ACS Omega
·
2022
·
IF 4.132
Qiaoling Yang,Bing Niu,Shuqing Gu,Jinge Ma,Chaomin Zhao,Qin Chen,Dehua Guo,Xiaojun Deng,Yongai Yu,Feng Zhang
To develop a rapid detection method for nonprotein nitrogen adulterants, this experiment sets up a set of point-scan Raman hyperspectral imaging systems to qualitatively distinguish and quantitatively and positionally analyze samples spiked with a single nonprotein nitrogen adulterant and samples spiked with a mixture of nine nonprotein nitrogen adulterants at different concentrations (5 × 10–3 to 2.000%, w/w). The results showed that for samples spiked with single nonprotein nitrogen adulterants, the number of pixels corresponding to the adulterant in the region of interest increased linearly with an increase in the analyte concentration, the average coefficient of determination (R2) was above 0.99, the minimum detection concentration of nonprotein nitrogen adulterants reached 0.010%, and the relative standard deviation (RSD) of the predicted concentration was less than 6%. For the sample spiked with a mixture of nine nonprotein nitrogen adulterants, the standard curve could be used to accurately predict the additive concentration when the additive concentration was greater than 1.200%. The detection method established in this study has good accuracy, high sensitivity, and strong stability. It provides a method for technical implementation of real-time and rapid detection of adulterants in milk powder at the port site and has good application and promotion prospects.
研究领域:
食品安全检测
·
光谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
·
2016
·
IF 3.445
Faizan A. Sadiq,Yun Li,TongJie Liu,Steve Flint,Guohua Zhang,Lei Yuan,Zhipeng Pei,GuoQing He
The propensity for aerobic bacilli and allied genera to produce highly heat-resistant spores and thermally stable spoilage enzymes are major bacteriological issues faced by the dairy industry. Most of the enzymes are able to survive any heat treatment applied during the manufacture of milk powders and have the potential to remain active in milk powders and other dairy products during storage, and may explain some of the sensory and functionality defects reported in dairy products . Despite many reports on the occurrence of spore-forming bacteria in dairy products, knowledge about food quality related properties of many aerobic sporeformers is still scarce. Therefore, the aim of this study was to determine thermal resistance and spoilage potential of a large pool of mesophilic and thermophilic sporeformers, representing 738 isolates and 31 different RAPD groups, recently isolated from Chinese milk powders. Spore formers producing highly heat resistant spores (surviving 125 °C for 30 min) included 2 thermophiles ( Geobacillus thermoleovorans group and Geobacillus stearothermophilus ) and one mesophilic species ( Brevibacillus brevis ). Paenibacillus macerans showed the highest proteolytic activity followed by members of the Bacillus cereus group, Br. brevis , Bacillus subtilis , G. thermoleovorans group and Virgibacillus proomii . The highest lipase producing strains belonged to Bacillus licheniformis . Phospholipase activity was only shown by members of the B. cereus group and Brevibacillus parabrevis . Ten strains showed positive β -galactosidase activity, while, 4 strains showed positive haemolytic activity. B. licheniformis strains, despite belonging to one RAPD group or sub-group showed markedly different phenotypic characters which support the previous findings of heterogeneity in RAPD-based B. licheniformis groups. The results of this study will broaden the knowledge about the spoilage potential and thermal resistance of many strains of dairy origin.
研究领域:
食品科学
·
微生物学
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DOI
PubMed
高影响因子
JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY
·
2018
·Vol. 29
·期 1
·2-10
·
IF 1.444
Wang Jian,Tian Lili,Yan Yanan,Liu Yaru,Zhang Yan,Yang Chun
An estradiol templated core-shell magnetic molecularly imprinted cryogel (MMIC) was synthesized to selectively extract and analyze estradiol in milk powder. The microsphere of Fe3O4@SiO2 was firstly prepared on Fe3O4 with ethyl silicate and 3-methyl propyl trimethoxy silane. Then the polymerization of α-methacrylic acid and ethylene glycol dimethyl acrylate was carried out on Fe3O4@SiO2 at −20 ºC for 24 h with estradiol as template. The morphology and microstructure of MMIC were investigated by transmission electron microscopy and infrared spectrogram. When used as chromatographic stationary phase, MMIC showed good selectivity and chromatographic performance for the template. Spiked milk powder samples were used to examine the adsorption capacity and selectivity of MMIC, giving recoveries of 92-101% and limit of detection 0.8-1.2 ng g−1. Experimental results indicate good reproducibility with relative standard deviation from 2.2 to 4.5% (n = 3) at spiked levels of estradiol 10, 50, and 100 ng g-1.
研究领域:
分析化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Food Analytical Methods
·
2024
·
IF 2.6
Zhang Hongtao,Gao Jiahui,Tan Lian,Zheng Li,Wang Longjie
Milk powder is a common food in most families. It is of great significance to accurately detect the quality and safety of milk powder to mitigate food safety problems. This paper presents a method for the determination of vanillin and ethyl vanillin in milk powder based on terahertz (THz) spectroscopy. Samples with varying concentration gradients of these two additives were prepared, and a terahertz time-domain spectrometer was used to collect spectral data from the samples in the 0.2 to 1.5 THz range. Seven spectral preprocessing algorithms were evaluated using the partial least squares (PLS) method, and it was found that the combination of multivariate scattering correction (MSC) and Savitzky-Golay (SG) smoothing preprocessing yielded the best results, significantly improving the accuracy of the test sets for both additives. Subsequently, nine quantitative detection methods were constructed by combining three dimensionality reduction algorithms (ant colony algorithm (ACO), competitive adaptive reweighted sampling (CARS), and successive projection algorithm (SPA)) with three regression models (support vector regression (SVR), long short-term memory (LSTM), and particle swarm optimization-back propagation (PSO-BP)). The results showed that the LSTM regression model, with dimensionality reduction performed by the CARS algorithm, performed best for detecting vanillin in milk powder, achieving a recognition rate of 94.49%. Compared to the other eight methods, this increased the recognition rate by 7.69%. Similarly, the LSTM regression model, combined with the SPA algorithm for dimensionality reduction, performed best for detecting ethyl vanillin in milk powder, reaching a recognition rate of 98.37%. This represented a 6.59% increase in recognition rate over the other eight methods, providing a novel technical approach for non-destructive testing and analysis of milk powder quality and safety.
研究领域:
食品安全
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光谱学
·
生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2014
·
IF 4.258
Hangzhen Lan,Ning Gan,Daodong Pan,Futao Hu,Tianhua Li,Nengbing Long,Li Qiao
A new automated solid-phase micro extraction (SPME) sampling method was developed for quantitative enrichment of estrogens (ES) from milk powder, using magnetic molecularly imprinted polymer (MMIP) as fiber coating. The method (MMIP-SPME) was built with several electromagnetic stainless steel fibers, placed in parallel for simultaneously extraction. The MMIP was synthesized using core–shell Fe 3 O 4 @SiO 2 nanoparticles (NPs) as magnetic support. Estradiol (E2) was employed as the template molecule, acrylamide (AA) as functional monomer, and ethylene glycol dimethacrylate (EGDMA) as cross-linker. MMIP can be easily absorbed or desorbed from fibers when the current is turned on or off, creating magnetism. Compared to traditional MIP-SPME, the prepared procedure of MMIP-SPME is time-saving and organic solvent-free. The proposed device significantly improved the efficiency of separation and enrichment of estrogens from complex matrices thereby and facilitating the pretreatment steps by electromagnetically controlled extraction fibers to achieve full automation. Several experimental parameters were studied, including extraction and desorption kinetics, solution pH, desorption solution, ratio, and shuttle rate. The newly developed MMIP-SPME showed good sensitivity and high binding capacity, fast adsorption kinetics and desorption kinetics for estrone (E1), estradiol (E2), estriol (E3) and diethylstilbestrol (DES) under optimized conditions. The detection limits for the four estrogens were 1.5–5.5 ng g −1 with excellent reproducibility (RSD values less than 7.1%) when milk powder samples spiked with analytes at 20, 100 and 250 ng g −1 were studied.
研究领域:
分析化学
·
环境科学
·
食品科学
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产品关联
DOI
PubMed
高影响因子
Food Analytical Methods
·
2020
·Vol. 14
·期 1
·165-171
·
IF 2.667
Li Xiaozhou,Wang Xinnuo,Wang Lianyan,Yang Tianyue,Wang Deli
Nowadays, the overuse of antibiotics in cow breeding is a common issue worldwide. Real-time monitoring is critical for antibiotic control of dairy products. Herein, we report a rapid detection method for the duplex detection of two beta-lactam antibiotics (cephalexin and ampicillin) in milk powder using lateral flow (LF) combined with surface-enhanced Raman spectroscopy (SERS). The duplex detection was accomplished using a single test line loaded with two antigens targeting the two corresponding antibody-gold-Raman reporter conjugates. The obtained SERS spectra contributed by the Raman reporter labeled to the two antibodies were analyzed using both peak height method and multiple linear regression (MLR). A good regression fitting was achieved by these two methods ( R 2 = 0.99 and 0.98, respectively). The limit of detection (LOD) was 10 −4 ng/mL for both peak height method and MRL. This study indicated that LF-SERS is a good candidate for real-time multiplex and quantitative analysis for antibiotics in dairy products.
研究领域:
食品科学
·
分析化学
✓ 已验证
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2020
·Vol. 413
·期 1
·215-223
·
IF 3.637
Li Na,Zhao Tengwen,Du Li,Zhang Ziyang,Nian Qixun,Wang Manman
A graphitic carbon nitride (g-C 3 N 4 /Fe 3 O 4 )–based magnetic solid-phase extraction (MSPE) approach was established for fast and simple analysis of estrogens in milk powders. The composites were characterized by X-ray diffractometer, scanning electron microscope, and Brunauer-Emmett-Teller surface area and pore size distribution analyzer. Compared with the bulk g-C 3 N 4 , g-C 3 N 4 /Fe 3 O 4 gave a narrower distribution of mesopores and provided an enhanced surface area from 77.1 to 113.7 m 2 /g. Polar analytes of estrogens were selected as model compounds and the extraction of four estrogens was achieved in n-hexane using 15 mg of adsorbent within only 2 min. Possible extraction mechanism of g-C 3 N 4 /Fe 3 O 4 for these estrogens was explored in terms of the polarity of the analytes and the adsorption performance of the adsorbent. The hydrophobicity and the hydrogen-bond interaction between the estrogens and g-C 3 N 4 were responsible for the efficient adsorption. Combined with HPLC, MSPE with the prepared adsorbent gave the enhancement factors of 20 to 24 and the linear ranges of 2–200 μg/kg for 17 β -estradiol and 17 α -ethinylestradiol, 1.5–150 μg/kg for estrone, and 3–300 μg/kg for hexestrol. The detection limits and quantification limits for the estrogens in milk powders were 0.5–0.9 μg/kg and 1.5–3.0 μg/kg, respectively. The recoveries varied from 75.1 to 97.2%, with the intra-day and inter-day precisions ≤ 14.2%. Furthermore, the enrichment of the analytes and the clean-up of fat and protein interferences were achieved simultaneously with one-step g-C 3 N 4 -based MSPE. The present method was convenient, fast, and sensitive, and therefore could be successfully applied for the determination of estrogens in milk powders.
Graphical abstract
研究领域:
分析化学
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Yichang He,Yiquan Liao,Bin Zhang,Ruiqi Xu,Ye Ma,Minggang Zhao,Hongzhi Cui
Melamine added to milk powder can lead to kidney injury and even death, but rapid detection is still hard due to the strong interference of milk powder solution. Herein, the CC/CeO 2 /CNPs mesh was constructed to detect melamine by using the photo-enhanced barrier effects on electrochemical response. Schottky barrier was regulated effectively to produce electrochemical response to melamine by photo-induced electrostatic interaction, which exhibited strong resistance to interference in milk powder solution. Sensitivity was enhanced by nearly 5 times and the lowest detection limit was reduced as low as 0.274 nM. The obtained high recovery (100%-104%) and good stability in milk powder solution indicated the good potential for practical applications. It provides a new opportunity for achieving strong resistance to interference by using the photo-enhanced barrier driving effect on electrochemical response.
研究领域:
分析化学
·
食品安全
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Analytical Methods
·
2016
·Vol. 10
·期 5
·1386-1396
·
IF 2.167
Wang Yu,Gao Lei,Qin Dongli,Chen Ligang
In this work, a simple and selective method based on matrix solid phase dispersion (MSPD) using molecularly imprinted polymers (MIPs) as sorbents was successfully developed for the determination of melamine (MEL) in milk powder. The MIPs have been prepared by surface imprinted polymerization method using carbon nanotube (CNT) as support, MEL as template molecule, γ-aminopropyltriethoxysilane as functional monomer, and tetraethyl orthosilicate as cross-linking agent. The MIPs were characterized by Fourier transform infrared spectrometer and scanning electron microscopy. At the same time, the adsorption isotherm, dynamic adsorption, and selective adsorption of MIPs to MEL were also studied. The prepared MIPs were used as dispersant of MSPD to extraction and separate MEL in milk powder. We optimized the extraction conditions as follows: the ratio of MIPs to sample was 2:3; the dispersion time was 10 min; washing solvent was 2.0 mL acetonitrile; and elution solvent was 4.0 mL ammonium methanol (5:95, v / v ). Once the MSPD process was completed, the MEL extracted from milk powder was determined by LC-MS/MS. Under the optimal conditions, the limit of detection of MEL was 0.2 ng g −1 . The relative standard deviations of intra-day and inter-day were obtained in the range of 0.4∼5.1 %. The satisfied recoveries of MEL were 92.5∼97.2 %. The MIP-MSPD method has some advantages, such as higher selectivity, lower cost of preparation, less time consuming and organic solvent consumption, simpler sample pretreatment procedure, and higher extraction recovery compared with those existing methods which were used for determination of MEL.
研究领域:
食品科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Jin-Kui Ma,Shou-Lian Wei,Qing Tang,Xiao-Chen Huang
Phthalate acid esters (PAEs) with superior performance are widely used. However, the long-term intake of PAEs seriously damages the human body. In this work, a novel type of magnetic molecularly imprinted polymer (mMIP) was synthesized and coupled with gas chromatography–mass spectrometry (GC/MS) for the selective separation and determination of 15 PAEs in milk powder samples. Key mMIP variables, i.e. (1) NaCl dosage, (2) eluent type and amount, (3) extraction and elution time), and (4) reusability, were investigated to determine the optimal magnetic solid phase extraction conditions. Results revealed that the mMIPs had good recognition specificity for the template molecules. Under the optimized conditions, 15 PAEs were successfully separated and analyzed by GC/MS. Results showed a good linearity in the range of 0.05–10.0 μg/mL for different PAEs’ concentration. The detection limit was 0.2–0.8 μg/kg, the average recovery was 83.0%–104%, and the relative standard deviation was 2.4 %–8.6% ( n = 5). This new sample and rapid pretreatment method was successfully applied to the monitoring of trace plasticizing agent residues in milk powder.
研究领域:
分析化学
·
食品安全
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2015
·
IF 3.545
Junrong Li,Guannan Zhang,Lihua Wang,Aiguo Shen,Jiming Hu
In this work, we suggest a chitosan-modified popcorn-like Au–Ag nanoparticles (CSPNPs) based assay for high sensitive detection of melamine , in which CSPNPs not only provide with an intrinsic peroxidase-like activity but also act as surface enhanced Raman scattering (SERS) substrates. CSPNPs can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by H 2 O 2 to the charge transfer complex (CTC), which contributes to a tremendous surface-enhanced resonant Raman scattering (SERRS) signals with 632.8 nm laser excitation. The target molecule melamine can generate an additional compound with H 2 O 2 , which means the available amount of H 2 O 2 for the oxidation of TMB reduced. Correspondingly, the SERRS intensity of CTC is decreased. The decreased Raman intensity is proportional to the concentration of melamine over a wide range from 10 nM to 50 μM ( R 2 =0.989), with a limit of detection (LOD) of 8.51 nM. Moreover, the proposed highly selective method is fully capable of rapid, separation-free detection of melamine in milk powder.
研究领域:
分析化学
·
食品科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Xiaoyu Zhao,Ligang Chen,Bin Li
A novel analytical method for melamine in milk powder has been developed and exploited with three-dimensional (3D) magnetic molecularly imprinted polymers (MMIPs) combining with liquid chromatography-tandem mass spectrometry. The 3D MMIPs were synthesized with graphene-carbon nanotube hybrid composite as carrier which can increase the accessible surface area. The products were characterized, and the binding affinity was investigated by isothermal absorption, kinetic adsorption and selective adsorption. The results showed that the 3D MMIPs exhibited high adsorption capacity with maximum adsorption capacity of 123.1 mg g −1 , fast adsorption rate (10 min) and high selectivity toward melamine. Various affecting extraction parameters were evaluated. The limit of detection was 0.00045 mg kg −1 and the recoveries were ranged from 90.3% to 95.7%. The precisions (RSDs) were lower than 4.7%. This method was applied for analyzing six milk powder samples. The result was in agreement with that obtained by the state standard method used in China.
研究领域:
分析化学
·
食品安全检测
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）