RESUMO
A fluorescence probe based on molecularly imprinted polymers on red emissive biomass-derived carbon dots (r-BCDs@MIPs) was developed to detect tyramine in fermented meat products. The red emissive biomass-derived carbon dots (r-BCDs) were synthesized by the one-step solvothermal method using discarded passion fruit shells as raw materials. The fluorescence emission peak of r-BCDs was at 670 nm, and the relative quantum yield (QY) was about 2.44%. Molecularly imprinted sensing materials were prepared with r-BCDs as fluorescent centers for the detection of trace tyramine, which showed a good linear response in the concentration range of tyramine from 1 to 40 µg L-1. The linear correlation coefficient was 0.9837, and the limit of detection was 0.77 µg L-1. The method was successfully applied to the determination of tyramine in fermented meat products, and the recovery was 87.17-106.02%. The reliability of the results was verified through high-performance liquid chromatography (HPLC). Furthermore, we combined the r-BCDs@MIPs with smartphone-assisted signal readout to achieve real-time detection of tyramine in real samples. Considering its simplicity and convenience, the method could be used as a rapid and low-cost promising platform with broad application prospects for on-site detection of trace tyramine with smartphone-assisted signal readout.
Assuntos
Carbono , Corantes Fluorescentes , Limite de Detecção , Produtos da Carne , Polímeros Molecularmente Impressos , Pontos Quânticos , Smartphone , Tiramina , Tiramina/análise , Tiramina/química , Carbono/química , Pontos Quânticos/química , Produtos da Carne/análise , Corantes Fluorescentes/química , Polímeros Molecularmente Impressos/química , Espectrometria de Fluorescência/métodos , Biomassa , FermentaçãoRESUMO
Diphenylalanine(FF)-Zn self-assembly (FS) confined in covalent organic polymers (FS@COPs) with efficient fluorescence was synthesized for fluorescence sensing of biogenic amines, which was one of the most important indicators for monitoring food freshness. FS@COPs combined excellent biodegradability of self-assembled dipeptide with chemical stability, porosity and targeted site recognition of COPs. With an optimal excitation wavelength of 360 nm and an optimal emission wavelength of 450 nm, FS@COPs could be used as fluorescence probes to rapidly visualize and highly sensitive determination of tryptamine (Try) within 15 min, and the linear range was from 40 to 900 µg L-1 with a detection limit of 63.08 µg kg-1. Importantly, the FS@COPs showed a high fluorescence quantum yield of 11.28%, and good stability, solubility, and selectivity, which could successfully achieve the rapid, accurate and highly sensitive identification of Try. Furthermore, we revealed the mechanism of FS@COPs for fluorescence sensing of targets. The FS@COPs system was applied to the fluorescence sensing of Try in real samples and showed satisfactory accuracy of 93.02%-105.25%.
Assuntos
Dipeptídeos , Corantes Fluorescentes , Limite de Detecção , Espectrometria de Fluorescência , Triptaminas , Triptaminas/análise , Triptaminas/química , Dipeptídeos/química , Dipeptídeos/análise , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Produtos da Carne/análise , Polímeros/químicaRESUMO
Combining intelligent and active packaging serves the dual purpose of detecting color changes in food that reflect changes in its quality and prolonging its shelf life. This study developed an intelligent and active packaging system made from the cellulose of Acetobacter xylinum and assessed its ability to detect changes in the quality and to increase shelf-life of packaged fresh beef. The properties of the intelligent packaging's sensor and active packaging films were determined. The application of this system to fresh beef stored at room temperature (28 ± 2 °C) for 24 h was tested. The color of the bromothymol blue (BTB) solution (pH 2.75) in the indicator of the intelligent packaging system changed from orange to dark green to indicate that beef quality changed from fresh to rotten. The meat treated with the active packaging with 10% and 15% garlic extract decayed on the 16th h. In contrast, the meat treated with the active packaging without the garlic extracts rotted on the 12th h. The shift in the indicator's color was linearly related to the total plate count (TPC), total volatile basic nitrogen (TVBN), and pH of the meat packaged using the active packaging system. Therefore, BTB solution (pH 2.75) can be used as an intelligent packaging indicator that will allow consumers to assess the quality of packaged meat easily. As an antimicrobial agent, the addition of 10-15% garlic extract to the active packaging films can help delay the spoilage of packaged beef.
Assuntos
Gluconacetobacter xylinus , Produtos da Carne , Animais , Bovinos , Celulose , Cor , Embalagem de Alimentos , Concentração de Íons de Hidrogênio , Carne/análiseRESUMO
Food texture is one of the important quality indicators in foodstuffs, along with appearance and flavor, contributing to taste and odor. This study proposes a novel magnetic food texture sensor that corresponds to the tactile sensory capacity of the human tooth. The sensor primarily consists of a probe, linear slider, spring, and circuit board. The probe has a cylindrical shape and includes a permanent magnet. Both sides of the spring are fixed to the probe and circuit board. The linear slider enables the smooth, single-axis motion of the probe during food compression. Two magnetoresistive elements and one inductor on the circuit board measured the probe's motion. A measurement system then translates the measurement data collected by the magnetoresistive elements into compression force by means of a calibration equation. Fundamental experiments were performed to evaluate the range, resolution, repetitive durability of force, and differences in the frequency responses. Furthermore, the sensor was used to measure seven types of chicken nuggets with different coatings. The difference between the force and vibration measurement data is revealed on the basis of the discrimination rate of the nuggets.
Assuntos
Galinhas , Produtos da Carne , Animais , Manipulação de Alimentos , Humanos , Fenômenos Magnéticos , Produtos da Carne/análise , PaladarRESUMO
High molecular weight chitosan (≈322 kDa) was obtained from chitin isolated from Brachystola magna (Girard) to produced biodegradable films. Their physicochemical, mechanical and water vapor permeability (WVP) properties were compared against commercial chitosan films with different molecular weights. Brachystola magna chitosan films (CFBM) exhibited similar physicochemical and mechanical characteristics to those of commercial chitosans. The CFBM films presented lower WVP values (10.01 × 10-11 g/m s Pa) than commercial chitosans films (from 16.06 × 10-11 to 64.30 × 10-11 g/m s Pa). Frankfurt-type sausages were covered with chitosan films and stored in refrigerated conditions (4 °C). Their quality attributes (color, weight loss, pH, moisture, texture and lipid oxidation) were evaluated at 0, 5, 10, 15 and 20 days. Sausages covered with CFMB films presented the lowest weight loss (from 1.24% to 2.38%). A higher increase in hardness (from 22.32 N to 30.63 N) was observed in sausages covered with CFMB films. Compared with other films and the control (uncovered sausages), CFMB films delay pH reduction. Moreover, this film presents the lower lipid oxidation level (0.10 malonaldehyde mg/sample kg). Thus, chitosan of B. magna could be a good alternative as packaging material for meat products with high-fat content.
Assuntos
Quitosana/química , Embalagem de Alimentos , Conservação de Alimentos , Gafanhotos/química , Produtos da Carne , Membranas Artificiais , AnimaisRESUMO
The development of plant-based functional food ingredients has become a major focus of the modern food industry as a response to changes in consumer attitudes. In particular, many consumers are switching to a plant-based diet because of their concerns about animal-derived foods on the environment, human health, and animal welfare. There has therefore been great interest in identifying, isolating, and characterizing functional ingredients from botanical sources, especially waste streams from food and agricultural production. However, many of these functional ingredients cannot simply be incorporated into foods because of their poor solubility, stability, or activity characteristics. In this article, we begin by reviewing conventional and emerging methods of extracting plant-based bioactive agents from natural resources including ultrasound-, microwave-, pulsed electric field- and supercritical fluid-based methods. We then provide a brief overview of different methods to characterize these plant-derived ingredients, including conventional, chromatographic, spectroscopic, and mass spectrometry methods. Finally, we discuss the design of plant-based delivery systems to encapsulate, protect, and deliver these functional ingredients, including micelles, liposomes, emulsions, solid lipid nanoparticles, and microgels. The potential benefits of these plant-based delivery systems are highlighted by discussing their use for incorporating functional ingredients into traditional meat products. However, the same technologies could also be employed to introduce functional ingredients into plant-based meat analogs.
Assuntos
Suplementos Nutricionais , Indústria Alimentícia , Alimento Funcional , Produtos da Carne , Nanopartículas/química , Compostos Fitoquímicos/química , Animais , Humanos , LipossomosRESUMO
BACKGROUND: Bovine hide underlayer is used to manufacture collagen casings for sausage production. Edible collagen casings and natural ovine casing (as a reference) were chosen for analysis. The collagen casings (intended for: A - breakfast sausages, B - scalded sausages and C - dried sausages) were manufactured with the use of glyoxal as a cross-linking agent. The casings properties along with the quality of the sausages manufactured in those casings was analyzed. RESULTS: Casing A had a higher swelling capacity and water solubility, a* and b* color parameters, and wet elongation at break values, as well as a lower shrinking temperature. The remaining mechanical and water parameters were comparable to other collagen casings. The ovine casing contained more water, and was redder and less yellow compared to the collagen casings, whereas swelling, solubility and water vapor permeability were higher. The sausages in casing A were the softest and had the highest a* and b* color parameters. The results of the sensory analysis indicate that the sausages in casing B exhibited the highest quality on a three-point scale among the tested sausages and were also the most acceptable for judges. The ovine casing was graded as the hardest during cutting and also when in the mouth. CONCLUSION: By contrast to the producer's descriptions, the collagen casings were similar with respect to many properties. The differences between sausages in collagen casings were not so distinct as might be expected. Despite our expectations, the sausages in the natural casing were not rated as the best compared to sausages in collagen casings in the sensory analysis. © 2021 Society of Chemical Industry.
Assuntos
Colágeno/química , Manipulação de Alimentos , Produtos da Carne/análise , Pele/química , Animais , Fenômenos Biomecânicos , Bovinos , Manipulação de Alimentos/instrumentação , Humanos , Permeabilidade , Ovinos , Solubilidade , Suínos , PaladarRESUMO
BACKGROUND: The meat industry is determined to find biodegradable packaging with properties similar to plastic. Furcellaran (FUR) and whey protein isolate (WPI) were used as a film matrix in which Borago officinalis extract (BOE) was incorporated as an antioxidant compound. The film's mechanical properties, water behavior, surface color, and antioxidant power were analyzed.Smoked hams were manufactured using two different types of film application: cured meat covered with film, smoked and cooked or hamsafter smoking, cooking and cooling. Smoked, vacuum packed ham was used as a control sample. The products were stored at 4 °C for 21 days and analyzed every 7 days. RESULTS: The elongation at break (EAB) and tensile strength (TS) of FUR/WPI films without the extract were 6.30% and 20.59 MPa, respectively, and after incorporating BOE, the EAB and TS were 24.30% and 15.33 MPa, respectively. The films with BOE were darker and had greater antioxidant capacity. The water content and activity in the products with films decreased along with storage time while the control remained stable. The results of microbiological, oxidation product accumulation, and sensory analysis were comparable in all the products. CONCLUSIONS: The smoking time can be reduced due to the dark color of the hams covered with BOE film. The barrier properties of those films should be increased. Other parameters were comparable to plastic packaging. The films therefore have the potential to be used instead of plastic packaging in the meat industry. © 2020 Society of Chemical Industry.
Assuntos
Alginatos/química , Biopolímeros/química , Borago/química , Embalagem de Alimentos/instrumentação , Produtos da Carne/análise , Extratos Vegetais/química , Gomas Vegetais/química , Proteínas do Soro do Leite/química , Animais , Antioxidantes/química , Fenômenos Biomecânicos , Cor , Oxirredução , Carne de Porco/análise , Suínos , Resistência à TraçãoRESUMO
OBJECTIVE: This study investigated the consumption behaviours of healthcare professionals in relation to red meat and processed red meat products. DESIGN: This study included a questionnaire conducted through face-to-face interviews with 149 health professionals. The purpose of the questionnaire was to determine the extent to which health professionals agreed with the WHO classification of red meat and processed red meat on their list of carcinogenic products. SETTING: This research was carried out in Izmir, which is Turkey's third largest city. The survey was conducted in 2016 by holding face to face interviews with forty-three specialist doctors, sixteen doctors, twelve dentists, sixty-four nurses and fourteen pharmacists. SUBJECTS: Nationally representative sample of healthcare professionals in Turkey. RESULTS: People educated in healthcare are especially cautious about the consumption of processed red meat products. The results of the research revealed the importance of processing and cooking patterns in red meat consumption preferences. CONCLUSIONS: The consequences of the research, in terms of breaking down prejudices and overcoming the anxieties of those with health concerns who do not consume red meat, are important. In fact, the results show that healthcare professionals consume red meat, but they are more careful in their consumption of processed red meat products. This result is in line with the WHO report.
Assuntos
Comportamento Alimentar , Pessoal de Saúde/psicologia , Produtos da Carne/estatística & dados numéricos , Carne Vermelha/estatística & dados numéricos , Adolescente , Adulto , Animais , Atitude do Pessoal de Saúde , Carcinógenos , Bovinos , Comportamento do Consumidor , Culinária , Feminino , Preferências Alimentares , Alimentos em Conserva , Humanos , Masculino , Produtos da Carne/efeitos adversos , Carne Vermelha/efeitos adversos , Ovinos , Inquéritos e Questionários , Turquia , Organização Mundial da Saúde , Adulto JovemRESUMO
Shiga toxin-producing Escherichia coli (STEC) are a leading cause of foodborne illnesses worldwide, with beef and beef products as a common food reservoir. STEC strains may be present in beef-processing environments in the form of biofilms. The exudate of raw beef, also referred to as beef juice, has been identified as an important source of bacterial contamination on food-processing surfaces. This study applied beef juice as a food-based model to study its effects on biofilm formation of six STEC isolates on stainless steel. Crystal violet staining and cell enumeration demonstrated that beef juice inhibited the biofilm formation of strains O113, O145, and O91 up to 24 h at 22°C, but that biofilm increased (p < 0.05) thereafter over 72 h. Biofilms formed by O157, O111, and O45 were not affected by the addition of beef juice over the whole incubation period. Electron microscopy showed that the morphology of biofilm cells was altered and more extracellular matrix was produced with beef juice than with M9 medium. The present study demonstrated that beef juice residues on stainless steel can enhance biofilm formation of some STEC strains. Thorough and frequent cleaning of meat residues and exudate during meat production and handling is critical to reduce STEC biofilm formation even at 13°C.
Assuntos
Biofilmes/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Produtos da Carne/microbiologia , Escherichia coli Shiga Toxigênica/fisiologia , Aço Inoxidável/análise , Animais , Bovinos , Manipulação de Alimentos , Microbiologia de AlimentosRESUMO
The possibility of obtaining a carmine or pink color on ordinary cooked ham by applying natural dyes from three plant species, namely red radish (Raphanus sativus L.), hibiscus (Roselle sabdariffa L.) and red beetroot (Beta vulgaris L.), was investigated. The extracts were evaluated for the stability at physical-chemical parameters and subjected to cytotoxicity assays in the gastric cell line AGS Encapsulation of the extracts in soybean lecithin liposomes and maltodextrin microcapsules was performed. Lyophilized extracts before and after encapsulation in maltodextrin were applied in the formulation of ordinary cooked ham and used in a pilot scale of production. The color of cooked ham samples from different assays was evaluated visually and by colorimetry. The results suggest that the coloration of ordinary cooked ham obtained with extracts of red beetroot is very promising for future applications in this type of meat product.
Assuntos
Beta vulgaris/química , Betalaínas/análise , Culinária/métodos , Produtos da Carne/normas , Extratos Vegetais/análise , Carne de Porco/normas , Betacianinas/análise , Betacianinas/química , Betacianinas/toxicidade , Betalaínas/química , Betalaínas/isolamento & purificação , Betalaínas/toxicidade , Cápsulas/química , Linhagem Celular , Cor , Colorimetria , Corantes/química , Corantes/isolamento & purificação , Hibiscus/química , Humanos , Lecitinas/química , Lipossomos/química , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Polissacarídeos/química , Raphanus/química , Glycine max/químicaRESUMO
BACKGROUND: Low-sodium sausages were manufactured using sodium substitution and biopolymer encapsulation. A diet comprising 10% treatment sausages (six treatment groups: C (100% NaCl), T1 (55% sodium substitute + 45% saltwort salt), T2 (55% sodium substitute + 45% saltwort salt with chitosan), T3 (55% sodium substitute + 45% saltwort salt with cellulose), T4 (55% sodium substitute + 45% saltwort salt with dextrin), and T5 (55% sodium substitute + 45% saltwort salt with pectin)) was added to a 90% commercial mouse diet for 4 weeks. RESULTS: Subacute toxicity, hematology, liver function, and organ weight tests in low-sodium sausage groups showed results similar to those of the control group, and all toxicity test levels were within normal ranges. CONCLUSIONS: All low-sodium sausage types tested are suggested to be safe in terms of subacute toxicity. Moreover, low-sodium sausages can be manufactured by biopolymer encapsulation of saltwort using pectin, chitosan, cellulose, and dextrin without toxicity. © 2019 Society of Chemical Industry.
Assuntos
Biopolímeros/análise , Aditivos Alimentares/análise , Manipulação de Alimentos/métodos , Produtos da Carne/análise , Salsola/química , Sódio/análise , Animais , Biopolímeros/metabolismo , Biopolímeros/toxicidade , Celulose/análise , Celulose/metabolismo , Celulose/toxicidade , Quitosana/análise , Quitosana/metabolismo , Quitosana/toxicidade , Feminino , Aditivos Alimentares/metabolismo , Aditivos Alimentares/toxicidade , Manipulação de Alimentos/instrumentação , Masculino , Produtos da Carne/toxicidade , Camundongos , Camundongos Endogâmicos ICR , Salsola/metabolismo , Salsola/toxicidade , Sódio/metabolismo , Sódio/toxicidade , SuínosRESUMO
The correlation between chewing and gastric function is best reflected when the same food type is used during both tests. We proposed frankfurter sausage as test food for masticatory performance as it can also be used in gastric emptying test. The suitability of frankfurter sausage to determine masticatory performance, however, has never been examined. To examine the correlations between the median particle size of frankfurter sausage and almonds (as standard test food) after different numbers of chewing cycles. Twenty-seven subjects performed masticatory performance tests by chewing 2 types of test foods, that is, a piece of almond or 5-g frankfurter sausage cubes placed in a sealed latex bag, for 5 and 15 chewing cycles. For each individual, right and left sides were tested separately. Chewed samples obtained from both sides were pooled. Median particle sizes were determined using a multiple sieving method. Spearman's rank correlation was used to examine any correlation between median particle sizes of the 2 test foods after 5 and 15 cycles. Median particle sizes after 5 and 15 cycles were 2.04 ± 0.87 and 0.95 ± 0.58 mm for almonds and 4.16 ± 0.19 and 3.73 ± 0.25 mm for frankfurter sausage, respectively. Significant correlations were observed between the median particle size of chewed frankfurter sausage after 15 cycles and that of chewed almonds after 5 and 15 cycles (r = .76, P < .01 and r = .52, P = .01, respectively). Frankfurter sausage chewed for 15 cycles may be suitable for the determination of masticatory performance in conjunction with gastric emptying test.
Assuntos
Esvaziamento Gástrico/fisiologia , Mastigação/fisiologia , Produtos da Carne , Tamanho da Partícula , Prunus dulcis , Saliva/metabolismo , Adulto , Análise de Variância , Feminino , Filtração/instrumentação , Humanos , Masculino , Reprodutibilidade dos Testes , Propriedades de SuperfícieRESUMO
The objective of the present study was to determine the factors affecting the transfer of foodborne pathogens from inoculated beef fillets to non-inoculated ones, through food processing surfaces. Three different levels of inoculation of beef fillets surface were prepared: a high one of approximately 107 CFU/cm2, a medium one of 105 CFU/cm2 and a low one of 103 CFU/cm2, using mixed-strains of Listeria monocytogenes, or Salmonella enterica Typhimurium, or Escherichia coli O157:H7. The inoculated fillets were then placed on 3 different types of surfaces (stainless steel-SS, polyethylene-PE and wood-WD), for 1 or 15 min. Subsequently, these fillets were removed from the cutting boards and six sequential non-inoculated fillets were placed on the same surfaces for the same period of time. All non-inoculated fillets were contaminated with a progressive reduction trend of each pathogen's population level from the inoculated fillets to the sixth non-inoculated ones that got in contact with the surfaces, and regardless the initial inoculum, a reduction of approximately 2 log CFU/g between inoculated and 1st non-inoculated fillet was observed. S. Typhimurium was transferred at lower mean population (2.39 log CFU/g) to contaminated fillets than E. coli O157:H7 (2.93 log CFU/g), followed by L. monocytogenes (3.12 log CFU/g; P < 0.05). Wooden surfaces (2.77 log CFU/g) enhanced the transfer of bacteria to subsequent fillets compared to other materials (2.66 log CFU/g for SS and PE; P < 0.05). Cross-contamination between meat and surfaces is a multifactorial process strongly depended on the species, initial contamination level, kind of surface, contact time and the number of subsequent fillet, according to analysis of variance. Thus, quantifying the cross-contamination risk associated with various steps of meat processing and food establishments or households can provide a scientific basis for risk management of such products.
Assuntos
Bactérias/isolamento & purificação , Carga Bacteriana , Manipulação de Alimentos , Microbiologia de Alimentos , Carne Vermelha/microbiologia , Bactérias/crescimento & desenvolvimento , Qualidade de Produtos para o Consumidor , Escherichia coli O157/crescimento & desenvolvimento , Escherichia coli O157/isolamento & purificação , Inocuidade dos Alimentos , Indústria de Processamento de Alimentos , Doenças Transmitidas por Alimentos/prevenção & controle , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/isolamento & purificação , Produtos da Carne/microbiologia , Plásticos , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/isolamento & purificação , Aço Inoxidável , Madeira/microbiologiaRESUMO
Foot-and-mouth disease (FMD) is a highly contagious and transboundary viral disease of domesticated and wild cloven-hoofed animals. The present study summarizes the knowledge generated from the epidemiology, diagnosis, and surveillance of the disease in the Maghreb (2014-2015) in assessing its threat to southern European countries. Currently, two serotypes of the FMD virus (O and SAT-2) and four lineages are circulating in the Maghreb region. The introduction of serotype SAT-2 in Libya and Mauritania in 2012 and 2015 respectively sets their neighbors and subsequently south European countries at constant risk of FMD re-emergence. The potential pathways of FMD introduction to southern European countries from the Maghreb are the illegal introduction of infected animals and animal products, particularly meat or meat products carried by refugees.
Assuntos
Vírus da Febre Aftosa , Febre Aftosa/epidemiologia , África do Norte/epidemiologia , Argélia , Animais , Animais Selvagens , Bovinos , Surtos de Doenças , Europa (Continente) , Cabras , Produtos da Carne , Refugiados , Risco , Sorogrupo , Ovinos , TunísiaRESUMO
AIMS: The objective of the study was to investigate the antimicrobial potential of a new SAM(®) polymer poly(TBAMS) as packaging material for meat products. METHODS AND RESULTS: The influence of temperature, time and product factors on the antimicrobial activity of poly(TBAMS) against different bacteria was determined using a modified test method based on the Japanese Industrial Standard 2801:2000. Results showed a significant reduction in bacterial counts on poly(TBAMS) compared with the reference material of several meat-specific micro-organisms after 24 h at 7°C. Bacterial counts of Staphylococcus aureus, Listeria monocytogenes, Lactobacillus spp., Brochothrix thermosphacta and Escherichia coli were reduced by >4·0 log10 units. Pseudomonas fluorescens was less sensitive to poly(TBAMS) within 24 h between 2 and 7°C. Prolonging the storage time to 48 h, however, resulted in an increased reduction rate. Furthermore, antimicrobial activity was also observed if meat components in the form of meat extract, meat juice or bovine serum albumin protein were present. Antimicrobial activity was also achieved if inoculated with mixed cultures. CONCLUSIONS: Poly(TBAMS) showed antimicrobial properties under conditions typical for meat supply chains. SIGNIFICANCE AND IMPACT OF THE STUDY: Poly(TBAMS) bears a high potential to increase safety and shelf life of meat products.
Assuntos
Antibacterianos/farmacologia , Embalagem de Alimentos/instrumentação , Conservantes de Alimentos/farmacologia , Produtos da Carne/microbiologia , Polímeros/farmacologia , Animais , Bovinos , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Lactobacillus/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Estirenos/farmacologia , TemperaturaRESUMO
An immersed-membrane anaerobic membrane bioreactor (AnMBR) achieved 88-95% of COD removal for meat-processing wastewater at organic loading rate (OLR) of 0.4-3.2 kgCOD m(-3) d(-1). Membrane flux was stable for low OLR (0.4 and 1.3 kgCOD m(-3) d(-1)), but irrecoverable fouling occurred at high OLR of 3.2 kgCOD m(-3) d(-1). Methane gas yield of 0.13-0.18 LCH4 g(-1)CODremoved was obtained, which accounted for 33-38% of input COD, the most significant electron sink. Dissolved methane was only 3.4-11% of input COD and consistently over-saturated at all OLR conditions. The least accumulation of dissolved methane (25 mg L(-1) and saturation index 1.3) was found for the highest OLR of 3.2 kgCOD m(-3) d(-1) where biogas production rate was the highest. Energy balances showed that AnMBR produced net energy benefit of 0.16-1.82 kWh m(-3), indicating the possibility of energy-positive food wastewater treatment using AnMBRs.
Assuntos
Biocombustíveis , Reatores Biológicos , Metano/biossíntese , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Indústria Alimentícia , Resíduos Industriais , Produtos da Carne , Membranas Artificiais , Metano/química , Permeabilidade , Temperatura , Eliminação de Resíduos Líquidos/instrumentaçãoRESUMO
A novel fluorescence immunoassay to detect fluoroquinolones in animal-derived foods was developed for the first time by use of upconversion nanoparticles as signal-probe labels. The bioassay system was established by the use of coating-antigen-modified polystyrene particles as immune-sensing probes for separation and anti-norfloxacin monoclonal antibody conjugated with carboxyl-functionalized NaYF4:Yb,Er upconversion nanoparticles which were prepared via a pyrolysis method and a subsequent ligand exchange process as fluorescent-signal probes (emission intensity recorded at 542 nm with excitation at 980 nm). Under optimized conditions, detection of fluoroquinolones was performed easily. The detection limit of this fluorescence immunoassay for norfloxacin, for example, was 10 pg mL(-1), within a wide linear range of 10 pg mL(-1) to 10 ng mL(-1) (R (2) = 0.9959). For specificity analysis, the data obtained indicate this method could be applied in broad-spectrum detection of fluoroquinolones. The recoveries of norfloxacin-spiked animal-derived foods ranged from 82.37 to 132.22 %, with coefficients of variation of 0.24-25.06 %. The extraction procedure was rapid and simple, especially for milk samples, which could be analyzed directly without any pretreatment. In addition, the results obtained with the method were in good agreement with those obtained with commercial ELISA kits. The fluorescence immunoassay was more sensitive, especially with regard to the detection limit in milk samples (0.01 ng mL(-1) for norfloxacin): it was 50-fold more sensitive than commercial ELISA kits (0.5 ng mL(-1) for norfloxacin). The results show the proposed fluorescence immunoassay was facile, sensitive, and interference free, and is an alternative method for the quantitative detection of fluoroquinolone residues in animal-derived foods.
Assuntos
Antibacterianos/isolamento & purificação , Imunofluorescência/métodos , Fluoroquinolonas/isolamento & purificação , Análise de Alimentos/métodos , Nanopartículas/química , Animais , Anticorpos Monoclonais/química , Érbio/química , Transferência Ressonante de Energia de Fluorescência/métodos , Imunofluorescência/normas , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Humanos , Imunoconjugados/química , Limite de Detecção , Produtos da Carne/análise , Leite/química , Nanopartículas/ultraestrutura , Poliestirenos/química , Itérbio/químicaRESUMO
In order to explore the influence of wood types on formation of polycyclic aromatic hydrocarbons (PAHs) in traditional smoked and grilled meat products, the effect of lignin in woods on formation of PAHs was investigated in meat model systems. The results showed that PAHs formation was much dependent on the heating conditions. The addition of lignin led to significantly increased PAHs, which being connected with lignin structure. In comparison, the formation of PAHs was more facilitated by lignin with G structure than that with G/S structure. However, further study of adding lignin precursors demonstrated that lignin precursors with S structure were more favorable to the formation of PAHs than those with G structure. It was proposed that the relative content and activity of G/S structure of lignin in wood played a significant role in the formation of PAHs, which might provide theoretical reference for inhibition of PAHs fundamentally.
Assuntos
Produtos da Carne , Hidrocarbonetos Policíclicos Aromáticos , Produtos da Carne/análise , Lignina , Culinária/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Fumaça , Carne/análiseRESUMO
Plant-based hamburger patties (PHPs) with reduced fat content made using fat replacers will meet the consumption goals of individuals who consume meat alternative products for health. In this study, we developed a dual-alternative food model by analysing the applicability of bacterial cellulose paste (BCP) as a fat replacer and supplementing it in PHPs. BCPs were prepared with solid contents of (w/w; 1.0%, 1.5%, 2.0%, 2.5%, and 3.0%) and compared and analyzed with three types of conventional vegetable [coconut oil, margarine, and shortening (SH)] and animal fats (beef tallow, butter, and lard) for various characteristics (appearance, dimensional stability, hardness level, and rheological properties). According to the results, BCP with a solid content of 3.0% (w/w) had the most similar characteristics to SH. Therefore, using SH as a control fat, PHPs in which 0%, 25%, 50%, 75%, and 100% (w/w) SH were replaced by 3.0% (w/w) BCP were prepared. Analysis of the appearance, instrumental color, diameter reduction, thickness, cooking loss, and texture profile of the PHPs, confirmed that replacement of 25%-50% (w/w) SH with 3.0% (w/w) BCP in the preparation of PHP resulted in i) redder color, ii) better dimensional stability, iii) lower cooking loss, and iv) higher chewiness of the final products. The results of the sensory evaluation showed that the PHPs, with 25%-50% (w/w) SH replaced with 3.0% (w/w) BCP, exhibited no significant differences (p < 0.05) in overall preference scores compared to the full-SH sample. In conclusion, this study demonstrated the potential of BCP as a fat substitute for the production of PHPs.