Microbial profiles of minced meat

Minced meat was examined for microbiological quality and for shelf-life at higher temperatures. Total plate counts, coliforms, Staphylococcus aureus, Enterococci and psychrotrophs were estimated. Types of bacteria associated with meat spoilage were isolated and identified. It was observed that minced meat obtained from local retail shops showed significantly higher microbial counts and shorter shelf-life than that processed under hygienic conditions. The predominant bacteria associated with fresh meat were S. aureus, Micrococcus and Escherichia. The results revealed that microbial spoilage of meat at higher temperatures was mainly due to the growth of mesophilic microorganisms such as Escherichia and S. aureus.     

Quality of meat and meat products produced from southern European pig breeds

Genetic and environmental effects on the quality of meat from southern European pig breeds are discussed. In the literature, it is evident that the breeds native to southern Europe have an interesting quality of products with respect to improved pigs. The free-range system increases the value of animal products due to the influence of outdoor rearing on the chemical, physical and organoleptic characteristics of the product. Traditional food products of high quality, such as those obtained from animals reared outdoor, are in high demand. The studies carried out on native pig breeds in southern Europe have focused on various aspects, ranging from studies of population genetics aimed at averting the danger of extinction and reducing inbreeding to studies of the factors affecting the quality of products. The purpose of this review is to analyse the literature on pig breeds native to southern Europe, with particular reference to the effects of genetics and breeding systems on the quality of products.     

含有谷氨酰胺转胺酶的碎肉粘结剂的研究

为提高低附加值碎肉的利用率,本文以猪肉为原料,利用微生物谷氨酰胺转胺酶(MTG)开发一种碎肉制品粘结剂.MTG与不同浓虔的NaCl组成粘结剂,3%的NaCl与MTG组成的粘结剂重组碎肉效果最好,粘结力达到1.4kg.MTG与不同浓度的酪蛋白、大豆蛋白和小麦蛋白组成粘结剂重组碎肉,添加1%的酪蛋白效果最好,粘结力达到1.5kg.1%的酪蛋白与不同浓度的酶组合作用于碎肉,实验表明,80U/100g肉的酶量效果最佳.本文还探讨了NaCl对酪蛋白/MTG体系粘结效果的影响,低浓度的NaCl会减弱酪蛋白/MTG体系的效果;而3%浓度的NaCl可以提高粘结效果.     

Method for determination of creatine in minced meat

A rather version of picrate method for determination of creatine in minced meat is proposed. It is suitable for application in laboratories of meat-processing plants.     

肉糜加工设备的选型

阐述了骨肉分离技术,简单介绍了几种骨肉分离机的工作原理,对市场上销售的几种主要类型的骨肉分离机加以横向比较,归纳总结了几种类型骨肉分离机的优缺点,为企业选择合适的骨肉分离设备提供参考。     

Salmonella in meat from hunted game: A Central European perspective

The occurrence of Salmonella in meat from game hunted in Europe is reviewed, with a focus on Central Europe. Prevalence in fecal samples is different according to region and game species, ranging from < 5 (wild ruminants) to ca. 20% (wild boar). The pathogen is rarely recovered from carcasses or meat cuts of wild ruminants (< 1%). Prevalences on wild boar carcasses have been reported to range from < 1 to ca. 7%, the tonsils presumably constituting a main reservoir on the eviscerated carcass. On meat cuts from game, recent German and EU (EFSA) reports indicate a prevalence of < 1%. A number of Salmonella enterica serovars can be isolated, with highest prevalences of S. Typhimurium and S. Enteritidis. Persistence of these pathogens in wildlife is a less pressing issue for biology and wildlife conservation than for public health experts, which has been recognized in the framework of zoonoses legislation. On one hand, wildlife is exposed to salmonellae originating from farm animals and humans, and on the other hand, game can be a source of Salmonella in farm animals. Breeding game under intensified conditions (farmed game) as well as extensive breeding of farm animals, notably pigs, can create new epidemiological situations. The pathway of Salmonella from intestinal content of the live animal to individual meat cuts can be described in qualitative terms, yet the relative contribution of the various factors remains to be quantified, which complicates proper risk assessment. Control of Salmonella in the game meat chain is in part based on Good Hygiene Practice from killing and evisceration to chilling and skinning, whereas more detailed data are needed in order to allow risk-based meat inspection.     

Utilization of structurized oilseed proteins in minced meat products

The effect of protein isolate mixtures of sunflower and soya bean seeds on the structural and mechanical properties and the biological value indicer of chopped meat products has been studied. The possibility of using the structurized oilseed proteins in chopped meat products at the rate of 30–50 per cent has been shown.     

Composition of minced meat part A: Methods

A simplified rapid electrophoretic method is described for the identification of venison, pork, and beef in samples of only a few grams of minced meat. The method is based on the species-specific separation patterns obtained upon electrophoresis of the proteins. Venison, beef, and pork can be identified easily and readily from the patterns given by their raw water-extractable proteins.     

Chemical equilibrium of minced turkey meat in organic acid solutions

The distribution of acid (HA), anions (A(-)), free protons (H(3)O(+)) and bound protons (H(b)), in homogenized turkey meat was evaluated at various meat/water mass ratios of (1/4-1/10) during titration with acetic acid (0.25N) or lactic acid (0.2N). H(b) concentration was determined by titration with hydrochloric acid (0.075N) and a correlation for [H(b)]=f(pH) was proposed. A procedure was used to calculate the fractions of the various species in equilibrium, starting from an initial acid concentration in a meat/water system and assuming the accuracy of the pK(a) value of the pure weak acids despite the chemical complexity of meat. Calculated results were in very good agreement (±0.15) with experimental pH values, whatever the acid, meat batch or meat/water mass ratios used. Less than 1% of the total protons were free (H(3)O(+)) and determined the meat pH.     

Composition of minced meat part B: A survey of commercial ground meat

A modified polyacrylamide-gel electrophoretic method was used to differentiate qualitatively various species of meat such as beef, pork, venison, reindeer, and mutton. The composition of commercial minced meat was examined; and illegal adulterations of minced beef with pork were detected.     

Heat transfer during contact cooking of minced meat patties

Experimental results on heat transfer during heating of four types of minced meat patties by contact with hot plates are given. Experimental equipment, method of measurement and experimental values of heat flux from heating plate to heated product surface during 4 min contact cooking are described. Simultaneous measurements of product and heating plate temperatures as a function of time were used to determine the contact heat transfer coefficient between heating plate and product surface. The results show that the heat flux varied during the heating process. The magnitude of the heat flux as a function of time varies with the type of material heated and the heating plate temperature. The heat transfer coefficients measured were in the range 200 to 1200 W m^?2 K^?1, depending on product type, contact plate temperature, contact pressure and stage in the heat treatment.     

Mathematical modelling of mixing of salt in minced meat by bowl-cutter

Salting is one of the basic procedures in food processing. The NaCl concentration influences water holding properties, viscosity, texture, emulsification, etc. It is important to study and model mixing processes by mathematical methods to predict properties of the matrix and the food quality. The objective of this study was to develop a mathematical model of mixing of salt and meat in a bowl cutter and verify this with experimental data. The bowl cutter is described as a continuous stirred tank reactor, combined with a plug flow reactor in a repetitive series-model. The theoretical model shows that 30 rounds are sufficient to get a salt concentration in the whole bulk of meat with a deviation between maximum and minimum values of about 5%. The comparison of the theoretically predicted salt gradient and the experimental results showed that the mathematical equation developed is appropriate to describe the process.     

Microbiological contamination of pig carcasses at different stages of slaughter in two European Union-approved abattoirs

At sequential steps of slaughter (scalding, dehairing, singeing, polishing, trimming, washing, and chilling), 200 pig carcasses from two abattoirs were examined for total viable bacteria count (TVC) and the presence of Enterobacteriaceae and coagulase-positive Staphylococcus (CPS) by the wet-dry double-swab technique at the neck, belly, back, and ham. Before scalding, mean TVCs ranged from 5.0 to 6.0 log CFU cm(-2), and Enterobacteriaceae and CPS were detected on all carcasses. At abattoir A, mean TVCs and the percentage of Enterobacteriaceae-positive carcasses were reduced (P < 0.05) after scalding (1.9 log CFU cm(-2) and 12%, respectively), singeing (1.9 log CFU cm(-2) and 66%, respectively), and blast chilling (2.3 log CFU cm(-2) and 17%, respectively) and increased (P < 0.05) after dehairing (3.4 log CFU cm(-2) and 100%, respectively) and polishing (2.9 log CFU cm(-2)). The proportion of CPS-positive samples decreased to < or = 10% after scalding and remained at this level. At abattoir B, mean TVCs and the percentages of Enterobacteriaceae- and CPS-positive carcasses were reduced (P < 0.05) after scalding (2.4 log CFU cm(-2) and 29 and 20%, respectively), polishing (3.7 log CFU cm(-2)), and chilling (2.6 log CFU cm(-2) and 55 and 77%, respectively) and increased (P < 0.05) after the combined dehairing-singeing (4.7 log CFU cm(-2) and 97 and 100%, respectively). Among sites, the neck tended to yield higher levels of contamination from trimming to chilling at both abattoirs (P < 0.05). Consequently, scalding, singeing, and chilling may be integrated in a hazard analysis critical control point (HACCP) system for pig slaughter. As indicated by the higher levels of contamination on carcasses after dehairing-singeing and the following stages at abattoir B, each abattoir should develop its own baseline data and should customize HACCP systems to match process- and site-specific circumstances.     

转谷氨酰胺酶及非肉蛋白对糜状肉制品质构性能的影响

以猪肉为原料根据中心复合旋转试验设计的原理,采用响应曲面法研究了0,1.5,5,8.5,10 g.kg-1的转谷氨酰胺酶分别与0,5,20,35,40g.kg-1的大豆分离蛋白、酪蛋白、乳清浓缩蛋白、卵清蛋白组成4个试验组,室温催化反应2 h,经85℃30min蒸煮处理后,冷却至4℃,进行质构和蒸煮损失测定.实验结果显示,转谷氨酰胺酶可催化非肉蛋白和肉蛋白质之间的反应,可提高终产品的硬度300～400g,弹性提高0.15～0.3,凝聚性提高0.15～0.2.此外还可以降低产品的蒸煮损失7.5%～10%.而不同的试验组中,酪蛋白处理组对于降低蒸煮损失能力较强,大豆分离蛋白组在改善弹性和凝聚性上作用较强,而卵清蛋白组在提高产品硬度上存在优势.综上表明,向肉制品中添加转谷氨酰胺酶和非肉蛋白是改善肉制品品质的一个有效途径.     

新型肉馅配料及其在肉馅中的应用

介绍了一类以酵母抽提物为原料的新型肉馅配料的生产机理及产品特点,并通过实例阐述了新型肉馅配料在不同肉馅中的应用效果,揭示了提升肉馅类产品风味的一种新趋势.     

素肉与素肉干产品分析

主要对素肉及素肉干的生产原理、产品优势进行了说明;并介绍了即食全素肉干、风味素肉块、素肉粒(酱类制品专用)、风味素肉类制品四种新型素肉类休闲食品.     

Antibiotic and disinfectant susceptibility in Enterobacteriaceae isolated from minced meat.

The resistance of Enterobacteriaceae isolated from minced meat to antibiotics and to an amphoteric surfactant, was examined. Despite the wide range of antibiotic resistance occurring in the strains tested, resistance to the disinfectant was not observed.     

近红外光谱测定不同鲜肉肉糜中蛋白质含量

采集4 000~10 000cm~(-1)波数范围内210份鲜肉(牛、羊、猪肉各70份)为校正集样品光谱数据,在不同的光谱预处理基础上,用偏最小二乘法(partial least squares,PLS)建立了单独的不同种类肉品,及其混合鲜肉肉糜红外光谱与蛋白质测量值之间的定量分析模型。90份鲜肉(牛、羊、猪肉各30份)为预测集样品,采集光谱数据后用于模型的验证。结果表明:鲜肉建模集及预测集相关系数分别为0.954,0.929;RMSEC及RMSEP分别为0.495,0.669。该模型能够很好地实现鲜肉蛋白质含量的快速测定,提高了模型预测的广适性。