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1.
Fatty acid content and lipid oxidation products were compared in chicken breast and leg meats derived from birds fed on animal-fat- and vegetable-oil-based diets, supplemented with ginseng prong powder. The first experiment examined polyunsaturated fatty acid (PUFA) content and the formation of primary and secondary lipid oxidation products in meats stored at refrigeration temperatures (4 °C) for up to 10 days, while the second experiment examined similar changes in the poultry meats when frozen stored at −18 °C, for up to six months. Results showed that initial lipid hydroperoxide concentrations increased in both breast and leg meat within the first week of refrigerated storage and also was ongoing during the first three to four months of frozen storage. A higher (p < 0.05) PUFA content in leg meat, especially in broilers fed a vegetable-oil-blended diet, corresponded to greater tendency for generation of primary lipid oxidation products after refrigerated and frozen storage (p < 0.05). The inclusion of powdered ginseng prong in broiler diets significantly inhibited (p < 0.05) secondary lipid oxidation products (e.g., malonaldehyde [MDA]) formation in both stored leg and breast meat, compared to controls. Significant interactions (p < 0.05) were obtained for storage time and inclusion of ginseng against production of primary and secondary lipid oxidation in broiler breast and leg meats from broilers fed PUFA-containing diets. We conclude that including ginseng prong in broiler growing diets represents a viable strategy to control lipid oxidation in refrigerated/cold-stored meat products.  相似文献   

2.
《The Analyst》2002,127(6):859-869
There are uncertainties about the relevance of the nitrogen factors for turkey meat recommended by the Analytical Methods Committee in 1965 when applied to current strains of turkey reared under modern systems of management. As a result, the Nitrogen Factors Sub-Committee has carried out a reappraisal of the chemical composition of turkey meat using two strains of turkey currently used in the UK and Europe. Turkeys representing both sexes at two typical ages for processing were obtained from UK producers. Each bird was dissected to give five samples representing breast, drumstick, thigh, other meat and skin (with associated fat), which were then analysed for fat, moisture, nitrogen, ash and hydroxyproline content. The separate results for each portion were combined mathematically to give figures for whole birds. From these results it was possible to recommend fat-free nitrogen factors for the individual joints and for the entire carcase, with and without skin, for males and females and for type of turkey where known.  相似文献   

3.
In the present study, pomegranate peels, avocado peels, and seed vacuum microwave extraction solid by-products were supplemented in corn silage in order to investigate the effects on meat quality and growth rate in broiler chicken. There were 50 broilers, divided in two groups, treated with experimental or usual feed for 43 days (group A: 25 broilers fed with avocado and pomegranate by-products and group B: 25 broilers fed with corn-silage used as control). The results showed that broiler chickens fed with a diet supplemented with a mixture of pomegranate avocado by-products (group A) showed significant differences in chicken leg meat quality, significantly improving the level of proteins and fatty acids content in breast and leg meat, respectively. More specific ω3 and ω6 fatty acids content were three times higher than in group B. Moreover, a protective effect on the decomposition of polyunsaturated fatty acids, induced by free radicals and presented in chicken meat, is based on the evaluation of lipid peroxidation by measuring thiobarbituric acid reactive substances. Pomegranate peels, avocado peels, and seed by-products appeared to have a slight reduction on meat production, while it was found to improve the qualitative chicken meat characteristics. Regarding the production costs, it was calculated that the corn-silage supplementation, used in this study, lead to a 50% lower cost than the commercial corn-silage used for the breeding of broilers.  相似文献   

4.
A study was made of the distribution and depletion of clopidol residues at different tissue locations in chickens fed with feeds incurred with clopidol. Experiments showed that the residue levels were not identical at 5 different tissue locations in each chicken. The sequence of residue levels from high to low was livers, kidneys, upper breast, lower breast, and leg meat. The maximum residue values after suspension of the drug for 8 h were (mg/kg): livers, 4.600; kidneys, 3.619; upper breast, 1.742; lower breast, 1.641; leg meat, 1.525. The averages were taken after values for 10 chickens were determined. After suspension of the drug for 3 days, >80% residue clopidol was depleted, and the depletion was nearly completed within 7 days. The speed of depletion varied at different tissue locations in each chicken, with the sequence from fast to slow being equivalent to that of the residue levels. Analytical results of 350 samples during 7 days showed that the proposed method is specific for determination of clopidol in chickens.  相似文献   

5.
An investigation of metastable atom bombardment (MAB) ionization mass spectrometry for the fast characterization of mutagenic/carcinogenic heterocyclic aromatic amines (HAAs) formed during heating processes of meats is presented. The aim of our study was to use the selective ionization of MAB to develop a detection method for HAAs in non-purified meat extracts, thus avoiding purification and concentration steps and reducing analysis time. Sample introduction into the MAB ion source was achieved by pyrolysis, allowing the direct and fast insertion of complex food extracts into the mass spectrometer. Analysis conditions were optimized on standard HAAs by using different ionization gases for the MAB process. Metastable nitrogen was selected as the best MAB gas for the analysis of HAAs. Ionization selectivity is shown by the detection of heterocyclic amines in non-purified chicken meat extracts spiked with HAAs. A quantitative approach is also presented by using pyrograms as chromatograms for quantification purposes. HAAs determination using Py-MAB-ToF was finally performed on cooked chicken breast extracts and compared to an LC-APCI-MS/MS method. Although Py-MAB-ToF sensitivity remains to be improved in the present state of development of our prototype device, only 2 h from the cooking were required to obtain quantitative results in good agreement with HAAs concentrations measured by LC-MS/MS in 36 h. Figure Experimental set-up for pyrolysis-MAB-ToF mass spectrometry experiments.  相似文献   

6.
Meat is a rich source of energy that provides high-value animal protein, fats, vitamins, minerals and trace amounts of carbohydrates. Globally, different types of meats are consumed to fulfill nutritional requirements. However, the increasing burden on the livestock industry has triggered the mixing of high-price meat species with low-quality/-price meat. This work aimed to differentiate different meat samples on the basis of metabolites. The metabolic difference between various meat samples was investigated through Nuclear Magnetic Resonance spectroscopy coupled with multivariate data analysis approaches like principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA). In total, 37 metabolites were identified in the gluteal muscle tissues of cow, goat, donkey and chicken using 1H-NMR spectroscopy. PCA was found unable to completely differentiate between meat types, whereas OPLS-DA showed an apparent separation and successfully differentiated samples from all four types of meat. Lactate, creatine, choline, acetate, leucine, isoleucine, valine, formate, carnitine, glutamate, 3-hydroxybutyrate and α-mannose were found as the major discriminating metabolites between white (chicken) and red meat (chevon, beef and donkey). However, inosine, lactate, uracil, carnosine, format, pyruvate, carnitine, creatine and acetate were found responsible for differentiating chevon, beef and donkey meat. The relative quantification of differentiating metabolites was performed using one-way ANOVA and Tukey test. Our results showed that NMR-based metabolomics is a powerful tool for the identification of novel signatures (potential biomarkers) to characterize meats from different sources and could potentially be used for quality control purposes in order to differentiate different meat types.  相似文献   

7.
Bota GM  Harrington PB 《Talanta》2006,68(3):629-635
Biogenic amines are degradation products generated by bacteria in meat products. These amines can indicate bacterial contamination or have a carcinogenic effect to humans consuming spoiled meats; therefore, their rapid detection is essential. Trimethylamine (TMA) is a good target for the detection of biogenic amines because its volatility. TMA was directly detected in meat food products using ion mobility spectrometry (IMS). TMA concentrations were measured in chicken meat juice for a quantitative evaluation of the meat decaying process. The lowest detected TMA concentration in chicken juice was 0.6 ± 0.2 ng and the lowest detected signal for TMA in a standard aqueous solution was 0.6 ng. IMS data were processed using partial least squares (PLS) and Fuzzy rule-building expert system (FuRES). Using these two chemometric methods, trimethylamine concentrations of different days of meat spoilage can be separated, indicating the decaying of meat products. Comparing the two methods, FuRES provided a better classification of different days of meat spoilage.  相似文献   

8.
Two studies were performed in which samples of freeze-dried meat from different species were subjected to replicate analysis by direct probe mass spectromety (DPMS). In the first study samples were obtained from six different muscles from each of three animal species, cattle, chicken and rabbit. In the second study one sample was taken from each of four individual animals from each of six species, cattle, chicken, horse, pig, rabbit and sheep. The spectra were analysed by statistical procedures which determined the ions responsible for the greatest degree of discrimination and the intersample relationships were displayed either as a two-dimensional scatter diagram or non-linear map. The results showed that DPMS was able to differentiate the species of origin of these meats. The reliability of the analysis procedures was tested with further replicates, not included in the original data analysis, which were treated as unknowns and also by using other data analysis techniques which did not require prior knowledge of the groups involved. The test samples fitted extremely well into their respective groups and there was very good agreement between the results from the defined and non-defined data.  相似文献   

9.
顶空气相色谱法快速测定肉及肉制品中乙烯利的残留量   总被引:3,自引:0,他引:3  
利用乙烯利在碱性水溶液中受热能够快速分解成乙烯的特性,建立了顶空气相色谱法快速测定乙烯利在肉及肉制品中残留量的方法。在样品中添加碱液后恒温加热,吸取顶空瓶中的上层气体,采用石英毛细管色谱柱分离,氢火焰离子化检测器测定。该方法的检测限为0.01mg/kg,回收率为90.9%~96.0%,相对标准偏差为3.5%~8.5%。适用于猪肉、牛肉、鸡肉等肉及肉制品中乙烯利残留量的检测。  相似文献   

10.
Analyses of lipid extracts from rabbit meat were carried out by gas chromatography/mass spectrometry (GC/mS) using both electron and chemical ionisation. Ten rabbit carcasses were randomly acquired on the market, from different farms; for each of them muscular tissues from hindleg and breast were analysed. The lipid fractions were extracted, separated and hydrolysed. The fatty acid fractions were derivatised by 2,2-dimethoxypropane. The GC/mS data obtained using electron ionisation (EI) did not allow the complete characterisation of the fatty acid fraction, and for this reason chemical ionisation (CI) was employed using acetonitrile as reactant gas. The data thus obtained show that, for both samples of rabbit tissue, the mean abundance ratio of plasma cholesterol lowering fatty acids and plasma cholesterol elevating fatty acids (PCL/PCE), taken as a parameter describing a desirable lipid uptake, is 2.2 +/- 0.3, significantly higher than the values reported for other meats (0.8-1. 8). These data, together with the high concentration of (n-6) fatty acids, provide a good indication of the high nutritional value of rabbit meat.  相似文献   

11.
Rose MD  Bygrave J  Sharman M 《The Analyst》1999,124(3):289-294
Most food containing drug residues is consumed after cooking or processing, yet surveillance for these residues is almost always conducted on raw tissue. This investigation was to establish the effect of cooking on residues of the nitroimidazole drugs dimetridazole and ronidazole in chicken muscle and egg, to enable dietary intake calculations based on surveillance results. In model aqueous and lipid solutions, dimetridazole and its 2-hydroxy metabolite, which is usually found when residues are present, were relatively stable for times and temperatures normally encountered during standard cooking methods. Ronidazole in hot aqueous solutions, except at acidic pH, was converted into the 2-hydroxy metabolite. Chicken meat and eggs from birds treated with dimetridazole or ronidazole were used to investigate the effects of cooking on food containing these residues. It was apparent that these residues were not destroyed by cooking chicken meat although some of the residue leached from the sample with juices which exuded as it cooked. Residue concentration in egg reduced during cooking by between 14% and 32% of the original concentration.  相似文献   

12.
Verifying the authenticity of food products is essential due to the recent increase in counterfeit meat-containing food products. The existing methods of detection have a number of disadvantages. Therefore, simple, cheap, and sensitive methods for detecting various types of meat are required. In this study, we propose a rapid full-cycle technique to control the chicken or pig adulteration of meat products, including 3 min of crude DNA extraction, 20 min of recombinase polymerase amplification (RPA) at 39 °C, and 10 min of lateral flow assay (LFA) detection. The cytochrome B gene was used in the developed RPA-based test for chicken and pig identification. The selected primers provided specific RPA without DNA nuclease and an additional oligonucleotide probe. As a result, RPA–LFA, based on designed fluorescein- and biotin-labeled primers, detected up to 0.2 pg total DNA per μL, which provided up to 0.001% w/w identification of the target meat component in the composite meat. The RPA–LFA of the chicken and pig meat identification was successfully applied to processed meat products and to meat after heating. The results were confirmed by real-time PCR. Ultimately, the developed analysis is specific and enables the detection of pork and chicken impurities with high accuracy in raw and processed meat mixtures. The proposed rapid full-cycle technique could be adopted for the authentication of other meat products.  相似文献   

13.
The Tepnel Bio Kit for the detection of beef in cooked foods was assessed to determine its validity in demonstrating if food being imported into New Zealand contains beef material. The test suffered no interference from the presence of other common nonbovine species meats accepted as food within New Zealand and it detected beef in cooked samples of mixed meats when the proportion of beef in the mixture was >2 or >1%, depending on other meat species present. The documentation supplied with the kit indicates that the specific proteins it measures in cooked beef are stable to 130 degrees C. This was confirmed in the literature when the kit was used to test meat and bone meal cooked to at least 133 degrees C. However, our results showed these proteins to be much less stable when heated to elevated temperatures in moist food under pressure, and samples containing beef ceased to be positive by the immunoassay test after being autoclaved to 121 degrees C. This suggests that the test may not be able to detect even relatively high levels of beef in low-acid canned foods, which are normally retorted under pressure to approximately 121 degrees C.  相似文献   

14.
兔肉腥味物质的提取与鉴定   总被引:2,自引:0,他引:2  
兔肉腥味(风味)物质与组织结合紧密,使用十二烷基硫酸钠(SDS)可使腥味物质解离释放。应用改进的NPT技术提得未去势与去势兔肉中腥味物质,经气-质联谱比较分析,初步确定中级醛类尤其己醛是兔肉腥味物质的主导成分;两种卤代烷烃(1-氯十二烷和1-溴十三烷)可能是构成兔肉特殊气味的重要成分。  相似文献   

15.
Chicken is the most consumed meat in North America. Concentrations of arsenic in chicken range from μg kg−1 to mg kg−1. However, little is known about the speciation of arsenic in chicken meat. The objective of this research was to develop a method enabling determination of arsenic species in chicken breast muscle. We report here enzyme-enhanced extraction of arsenic species from chicken meat, separation using anion exchange chromatography (HPLC), and simultaneous detection with both inductively coupled plasma mass spectrometry (ICPMS) and electrospray ionization tandem mass spectrometry (ESIMS). We compared the extraction of arsenic species using several proteolytic enzymes: bromelain, papain, pepsin, proteinase K, and trypsin. With the use of papain-assisted extraction, 10 arsenic species were extracted and detected, as compared to 8 detectable arsenic species in the water/methanol extract. The overall extraction efficiency was also improved using a combination of ultrasonication and papain digestion, as compared to the conventional water/methanol extraction. Detection limits were in the range of 1.0–1.8 μg arsenic per kg chicken breast meat (dry weight) for seven arsenic species: arsenobetaine (AsB), inorganic arsenite (AsIII), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), inorganic arsenate (AsV), 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone), and N-acetyl-4-hydroxy-m-arsanilic acid (NAHAA). Analysis of breast meat samples from six chickens receiving feed containing Roxarsone showed the presence of (mean ± standard deviation μg kg−1) AsB (107 ± 4), AsIII (113 ± 7), AsV (7 ± 2), MMA (51 ± 5), DMA (64 ± 6), Roxarsone (18 ± 1), and four unidentified arsenic species (approximate concentration 1–10 μg kg−1).  相似文献   

16.
The purpose of this study was to compare the effect of gamma irradiation on the total bacterial population and the sensory quality of Dakgalbi irradiated before and after cooking. Fresh chicken meat was cut into small pieces and used to prepare Dakgalbi. For the preparation of Dakgalbi cooked with gamma-irradiated chicken meat and sauce (IBC), raw chicken meat and Dakgalbi sauce were irradiated and then stir-fried. For the preparation of Dakgalbi irradiated after cooking with raw chicken meat and sauce (IAC), raw chicken meat and Dakgalbi sauce were first cooked and subsequently irradiated. Under the accelerated storage condition of 35 °C for 7 days, bacteria in IBC were below the detection limit (1 log CFU/g) on day 1 but were detected on day 2 and gradually increased hereafter. In IAC, on the other hand, bacteria were not detected at all. Evaluation of sensory quality also decreased on both samples. However, IAC showed a better trend. Our results indicate that IAC protocol was a more effective method for reducing bacterial growth in Dakgalbi.  相似文献   

17.
The prevention of fraudulent labeling of game meat constitutes an important part of food regulatory control and quality assurance systems. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis based on mitochondrial deoxyribonucleic acid (DNA) was developed for authentication of meats from chamois (Rupicapra rupicapra), pyrenean ibex (Capra pyrenaica), and mouflon (Ovis ammon). Amplification and restriction site analysis of a DNA fragment about 720 base pairs (bp) from the mitochondrial 12S rRNA gene of all analyzed species permitted the selection of Msel and Apol endonucleases for meat speciation. The 12S rRNA restriction profiles obtained allowed the unequivocal identification of chamois, pyrenean ibex, and mouflon/sheep and their differentiation from meats of domestic species such as cattle, goat, and swine. The highly variable mitochondrial D-loop gene was also targeted to attempt discrimination between mouflon and sheep meats. A D-loop region (700-1000 bp) was amplified and sequenced in all game and domestic species analyzed, and a primer set was designed for the selective amplification of a 370 bp DNA fragment from mouflon and sheep. PCR-RFLP analysis with the selected Maell enzyme generated a single electrophoretic profile characteristic for sheep, whereas 3 different fragment patterns were obtained for mouflon meats. Consequently, the PCR-RFLP technique developed can be routinely applied in inspection programs in order to verify the correct labeling of game species.  相似文献   

18.
During the shelf-life, meat undergoes a number of processes that negatively affect the quality of the product, including fatty acid composition. The application of various plant extracts in meat could affect the changes of fatty acids during storage. Thus, the aim of this study was to investigate the effect of various spice and herb extracts on fatty acid composition in raw pork, beef, and chicken meat when stored at 4 °C for 13 days. Based on multivariate statistical analysis, two datasets were extracted from each type of meat. One dataset included samples with allspice, bay leaf, black seed, cardamom, caraway, clove, and nutmeg with the high share of total MUFA (monounsaturated fatty acids) in chicken and pork meat and high MUFA and PUFA (polyunsaturated fatty acids) contribution in beef meat after storage. The second dataset included basil, garlic, onion, oregano, rosemary, and thyme with high PUFA share in chicken and pork meat and high SFA (saturated fatty acids) contribution in beef meat. From the regression analysis, a significant effect of time on fatty acid composition in meat was reported. Generally, the rates of fatty acid changes were dependent on the plant extract incorporated into the meat. The most visible effect of plant extracts was obtained in chicken meat. In chicken meat with plant extracts, the rates of SFA and PUFA changes with time were slower compared to the control sample. In summary, the fatty acid composition of intramuscular fat varied during storage, and the addition of plant extracts significantly affected the rate of these changes, which was dependent on the meat matrix.  相似文献   

19.
In this work, simple microcontact printed gold-wafers were used to make a lectin panel for investigation and discrimination of different meat juices from fresh meat of cattle, chicken, pig, cod, turkey and lamb. Seven different lectins were thus attached to gold surfaces using the streptavidin-biotin method. Lectins recognize and bind specifically to carbohydrate structures present on different proteins. The biorecognition was evaluated with null ellipsometry and the data obtained was related to an internal standard of lactoferrin. The data was evaluated with multivariate data analysis techniques to identify possible discrimination or grouping of data. Scanning ellipsometry was used for visualization of the binding pattern of the lectins and the meat juice proteins. The two-dimensional images obtained could be used to visualize the protein distribution, furthermore, to exclude anomalies. The results showed that the different meat juices from the six different species: cattle, chicken, pig, cod, turkey and lamb could be discriminated from each other. The results showed to be more repetitive for the mammalian meat juices. Using a simple model based on an artificial neuronal net, it was also possible to classify meat juices from the mammals investigated.  相似文献   

20.
In response to reference material needs expressed by the food industry and government regulators, the National Institute of Standards and Technology (NIST) has developed a new Standard Reference Material (SRM) consisting of a canned meat product with certified and reference values for a large number of constituents. SRM 1546 Meat Homogenate consists of a mixture of finely ground pork and chicken prepared and canned by a commercial process. NIST determined the concentration levels of cholesterol, sodium, calcium, iron, and seven fatty acids in this SRM using well defined methods and procedures. These analytes as well as 34 other constituents or properties were determined in an interlaboratory comparison exercise involving 21 laboratories, most of which are associated with the National Food Processors Association (NFPA) Food Industry Analytical Chemists Subcommittee (FIACS). From statistical analysis of the data, NIST assigned certified concentrations for the eleven analytes measured at NIST and reference concentrations for the proximates, six additional fatty acids, seven minerals, and seven water-soluble vitamins. Information values without uncertainties are provided for the concentrations of six additional constituents for which the uncertainties could not adequately be assessed. SRM 1546 will provide laboratories with a means to evaluate the accuracy of the methods they use to assign nutrient levels to processed meats and similar products.  相似文献   

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