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.     

2018—2019年洛阳市市售熟肉制品中亚硝酸盐含量分析

目的 了解2018—2019年洛阳市市售熟肉制品亚硝酸盐含量情况.方法 随机采集洛阳市市售熟肉制品222份,按照GB 5009.33—2016《食品安全国家标准食品中亚硝酸盐与硝酸盐的测定》第二法分光光度法对其进行亚硝酸盐含量进行测定,依照GB 2760—2014《食品安全国家标准食品添加剂使用标准》进行判定.结果 2...     

Irradiation is useful for manufacturing ready-to-eat cooked meat products enriched with folic acid

Cooked sausages enriched with folic acid (0.6, 1.2 and 2.4 mg/100 g) were manufactured as ready-to-eat (RTE) products using E-beam radiation (2-4 kGy) as a non-thermal technology. The effects of this treatment on the folic acid content, colour, texture and sensory properties of the final products were studied. The characteristics of sausages were not affected by the presence of folic acid, independently of the amount added, and their overall acceptability was good. Doses of 4 kGy caused losses of folic acid close to 20-30% and significantly decreased the sensory quality (P<0.05). Despite this, the final content of folic acid in all products was sufficient so that 50 g of product gave 100% of the recommended daily allowance (RDA). This new RTE meat product can be considered as a source of folic acid that can help assure adequate levels of this vitamin in the general population.     

Assessment of possible human exposure to ochratoxin A in Croatia due to the consumption of dry-cured and fermented meat products

Ochratoxin A (OTA) is a toxic secondary metabolite produced by the fungi of Aspergillus and Penicillium species. Data indicate a frequent OTA contamination of cereals and cereal products, and consequently also the contamination of meat and meat products. The aim of this study was to determine a possible level of meat product consumers’ exposure to OTA through the consumption of dry-cured and fermented meat products available on the Croatian market. Data showed the weekly OTA intake of 90% of male dry-cured ham consumers to be a maximum of 51.9 ng kg^–1 b.w., i.e., far below the tolerable weekly intake (TWI) of 120 ng kg^–1 b.w. weekly set out by the European Food Safety Authority (EFSA). OTA intake coming from the consumption of other meat products under study is lower and ranges from 0.1 to 42.1 ng kg^–1 b.w. weekly, dependent on the study. The study demonstrated that meat products in Croatia do not constitute a notable source of OTA in the human diet, so that the human health risk coming from the consumption of dry-cured and fermented meat products is negligible.     

Cholesterol oxidation products in irradiated raw meat with different packaging and storage time

The effect of irradiation and packaging conditions on the formation of cholesterol oxidation products (COPs) as well as lipid oxidation products was determined in raw turkey leg, beef, and pork loin meat during 7 days of storage. Ground turkey leg, beef, and pork loin muscles were prepared as patties. The patties were individually packaged either in oxygen-permeable or impermeable bags, irradiated at 0 or 4.5 kGy using a Linear Accelerator, and stored at 4°C. The COPs such as 7-hydroxycholesterol, 7β-hydroxycholesterol, and 7-ketocholesterol were detected in fresh raw meats at 0 day at the level of 10.9 to 49.2 μg/g lipid. After 7 days of storage, other COPs such as epoxides, 20-hyroxycholesterol, and choletanetriol were formed in mainly aerobically packaged and irradiated raw meats. Packaging effect was more crucial on the cholesterol and lipid oxidation than irradiation. In aerobically packaged and irradiated meats, turkey leg muscles had higher COPs value than beef or pork did. COPs and thiobarbituric acid reactive substances (TBARS) values had a strongly positive correlation in turkey leg and pork. But, cholesterol oxidation in beef proceeded in irradiated and aerobically stored samples despite of its low level of TBARS value.     

北京市S区居民熟肉制品中亚硝酸盐膳食暴露风险评估

目的 了解北京市S区居民通过熟肉制品暴露亚硝酸盐的潜在健康风险及影响因素。方法 采用分光光度法对S区2013—2019年市售535份熟肉制品中的亚硝酸盐含量进行监测,结合S区不同年龄组居民肉制品的个体消费量数据,并与联合国粮农组织/世界卫生组织的食品添加剂联合专家委员会（FAO/WHO JECFA）规定的亚硝酸盐每日允许摄入量（ADI）0.07 mg/kg·BW进行比较,评价其膳食暴露健康风险。结果 北京市S区市售熟肉制品中亚硝酸盐的检出率为94.02%,总体超标率为9.16%。2岁以上人群通过熟肉制品的亚硝酸盐每日暴露量范围为0.000 0~0.390 0 mg/kg·BW,平均暴露量为0.018 8 mg/kg·BW,其中有2.5%人群的暴露量超过了ADI。除50~64岁组和≥80岁组外,其他年龄组人群熟肉制品来源亚硝酸盐日暴露量均超过了ADI。2~5岁组和6~12岁组熟肉制品来源亚硝酸盐日暴露量在P₉₅百分位上超过了ADI,处在不可接受水平;13~17岁组熟肉制品来源亚硝酸盐日暴露量在P₉₅百分位上等于ADI。结论 S区市售熟肉制品中亚硝酸盐残留有导致部分人群存在慢性毒害的风险,应加强监管和抽检力度,向公众普及亚硝酸盐相关知识,最大限度地减少外源性亚硝酸盐的添加和内源性亚硝酸盐的产生。     

Reduction of ochratoxin A in dry-cured meat products using gamma-irradiation

This study investigated the efficiency of gamma (γ)-irradiation in the reduction of ochratoxin A (OTA) present in dry-cured meat products prepared from intentionally contaminated raw materials from OTA-treated pigs. OTA concentrations determined in the samples (n = 24) ranged from 25.8 μg kg^–1 in bacon to 17.8 μg kg^–1 in smoked ham. After γ-irradiation at doses of 3, 7 and 10 kGy (i.e. the doses used in the food industry), a dose-depended OTA reduction was observed; however, it was not statistically significant. The mean OTA reduction achieved with 3-, 7- and 10-kGy γ-doses was approximated to 8.5%, 13.9% and 22.5%, respectively. The storage of irradiated samples (1 month, 4°C) did not significantly affect OTA levels. Based on the correlation between the OTA reduction level and basic chemical composition of dry-cured meat samples, OTA reduction may be linked to the samples’ fat content. The results indicate that γ-irradiation can reduce OTA levels in dry-cured meat products, but only to a limited extent due to the complexity of the matrix.     

An innovative method of immersion vacuum cooling for cooked meat products: immersion vacuum cooling with ultrasonic assistance

In this paper, immersion vacuum cooling with ultrasonic assistance (IVCUA) is compared with immersion vacuum cooling alone (IVC) and vacuum cooling (VC) for cooling time, mass loss, colour, texture profile and water mobility and compartmentalization for cooked meat products. The results reveal that IVCUA clearly enhances the boiling intensity of impregnation liquid compared to IVC. The total cooling time using IVC (126.56 min) for samples from 72 to 4 °C was significantly longer (P < 0.05) than that of IVCUA (96.89 min) and VC (80.48 min). The cooling time of samples from 10 to 4 °C by IVC (46.26 min) was higher (P < 0.05) than that by IVCUA (28.55 min). There were no significant differences (P > 0.05) in mass loss, colour and texture profile among all samples. However, IVCUA had a higher transverse relation time of bulk water (T₂₄) and MRI proton densities (P < 0.05), as well as a more uniform water distribution compared to IVC.     

Evaluation of protein aggregation in cooked meat

The effect of meat cooking on protein aggregation was measured in pig M.Longissimus dorsi. Muscles were aged 4 days in air and then cooked at 100 °C for 10 or 30 min. Meat was ground in a KCl solution and the whole extract was delipidated with a mixture of butanol and di-isopropyl ether in a 40:60 v/v ratio. Protein aggregation induced by cooking was evaluated with a laser granulometer, which enabled reliable and reproducible characterisation of particle size distributions, and particle shape distributions using automated imaging techniques. Cooking significantly decreased the level of big particles, while the number of small particles remained stable. Cooking also affected the form and size of the particles. In order to better understand the mechanisms implicated in the aggregation process the level of protein oxidation and the protein surface hydrophobicity were evaluated in parallel with the granulometry measurements. Significant correlations were observed between the granulometry parameters and some of the protein oxidation indices. The protein surface hydrophobicity was also correlated with the granulometry parameters demonstrating the impact of thermal denaturation on the aggregation process.     

影响熟肉制品辐照所致脂肪氧化因素分析

就辐照诱导熟肉制品脂肪氧化机理进行了阐述,并分析不同因素(如脂肪含量、辐照剂量、包装形式、贮藏温度、添加剂、贮藏时间等)对辐照熟肉制品脂肪氧化的影响。     

Utilisation of protein fractions from porcine spleen as technofunctional ingredients in emulsified cooked meat sausages

Spleen is a low commercial value meat by-product from industrial slaughterhouses that is mostly underutilised. In this study, porcine spleens were processed to obtain two protein fractions (i.e. soluble and insoluble extracts in sodium citrate buffer 0.1 m pH 5) and the potential of using them to replace functional ingredients in cooked sausages was assessed. Specifically, a pasteurised insoluble protein extract was used as soy protein replacer in mortadella-type sausages, whereas spray-dried soluble proteins were used instead of sodium caseinate in Frankfurt-type sausages. Both splenic extracts performed well as functional ingredients since no differences in proximate composition, emulsion stability, water-holding capacity or texture were found. The only differences were found in the colour of the sausages containing the soluble protein extract, because of the haem and myoglobin content in this ingredient. The results showed that spleens could be a suitable source of non-allergenic functional proteins for meat products.     

Occurrence of ochratoxin A in raw ham muscle,salami and dry-cured ham from pigs fed with contaminated diet

Pork meat-derived products can contribute to the overall ochratoxin A intake, either by carry-over effect, or by environmental mould population cross-contamination. In order to assess the role of these different contamination routes, a study was carried out with pigs challenged orally with OTA contaminated feed at subchronical level. After slaughtering, thighs and minced meat from control and treated groups were transformed into dry-cured hams and salami, respectively, which were analysed for OTA determination after ripening. From collected data, the carry-over in muscle was generally low, whereas a significant contribution to the OTA contamination in dry-cured hams was due to toxinogenic mould population growing on their surface during ripening. Finally, a survey of different types of dry-cured ham (n = 110), from the Italian market, was performed, showing the occurrence of OTA on the surface portion in 84 out of 110 samples with a median value of 0.53 μg/kg and in the inner core in 32 out of 110 samples with a median value lower than 0.1 μg/kg.     

散装熟肉制品中单增李斯特菌污染状况分析

目的分析散装熟肉制品中单增李斯特菌污染状况。方法根据GB 4789.30-2016《单核细胞增生李斯特氏菌检验》规定的方法对散装熟肉制品的加工用原料、生产环境、各加工环节中产品以及不同销售环境下产品中的单增李斯特菌进行定性和定量检测。结果原料肉的总体带菌率达到21%;生产环境中第三区(远离食品接触面的区域)检出率为2%,其余区域未检出;各加工环节中产品单增李斯特菌检测结果均小于10CFU/g;不同销售环境下产品中单增李斯特菌检测结果小于10 CFU/g的比例为93%,处于10～50 CFU/g之间的样本占比6%,大于50 CFU/g的占比为1%。结论原料散装熟肉制品中单增李斯特菌污染的主要来源,蒸煮等加工环节能有效地杀灭单增李斯特菌。销售环境也关系到散装熟肉制品单增李斯特菌的污染程度,对于未包装的产品,专卖店优于农产品市场。     

熟肉制品中亚硝酸盐含量调查

目的了解河南省熟肉制品中亚硝酸盐的含量。方法 2010年从全省18个地市随机采集了14类361份熟肉样品,用国标法GB/T 5009.33—2010分析熟肉制品中亚硝酸盐的含量。结果熟肉制品中亚硝酸盐的平均含量为54.46 mg/kg;依据GB 2760—2011《食品添加剂使用标准》判定,亚硝酸盐超标的熟肉制品为92份,总超标率为25.5%,其中牛肉制品中的亚硝酸盐超标率最高为42.0%,其后依次为猪肉制品27.8%、鸡肉制品10.2%、羊肉制品9.5%。结论提示河南省熟肉制品中亚硝酸盐含量超标情况比较严重,政府有关部门应加强对食品安全的监督管理,以维护广大消费者的身体健康。     

东莞市区肉菜市场熟肉制品中金黄色葡萄球菌污染溯源分析

目的优化熟肉制品中金黄色葡萄球菌的快速污染溯源分析方法。方法对熟肉制品及其加工环境进行采样,应用3MPerifilmTM金黄色葡萄球菌快速测试片对样品定量检测,对分离出的阳性菌株运用全自动微生物基因指纹鉴定系统RiboPrinter,结合EcoRI酶,对其进行分子溯源。结果 168个样品中分离出的7株菌共分为2种核糖体基因型,其中6株为同一核糖体条带类型,显示来源于相同克隆株。结论该方法全程只需3 d时间,快速稳定,可满足监管快速检测鉴定、分型溯源的要求。RiboPrinter的优势在于快速溯源,进行种的鉴定时应结合其他手段来进行确认。     

2022年上海市生禽肉和调理肉制品中主要食源性致病菌监测

目的 分析上海市市售生禽肉和调理肉制品中沙门菌、单核细胞增生李斯特菌及小肠结肠炎耶尔森氏菌等食源性致病菌的污染情况。方法 2022年1～8月,从上海市农贸市场、超市、餐饮店等环节采集样品348份,其中生禽肉240份,调理肉制品108份。按照食品安全国家标准分别对样品中的沙门菌、单核细胞增生李斯特菌和小肠结肠炎耶尔森氏菌的检测。采用VITEK2全自动微生物鉴定仪对可疑菌株进行生化鉴定,并对沙门菌分离株进行血清学分型。结果 生禽肉中沙门菌、单核细胞增生李斯特菌和小肠结肠炎耶尔森氏菌的检出率分别为28.33%(68/240)、5.00%(12/240)和0.83%(2/240);调理肉制品中沙门菌、单核细胞增生李斯特菌和小肠结肠炎耶尔森氏菌的检出率分别为5.56%(6/108)、28.70%(31/108)和1.85%(2/108);血清学分型结果显示,生禽肉中68株沙门菌分布于14种不同血清型,其中科瓦利斯沙门菌（35.29%）、鼠伤寒沙门菌（16.18%）和肠炎沙门菌（13.24%）占比较高,调理肉制品中6株沙门菌分布于3种不同血清型,分别为肠炎沙门菌（66.67%）、肯塔基沙门菌（16...     

DNA tests based on coat colour genes for authentication of the raw material of meat products from Iberian pigs

Traceability in the meat supply chain depends on systems based on electronic identification, but DNA tests would be suitable to audit the genetic origin of some labelled meat products. Differentiated labelling is required for highly prized meat products from purebred Iberian pigs and from animals crossbred with the Duroc breed. A panel of breed specific markers based on polymorphisms found in two coat colour genes was investigated in the present study. The genotyping of the G/C or A/G polymorphisms at nucleotide positions ?160 and 727 bp of the melanocortin receptor 1 (MC1R) gene can be indistinctly used to discriminate the Duroc specific allele (MC1R*4) from all the alleles (MC1R*3, MC1R*6 and MC1R*7) found in the Iberian breed. It allows one to differentiate unambiguously samples from purebred Iberian and Duroc crossbred genotypes. The additional genotyping of the A/G polymorphism at position 2462 of the pink‐eyed dilution (OCA2) gene, four microsatellites (SW24, SW413, SW874 and SW1057) and nine amplified fragment length polymorphism (AFLP) markers would allow one to detect Duroc crossbred genotypes with a probability of exclusion of the pure Iberian origin greater than 0.968. The validation of batches of marketed products may be achieved with more single tests on pooled DNA samples. Copyright © 2004 Society of Chemical Industry     

The determination of soya and meat protein in raw and processed meat products by specific peptide analysis. An evaluation

The detection and measurement of characteristic peptides formed on enzymatic hydrolysis of soya protein products, meats and offals is described. Samples were heated at 120°C for 3h prior to digestion with trypsin overnight, and the resultant peptide mixtures passed through an Amicon ultrafiltration membrane. After concentration the ultrafiltrates were analysed by ion exchange chromatography on Aminex A5 resin. Peptides were detected by post-column reaction with ninhydrin. Characteristic peaks designated SP 2 and MP 1 were seen in chromatograms of digests of soya protein isolate and beef respectively, and these peaks were well resolved in beef and soya protein isolate mixtures. The SP 2 peak was shown to contain peptides derived from soya 11 S globulin. The soya protein and beef contents of a series of mixtures of freeze-dried, defatted beef and soya protein isolate were determined by measurement of the SP 2 and MP 1 peaks respectively. Soya protein content could be determined within 2% of the true value over the range 30–70% soya protein isolate and beef content could be determined within 5% of the true value in the range 20–100% beef. Analysis of five soya protein isolates, four soya protein concentrates, six soya flours and 13 textured soya products indicated considerable interproduct variation in the yield of SP 2. The MP 1 peak was seen in a range of meats, both cooked and raw. It was also present in digests of offals which contained smooth or striated muscle but not in ‘non-muscle’ offals. The protein origin of the MP 1 peak was not established but the yield appeared lower in meat products which had been heated during manufacture than in those which had received no such treatment. Analysis of a series of laboratory prepared canned and heated pork and soya protein isolate mixtures enabled the pork content to be determined to within 8% of the true value, 2% soya protein isolate could be detected but not quantified accurately.     

Diversity of lactic acid bacteria from modified atmosphere packaged sliced cooked meat products at sell-by date assessed by PCR-denaturing gradient gel electrophoresis

The predominant lactic acid bacteria (LAB) microbiota associated with three types of modified atmosphere packaged (MAP) sliced cooked meat products (i.e. ham, turkey and chicken) was analyzed at sell-by date using a combination of culturing and molecular population fingerprinting. Likewise routine analyses during industrial MAP production, meat samples were plated on the general heterotrophic Plate Count Agar (PCA) and on the LAB-specific de Man, Rogosa, Sharpe (MRS) agar under different temperature and atmosphere conditions. Subsequently, community DNA extracts were prepared from culturable bacterial fractions harvested from both media and used for PCR targeting the V3 hyper-variable region of the 16S rRNA gene followed by denaturing gradient gel electrophoresis (DGGE) of PCR amplicons (PCR-DGGE). Irrespective of aerobic or anaerobic incubation conditions, V3-16S rDNA DGGE fingerprints of culturable fractions from PCA and MRS medium displayed a high level of similarity indicating that LAB constituted the most dominant group in the culturable bacterial community. Comparison of DGGE profiles of fractions grown at 20, 28 or 37 °C indicated that part of the culturable community consisted of psychrotrophs. Four DGGE bands were common among cooked ham, turkey and chicken products, suggesting that these represent the microbiota circulating in the plant where all three MAP product types were sliced and packaged. Based on band sequencing and band position analysis using LAB reference strains, these four bands could be assigned to Lactobacillus sakei and/or the closely related Lactobacillus fuchuensis, Lactobacillus curvatus, Carnobacterium divergens and Leuconostoc carnosum. In conclusion, the PCR-DGGE approach described in this study allows to discriminate, identify and monitor core and occasional LAB microbiota of MAP sliced cooked meat products and provides valuable complementary information to the current plating procedures routinely used in industrial plants.     

Control of food spoiling bacteria in cooked meat products with nisin,lacticin 3147, and a lacticin 3147-producing starter culture

Nisin, in the form of the commercial product Nisaplin, and lacticin 3147 in whey powdered form were added to minced pork-meat in amounts of 0.15% (w/w) and 1.5% (w/w), respectively. The meat was cooked and inoculated with a Staphylococcus aureus strain of meat origin and a Listeria innocua strain at a level of 10⁷ or 10⁵ CFU g^–1. The batches were stored vacuum-packaged for 21 days at 8 °C. Nisin and lacticin 3147 immediately reduced the L. innocua population at the time of inoculation. Nisin showed higher inhibitory activity than lacticin 3147. During the storage period, a slight L. innocua growth was observed in the batches inoculated with the larger inoculum, and a bacteriostatic effect was observed against Listeria in the batches inoculated with 10⁵ CFU g^–1. Nisin maintained a constant S. aureus population in the cooked batch inoculated with 10⁷ CFU g^–1, although the bacteriocin was capable of reducing the amount of S. aureus by 90% in the batch inoculated with 10⁵ CFU g^–1. On the other hand, lacticin 3147 did not show an inhibitory effect against S. aureus in the cooked meat. The starter culture Lactococcus lactis DPC 303-T4 (containing the conjugative plasmid encoding production of lacticin 3147) was inoculated in a portion of a Longissimus dorsi pork muscle with brine. L. lactis DPC 303-T4 performed a good fermentation, but lacticin 3147 production was not found after 7 days at 12 °C of storage.