The rheological properties of exudates from cured porcine muscle: effects of added non‐meat proteins

Meat exudates were collected from massaged cured porcine M semimembranosus using a model massaging unit. Exudates were used to observe changes in gelation properties due to the incorporation of commercially available non‐meat proteins. These included: soya isolate (90%), sodium (Na) caseinate (85%) and high gelling whey protein concentrates (WPCs, A‐35%, B‐75% and C‐β‐lactoglobulin (55%), as well as a regular 76% protein, WPC D. Compositional analysis ( n=6) showed that incorporation of non‐meat proteins significantly (P<0.05) increased the protein concentration of test exudates in all cases compared to controls. The viscoelastic properties of control and test meat exudate samples (n=6) were analysed using control stress rheology in oscillatory mode. All exudates were heated from 20 to 80°C at 1°C min⁻¹, and subsequently cooled after 30 min back down to 20°C at 1°C min ⁻¹. Addition of WPCs at a 1, 2 and 3% residual powder level and soya isolate at a 1% residual level, resulted in increased storage modulus G′ (Pa) values compared with controls. A 1% residual level of Na caseinate was detrimental to meat exudate gelation, resulting in lower final G′ (Pa) values than those observed for the control. © 1999 Society of Chemical Industry     

Antibiotic Residues in Iranian Honey by Elisa

The aim of this study was to determine antibiotic residues in honey collected from northern part of Iran. The presence of antibiotic residues in honey may be harmful to human health. In this study, the enzyme linked immune assay method was used to investigate of antibiotic residues in honey samples (n = 135) collected randomly from Qazvin Province, Iran. The analyzed antibiotics included enrofloxacin, penicilin, chloramphenicol, gentamicin, tylosin, tetracycline, and sulfonamide. Result show that the range of antibiotic radiuses value was 0.0–72.1 ng/g, besides; the highest percentage of antibiotic residues in honey samples was the enrofloxacin (20.7%). The highest and lowest mean contamination (ng/g) belonged to enrofloxacin (10.8 ± 1.6) followed by Penicillin (4.4 ± 2.9), and chloramphenicol (0.1 ± 0.1). The highest level of antibiotic residues (71.85%) was seen in honey samples collected during the autumn season (P < 0.05).     

Survey of the anticoccidial feed additive nicarbazin (as dinitrocarbanilide residues) in poultry and eggs

A survey was carried out on the occurrence of dinitrocarbanilide (DNC), the marker residue for nicarbazin, in poultry produced in Ireland during 2002–2004. Liver (n?=?736) and breast muscle samples (n?=?342) were tested. DNC residues were found in 40 and 26% of liver and breast muscle samples at levels greater than 12.5 and 5?µg?kg^?1, respectively. DNC residues were found at >200?µg?kg^?1 in 12 and 0% of liver and muscle samples, respectively. Samples of breast muscle (n?=?217) imported from 11 countries were also tested for DNC residues. A lower incidence of DNC residues (6%) was found in imported breast muscle. Egg samples (n?=?546) were tested and DNC residues were found in nine samples, with levels ranging between 14 and 122?µg?kg^?1. Analysis of poultry, carried out as part of official food inspection in the period 2004–2006, indicated a reduction in the number of broiler liver samples containing DNC at >200?µg?kg^?1, to approximately 7%. Low levels of DNC residues continue to be found in <2% of egg samples.     

The applicability of using a protease extracted from cashew fruits (Anacardium occidentale), as possible meat tenderizer: An experimental design approach

Meat tenderness is one of the most important organoleptic properties in determining consumer acceptance in meat product marketability. Therefore, an effective meat tenderization method is sought after by exploring plant-derived proteolytic enzymes as meat tenderizer. In this study, a novel protease from Cashew was identified as a new alternative halal meat tenderizer. The extraction of cashew protease was optimized using response surface methodology (R² = 0.9803) by varying pH, CaCl₂ concentration, mixing time, and mass. pH 6.34, 7.92 mM CaCl₂ concentration, 5.51 min mixing time, and 19.24 g sample mass were the optimal extraction conditions. There was no significant difference (n = 3; p < 0.05) between the calculated (6.302 units/ml) and experimental (6.493 ± 0.229 units/ml) protease activity. The ascending order of the effects was pH < mixing time < CaCl₂ < sample mass. In meat tenderizing application, the meat samples treated with 9% (v/w) crude protease extract obtained the lowest shear force (1.38 ± 0.25 N) to cause deformation on the meat. An electrophoretic analysis showed that protein bands above ~49.8 kDa were completely degraded into protein bands below ~22.4 kDa. Scanning electron microscopy shows the disruption of the muscle fibers after being treated by the Cashew protease. The results of this study show the Cashew (Anacardium occidentale) crude extract can be used as an alternative of the animal and microbial protease as meat tenderizer and subsequently overcome the shortcoming of the halal industrial protease.     

Prevalence and Characterization of Salmonella Isolated from Chicken Meat in Turkey

This study was conducted in a Turkish province to investigate the presence of Salmonella spp. in 150 chicken meat samples using 2 phenotyping techniques: classic culture technique (CCT) and immunomagnetic separation (IMS). For the confirmation of the isolates at molecular levels, invA gene was detected in these isolates. The presence of invA, class 1 (Cls1) integrons, and integrase (Int1) genes was demonstrated by PCR assay; and the resistance of the isolated Salmonella spp. strains to antibiotics was determined by disk diffusion test. All the cultural and PCR results were evaluated together; Salmonella spp. were detected in a total of 64 (42.66%) chicken meat samples. Contamination rate was higher in carcasses (53.33%, n = 75) than in meat pieces (32%, n = 75). When results of standard culture were compared with IMS technique, IMS (n = 54) showed a clear superiority over the CCT (n = 38). A very high resistance rate (≥89.28%) to vancomycin, tetracycline, streptomycin, or nalidixic acid was found. Trimethoprim‐sulfamethoxazole resistance was present in 32.14%. Relatively lower incidence of resistance (≤8.33%) to gentamicin, chloramphenicol, ampicillin, and ceftriaxone was observed. Concurrent resistance to at least 4 antibiotics was detected in 92.85% of the isolates. Cls1 integrons and Int1 were positive in 80.95% and 95.23% of the isolates, respectively. However, Int1 alone was detected in 15.47% (n = 13). In conclusion, the high prevalence of Salmonella spp. in chicken meat may pose a potential public health risk, and the presence of antibiotic‐resistant Salmonella spp. isolate together with Cls1 integron and/or integrase might play an important role in horizontal antibiotic gene transfer.     

The rheological properties of exudates from cured porcine muscle: effects of added polysaccharides and whey protein/polysaccharide blends

Meat exudates collected from massaged cured porcine M semimembranosus were used to observe changes in gelation properties of test exudates containing added polysaccharides, both on their own and in combination with selected whey protein concentrates (WPCs). Three polysaccharide powders, namely sodium alginate, low‐methoxy (LM) pectin and modified potato starch, were assessed at a residual powder level of 2% with Na alginate used at a 0.5% level. Polysaccharides were evaluated both individually and as dry blends with selected WPCs. WPCs assessed included high‐gelling A 35%, B 75% and C 55% protein β‐lactoglobulin powders, as well as a regular 76.5% protein, WPC D. All WPCs were incorporated at a 2% residual powder level in the final meat. Treatment and control meat samples and resulting exudates were prepared in duplicate with analysis performed in triplicate. Viscoelastic properties of control and test meat exudate samples (n = 6) were analysed using control stress rheology in oscillatory mode. Exudates were heated from 20 to 80 °C at 1 °C min⁻¹ with subsequent cooling after 30 min to 20 °C at 1 °C min⁻¹. Combinations of high‐gelling WPCs (especially β‐lactoglobulin) together with modified starch or pectin were found to increase storage modulus G′ (Pa) values compared with control values, with significant (P < 0.05) synergies being observed on dry blending these ingredients. Sodium alginate was found to have a negative effect on G′ (Pa) results, giving lower values compared with control treatments. © 1999 Society of Chemical Industry     

High occurrence rates of enrofloxacin and ciprofloxacin residues in retail poultry meat revealed by an ultra-sensitive mass-spectrometric method,and antimicrobial resistance to fluoroquinolones in Campylobacter spp

An ultra-sensitive mass spectrometric confirmation and quantification method for the determination of selected fluoroquinolones—enrofloxacin and its main metabolite ciprofloxacin—was developed and validated in poultry meat samples. The achieved limits of quantification were 1 ng kg^?1 for enrofloxacin and 10 ng kg^?1 for ciprofloxacin. The analysis of 40 retail poultry samples originating from Estonia, Latvia, Lithuania, Poland and France revealed that 93% of samples contained residues of enrofloxacin in the range from 3.3 to 1126 ng kg^?1. Previous studies have shown high levels of antimicrobial resistance to fluoroquinolones, particularly in Campylobacter spp. and various faecal indicators isolated from broiler meat. Consequently, the revealed widespread usage of fluoroquinolones in the poultry industry may result in the further emergence of antimicrobial resistance of Campylobacter in the food chain.     

Ochratoxin A in traditional dry-cured meat products produced from sub-chronic-exposed pigs

The presence of ochratoxin A (OTA) was determined in traditional dry-cured meat products made from sub-chronically OTA-exposed pigs. The experimental group of pigs (n = 5) was treated with 300 µg OTA kg^–1 of feed during 30 days, whereas the control group (n = 5) remained untreated. After the household production of six types of dry-cured meat products based on traditional recipes, OTA residues were determined in final products produced from each treated and untreated animal using an immunoenzymatic technique (ELISA) and HPLC with fluorescence detection (HPLC-FD). The analytical methods showed acceptable analytical performance results and high correlation coefficients. Mean OTA concentrations ranged from 4.51 ± 0.11 µg kg^–1 in smoked ham to 6.87 ± 2.01 µg kg^–1 in home-made Slavonian sausage. The study demonstrated that pig exposure to OTA leads to the accumulation of OTA residues in muscle and adipose tissue used for the production, and consequently results in contamination of the final meat products.     

The rheological properties of exudates from cured porcine muscle: effects of added carrageenans and whey protein concentrate/carrageenan blends

Meat exudates were collected from massaged cured porcine M semimembranosis using a model massaging unit. Exudates were used to observe changes in gelation properties of test exudates containing carrageenans and whey protein concentrate (WPC) and carrageenan blends. Three carrageenan powders iota (ι ), kappa (κ), as well as a kappa/locust bean gum mix, were assessed at a 1% residual level, both individually and as blends. WPCs assessed included high gelling A‐35, B‐75 and C 55% protein β‐lactoglobulin powders, as well as a regular 76% protein, WPC D. All WPCs were incorporated at a 2% residual powder level in the final meat. Treatment and control meat samples and resulting exudates were prepared in duplicate with analysis performed in triplicate. The viscoelastic properties of control and test meat exudate samples (n=6) were analysed using control stress rheology in oscillatory mode. All exudates were heated from 20 to 80°C at 1°C min⁻¹ , and subsequently cooled after 30 min back down to 20°C at 1°C min⁻¹. Combinations of high gelling WPCs, especially β‐lactoglobulin together with iota and kappa‐carrageenans A and B, were found to increase storage modules G′ (Pa) values when compared with control values. Significant (p<0.05) synergies were observed on blending high gelling WPCs with carrageenans A and B. © 1999 Society of Chemical Industry     

Aflatoxins in composite spices collected from local markets of Karachi,Pakistan

This survey was carried out to evaluate the occurrence of total aflatoxins (AFs; B₁+B₂+G₁+G₂) in unpacked composite spices. A total of 75 samples of composite spices such as biryani, karhai, tikka, nihari and korma masalas were collected from local markets of Karachi, Pakistan, and analysed using HPLC technique. The results indicated that AFs were detected in 77% (n = 58) samples ranging from 0.68 to 25.74 µg kg^?1 with a mean of 4.63 ± 0.95 µg kg^?1. In 88% (n = 66) samples, AFs level was below the maximum limits (ML = 10 µg kg^?1) as imposed by EU. Furthermore, 61% (n = 46) tested samples contained AFs level between 1 and 10 µg kg^?1, 9% (n = 7) exhibited AFs contamination ranged 10?20 µg kg^?1 and only 3% (n = 2) of the investigated samples contained AFs levels higher than the ML of 20 µg kg^?1 for total aflatoxins as set by the USA. It was concluded that there is need to establish a strict and continuous national monitoring plan to improve safety and quality of spices in Pakistan.     

恩诺沙星注射液在猪体内残留消除规律研究

目的研究恩诺沙星注射液在猪体内的残留消除规律。方法本实验采用30头约50 kg重长白猪,随机分为2组,给药组25头,对照组5头。给药组用药量为每次2.5mg恩诺沙星/kg,每日1次,连用3d(1个疗程),使用1个疗程,对照组不给任何抗菌药物,与给药组同环境饲养。在最后一次给药6 h、24 h(1 d)、72 h(3 d)、120 h(5 d)、168 h(7 d)时采集肉、肝、肾、脂肪样本,经液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS)测定组织中的恩诺沙星及其代谢物环丙沙星残留量之和,并利用WT1.4软件计算休药期。结果恩诺沙星注射液在猪肉中的休药期为3.17 d;在肾脏中的休药期为3.75 d;在肝脏中的休药期为8.18 d;在脂肪总的休药期为4.09 d。结论为保证兽药使用安全、食品安全和消费者健康,推荐恩诺沙星注射液在猪体内的休药期为9 d。     

Methicillin‐Resistant Staphylococcus aureus in Raw Meats and Prepared Foods in Public Hospitals in Salvador,Bahia, Brazil

This study investigated the presence of methicillin‐resistant Staphylococcus aureus (MRSA) in raw meat and fish and foods prepared from them for patient consumption in public hospitals in Salvador, Bahia, in northeastern Brazil. A total of 114 samples of raw meat and fish (chicken, n = 30; beef, n = 30; pork, n = 24; and fish, n = 30) and 63 samples of prepared foods (made with chicken, n = 15; beef, n = 15; pork, n = 15; and fish, n = 18) were collected from the kitchens of 10 different hospitals. Of the 114 investigated raw meat and fish samples, 28.1% were positive for MRSA, which comprised 23.3% beef, 23.3% chicken, 37.5% pork, and 30% fish samples. Of the prepared foods, 9.5% were positive for MRSA, which comprised 5.6% chicken products, 6.7% pork products, and 22.2% fish products. MRSA contamination was not detected in prepared beef dishes. A statistical analysis showed no association between the presence of MRSA and the type of raw food (P > 0.05). The high prevalence of MRSA among the raw foods tested and the presence of the microorganism in prepared foods emphasizes the necessity of enforcing hygienic practices within hospital kitchens.     

Toxic and essential metal concentrations in four tissues of red deer ( Cervus elaphus ) from Baranja,Croatia

Kidney (n =?297), liver (n =?52), jawbone (n =?80) and muscle (n =?48) samples collected from red deer (Cervus elaphus) from north-eastern Croatia in the 2002–05 hunting season were analysed for cadmium (Cd), copper (Cu), iron (Fe), mercury (Hg), lead (Pb), selenium (Se) and zinc (Zn) using atomic absorption spectrometry. Statistical evaluation of results showed age-related accumulations of renal cortex Cd and Zn, bone Pb, and muscle Zn. Renal cortex Cd and Zn were significantly associated. In addition, concentrations of Cd and Pb in muscle tissue were significantly correlated with Fe content. Found levels of toxic metals were not likely to affect the health status of animals. A total of 49% of the muscle, 60% of the kidney and 6% of the liver samples were unsuitable for human consumption according to Croatian regulations for Cd in food. However, the calculated intake of Cd through deer meat consumption is small and represents no health risk when consumption is moderate.     

Ultrasensitive Detection of Enrofloxacin in Chicken Muscles by Surface-Enhanced Raman Spectroscopy Using Amino-Modified Glycidyl Methacrylate-Ethylene Dimethacrylate (GMA-EDMA) Powdered Porous Material

Illegally use of enrofloxacin in chicken has raised serious concerns due to its negative effects on public health. In this study, surface-enhanced Raman spectroscopy (SERS) using amino-modified glycidyl methacrylate-ethylene dimethacrylate (GMA-EDMA) powdered porous material was developed and validated to detect enrofloxacin in chicken muscles. By this method, enrofloxacin in chicken muscles was successfully detected at a concentration of 0.01 mg kg^?1, which was lower than the legal maximum residue limit. And the unique “fingerprint-like” spectral patterns of enrofloxacin obtained from SERS spectra could be used for identification and characterization. Compared with high-performance liquid chromatography, the assay of six samples with SERS was rapid in less than 40 min, and the detection was highly sensitive. The results demonstrate that SERS using GMA-EDMA powdered porous material can be potentially employed as a screening tool for rapid detection of residual drugs in a large amount of food samples.     

Natural incidence of zearalenone in Croatian pig feed,urine and meat in 2014

The aim of this study was to determine the levels of zearalenone (ZEN) in different feed materials and feedstuffs for pigs, as well as in pig urine and pig meat following contaminated feed consumption. In total, 253 feed material and feedstuff samples were collected from Croatian pig farms. The results revealed the presence of ZEN in significant concentrations, the maximal being found in maize (5522 µg/kg), wheat (3366 µg/kg) and pig fattening feed (1949 µg/kg). In farms in which high feed contamination and pig hyperestrogenism were observed, samples of pig urine (n = 30) and meat (n = 30) were retrieved as well. The mean ZEN concentrations in pig urine and pig meat were 206 ± 20.6 µg/L and 0.62 ± 0.14 µg/kg, respectively. Despite high contamination of feedstuffs responsible for farmed pigs’ intoxication, ZEN levels determined in pig meat were shown to be of little significance for human safety.     

Prevalence of Salmonellae on Beef Products at Butcheries and their Antibiotic Resistance Profiles

We determined the aerobic plate count at 5 and 25 °C, presence of total coliforms, fecal coliforms, and Escherichia coli, and prevalence of Salmonella species in 354 meat products collected from butcheries. The aerobic counts varied from 3.5 to 10.7 log₁₀ CFU/g. Most of the microorganisms were psychrotrophic. Coliforms were present in all samples except kidneys. Escherichia coli was present at ≥2 log₁₀ CFU/g in ≥50% of the minced meat, liver, and stew. Salmonella species were present in 9.9% of the samples. Minced meat and tripe contained more salmonellae than the other beef. Serogroup E or G (57.1%) was the most predominant serotype. Tetracycline resistance (33.3%) was higher than that of other antibiotics.     

Investigation of enrofloxacin residues in broiler tissues using ELISA and LC-MS/MS

This study investigated the efficiency of an enrofloxacin ELISA test kit to detect the presence of enrofloxacin residues in broiler tissues compared with LC-MS/MS. Broiler tissues from 72 samples consisting of 60 breast muscle, six pools of livers (500 g each) and six pools of kidneys (500 g each) were obtained from six different slaughterhouses. Breast muscle from 10 carcasses and pools of livers and kidneys from approximately 200 carcasses of the same flock were collected from each slaughterhouse. ELISA and HPLC were used to identify and quantify the contamination of the samples with enrofloxacin. A total of 72% of the analysed samples contained enrofloxacin residues detected by the ELISA and 22.2% were detected by LC-MS/MS. The mean values of enrofloxacin contamination found in chicken breast by ELISA and HPLC were 8.63 and 12.25 μg kg^–1, respectively. None of the samples exceeded the maximum limit of 100 μg kg^–1 by both methods set by the European Union as well as the Brazilian Agriculture Ministry. All positive samples for enrofloxacin residues detected by LC-MS/MS were also positive by ELISA. These data confirm the efficiency of the ELISA test, and suggest its use as a screening method for enrofloxacin residues in poultry tissues due to its quick results, low price and ease of applicability.     

The incidence and antibiotic resistance profiles of Salmonella spp. on Irish retail meat products

Irish retail meat (n=74) and poultry samples (n=106) were tested for the presence of naturally occurring Salmonella spp. The pathogen was detected in 28 poultry (n=106), two pork (n=22) and one cooked meat samples (n=20) examined. Salmonella was not isolated from minced beef or lamb samples tested. Initial counts on samples ranged from 0 to log₁₀2·5 cfu g⁻¹. The most commonly isolated serotype was S. bredeney accounting for 48·4%, followed by S. kentucky (35·5%) and S. enteritidis (6·5%). Salmonella spp. (n=31) isolated from food products were also examined for antibiotic resistance. A total of 155 strains (five strains from each isolate) were tested for resistance to 26 antibiotics using the Bauer method. The percentage of samples showing antibiotic resistance amongstSalmonella isolates were as follows: Riampicin (100%); Tetracycline (92·92%); Oxytetracycline (86·26%); Sulphamethoxazole (86·25%) and Streptomycin (80·92%).     

A comparison of enzyme preparations to liberate folic acid for the microbiological assay of feed ingredients

Microbiological assays were conducted to determine the level of total folate in feed ingredients using Lactobacillus casei (ATCC 7469). Fifty-seven samples of feedstuffs were collected from several locations in the southeastern USA by a major broiler producer. Folic acid contents of samples pretreated before assay with three enzymes (conjugase, α-amylase, a mixture of protease (Pronase®, were 22±86 ± 1.99 (μg per 100 g ± SD) for corn (N = 14), 22±01 + 1.18 for fish meal (N = 7), 29.34 ± 0.55 for milo (N = 4), 25.80 ± 6.93 for bakery meal (N = 5), 56.76 ± 4.97 for meat and bone meal (N = 4), 85.14 ± 2.56 for wheat middlings (N = 5), and 193.97 ± 11.19 for soybean meal (N = 18). Predigestion with conjugase, α-amylase and Pronase® liberated folic acid and increased values by 22.3% compared to conjugase predigestion alone (P≤0.05). This study shows that the traditional conjugase pretreatment does not completely free folate from complex feed ingredients for microbiological analysis.     

Assessment of Oxytetracycline Residue in Cooked and Raw Meat of Chicken Broilers Before and After the End of Official Withdrawal Period

The aim of this study was to determine and to compare the presence of oxytetracycline (OTC) residues in raw and cooked (boiled) meat before and after withdrawal period with the Maximum Residue Limits (MRL) using biological and physicochemical techniques. In animal building of 2000 broiler chickens (Gallus domesticus, breed ISA F15) and under the same conditions, 12 healthy adult chickens were selected and divided in two groups (n?=?6 in each group). The sample was treated by Oxytetracycline® 20% (0.4 g/kg) during 3 days. Juices and muscles tissues were sampled twice for this assay: first, the broiler chickens were slaughtered (n?=?6) 24 h after the third day of treatment. However, the second sampling (n =?6) was performed 24 h after the end of the withdrawal period. For each portions of sample, the juice meat and muscle tissues samples were collected after cooking at 80 °C during 45 min and after freezing/defrosting for the raw meat. Biological methods consisted of using four plates test (FPT) to pre-screening and Premi®Test to screening. Finally, to confirm and to quantify the accurate level of OTC in positive samples, ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) measurements were conducted. The FPT test showed that all samples were positive. While the Premi®Test analysis showed negative results for raw meat tested and positive results for juice of meat cooked in both samples. The obtained results using UHPLC-MS/MS methods confirmed the previously results. Thus, the presence of such toxic substances in our diet constitutes a major health risk for consumers, requiring the establishment of an adequate monitoring system. There is a paucity of official withdrawal periods for veterinary medicinal products in cooking meat; a relationship between the concentrations of residues of antibiotics after waiting period and cooking is not established since meat is always cooked before consumption.