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In order to investigate PCB and PCDD/F concentrations and potential human health risk a study has been conducted in meat samples (beef, pork, chicken and turkey) purchased from Italian supermarkets. PCBs were dominant (41.8-77.7 ng g -1 l.w.) with respect to PCDD/Fs (20.1-91.1 pg g -1 l.w.). The levels were variable and largely dependent upon the type of meat. Accumulation pattern showed a distribution typically reported for meat. PCBs tended to decrease from lowest to highest congeners, while for PCDD/Fs the concentration profile was dominated by highly chlorinated dioxins and furans. Concentrations of PCDD/Fs plus dl-PCBs and indicator PCBs exceeding the EU maximum permissible levels were found in 23.3% and 53.3% of the samples, respectively. Exposure estimates to PCDD/Fs plus dl-PCBs (0.08-4.16 pg WHO-TEQs kg -1 b.w. w. -1 ) were within the new limit proposed by the EFSA's expert panel, except for pork sausage, showing a twofold higher value. Concerning the exposure derived from indicator PCBs, the maximum level set by different European countries (10 ng kg -1 b.w. d. -1 ) was surpassed solely via consumption of pork sausage (17.22 ng kg -1 b.w. d. -1 ), thought also the estimated intake from hamburger consumption (6.88 ng kg -1 b.w. d. -1 ) merits attention being close to guideline limit., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A compilation of volatile N -nitrosamine levels in processed (e.g., cured, canned, smoked) meat and poultry products is presented. Over 1800 samples of processed meat products including bacon, ham, salami, sausage, and various other processed meat and poultry products have been examined for the presence of eight volatile N -nitrosamines. The database compiled from the literature is based on 25 references published for the period of 1985 to 2018 from 14 countries. N -nitrosodimethylamine (NDMA), N -nitrosopiperidine (NPIP), and N -nitrosopyrrolidine (NPYR), are the most frequently identified volatile N -nitrosamines occurring in processed meat and poultry products. N-nitrosodiethylamine (NDEA), and N -nitrosodibutylamine (NDBA) are also frequently observed to a lesser extent. The processed meat and poultry products with the highest levels of volatile N -nitrosamines were pork (fried, fat only eaten), poultry (fried), poultry (spiced, grilled), and bacon (fried).

Nowadays people tend to include more meat in their diet thanks to the improvement in standards of living as well as an increase in awareness of meat nutritive values. To ensure public health, therefore, there is a need for a rise in worldwide meat production and consumption. Further attention is also required as to how the safety and the quality of meat production process should be assessed. Classical methods of meat quality assessment, however, have some disadvantages; expensive and time-consuming. This study intends to introduce an alternative method known as Computer Vision (CV) for the assessment of various quality parameters of muscle foods. CV has several advantages over the traditional methods. It is non-destructive, easy, and quick, hence, more efficient in meat quality assessments. This study aims to investigate different quality characteristics of some muscle foods using CV. It closes with a discussion on the future challenges and expected opportunities of the practical application of CV in the meat industry., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Discrimination and classification of eight strains related to meat spoilage and pathogenic microorganisms commonly found in poultry meat were successfully carried out using two dispersive Raman spectrometers (Microscope and Portable Fiber-Optic systems) in combination with chemometric methods. Principal components analysis (PCA) and multi-class support vector machines (MC-SVM) were applied to develop discrimination and classification models. These models were certified using validation data sets which were successfully assigned to the correct bacterial species and even to the right strain. The discrimination of bacteria down to the strain level was performed for the pre-processed spectral data using a 3-stage model based on PCA. The spectral features and differences among the species on which the discrimination was based were clarified through PCA loadings. In MC-SVM the pre-processed spectral data was subjected to PCA and utilized to build a classification model. When using the first two components, the accuracy of the MC-SVM model was 97.64% and 93.23% for the validation data collected by the Raman Microscope and the Portable Fiber-Optic Raman system, respectively. The accuracy reached 100% for the validation data by using the first eight and ten PC's from the data collected by Raman Microscope and by Portable Fiber-Optic Raman system, respectively. The results reflect the strong discriminative power and the high performance of the developed models, the suitability of the pre-processing method used in this study and that the low accuracy of the Portable Fiber-Optic Raman system does not adversely affect the discriminative power of the developed models., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Covalent organic framework TpBD was grafted on stainless steel wire with polydopamine as a linker. The fabricated TpBD bonded stainless steel wire was used as the solid-phase microextraction fiber to extract sixteen polycyclic aromatic hydrocarbons (PAHs) for subsequent GC-MS/MS determination in grilled meat samples. The developed method gave the limits of detection (S/N = 3) from 0.02 (pyrene)-1.66 (naphthalene) ng L -1 and enhancement factors from 1069 (naphthalene)-10879 (benz(a)anthracene). The relative standard deviations (RSDs) for intra-day and inter-day study are in the range of 2.6%-8.5% and 4.5%-9.4%, respectively. The fiber-to-fiber RSDs for three parallel prepared fibers were 5.3%-10.0%. One TpBD bonded fiber can stand at least 200 cycles without significant loss of extraction efficiency. The developed method was successfully applied for the determination of trace PAHs in grilled meat samples with recoveries from 85.1% to 102.8%., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Creatine is a nitrogenous compound naturally occurring in animal tissues and is obtained from dietary animal protein or de novo synthesis from guanidinoacetic acid (GAA). The dietary supply of this semi-essential nutrient could be adversely compromised when feeding purely vegetable-based diets. The objective of this experiment was to evaluate the effects of GAA supplementation in broilers fed corn-based diets with or without the inclusion of poultry by-products (PBP) on live performance, carcass and cut up yields, meat quality, pectoral muscle myopathies, differential blood count, blood clinical chemistry, serum GAA and its metabolites. The treatments consisted of PBP inclusion in the diets at 0 and 5%, with or without GAA supplementation (0 or 0.06%). A total of 1,280 one-d-old male Ross 708 broiler chicks were randomly placed in 64 floor pens with 16 replicates per treatment combination. At 0, 14, 35, 48, and 55 d, pen BW and feed intake were recorded. BW gain and FCR were calculated at the end of each phase. Individual BW was obtained at 55 d and one broiler per pen was selected for blood collection. Additionally, four broilers per pen were selected (including the chicken for blood collection) for processing. Data were analyzed as a randomized complete block design in a 2 × 2 factorial arrangement with PBP and GAA supplementation as main effects. An improvement (P < 0.05) on FCR of 0.019 (g:g) was detected at 55 d due to GAA supplementation. The probability of having breast meat with low severity of wooden breast (score 2) was increased (P < 0.05) by GAA inclusion in diets without PBP. An interaction effect (P < 0.05) was detected on GAA concentration in blood. The supplementation with GAA and PBP inclusion resulted in higher (P < 0.05) GAA serum concentration. Generally, meat quality parameters were not affected by GAA. In conclusion, GAA supplementation improved FCR regardless of dietary PBP and reduced wooden breast severity by increasing score 2 in diets without PBP.

Background: Sodium-reduced packaged food products are increasingly available to consumers; however, it is not clear whether they are suitable for inclusion in a potassium-reduced diet. For individuals with impaired renal potassium excretion caused by chronic kidney disease and for those taking certain medications that interfere with the rennin-angiotensin aldosterone axis, the need to limit dietary potassium is important in view of the risk for development of hyperkalemia and fatal cardiac arrhythmias., Objective: The primary objective of this study was to determine the impact of the reduction of sodium in packaged meat and poultry products (MPPs) on the content of potassium and phosphorus from food additives., Design: This was a cross-sectional study comparing chemically analyzed MPPs (n=38, n=19 original, n=19 sodium-reduced), selected from the top three grocery chains in Canada, based on market share sales. All MPPs with a package label containing a reduced sodium content claim together with their non-sodium-reduced packaged MPP counterparts were selected for analysis. The protein, sodium, phosphorus, and potassium contents of sodium-reduced MPPs and the non-sodium-reduced (original) MPP counterparts were chemically analyzed according to the Association of Analytical Communities official methods 992.15 and 984.27 and compared by using a paired t test. The frequency of phosphorus and potassium additives appearing on the product labels' ingredient lists were compared between groups by using McNemar's test., Results: Sodium-reduced MPPs (n=19) contained 44% more potassium (mg/100 g) than their non-sodium-reduced counterparts (n=19) (mean difference [95% CI): 184 [90-279]; P=0.001). The potassium content of sodium-reduced MPPs varied widely and ranged from 210 to 1,500 mg/100 g. Potassium-containing additives were found on the ingredient list in 63% of the sodium-reduced products and 26% of the non-sodium-reduced products (P=0.02). Sodium-reduced MPPs contained 38% less sodium (mg/100 g) than their non-sodium-reduced counterparts (mean difference [95% CI]: 486 [334-638]; P<0.001). The amounts of phosphorus and protein, as well as the frequency of phosphorus additives appearing on the product label ingredient list, did not significantly differ between the two groups., Conclusions: Potassium additives are frequently added to sodium-reduced MPPs in amounts that significantly contribute to the potassium load for patients with impaired renal handling of potassium caused by chronic kidney disease and certain medications. Patients requiring potassium restriction should be counseled to be cautious regarding the potassium content of sodium-reduced MPPs and encouraged to make food choices accordingly., (Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)

Synthetic preservatives are widely used by the food industry to control the growth of spoilage and pathogenic microorganisms and to inhibit the process of lipid oxidation extending the shelf-life, quality and safety of food products. However, consumer's preference for natural food additives and concern regarding the safety of synthetic preservatives prompted the food industry to look for natural alternatives. Natural antimicrobials, including plant extracts and their essential oils, enzymes, peptides, bacteriocins, bacteriophages, and fermented ingredients have all been shown to have the potential for use as alternatives to chemical antimicrobials. Some spices, herbs and other plant extracts were also reported to be strong antioxidants. The antimicrobial/antioxidant activities of some plant extracts and/or their essential oils are mainly due to the presence of some major bioactive compounds, including phenolic acids, terpenes, aldehydes, and flavonoids. The proposed mechanisms of action of these natural preservatives are reported. An overview of the research done on the direct incorporation of natural preservatives agents into meat and poultry products as well as fruit and vegetables to extend their shelf-life is presented. The development of edible packaging materials containing natural preservatives is growing and their applications in selected food products are also presented in this review.

Umami taste is an important part to the taste of chicken. To isolate and identify non-volatile umami compounds, fractions from chicken soup and hydrolysate were prepared and analyzed. Amino acids were analyzed by amino acid analyzer. Organic acids and nucleotides were determined by ultra-performance liquid chromatography. Separation procedures utilizing ultrafiltration, Sephadex G-15 and reversed-phase high-performance liquid chromatography were used to isolate umami taste peptides. Combined with sensory evaluation and LC-Q-TOF-MS, the amino acid sequences of 12 oligopeptides were determined. The amount of taste compounds was higher in chicken enzymatic hydrolysate than that of chicken soup. Eight oligopeptides from chicken enzymatic hydrolysate were identified, including Ala-Asp, Ala-Met, His-Ser, Val-Glu, Ala-Glu, Asp-Ala-Gly, Glu-Asp and Ala-Glu-Ala. Four oligopeptides from chicken soup were identified, including Val-Thr, Ala-His, Ala-Phe and Thr-Glu., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants whose use has contaminated foods and caused subsequent human exposures. To address the issue of possible human exposure, samples from a 2012-13 US meat and poultry (beef, pork, chicken, turkey) study were analysed for seven PBDEs. The mean summed concentrations of the seven BDE congeners (ΣPBDE) from beef, pork, chicken and turkey were 0.40, 0.36, 0.19, and 0.76 ng g -1 lipid weight (lw). The range of ΣPBDEs for all meat classes was 0.01-15.78 ng g -1 lw. A comparison of this study with a 2007-08 study revealed a decline in the median ΣPBDEs for all four meat classes, a reduction of 25.9% to 70.0%, with pork, chicken and turkey PBDE residues being statistically lower relative to the 2007-08 study. BDEs 47 and 99 contributed the most to the ΣPBDE concentrations, indicating likely animal exposures to the penta-BDE formulation. Based on the reported data an estimate of US consumer daily intake of PBDEs from meat and poultry was 6.42 ng day -1 .

The aim of this work was to develop a new system based on impedance spectroscopy to assess the heat treatment of previously cooked chicken meat by two experiments; in the first, samples were cooked at different temperatures (from 60 to 90 ℃) until core temperature of the meat reached the water bath temperature. In the second approach, temperature was 80 ℃ and the samples were cooked for different times (from 5 to 55 min). Impedance was measured once samples had cooled. The examined processing parameters were the maximum temperature reached in thermal centre of the samples, weight loss, moisture and the integral of the temperature profile during the cooking-cooling process. The correlation between the processing parameters and impedance was studied by partial least square regressions. The models were able to predict the studied parameters. Our results are essential for developing a new system to control the technological, sensory and safety aspects of cooked meat products on the whole meat processing line.

In order to analyze the composition of fatty acids employing gas chromatography as the separation method, a derivatization of lipids using esterification and transesterification reactions is needed. The methodologies currently available are time consuming and use large amounts of sample and reagents. Thus, this work proposes a new procedure to carry out the derivatization of fatty acids without the need for prior extraction of lipids. The use of small amounts of sample (100mg) allows the analysis to be performed in specific parts of animals, in most cases without having them slaughtered. Another benefit is the use of small amounts of reagents (only 2mL of NaOH/Methanol and H2SO4/Methanol). The use of an experimental design procedure (Design Expert software) allows the optimization of the alkaline and acid reaction times. The procedure was validated for five minutes in both steps. The method was validated for bovine fat, beef, chicken, pork, fish and shrimp meats. The results for the merit figures of accuracy (from 101.07% to 109.18%), precision (RSDintra-day (from 0.65 to 3.93%), RSDinter-day (from 1.57 to 5.22%)), linearity (R(2)=0.9864) and robustness confirmed that the new method is satisfactory within the linear range of 2-30% of lipids in the sample. Besides the benefits of minimizing the amount of samples and reagents, the procedure enables gas chromatography sample preparation in a very short time compared with traditional procedures., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The aim of this trial was to study the effects of replacing yellow corn (C) with condensed tannin-free sorghum (S) during the finishing period (F period; age 53 to 79 d) and/or overfeeding period (O period; age 80 to 91 d) on the performance of overfed mule ducks. 192 ducks were divided into 4 groups (48 in each) differing in the cereal (yellow corn or sorghum) included in the diet given during the F and/or the O periods, using a 2 × 2 factorial arrangement of treatments : SS, SC, CS, CC. At the end of the O period, the birds were slaughtered after 10 h of fasting to measure foie gras and magret qualities. Mortality (1%; P > 0.05) and weight gain (2,030 g; P > 0.05) during the O period were similar in the 4 groups. At the end of the O period, birds overfed with sorghum had foie gras that was heavier (723 vs. 694 g in CS+SS vs. CC+SC, respectively; P < 0.05) and less yellow (24.40 vs. 38.59 for b* in CS+SS vs. CC+SC, respectively; P < 0.001) than birds overfed with corn. Fat loss during foie gras cooking was similar in the 4 groups (18%; P > 0.05), but the foie gras was less yellow in birds overfed with sorghum (14.84 vs. 26.01 for b* in CS+SS vs. CC+SC, respectively; P < 0.001). Weight of magret was similar in the 4 groups (491 g, P > 0.05) but the color of the breast muscle and skin of magret was less yellow in birds overfed with sorghum compared with corn (12.26 vs. 12.92 and 13.84 vs. 18.30 in CS+SS vs. CC+SC, respectively; P < 0.001). In conclusion, the replacement of yellow corn with sorghum during finishing and/or overfeeding is possible and useful in a mule duck foie gras production system because it increases foie gras weight without decreasing the weight of magret However, it changes the quality of the products, mainly their color., (© 2016 Poultry Science Association Inc.)

Antimicrobial agents are added to poultry products after slaughter to prevent the growth of pathogenic and spoilage microorganisms and to extend the shelf-life of these products. Antimicrobials can be either natural or chemical, which may affect the sensory attributes at elevated concentrations, such as surface color, odor, flavor, taste, and texture of the poultry products. Thus, when selecting antimicrobials for use in poultry processing, it is vital to consider the antimicrobial-induced changes in sensory aspects from the consumers' perspectives. In spite of its importance, there has been no systematic review on the influences of antimicrobials on sensory aspects of poultry products. This paper reviews the major antimicrobial agents used in the poultry processing industry and their effects on sensory aspects of the poultry products., (© 2015 Poultry Science Association Inc.)

Using primers and fluorescent probes specific for the most common food-borne Campylobacter species (Campylobacter jejuni and Campylobacter coli), we developed a multiplex, most probable number (MPN) assay using quantitative PCR (qPCR) as the determinant for binomial detection: i.e., number of p positive pathogen growth responses out of n = 6 observations each of 4 mL (V) per dilution. Working with media washes of thrice frozen-thawed chicken pieces which had been spiked with known levels of C. jejuni and C. coli, we found that about 20% of the experiments had a significant amount of error in the form of either greater than 25% MPN calculation error (Δε) and/or a low apparent recovery rate (R less than 1 = MPN observed ÷ CFU spiked). Assuming such errors were exacerbated by an excessively small n, we examined computer-generated MPN enumeration data from the standpoint of stochastic sampling error (Δ) and found that such binomial-based assays behaved identically to Poisson-based methods (e.g., counting data) except that fewer technical replicates (n) appeared to be required for the same number of cells per test volume (μ). This result implies that the qPCR detection-based MPN protocol discussed herein should accurately enumerate a test population with a μ ≥ 1 using n = 6 observations per dilution. For our protocol, this equates to ≥ 8 cells per 400-500 g of sampled product. Based on this analysis, the error rate we saw in spiked experiments (where μ >> 1) implied a non-stochastic source. In other experiments we present evidence that this source was, at least in part, related to the cell concentration step (i.e., centrifugation). We also demonstrate that the error rate lessened (from ~38% to ~13%) at lower Campylobacter levels (μ ≤ 40) as would most likely exist in nature. Using this protocol, we were able to quantify 14 to 1,226 MPN per 450 g of naturally contaminated chicken for skinless pieces and 11 to 244 MPN per 450 g for wings, breasts, legs, and thighs (skin on) whereupon about 50% of the 29 samples tested negative for both species. Four of these chicken wash samples did have substantially lower Campylobacter levels (1 to 6 MPN per 450 g) which might be better enumerated using a larger n. However, we established that the limit of quantification of this protocol diminishes for n > 6 because one is ever more diluting the sample, or lessening V, to achieve the requisite n.

Objective: In 1976, the Royal College of Physicians and the British Cardiac Society recommended eating less fatty red meat and more poultry instead because it was lean. However, the situation has changed since that time, with a striking increase in fat content of the standard broiler chicken. The aim of the present study was to report a snapshot of data on fat in chickens now sold to the public., Design: Samples were obtained randomly between 2004 and 2008 from UK supermarkets, farm shops and a football club. The amount of chicken fat was estimated by emulsification and chloroform/methanol extraction., Setting: Food sold in supermarkets and farms in England., Subjects: Chicken samples., Results: The fat energy exceeded that of protein. There has been a loss of n-3 fatty acids. The n-6:n-3 ratio was found to be as high as 9:1, as opposed to the recommendation of about 2:1. Moreover, the TAG level in the meat and whole bird mostly exceeded the proportion of phospholipids, which should be the higher for muscle function. The n-3 fatty acid docosapentaenoic acid (DPA, 22 : 5n-3) was in excess of DHA (22 : 6n-3). Previous analyses had, as usual for birds, more DHA than DPA., Conclusions: Traditional poultry and eggs were one of the few land-based sources of long-chain n-3 fatty acids, especially DHA, which is synthesized from its parent precursor in the green food chain. In view of the obesity epidemic, chickens that provide several times the fat energy compared with protein seem illogical. This type of chicken husbandry needs to be reviewed with regard to its implications for animal welfare and human nutrition.

Background: Dietary intake of phosphorus is derived largely from protein sources and is a critical determinant of phosphorus balance in patients with chronic kidney disease. Information about the phosphorus content of prepared foods generally is unavailable, but it is believed to contribute significantly to the phosphorus burden of patients with chronic kidney disease., Design: Analysis of dietary components., Setting: We measured the phosphorus content of 44 food products, including 30 refrigerated or frozen precooked meat, poultry, and fish items, generally national brands., Outcomes: Measured and reported phosphorus content of foods., Measurements: Phosphorus by using Association of Analytical Communities official method 984.27; protein by using Association of Analytical Communities official method 990.03., Results: We found that the ratio of phosphorus to protein content in these items ranged from 6.1 to 21.5 mg of phosphorus per 1 g of protein. The mean ratio in the 19 food products with a label listing phosphorus as an additive was 14.6 mg/g compared with 9.0 mg/g in the 11 items without listed phosphorus. The phosphorus content of only 1 precooked food product was available in a widely used dietary database., Limitations: Results cannot be extrapolated to other products. Manufacturers also may alter the phosphorus content of foods at any time. Protein content was not directly measured for all foods., Conclusion: Better reporting of phosphorus content of foods by manufacturers could result in improved dietary phosphorus control without risk of protein malnutrition.

A quick and cost-effective technique of sample preparation followed by a reversed-phase high performance liquid chromatography under "organic solvent-free" (=100% aqueous) conditions for the simultaneous quantifying of sulfadimethoxine (SDM) and its metabolites, 6-hydroxy SDM (6-OH) and N(4)-acetyl SDM (N(4)-Ac), in chicken muscle is presented. Analysis by HPLC with photo-diode array detector was performed using a short C1 column with an isocratic 0.04 mol/l citric acid mobile phase. The method was validated by the analyses of spiked chicken muscle samples, resulting recoveries (> or =84%; relative standard deviations < or =6%), analytical total time (<1/2 h/sample, where a batch of 12 samples in 4 h), and limits of quantitation (< or =0.1 microg/g). The decision limits and detection capability were 0.019-0.106 and 0.054-0.112 microg/g, respectively. No organic solvents were used at all.

In 2003-2004, the U.S. Department of Agriculture Food Safety and Inspection Service (FSIS) conducted an exploratory assessment to determine the occurrence and levels of cadmium and lead in randomly collected samples of kidney, liver, and muscle tissues of mature chickens, boars/stags, dairy cows, and heifers. The data generated in the study were qualitatively compared to data that FSIS gathered in a 1985-1986 study in order to identify trends in the levels of cadmium and lead in meat and poultry products. The exploratory assessment was necessary to verify that Hazard Analysis and Critical Control Point plans and efforts to control exposure to these heavy metals are effective and result in products that meet U.S. export requirements. A comparison of data from the two FSIS studies suggests that the incidence and levels of cadmium and lead in different slaughter classes have remained stable since the first study was conducted in 1985-1986. This study was conducted to fulfill FSIS mandate to ensure that meat, poultry, and egg products entering commerce in the United States are free of adulterants, including elevated levels of environmental contaminants such as cadmium and lead.

To obtain information on dioxin levels in the human diet, the Food Safety and Inspection Service of the United States Department of Agriculture recently determined levels of dioxin-like compounds (dioxins/dibenzofurans/PCBs) in four major slaughter classes (steers and heifers, market hogs, young chickens, and young turkeys) that comprise over 90% of the meat and poultry production in the United States. The data were analyzed and compared to data from smaller surveys carried out from 1994 to 1996. These surveys were conducted by different laboratories nearly 10 years apart, so a direct comparison of the data was not straightforward. Three approaches were taken: (1) comparison with nondetects set to zero, (2) comparison with nondetects set to half the limit of detection, and (3) comparison applying the earlier surveys' limits of detection to the newer data. The data analyses indicated that dioxin levels appear to have declined in three of the four slaughter classes, with young chickens, market hogs, and young turkeys declining 20-80%, while any declines in cattle dioxin levels, if real, are less than those observed in the other slaughter classes. Further study is needed to examine factors that might explain the differences in dioxin levels and distribution profiles in the four slaughter classes. A small number of market hog and steers/ heifers samples had dioxin toxic equivalency levels (TEQs) greater than 2 pg/g lipid weight. Follow-up investigations for those samples indicated a common source for the market hog samples (a dioxin-contaminated mineral supplement), but no commonality was found for the steers/ heifers samples.

The aim of this study was to determine the levels of lead and cadmium in chicken, pork, beef, lamb and turkey samples (both meat and meat products), collected in the island of Tenerife (Spain). Lead and cadmium were measured by graphite furnace atomic absorption spectrometry (GFAAS). Mean concentrations of lead and cadmium were 6.94 and 1.68 microg kg(-1) in chicken meat, 5.00 and 5.49 microg kg(-1) in pork meat, 1.91 and 1.90 microg kg(-1) in beef meat and 1.35 and 1.22 microg kg(-1) in lamb meat samples, respectively. Lead was below the detection limit in turkey samples and mean cadmium concentration was 5.49 microg kg(-1). Mean concentrations of lead and cadmium in chicken meat product samples were 3.16 and 4.15 microg kg(-1), 4.89 and 6.50 microg kg(-1) in pork meat product, 6.72 and 4.76 microg kg(-1) in beef meat product and 9.12 and 5.98 microg kg(-1) in turkey meat product samples, respectively. The percentage contribution of the two considered metals to provisional tolerable weekly intake (PTWI) was calculated for meat and meat products. Statistically significant differences were found for lead content in meats between the chicken and pork groups and the turkey and beef groups, whereas for cadmium concentrations in meats, significant differences were observed between the turkey and chicken, beef and lamb groups. In meat products, no clear differences were observed for lead and cadmium between the various groups.

Modeling of broiler chicken supply-chain economics depends on robust biological models of growth and yield of broiler chickens. In this paper, 8 dynamic nonlinear broiler carcass and carcass part yield models were evaluated statistically for their suitability for predicting weights of carcass parts. The analysis employed 4 sigmoidal (S) models (Gompertz, modified Gompertz, Richards, and Lopez) describing carcass part weight as a function of age, as well as 3 diminishing returns (DR) models (Lopez, Mitscherlich, and log linear), and a log-linear proportional yield (PY) model, which describe carcass part yield and weight, respectively, as a proportion of feather- and fat-free empty body mass (FFEBM). Three S models with a flexible point of inflection were better able to predict carcass part weights than a fixed point of inflection Gompertz model and, in general, the DR models. The log-linear models were the only models that converged in 100% of the evaluations. The allometric PY model predicted weights for most carcass parts with the smallest degree of error and with substantially less bias than the DR log-linear model. Estimates of the coefficients for the log-linear PY model are included for 12 key carcass parts. Estimates of carcass chemical composition are presented for the log-linear PY model.

Effects of abusive storage conditions on the quality of fresh chicken were studied by detecting DNA damage to breast fillets and liver with the neutral comet assay. Chilled samples were kept at 4 degrees C for prolonged periods, whereas frozen samples were exposed to temperatures of 4 degrees C, representing inadvertent thawing, and 20 degrees C, representing extreme abuse in the distribution chain. Comets' mean tail moment distributions reflected the increasing patterns of DNA damage, but the differences of values between close levels of treatment were sometimes insignificant. The design of the DNA damage index, integrating the distribution of mean tail moments over three trials, provided values significantly different, which allowed a more precise discrimination between samples according to the treatment levels. Considering the background level of DNA damage in control cells, a DNA damage index value of 50 microm was set as a limit for the detection of abusive storage. Temperature abuse could be detected after 7 and 22 h of exposure at 4 degrees C for liver and breast, respectively. These durations were by far shorter (1.5 and 2.5 h, respectively) when the temperature was increased to 20 degrees C. As for chilled storage, its damaging effects could be detected after 1.5 and 2.5 days for liver and breast, respectively. Liver cells were more sensitive to abusive conditions than breast muscle cells. The comet assay's detection limit was applicable to samples that were still considered of good quality with regard to the microbiological shelf life, thereby showing its high sensitivity as a rapid test for assessing the quality of fresh chicken.

The influence of Bifezh (a hexacyanoferrate compound as veterinary feed additive) on the transfer of (137)Cs to meat was investigated in broiler chickens after application of an artificially contaminated feed mixture. The reduction factors reached 2.23 and 8.46 for single and multiple (137)Cs administration, respectively. The elimination rate of (137)Cs in the decontamination period was only slightly increased by Bifezh. The reduction effect of Bifezh was considerably and positively limited by various amounts of the additive during both radiocaesium accumulation and decontamination. No significant differences in the reduction effect between breast and thigh meat were observed. In conclusion, the hexacyanoferrate-cellulose binder Bifezh can be recommended as an alternative chemical measure for reducing (137)Cs contamination of broiler chicken meat, although administration rates may need to be enhanced over those currently recommended.

The dietary and post-mortem uses of oregano oil in turkeys to inhibit development of lipid oxidation in breast and thigh meat during refrigerated storage were investigated. Using minced meat, patties were prepared from turkey meat post-mortem added with either 200 mg oregano oil or alpha-tocopherol/kg, meat from turkeys dietary supplemented with either 200 mg oregano oil or alpha-tocopheryl acetate/kg feed, and control meat. All patties were cooked, placed in a refrigerated cabinet at 4 degrees C, and lipid oxidation was assessed by monitoring malondialdehyde formation after 3, 6 and 9 days of storage. Treatments significantly (P<0.05) retarded lipid oxidation in both breast and thigh meat patties at all storage times compared with controls. The dietary supplementation of either oregano oil or alpha-tocopheryl acetate exhibited the highest antioxidative activity compared with the other treatments. Post-mortem addition of either oregano oil or alpha-tocopherol to the minced meat also retarded lipid oxidation in the prepared patties compared with controls; however, this effect was inferior to that of the dietary supplementation even though the post-mortem alpha-tocopherol supplemented meat contained 90-fold more alpha-tocopherol than patties from the dietary supplemented meat. Thigh meat was more susceptible to oxidation than breast meat, although the former contained alpha-tocopherol at markedly higher levels. Supplementing the diet with 200 mg oregano oil/kg, alpha-tocopherol levels in the breast and thigh meat significantly (P<0.05) increased compared with control. This increase could not be attributed to the alpha-tocopherol already present in the oregano oil since post-mortem addition of oregano oil to control breast and thigh meat at the same dose could not actually increase the alpha-tocopherol concentrations.

The measurement of gamma-glutamyl-beta-alanylhistidine isopeptide in the macromolecular fraction of various commercial meat extracts indicated that all of the commercial meat extracts tested contained the isopeptide, in concentrations ranging from 0.04 to 0.87 micromol/g of dry matter. This variation was suggested to be due to the differences between the processes of extraction and the differences in the initial amounts of carnosine. A positive correlation between the content of gamma-glutamyl-beta-alanylhistidine and the color of the macromolecular fraction was observed. These results suggested that gamma-glutamyl-beta-alanylhistidine is widely distributed in meat products and that the content can be used as an index of protein denaturation during the heating process.

Detection of species adulteration in ground meat products is important for consumer protection and food-labeling law enforcement. This study was conducted to develop monoclonal antibodies (MAbs) that can be used in an enzyme-linked immunosorbent assay (ELISA) for rapid detection of any cooked mammalian meats in cooked poultry products. Soluble muscle proteins extracted from cooked pork (heated at 100 degrees C for 15 min) were used as the antigen to immunized mice for developing the MAb. One that was developed, MAb 2F8 (IgG2b class), strongly reacted with cooked meat of five mammalian species (beef cattle, hogs, sheep, horse, and deer) but did not react with any cooked poultry (chicken, turkey, and duck) or raw meats. At least 0.5% by weight of pork, beef, lamb, and horse meats in a chicken-based mixture could not detect using the indirect ELISA with MAb 2F8. The MAb 2F8 is useful in a single initial screening test to detect the presence of five nonpoultry meat adulterants in cooked poultry products.

In situ, digestion, and growth studies were conducted to evaluate four meat and bone meals and six poultry by-product meals as sources of escape protein and to predict the first-limiting amino acid for growing calves. Escape protein values, determined by 12-h in situ incubation, ranged from 41.7 to 51.0% of CP for meat and bone meals; poultry by-product meals ranged from 32.0 to 39.8%. True protein digestion in the gastrointestinal tract of lambs differed among protein sources (P < .05), ranging from 79 to 95%. In each of three growth trials, 60 steers (258 +/- 24, 241 +/- 23, and 230 +/- 16 kg for Trials 1, 2, and 3, respectively) were supplemented with 4 of the 10 protein sources along with a urea supplement. Protein sources were fed at 30, 40, 50, and 60% of the supplemental CP, with urea supplying the remainder. Protein efficiency differed among treatments ( P < .10), ranging from .61 to 1.55. Amino acid composition was determined for each protein source, and the individual metabolizable amino acids were regressed on the protein efficiency values. Escape protein values were correlated (R2 = .75) with protein efficiency but had a negative slope. Metabolizable methionine was the only amino acid moderately correlated (R2 = .40, slope = 1.9) to protein efficiency, whereas other amino acids either correlated poorly or had negative slopes. These data indicate that the protein value of meat and bone meal and poultry by-product meal is limited by the amount of metabolizable methionine they contain.

Research was conducted to develop a more accurate and less time-consuming method of determining expressible moisture in poultry meat. Two modifications of wrapping meat in netting (fold wrap or basket wrap) were compared to a conventional method that did not include wrapping meat. Ground, dark poultry meat, with and without 2.0% added NaCl, was wrapped in netting and analyzed for expressible moisture. The fold wrap method was determined to be more accurate and easier to use, as less expressed meat adhered to the surrounding filter papers. Thus, actual expressed moisture absorbed by filter papers was measured.

A total of 19 government and private industry laboratories in Canada and the United States participated in the collaborative study. Naturally contaminated ground poultry and animal meals, as well as inoculated raw shrimp, were examined for presence of Salmonella by both the modified immunodiffusion method and the Bacteriological Analytical Manual culture method, resulting in an agreement rate of 93.1%. The 2 methods are statistically equivalent for all food types at each inoculation level and for all lots of naturally contaminated foods evaluated in this study. The modification of the AOAC Official Method 989.13, immunodiffusion (1-2 TEST) method for detection of motile Salmonella in all foods, has been adopted revised first action by AOAC INTERNATIONAL.

A rapid, sensitive and selective high-performance liquid chromatographic method is described for simultaneous determination of eight sulfa drugs in meat and meat products using pre-column derivatization with fluorescamine. The drugs are sulfisomidine, sulfadiazine, sulfamerazine, sulfadimidine, sulfamonomethoxine, sulfamethoxazole, sulfadimethoxine and sulfaquinoxaline. The method includes blender extraction of 3-g samples with chloroform, partition with 3 M hydrochloric acid, derivatization with fluorescamine at pH 3.0 and subsequent high-performance liquid chromatographic analysis on a C18 column with fluorescence detection at an excitation wavelength of 405 nm and an emission wavelength of 495 nm. The drugs were separated with a mobile phase of acetonitrile-2% acetic acid (3:5) at 55 degrees C. The average recovery from samples fortified at 0.1 ng/g was 92.6% with a coefficient of variation of 6.2%. The detection limit was 0.01 ng/g for sulfaquinoxaline and 0.005 ng/g for the other seven drugs. The method was field-tested in a survey of 37 samples including beef (five), pork (seven), chicken (seven), ham (five), sausage (eight), bacon (two) and roast beef (three). Sulfadimidine was detected in one pork sample at the level of 0.295 ng/g and in ham at 0.178 ng/g.

The protein nutritional value of meat, poultry, and their products must be considered in relation to humans. Because direct assessment of protein nutritional value in human subjects is impractical for regulatory purposes, methods based on in vitro (chemical) and animal bioassays for assessment of protein quality have been developed. Herein, a case is made for the use of amino acid data as a basis for regulation of meat and poultry products, where considerations of protein nutritional value are included in the regulation. Current data on the protein nutritional quality of these products are based almost entirely on the use of the rat PER assay procedure, supplemented by data on the amino acid content of these products. Because of the inadequacy of the PER assay, the available data base provides an inadequate body of knowledge from which to draw final recommendations concerning policies for regulation of the protein nutritional quality of meat and poultry products. However, if it is necessary to include a measure of protein nutritional quality in a regulation, these data provide a reasonably sound basis for tentatively recommending use of amino acid composition data rather than the standard rat bioassay procedure. In such an approach based on amino acid composition data, consideration might be given to the contents of hydroxyproline (or possibly proline), 3-methylhistidine, lysine, and nitrogen, with a view to establishing a composite or minimum value for the noncollagen muscle protein content of these products.

A Most Probable Number (MPN) method involving Differential Reinforced Clostridial Medium followed by streaking on Willis & Hobbs medium was compared with direct plating of samples on Tryptose-Sulphite-Cycloserine agar without egg yolk, and two forms of Oleandomycin-Polymyxin-Sulphadiazine-Perfringens agar, one being prepared from a commercial, dehydrated product. With skin samples taken from chicken carcasses at different stages of processing, the three direct plating media gave similar counts of Cl. perfringens whereas results obtained with the MPN method were consistently lower. Although counts of Cl. perfringens from various further processed products were usually less than 10/g, the three plating media showed similar specificity for this organism. All media supported good growth of reference strains of Clostridium perfringens but it was found that physiologically similar species, including Cl. absonum, Cl. paraperfringens and Cl. perenne also grew uninhibited in these media and produced colonies identical with those of Cl. perfringens, thus indicating the need for confirmatory tests for Cl. perfringens when examining natural samples.

An extensive survey of the post-1960 literature on the lipids of fowl has been completed. This review shows that the total lipid content of chicken tissues increases with age. The fatty acid composition of both chicken and turkey tissues reflects the fatty acid composition of the dietary fat. The fatty acid composition data for dark meat, light meat, or skin of all classes of chicken --broiler-fryer, roaster, and stewing hen--raised on diets equivalent to commercial feed were combined into single tissue-type fatty acid profiles. Similar profiles were also established for roaster-fryer turkey, young tom turkey, and young hen turkey. Breed, sex, and environmental temperature showed only minor effects on the tissue fatty acid compositions. Young chicken flesh contains less fat than that of stewing hens, turkeys, and other fowl, which all have approximately equal total fat content. White meat of chicken and turkey contains the least amount of fat, and the skin of all birds contained the largest amount, duck and goose skin containing the greatest of all. Tables of the total fat and fatty acid composition of tissue and tissue composites of fowl are given. Studies on chicken and turkey tissues were sufficiently numerous that the computed fatty acid compositions in the tables are considered reliable representation of market birds. Data for goose, duck, partridge, pheasant, pigeon, and quail were computed from sparse information and should be viewedas provisional guides.

In this review, the authors bring together present information on B-vitamin retention in frozen meat as it is affected by: Aging before freezing, the freezing process and length of frozen storage, cooking from the frozen or thawed state, method of thawing, cooking methods, and holding and reheating conditions. Literature reports on various cuts of pork, chicken, beef, lamb, turkey and veal are cited. Thiamin, riboflavin, niacin, vitamin B6, pantothenic acid, vitamin B12, biotin, choline, and folic acid are considered.

The effect of different methods of culinary treatment on the residual amounts of streptomycin and oxytetracycline in the meat and edible viscera (liver, muscle stomach) of egg-layer hens and in the eggs was clarified. Under the effect of heat treatment (cooking, frying, autoclaving) the amount of streptomycin and oxytetracycline in the meat and edible viscera of chicken was found to gradually decrease by comparison with the initial one, with oxytetracycline declining more intensively. In the chicken meat oxytetracycline becomes completely disintegrated after 2 hours of cooking, while amounts of streptomycin in the chicken liver are also much greater than those of oxytetracycline, whereas in the muscle stomach after 2-hour long cooking, in cooked and fried eggs, where oxytetracycline becomes fully disintegrated, certain amounts of streptomycin still continue to be present.

Enzyme-linked immunosorbent assays (ELISA) are described for the detection of poultry and pork in cooked and canned meat foods. These assays are based on species-specific, polyclonal antibodies raised against heat-resistant antigens. The heat-resistant antigens were isolated from raw skeletal muscle tissue of pork and chicken and were found to be immunoreactive even after heating to 120 degrees C for 15 min. The poultry ELISA could detect chicken or turkey at the 126 ppm level, and the pork ELISA could detect pork at the 250 ppm level. Samples of frankfurters, bolognas, pressed meats, canned baby foods, and canned spreads were prepared by simple aqueous extractions.

The present study is a continuation of experiments on adaptation of Pope and Stevens method for rapid determination of proteolytic enzyme activity and protein hydrolysis intensity of food products. The results of the amino nitrogen content of certain meat products are presented by using the earlier described modified method. It was found that when determining amino nitrogen in such raw materials and products as poultry, beef, pork, fresh-water fish and their hydrolyzates, the traditional and colorimetric methods are equal. Good accuracy, specificity and usefulness were qualities noted for the latter method in repeated and routine experimentation.

Effects of product form classifications, consisting of intact turkey drumsticks, dark meat trim tissue, and mechanically deboned meat, on microbiological concentrations were evaluated. Samples were inoculated with actively growing cultures of Salmonella and Clostridium perfringens to increase naturally low bacterial populations prior to being placed at 1 C and 10 C for storage evaluations. Growth support potential for all product forms stored at 10 C was extensive, making it difficult to characterize individual product form effects. Results from samples stored at 1 C indicated that emulsion and trim tissue afforded the greatest growth support potential, probably due to the increased nutrient availability and potential protective effects of the environment associated with the increased surface area of these tissues.

FDA is engaged in a systematic review of approved animal drugs to determine whether upgrading of safety data is required to provide continuing assurance that the approved uses for these drugs are safe. These reviews will be undertaken on the basis of a priority of anticipated human health significance.

A detailed analysis of the amino acid composition data of meat and poultry products, in relation to PER, clearly reveals high correlations between amino acid data expressed in various forms and results of protein quality estimations obtained with the PER assay. The significance of these observations in reference to protein quality evaluation for regulatory purposes will be considered in Background Paper 5.

A collaborative study was conducted to compare automated methods for rapid determination of fat and moisture in meat and poultry products with the official AOAC solvent extraction and forced-air oven methods, respectively. Fourteen products were tested, with fat and moisture contents ranging from 2 to 43% and 44 to 74%, respectively. Eight of the collaborating laboratories analyzed the products by using a moisture/fat analyzer; 4 laboratories used the AOAC methods. Standard deviations for within-laboratory repeatability, between-laboratory reproducibility, and bias for each product indicated that the rapid methods were acceptable. The moisture/fat analyzer methods have been adopted official first action for fat and moisture analyses in meat and poultry products.

The U.S. Department of Agriculture has the responsibility of determining if a method for residues of drugs and pesticides in animal tissues is acceptable for regulatory control, reviewing data on interfering compounds, validating methods, monitoring drug residues in animal and poultry tissues, assigning priority for monitoring drugs and pesticide residues. These responsibilities are carried out in cooperation with the U.S. Food and Drug Administration in the areas of method development, determination of priorities, and punitive action.

A method was developed for measuring low levels of total nitrofurans in animal tissues and milk. The antimicrobial nitrofurans (5 or more products) used in agriculture are extracted from tissue with aqueous acid in the presence of ethyl acetate. After centrifugation and evaporation, the organic residue is washed with hexane and the nitrofurans are hydrolyzed to 5-nitrofuraldehyde in aqueous acid at 70 degrees C. The hydrolysis product is extracted with benzene and measured by gas-liquid chromatography with electron capture detection. Recoveries of nitrofurazone and furazolidone from fortified poultry and swine tissues at the levels of 0.5 and 0.1 ppm are 75 and 65%, respectively. This procedure can be used to detect the total nitrofuran content of as little as 10 ppb muscle tissues and milk, 100 ppb liver, and 50 ppb fat with no interference from related veterinary nitrodrugs.