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2.
Se Pu ; 40(5): 409-422, 2022 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-35478000

RESUMO

To ensure the success of large-scale sporting events, prevent the contamination of food by prohibited substances, and evaluate the risk of foodborne stimulants and other hormones in food, it is necessary to establish a high-throughput, rapid, and accurate detection method for foodborne stimulants and other hormones. In this study, a QuEChERS method is proposed for the simultaneous determination of 44 foodborne stimulants and 6 progestogens using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The analyzed foodborne stimulants include 19 ß2-agonists, 3 ß-blockers, 11 anabolic agents, 8 glucocorticoids, and 3 diuretics. A meat sample was crushed and homogenized, following which the internal standard was added. Subsequently, the sample was shaken and extracted with water and an acetonitrile solution containing 0.5% acetic acid, then dehydrated and centrifuged with sodium chloride and anhydrous magnesium sulfate. The supernatant was purified by PSA, C18, neutral alumina, and anhydrous magnesium sulfate. It was then dried with nitrogen and concentrated. The concentrated extracts were separated using an ACQUITY BEH C18 column (100 mm×2.1 mm, 1.7 µm) with gradient elution using 0.1% formic acid-5 mmol/L ammonium acetate solution and methanol as mobile phases. The target compounds were detected by ultra-performance liquid chromatography-tandem mass spectrometry with electrospray ionization and positive ion scanning (ESI+) in the multiple reaction monitoring (MRM) mode, and quantified by the internal standard method. The linear ranges of ß2-agonists and ß-blockers were 0.1-20 µg/L, the linear ranges of glucocorticoids were 0.5-200 µg/L, and those of the others were approximately 0.2-50 µg/L. The linear relationships of 50 compounds were good, with correlation coefficients >0.99 in the linear ranges, and limits of quantification (LOQs) in the range of 0.1-0.4 µg/kg. The recoveries of the 50 target compounds spiked in chicken, pork, beef, lamb samples at three levels ranged from 50.3% to 119.9%, while the relative standard deviations (RSDs, n=6) ranged from 0.42% to 15.1%. Nine meat samples (including 3 beef, 3 pork, 2 chicken, and duck samples) were tested by this method and the national standard method (GB/T 21981-2008). The t test was used for statistical analysis of the hydrocortisone and cortisone contents, and no significant difference was found between the results obtained by the two methods. The developed method was used to analyze 12 beef samples from a farm. In all, 4 compounds were detected, while the other 46 were not detected. The content ranges and detection rates of the compounds were as follows: hydrocortisone: 3.3-22.6 µg/kg, 100%; cortisone: 1.5-2.1 µg/kg, 67%; androstenedione: 0.7-1.2 µg/kg, 17%; and testosterone: 0.6-1.5 µg/kg, 42%. In conclusion, the proposed method is simple, accurate, and sensitive, and hence, is suitable for the detection of foodborne stimulants and progestogens in different kinds of raw meat.


Assuntos
Cortisona , Carne Vermelha , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Glucocorticoides , Hidrocortisona , Sulfato de Magnésio , Progestinas , Carne Vermelha/análise , Ovinos , Espectrometria de Massas em Tandem
3.
Front Public Health ; 10: 784668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372239

RESUMO

Affected by the coronavirus disease 2019 (COVID-19), there were short-term uncertainties in China's live pig industry supply chain. Due to the insufficient supply of pork, the price of pork rose from 33.21 yuan/kg at the end of 2019 to 37.46 yuan/kg in mid-February and fell to 26.41 yuan/kg in mid-May. To restore pig supply and stabilise prices, China issued relevant policies. Given the current effective control of COVID-19 in China, this paper constructed an evolutionary game model of China's pork supply and demand stakeholders under normalisation of COVID-19 prevention and control, analysed the behavioural strategies of consumers, government, and pig farmers, used MATLAB software for data simulation, and expounded on the evolution path and the characteristic rule of tripartite decision-making behaviours. The results showed that government supervision costs, evaluation of government by consumers and pig farmers, government subsidies to pig farmers and consumers, and the proportion of stakeholder behaviours affected the formation of tripartite relationships. The results provide a useful reference for the government to formulate effective policies, increase pig supply, and stabilise pork prices.


Assuntos
COVID-19 , Carne de Porco , Carne Vermelha , Animais , COVID-19/prevenção & controle , China , Governo , Humanos , Suínos
5.
Food Chem ; 387: 132872, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35390604

RESUMO

This study aimed to investigate the effects of standing curing (SC), tumbling curing (TC), vacuum tumbling curing (VTC) and ultrasonic-assisted curing (UAC) on the edible quality of black pork and property of myofibrillar proteins (MPs) extracted from black pork. The results showed that all curing methods could improve the marinating absorptivity and the gel water retention of black pork, the solubility and surface hydrophobicity of myofibrillar proteins, and reduce the cooking loss and shear force of black pork, the hydrogen bond content of myofibrillar proteins and the gel whiteness compared with the control group (SC). The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the concentration of protein bands by VTC treatment was decreased obviously. In addition, the result of the scanning electron microscope (SEM) presented that tumbling and ultrasound treatment would destroy the structure of muscle fibers and make them loose and disordered.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Culinária , Eletroforese em Gel de Poliacrilamida , Proteínas , Solubilidade , Suínos
6.
Food Chem ; 387: 132917, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413556

RESUMO

To explore the nutritional values of meat and meat analogues, the in vitro protein digestion of pork, beef, plant-based pork and beef were evaluated. In the gastric phase, the digestibility of pork was significantly higher than that of the plant-based pork, while the value of beef was lower than that of the plant-based beef. In the intestinal phase, both pork and beef showed higher digestibility than plant-based meat analogues. A greater number of small molecular peptides were identified from pork and beef than from plant-based meat after gastrointestinal digestion. Larger quantities of potential bioactive peptides were released from the meat than from the plant-based meat analogues during digestion. These differences were closely related to protein secondary structure, the formation of disulfide bonds and apparent viscosity of digestion solution. The findings give a new insight into the underlying mechanisms of the different phenotype responses of consumers to meat and plant-based meat.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Bovinos , Digestão/fisiologia , Carne/análise , Valor Nutritivo , Peptídeos
7.
Food Chem ; 386: 132830, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35364500

RESUMO

This study investigated the influence of a protease from Staphylococcus (S.) epidermidis on the hydrolysis and flavor development in pork myofibrillar protein (MP). The surface hydrophobicity, fluorescence, Fourier transform infrared spectra, and atomic force microscopy analysis indicated that hydrolysis significantly changed surface hydrophobicity and secondary structure of MP (p < 0.05), and improved the stability of MP in water. The contents of free amino acid from MP, especially glutamic and alanine, significantly increased (p < 0.05), and the production of volatile compound such as aldehydes, alcohols and acid were promoted under the action of protease. MP treated with S. epidermidis protease is non-cytotoxic to the HEK-293 cells. Molecular docking analysis suggested that the interaction between the protease and actin was spontaneous and mainly involved hydrogen bonding forces. In summary, this study provides a theoretical basis for the future application of S. epidermidis protease in fermented meat products.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Endopeptidases , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Peptídeo Hidrolases , Proteínas , Staphylococcus epidermidis , Suínos
8.
Food Chem ; 386: 132856, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35367799

RESUMO

Pangasius hypopthalmus is well known as a good source of protein. However, Pangasius hypopthalmus meat (PHM) can be adulterated with pork for economic concern, thus, analytical methods for authentication are required. Untargeted metabolomics and proteomics using liquid chromatography-high resolution mass spectrometry (LC-HRMS) and chemometrics of principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) was successfully used to differentiate authentic and adulterated PHM with the good of fitness (R > 0.95) and good of predictivity (Q > 0.5). Metabolites of PC(o-18:0/18:2(9Z,12Z)) was found to be a potential marker for pork whereas DMPC (dimyristoylphosphatidylcholine) was a potential marker for PHM. Meanwhile, pork peptide marker of myoglobin (HPGDFGADAQGAMSK) and ß-hemoglobin (FFESFGDLSNADAVMGNPK) could be identified. Both metabolomics and proteomics using LC-HRMS could detect pork at the lowest concentration level (0.5% w/w). In conclusion, untargeted metabolomics and proteomics using LC-HRMS in combination with chemometrics could be used as powerful methods to detect pork adulteration in fish meat.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Biomarcadores , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Carne , Metabolômica/métodos , Proteômica , Suínos
9.
Anal Bioanal Chem ; 414(13): 3885-3894, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35380231

RESUMO

African swine fever virus (ASFV) is the pathogen of African swine fever, a highly contagious and fatal disease of wild boar and domestic pigs. The flow of ASFV through pork products is more concealed, higher risky, and more difficult to prevent and control. Presently, on-site ASFV detection methods in preclinical infected pigs and circulated pork products are lacking. Here, fluorescent test strip-based rapid ASFV detection method in pork was established combined with recombinase aided amplification (RAA) and quantum dot microspheres (QDMs). This method is specific to ASFV with no cross-reactivity to pseudorabies virus (PRV), porcine circovirus type 2 (PCV2), and porcine reproductive and respiratory syndrome virus (PRRSV). The method also showed highly sensitivity with a detection limit of 1 copy for ASFV plasmid templates containing B646L gene and 100 copies/g for DNA extracts from clinical pork samples within a short detection time of less than 25 min. Additionally, the method showed 99.17% consistency with real-time PCR in the ASFV detection of 120 clinical pork samples. Overall, the QDMs-based test strip method provides specific, sensitive, rapid, and simple detection of ASFV in pork, which may contribute to maintain the food safety of pork products, and facilitate ASFV traceability and prevention. Rapid and sensitive detection of African swine fever virus in pork by QDMs based test strip assay.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Carne de Porco , Pontos Quânticos , Carne Vermelha , Febre Suína Africana/diagnóstico , Vírus da Febre Suína Africana/genética , Animais , Hidrolases , Microesferas , Recombinases , Suínos
10.
J Anim Sci ; 100(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35289901

RESUMO

The study aimed to assess the effect of vitamin E (VE) supplementation and fat source on growth performance, lean growth, organ size, carcass characteristics, and pork quality of pigs at a heavy slaughter weight of 150 kg. A total of 64 pigs (32 barrows and 32 gilts; 28.41 ± 0.83 kg) were blocked by sex and body weight, and randomly assigned to one of eight dietary treatments (n = 8 per treatment) in a 4 × 2 factorial arrangement with main effects of fat source (corn starch [CS; no fat added], 5% tallow [TW], 5% distiller's corn oil [DCO], and 5% coconut oil [CN]) and VE supplementation level (11 and 200 ppm). Five-phase diets were formulated to meet requirement estimates of NRC and fed to pigs with each period of 25 kg from 25 to 150 kg. Increasing dietary VE supplementation from 11 to 200 ppm tended to increase average daily gain (ADG) in phase 5 (P = 0.08), and gain to feed ratio (G/F) in phase 4 (P = 0.06) and phase 5 (P = 0.06) resulting in increased G/F in the overall period (P = 0.10). Compared with the pigs fed the CS diet in the overall period, the pigs fed DCO diets had greater ADG (P < 0.05), the pigs fed the TW and CN diets had lower average daily feed intake (P < 0.05), and the pigs fed the fat-added diets had greater G/F (P < 0.05). Belly firmness was greatest in the pigs fed the CN diet and lowest in those fed the DCO diet (P < 0.05). Increasing dietary VE level from 11 to 200 ppm increased absolute and relative liver weight, absolute ham yield (P < 0.05), and tended to increase the relative yield of picnic shoulder (P = 0.07) and ham (P = 0.06) and the pigs fed the corn oil diet tended to have greater belly yield (P = 0.08) than the other fat treatments. Increasing dietary VE level increased 45-min pH and ΔpH at slaughter but decreased a* value, chroma (P < 0.10), and belly depth (P < 0.05). However, no effects of VE supplementation and fat source were observed on the other carcass traits and meat quality measurements. In conclusion, increasing dietary VE level from 11 to 200 ppm slightly increased growth rate and feed efficiency in the late finishing periods, and the addition of fat increased feed efficiency and backfat thickness, decreased lean content, and altered belly firmness. While there were some effects of VE supplementation and fat source observed on organ weight, primal cuts, carcass traits, and meat quality, there was no strong evidence that VE supplementation and fat source materially affected these measurements except for belly firmness.


The study aimed to assess the effect of vitamin E (VE) supplementation and fat source on growth performance, carcass characteristics, and pork quality of pigs slaughtered at 150 kg. Fat sources included corn starch (no fat added), or 5% tallow, distiller's corn oil (DCO), or coconut oil (CN); VE supplementation levels were 11 and 200 ppm. Increasing dietary VE from 11 to 200 ppm tended to increase the efficiency of conversion of feed to body weight gain for the overall study period. The pigs fed the DCO diet had greater backfat depth at slaughter. Belly (from which bacon is made) firmness was greatest in the pigs fed the CN diet and lowest in those fed the DCO diet. In conclusion, increasing dietary VE levels from 11 to 200 ppm slightly increased growth rate and feed efficiency, and the addition of fat increased feed efficiency and backfat thickness, decreased lean muscle content, and altered belly firmness. While there were some effects of VE supplementation and fat source, there was no strong evidence that VE supplementation and fat source materially affected these measurements except for belly firmness.


Assuntos
Carne de Porco , Carne Vermelha , Tecido Adiposo/metabolismo , Ração Animal/análise , Animais , Composição Corporal , Óleo de Milho/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Feminino , Carne , Tamanho do Órgão , Sus scrofa , Suínos , Vitamina E/metabolismo , Vitamina E/farmacologia
11.
PLoS One ; 17(3): e0265445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35298535

RESUMO

Food animals are known reservoirs of multidrug-resistant (MDR) Escherichia coli, but information regarding the factors influencing colonization by these organisms is lacking. Here we report the genomic analysis of 66 MDR E. coli isolates from non-redundant veal calf fecal samples. Genes conferring resistance to aminoglycosides, ß-lactams, sulfonamides, and tetracyclines were the most frequent antimicrobial resistance genes (ARGs) detected and included those that confer resistance to clinically significant antibiotics (blaCMY-2, blaCTX-M, mph(A), erm(B), aac(6')Ib-cr, and qnrS1). Co-occurrence analyses indicated that multiple ARGs significantly co-occurred with each other, and with metal and biocide resistance genes (MRGs and BRGs). Genomic analysis also indicated that the MDR E. coli isolated from veal calves were highly diverse. The most frequently detected genotype was phylogroup A-ST Cplx 10. A high percentage of isolates (50%) were identified as sequence types that are the causative agents of extra-intestinal infections (ExPECs), such as ST69, ST410, ST117, ST88, ST617, ST648, ST10, ST58, and ST167, and an appreciable number of these isolates encoded virulence factors involved in the colonization and infection of the human urinary tract. There was a significant difference in the presence of multiple accessory virulence factors (VFs) between MDR and susceptible strains. VFs associated with enterohemorrhagic infections, such as stx, tir, and eae, were more likely to be harbored by antimicrobial-susceptible strains, while factors associated with extraintestinal infections such as the sit system, aerobactin, and pap fimbriae genes were more likely to be encoded in resistant strains. A comparative analysis of SNPs between strains indicated that several closely related strains were recovered from animals on different farms indicating the potential for resistant strains to circulate among farms. These results indicate that veal calves are a reservoir for a diverse group of MDR E. coli that harbor various resistance genes and virulence factors associated with human infections. Evidence of co-occurrence of ARGs with MRGs, BRGs, and iron-scavenging genes (sit and aerobactin) may lead to management strategies for reducing colonization of resistant bacteria in the calf gut.


Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Carne Vermelha , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bovinos , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Testes de Sensibilidade Microbiana , Fatores de Virulência/genética , beta-Lactamases/genética
12.
Anal Chim Acta ; 1202: 339390, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35341534

RESUMO

Variable selection is a critical step for designing a dedicated multispectral real-time system from multicollinearity spectral data. It improves the prediction ability of the calibration model and provides faster prediction by reducing the curse of dimensionality. The main objective of this study was to compare the effect of variables selection algorithms on model performance for predicting moisture content in red meat using visible and near-infrared (VNIR) hyperspectral imaging in the spectral range of 400-1000 nm and corn using near-infrared (NIR) spectroscopy in the spectral range of 1100-2498 nm. Six variable selection algorithms including the size of the regression coefficient (RC), variable importance in projection (VIP), genetic algorithm (GA), competitive adaptive reweighted sampling (CARS), successive projection algorithm (SPA), and stepwise regression (SWR) were tested and compared to realize their effects on the model performance for predicting moisture content in red meat and corn. The model based on competitive adaptive reweighted sampling-partial least squares regression (CARS-PLSR) was the best model to predict moisture content in red meat and corn. The results indicated the effectiveness of variable selection for providing the feature wavelengths to design a low-cost, real-time multispectral system.


Assuntos
Carne Vermelha , Espectroscopia de Luz Próxima ao Infravermelho , Algoritmos , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Zea mays
13.
J Agric Food Chem ; 70(13): 4112-4122, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35344358

RESUMO

Screening for ″zero tolerance″ ß-agonists requires broad-specificity and sensitivity methods. Herein, R-(-)-salbutamol (SAL) is chirally separated and designed as a hapten, and a monoclonal antibody (mAb) was first prepared with an IC50 of 0.27 ng/mL, which can recognize 38 ß-agonists simultaneously. The broad-specificity of chiral mAb was explored by molecular simulation technology. Magnetic nanoparticles (MNPs) were then synthesized and applied as a signal tracer to develop a lateral flow immunoassay (LFIA). The limits of detection of MNPs-LFIA for SAL in swine urine and pork were 0.05 and 0.09 µg/kg, which was (2-125)-fold lower than that of the reported LFIAs. The recoveries were between 95.8 and 116.7%, with the coefficient of variation from 2.7 to 15.4%. Parallel analysis of 44 samples by commercial ELISA kits confirmed the reliability. Therefore, our work not only provides a broad-specificity and ultrasensitive method for ß-agonists but also suggests that chirality is the new general theory that guided the rational hapten design.


Assuntos
Carne de Porco , Carne Vermelha , Albuterol , Animais , Anticorpos Monoclonais , Imunoensaio/métodos , Fenômenos Magnéticos , Carne Vermelha/análise , Reprodutibilidade dos Testes , Suínos
14.
J Food Prot ; 85(5): 879-889, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35294002

RESUMO

ABSTRACT: The primary objective of this study was to monitor viability of Shiga toxin-producing Escherichia coli (STEC), Salmonella spp., and Listeria monocytogenes during preparation and storage of fuet. Regarding methodology, coarse-ground pork (ca. 35% fat) was mixed with salt (2.5%), dextrose (0.3%), starter culture (ca. 7.0 log CFU/g), celery powder (0.5%), and ground black pepper (0.3%) and then separately inoculated with a multistrain cocktail (ca. 7.0 log CFU/g) of each pathogen. The batter was stuffed into a ca. 42-mm natural swine casing and fermented at 23 ± 2°C and ca. 95% ± 4% relative humidity to ≤pH 5.3 (≤48 h). Sausages were then dried at 12 ± 2°C and ca. 80% ± 4% relative humidity to a water activity (aw) of 0.89 (within 33 days) or aw 0.86 (within 60 days). A portion of each batch of fuet was subjected to high-pressure processing (HPP; 600 MPa for 3 min) before chubs were vacuum packaged and stored for 30 days at 20 ± 2°C. The results revealed that pathogen numbers remained relatively unchanged after fermentation (≤0.35 log CFU/g reduction), whereas reductions of ca. 0.8 to 3.2 log CFU/g were achieved after drying fuet to aw 0.89 or 0.86. Regardless of whether fuet was or was not pressure treated, additional reductions of ca. 2.2 to ≥5.3 log CFU/g after drying were achieved following 30 days of storage at 20°C. For non-HPP-treated fuet dried to aw 0.89 and stored for 30 days at 20°C, total reductions of ≥5.3 log CFU/g in levels of STEC or Salmonella spp. were achieved, whereas levels of L. monocytogenes were reduced by ca. 3.6 log CFU/g. Total reductions of ≥5.3 log CFU/g in levels of all three pathogens were achieved after drying non-HPP-treated fuet to aw 0.86. For fuet dried to aw 0.89 or 0.86, that were pressure treated and then stored for 30 days at 20°C, total reductions of >6.2 log CFU/g in levels of all three pathogens were achieved. In conclusion, the processing parameters tested herein, with or without application of HPP, validated that reductions of ≥2.0 or ≥5.0 log CFU/g in levels of STEC, Salmonella spp., and L. monocytogenes were achieved during preparation and storage of fuet.


Assuntos
Listeria monocytogenes , Carne de Porco , Carne Vermelha , Escherichia coli Shiga Toxigênica , Animais , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Salmonella , Suínos
17.
Food Chem ; 385: 132543, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35287104

RESUMO

Chinese indigenous pigs are favored for their rich flavor, which is generated through complex reactions involving lipid-oxidation-related flavor precursors. In this research, we characterized the aroma compounds and fatty acids of representative Chinese pig breeds by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) and GC-ion mobility spectrometry (GC-IMS) with multivariate analysis. A total of 79 volatile compounds were identified, among which 15 compounds were selected as odorants in pork. According to multivariate statistical analysis, some odorants, including hexanal, 1-octen-3-ol, 2,3-octanedione, (E, E)-2,4-decadienal and dodecanal could be discriminative compounds explaining breed-originated differences in flavor profiles. As confirmed by partial least squares regression (PLS-R), some fatty acids, including C18:1n9c, C22:6n3 and C18:3n3, were major precursors for the formation of rich flavor in indigenous pig breeds. These results revealed that fatty acids and volatile compounds were breed-dependent, and the differences in flavor were related to the variance in the fatty acid content.


Assuntos
Carne de Porco , Carne Vermelha , Compostos Orgânicos Voláteis , Animais , China , Ácidos Graxos , Análise Multivariada , Odorantes/análise , Olfatometria/métodos , Carne Vermelha/análise , Suínos/genética , Compostos Orgânicos Voláteis/análise
18.
Food Chem ; 385: 132651, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35287109

RESUMO

Electronic nose (E-nose) and hyperspectral image (HSI) were combined to evaluate mutton total volatile basic nitrogen (TVB-N), which is a comprehensive index of freshness. The response values of 10 E-nose sensors were collected, and seven responsive sensors were screened via histogram statistics. Reflectance spectra and image features were extracted from HSI images, and the effective variables were selected through random frog and Pearson correlation analyses. With multi-source features, an input-modified convolution neural network (IMCNN) was constructed to predict TVB-N. The seven E-nose sensors, spectra of effective wavelengths (EWs), and five important image features were combined with IMCNN to achieve the best result, with the root mean square error, correlation coefficient, and ratio of performance deviation of the prediction set of 3.039 mg/100 g, 0.920, and 3.59, respectively. Hence, the proposed method furnishes an approach to accurately analyze mutton freshness and provide a technical basis for investigation of other meat qualities.


Assuntos
Nariz Eletrônico , Carne Vermelha , Imageamento Hiperespectral , Carne/análise , Redes Neurais de Computação , Nitrogênio/análise , Carne Vermelha/análise
19.
Food Chem ; 385: 132650, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35306239

RESUMO

Starch (S) films containing gellan gum (90:10) and polyester (P) blend films (PLA:PHBV, 75:25) with and without ferulic, p-coumaric or protocatechuic acid at 2% (w/w) were obtained by melt-blending and compression moulding for the purposes of obtaining SP bilayers by thermo-compressing both monolayers together. These were characterised as to their mechanical and barrier properties and as to their performance as packaging materials for pork meat slices. The incorporation of phenolic acids promoted the water vapour and oxygen barrier capacity of bilayers while reducing their stiffness and resistance to break, mainly in the case of protocatechuic acid. Phenolic acids significantly improved the antioxidant capacity of the bilayer films, reducing the lipid oxidation of packaged meat during storage. Phenolic acid loaded bilayers also reduced the microbial counts of meat, mainly for lactic acid bacteria. These effects positively affected the development of the sample pH and colour parameters throughout storage. Active starch-polyester bilayer films exhibited great potential as a means of extending the shelf-life and improving the quality preservation of pork meat.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Embalagem de Alimentos , Hidroxibenzoatos , Carne/microbiologia , Poliésteres/química , Amido/química , Suínos
20.
Int J Biol Macromol ; 206: 481-488, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35245574

RESUMO

To obtain an analogue of pork backfat (PBF), we combined emulsion and gel to fabricate emulsion gel, which was prepared by using soybean protein isolate (SPI) and curdlan (CL) through a facile heat-treatment method in this paper. The microstructures, rheology properties, water holding capacity and freeze-thawing stability of the emulsion gel were investigated. The results suggested that the SPI/CL-stabilized emulsion gel was thermal-irreversible, and SPI was the emulsifying agent of the emulsion gel. Oil contents significantly affect the water holding capacity and freeze-thawing stability of emulsion gel. Subsequently, the TPA, gel strength and color of emulsion gels with different oil contents were compared with PBF. The hardness, chewiness, springiness, and gel strength of emulsion gel with 10 wt% oil contents were no significant differences from that of PBF (P > 0.05). Hence, this SPI/CL based emulsion gel can be used as an analogue to PBF, providing an alternative ingredient for the development of plant-based low-fat meat products.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Emulsões , Géis/química , Proteínas de Soja/química , Suínos , Água , beta-Glucanas
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