redox potential, nitrites, and nitrates content, L a* b* color parameters, total heme pigments content, nitrosyl myoglobin concentration, as well as the microbiological quality and sensory traits of cooked sausages produced from mechanically separated poultry meat (MSPM), cured with a lower sodium nitrite level (NaNO2 50 mg/kg) after production as well as after storage (1 and 3 weeks of storage). The biochemical identification of the Lactobacillus bacteria after storage was also performed. Tests were performed in two sausage treatments: C—control sausage made from MSPM and L—sausage made from MSPM inoculated with L. plantarum at approx. 107 cfu/g. No negative effect of using the L. plantarum SCH1 strain on the physical and chemical MSPM sausage features was found. The treatment with L. plantarum SCH1 was of better microbiological quality after 3 weeks of storage. The sausages with L. plantarum SCH1 kept good sensory quality while the control treatment was spoiled after storage.

scholarly journals An Electrochemical Cholesterol Biosensor Based on A CdTe/CdSe/ZnSe Quantum Dots—Poly (Propylene Imine) Dendrimer Nanocomposite Immobilisation Layer

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3368 ◽  
Author(s):  
Kefilwe Mokwebo ◽  
Oluwatobi Oluwafemi ◽  
Omotayo Arotiba
Keyword(s):  
Quantum Dots ◽  
Modified Electrode ◽  
Cholesterol Oxidase ◽  
Shell Growth ◽  
Modified Electrodes ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Poly Propylene ◽  
Cholesterol Biosensor

We report the preparation of poly (propylene imine) dendrimer (PPI) and CdTe/CdSe/ZnSe quantum dots (QDs) as a suitable platform for the development of an enzyme-based electrochemical cholesterol biosensor with enhanced analytical performance. The mercaptopropionic acid (MPA)-capped CdTe/CdSe/ZnSe QDs was synthesized in an aqueous phase and characterized using photoluminescence (PL) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), X-ray power diffraction (XRD), energy dispersive X-ray (EDX) spectroscopy. The absorption and emission maxima of the QDs red shifted as the reaction time and shell growth increased, indicating the formation of CdTe/CdSe/ZnSe QDs. PPI was electrodeposited on a glassy carbon electrode followed by the deposition (by deep coating) attachment of the QDs onto the PPI dendrimer modified electrode using 1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC), and N-hydroxysuccinimide (NHS) as a coupling agent. The biosensor was prepared by incubating the PPI/QDs modified electrode into a solution of cholesterol oxidase (ChOx) for 6 h. The modified electrodes were characterized by voltammetry and impedance spectroscopy. Since efficient electron transfer process between the enzyme cholesterol oxidase (ChOx) and the PPI/QDs-modified electrode was achieved, the cholesterol biosensor (GCE/PPI/QDs/ChOx) was able to detect cholesterol in the range 0.1–10 mM with a detection limit (LOD) of 0.075 mM and sensitivity of 111.16 μA mM−1 cm−2. The biosensor was stable for over a month and had greater selectivity towards the cholesterol molecule.

Fluorine-doped carbon nitride quantum dots: Ethylene glycol-assisted synthesis, fluorescent properties, and their application for bacterial imaging

Carbon ◽  
2016 ◽  
Vol 109 ◽  
pp. 141-148 ◽  
Author(s):  
Nan Wang ◽  
Hai Fan ◽  
Jianchao Sun ◽  
Zhenwei Han ◽  
Jing Dong ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Ethylene Glycol ◽  
Carbon Nitride ◽  
Fluorescent Properties

scholarly journals Microbiological Quality Assessment of Chicken Thigh Fillets Using Spectroscopic Sensors and Multivariate Data Analysis

Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2723
Author(s):  
Evgenia D. Spyrelli ◽  
Christina Papachristou ◽  
George-John E. Nychas ◽  
Efstathios Z. Panagou
Keyword(s):  
Support Vector Machines ◽  
Discriminant Analysis ◽  
Microbiological Quality ◽  
Poultry Meat ◽  
Support Vector ◽  
Classification Models ◽  
Pseudomonas Spp ◽  
Vector Machines ◽  
Ft Ir

Fourier transform infrared spectroscopy (FT-IR) and multispectral imaging (MSI) were evaluated for the prediction of the microbiological quality of poultry meat via regression and classification models. Chicken thigh fillets (n = 402) were subjected to spoilage experiments at eight isothermal and two dynamic temperature profiles. Samples were analyzed microbiologically (total viable counts (TVCs) and Pseudomonas spp.), while simultaneously MSI and FT-IR spectra were acquired. The organoleptic quality of the samples was also evaluated by a sensory panel, establishing a TVC spoilage threshold at 6.99 log CFU/cm2. Partial least squares regression (PLS-R) models were employed in the assessment of TVCs and Pseudomonas spp. counts on chicken’s surface. Furthermore, classification models (linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), support vector machines (SVMs), and quadratic support vector machines (QSVMs)) were developed to discriminate the samples in two quality classes (fresh vs. spoiled). PLS-R models developed on MSI data predicted TVCs and Pseudomonas spp. counts satisfactorily, with root mean squared error (RMSE) values of 0.987 and 1.215 log CFU/cm2, respectively. SVM model coupled to MSI data exhibited the highest performance with an overall accuracy of 94.4%, while in the case of FT-IR, improved classification was obtained with the QDA model (overall accuracy 71.4%). These results confirm the efficacy of MSI and FT-IR as rapid methods to assess the quality in poultry products.

scholarly journals Effects of Olive Leaf Extracts as Natural Preservative on Retailed Poultry Meat Quality

Foods ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1017 ◽  
Author(s):  
Ebeed Saleh ◽  
Alaa Eldin Morshdy ◽  
Eman El-Manakhly ◽  
Sarah Al-Rashed ◽  
Helal F. Hetta ◽  
...  
Keyword(s):  
Microbial Growth ◽  
Microbiological Quality ◽  
Economic Loss ◽  
Sensory Attributes ◽  
Poultry Meat ◽  
Control Group ◽  
Olive Leaf ◽  
Leaf Extracts ◽  
Chilling Period ◽  
Raw Poultry

Poultry meat is commonly marketed at refrigerated temperatures (2–5 °C). The major concern for retailers and consumers is the quality and safety of refrigerated poultry meat. During the chilling period, poultry meat undergoes too many undesirable changes due to microbial growth that leads to spoilage and economic loss. Therefore, this study was conducted to assess the effects of olive leaf extracts (OLE) used at three concentrations (0.25, 0.5, and 1%) on the sensory attributes, as well as the chemical and microbiological quality of raw poultry meat stored at 4 ± 1 °C for 15 days. The results revealed that the OLE addition reduced microbial growth successfully, and maintained the chemical quality and sensory attributes of poultry meat. Moreover, OLE extended the shelf-life of the poultry meat that held under proper refrigeration conditions up to 15 days compared to the control group, that was completely spoiled by the sixth day of storage. This study concludes that OLE could be used both as a natural antioxidant and an antimicrobial preservative for chilled poultry meat held at refrigerated temperature.

Enteric Bacteriophages as Potential Fecal Indicators in Ground Beef and Poultry Meat

2002 ◽  
Vol 65 (1) ◽  
pp. 93-99 ◽  
Author(s):  
F.-C. HSU ◽  
Y.-S. CAROL SHIEH ◽  
M. D. SOBSEY
Keyword(s):  
Microbiological Quality ◽  
Ground Beef ◽  
Chicken Meat ◽  
Detection Sensitivity ◽  
Fecal Coliforms ◽  
Poultry Meat ◽  
Chicken Breast ◽  
Fecal Indicators ◽  
Somatic Coliphages ◽  
Critical Control Points

Recovery efficiencies of enteric bacteriophages (F+ RNA coliphages, somatic coliphages, and Salmonella phages) as alternative fecal indicators were determined from ground beef and chicken breast meat using amino acid eluants (glycine and threonine) and a complex eluant (3% beef extract). Levels of F+ RNA coliphages (MS2, GA, Qβ, FI, and SP), the somatic coliphage ΦX174, and three environmental isolates of Salmonella phages (isolated from raw sewage) were assayed using three respective hosts: Escherichia coli Famp, E. coli C, and Salmonella Typhimurium. When 8% polyethylene glycol and 0.1 M NaCl were used to precipitate bacteriophages eluted with five different eluants, the highest recoveries of the three phage groups were with 0.5 M threonine and 0.25 M glycine-threonine. The average recoveries of F+ RNA coliphages, somatic coliphages, and the Salmonella phages from ground beef and chicken meat were 100, 69, and 65%, respectively, with threonine (0.5 M, pH 9.0) as the eluate. Of eight market food samples tested, F+ RNA coliphages were detected in five (63%) and somatic coliphages were detected in seven (88%). The overall detection sensitivity of the method was 3 PFU/100 g of ground beef or chicken meat. Levels of bacteriophages and bacterial indicators on chicken carcass surfaces were determined at identified critical control points at a poultry plant. Through the processing steps of evisceration, washing, and chilling, the levels of F+ RNA coliphages and fecal coliforms were reduced by 1.6 and 1.9 log10 PFU or CFU/100 g, respectively. F+ RNA coliphages and perhaps other enteric bacteriophages may be effective candidate indicators for monitoring the microbiological quality of meat, poultry, and perhaps other foods during processing. The bacteriophage concentration method developed provides a simple, rapid, and practical tool for the evaluation of fecal contamination levels in ground beef and processed chicken meat.

Fabrication of mono-dispersed silica-coated quantum dot-assembled magnetic nanoparticles

RSC Advances ◽  
2015 ◽  
Vol 5 (41) ◽  
pp. 32072-32077 ◽  
Author(s):  
San Kyeong ◽  
Cheolhwan Jeong ◽  
Han Young Kim ◽  
Do Won Hwang ◽  
Homan Kang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Quantum Dot ◽  
Silica Nanoparticles ◽  
Fluorescent Properties

Quantum dots-embedded silica nanoparticles with an iron oxide NP core were prepared and exhibited super-paramagnetic and highly fluorescent properties.

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