机械去骨禽肉糜的应用及研究进展

介绍国内外机械去骨禽肉糜(MDPM)在食品中的应用及其在应用中出现的问题,如乳化、脂肪氧化、血红素氧化等,并探讨其开发利用前景.     

提高肉制品保水性方法的研究进展

肉制品的保水性是衡量肉制品品质和经济价值的重要指标之一,如何提高肉制品的保水性具有重要意义。本文对影响肉制品保水性的因素和提高肉制品保水性的方法进行了综述,希望为肉制品的生产加工提供参考。      

Biological evaluation of mechanically deboned chicken meat protein quality

Mechanically deboned chicken meat (MDCM) is a meat product obtained by crushing tissues after meat removal and is largely used in meat products. Protein quality of flour prepared from defatted MDCM and from fresh chicken breast meat (FCBM) was chemically and biologically evaluated by rat growth and nitrogen balance studies. Proximate chemical composition, on a dry basis, of MDCM and FCBM showed protein contents of 90.5% and 82.2%, lipid contents of 3.0% and 13.2% and ash contents of 6.1% and 4.2%, respectively. There was a relatively good balance of essential amino acids in both samples although lysine was in low concentration in MDCM being a limiting amino acid. Feeding of flour diets resulted in high protein efficiency ratio, a high net protein utilization and high nitrogen balance, thus showing a high biological value and also high true digestibility and, consistently, NPU for both samples is similar to casein.     

Effect of gamma radiation on refrigerated mechanically deboned chicken meat quality

Samples of mechanically deboned chicken meat (MDCM) were irradiated in the frozen form with doses of 0.0, 3.0 and 4.0 kGy, stored at 2±1?°C and evaluated for their sensory characteristics, color, thiobarbituric acid reactive substances (TBARS) and total psychrotrophic bacterial count for up to 12 days. The sensory analysis showed that volatile compounds associated with the odor irradiation produces, were dissipated from the samples of irradiated MDCM during storage and that the oxidation odor perceived in the samples irradiated with doses of 3.0 and 4.0 kGy was more pronounced (P<0.05) than in the non-irradiated samples, as from the 8th and 12th day of refrigeration, respectively, in agreement with the TBARS values. Irradiated MDCM showed higher values (P<0.05) for a(?) (redness) than the non-irradiated samples as from the 4th day under refrigeration. Considering the sensory analyses, color, psychrotrophic bacterial counts and TBARS analyses as a whole, the MDCM samples irradiated with doses of 0.0, 3.0 and 4.0 kGy were acceptable under refrigerated storage for 4, 10 and 6 days, respectively.     

The quality evaluation of frankfurter-type sausages from hand and mechanically deboned turkey meat

A quality evaluation was made of frankfurter-type sausages made from hand and mechanically deboned meat from various parts of turkey carcasses. The results led to the conclusions that despite some differences in objective measurements of the sausage quality, mechanically deboned turkey meat can be considered as an exclusive meat raw material for the production of frankfurter-type sausages. The quality of sausages from mechanically deboned turkey meat from wings and frames with skin was the least satisfactory.     

The quality evaluation of frankfurter-type sausages from hand and mechanically deboned turkey meat

Zusammenfassung Im Rahmen dieser Untersuchungen wurde die Qualitätsbewertung von Brühwürsten aus verschiedenem hand- oder mechanisch entbeintem Putenfleisch durchgeführt. Es wurde festgestellt, daß das mechanisch entbeinte Putenfleisch ein ausgezeichneter Rohstoff für die Brühwurstherstellung ist, obwohl zwischen beiden (hand- oder mechanisch) Fleischarten Unterschiede bestehen. Die minderwertigste Qualität zeigten Brühwürste, die aus mechanisch entbeinten Putenschwingen oder Putenknochen mit Haut hergestellt wurden.

---

The quality evaluation of frankfurter-type sausages from hand and mechanically deboned turkey meat

Summary A quality evaluation was made of frankfurter-type sausages made from hand and mechanically deboned meat from various parts of turkey carcasses. The results led to the conclusions that despite some differences in objective measurements of the sausage quality, mechanically deboned turkey meat can be considered as an exclusive meat raw material for the production of frankfurter-type sausages. The quality of sausages from mechanically deboned turkey meat from wings and frames with skin was the least satisfacory.

     

Quality of comminuted sausages formulated from mechanically deboned poultry meat

Comminuted sausages formulated with mechanically deboned poultry meat-MDPM (turkey or chicken, frame or neck) treated in different ways before production (vacuum packed MDPM or air packed skeletons deboned at production) and stored frozen for 6 or 18 weeks have been studied using a full-factorial design and chemical, physical and sensory analysis. MDPM was obtained from a Beehive separator. Comminuted sausages with MDPM from turkey frames, stored at -25?°C as skeletons, packed in air for 18 weeks developed marked rancid odour and flavour which could also be detected by thiobarbituric acid reactive substances (TBARS) and the concentration of volatile compounds. Vacuum packed mechanically deboned meat irrespective of species and carcass part could be stored for up to 18 weeks and used in formulation of sausages without any serious changes in their sensory profiles. Instrumental colour differences between sausages were mainly due to species. Turkey sausages were darker, redder and less yellow than chicken sausages. Moisture and fat contents were influenced by carcass part and to a lesser extent depended on species and storage time. Principal least squares regression (PLS2) showed close relationships between instrumental parameters and sensory attributes. TBARS, hexanal and volatile compounds were highly correlated with rancid flavour while redness (a(?)) was strongly related to sensory colour hue and colour strength.     

The effects of high salt and low pH on the water-holding of meat

The study investigated the water-holding (WH) in meat in the pH–NaCl (ionic strength) combinations that prevail in dry sausages during fermentation and drying. WH in raw beef homogenates, with 230% added water, was determined by centrifugation at pH values of 5.47–4.60, and ionic strengths (μ) 0.50–1.50. The minimum WH in relation to pH was at pH 4.8, but at higher pH values, the WH optimum was at 1.0–1.5 μ; at lower pH-values (< 5.0) the optimum was more pronounced at 1.0 μ. The WH reducing effect by pH decrease was stronger than the effect of μ. At lower pH values, the relative effect of μ on WH was higher compared to that of pH than at higher pH values. The pH–salt combinations prevailing in fermented sausage in the beginning of the ripening produced a high WH, which decreased, first with pH decrease and then in the last period of ripening mainly due to the increase of ionic strength.     

Fate of unirradiated Salmonella in irradiated mechanically deboned chicken meat.

Mechanically deboned chicken meat was irradiated at 0, 1.25 and 2.50 kGy (Cesium 137) and inoculated with Salmonella dublin ATCC 15480, Salmonella enteritidis ATCC 9186 or Salmonella typhimurium ATCC 14028. Samples were then stored at 5 degrees C and 10 degrees C and were subjected to microbiological analysis directly after irradiation and inoculation (time 0), and after 24, 72, 120, 168 and 216 h of storage. Samples stored at 20 degrees C were examined at time 0 and after 6, 12 and 24 h of storage. Irradiation at 1.25 and 2.50 kGy caused an average reduction in bacterial levels of 2.23 and 3.44 logs, respectively. S. dublin, S. enteritidis and S. typhimurium showed very small, insignificant changes in numbers, during storage of meat for 9 days at 5 degrees C. The final populations of S. dublin and S. typhimurium in samples irradiated before inoculation and stored at 10 degrees C or 20 degrees C were greater than the equivalent populations in samples which had not been irradiated before inoculation. Reduction of indigenous microflora in mechanically deboned chicken meat by irradiation may create better conditions for the growth of salmonellae and may thus increase the risk of salmonellosis when accidental contamination and temperature abuse occur after a radiation treatment. Therefore, irradiated mechanically deboned chicken meat should be properly refrigerated and protected against contamination.     

Effects of aqueous washings on colour and nutrient quality of mechanically deboned chicken meat

Mechanically deboned chicken meat (MDCM) was washed with water, 0·5% NaCl or 0·5% NaHCO(3) solutions. Approximately 75·5% of the total hemoprotein pigments were removed by washing of MDCM with a sodium bicarbonate solution which resulted in the best colour improvements in the samples. Approximately 18·7% of total lipids were removed as a result of aqueous washing. The yield of proteins ranged from 56·5% after one washing with water to 43·4% after washing with water and then with a sodium bicarbonate solution. The Hunter L and a colour parameters of the samples correlated well with the total hemoproteins (correlation coefficients -0·984 and +0·947, respectively); corresponding correlation coefficient with the Hunter b value was only +0·693.     

生鲜猪持水性的核磁共振研究

用低场核磁共振仪检测了宰后猪肉样品水分分布的变化情况.研究发现:肉中有三个明显的水分群,分别时应的横向弛豫时间是T21、T22、T23,其中T23积分面积与滴水损失之间的相关系数为-0.860.实验数据表明,LF-NMR的横向弛豫时间是研究持水性和水分分布的一种非常有效的方法.     

Effects of protein oxidation on the texture and water-holding of meat: a review

Abstract

Protein oxidation readily occurs in postmortem muscle during storage and processing. Over the past decade new analytical methods have been developed and new aspects of protein oxidation in meat have been studied, such as the reaction mechanism, and impacts on eating quality and nutritional value. It is now evident that amino acid side chains in myofibrillar proteins undergoes modifications due to oxidative stress. In turn this will lead to formation of new protein-protein cross-links in structural proteins, however, also the overall level of fixed-charge groups attached to the peptide backbones is modified. Meat texture and water-holding are important quality attributes and they are affected by the oxidation of structural proteins. Different mechanisms have been suggested to explain the oxidation-induced quality changes, focusing mainly on reduced proteolysis and formation of cross-links. This review explores the current understanding of protein oxidation in fresh meat in relation to texture and water-holding. The consequences of protein oxidation at molecular level in relation to oxidation-induced cross-linking and changes in net charges of myofibrillar proteins, and the impacts on texture and water-holding are discussed.     

Muscle pH(60), colour (L, a, b) and water-holding capacity and the influence of post-mortem meat temperature

The use of the pH(60) and colour parameters (L, a, b) as chilled pork drip loss predictors 24 h post-mortem as well as the influence on this meat characteristic of an early blast cooling regime (90 min post-mortem) were investigated. Despite the best correlation found with pH(60) (-0·647), both indicators were found to be poor for this purpose, it being impossible to use them alone for pork quality classification (PSE/DFD status). Comparing the evolution between the drip losses on chilled and early deep frozen (-60°C) longissimus dorsi pork cuts, the results indicate that both the thawing regime and the time the samples stay in refrigeration, influence the observed trends significantly. The general drip loss enhancement seen after thawing as well as the increasing meat toughness, judged subjectively, must be due to cold-shortening and/or thaw rigor phenomena.     

Estimating calcium in mechanically deboned poultry meat by oxidimetry and atomic absorption spectrophotometry

In samples taken over six months from 68 lots of mechanically deboned poultry meat, from several Dutch meat producers, average calcium content by atomic absorption spectrophotometry (AAS) was 2·36 g/kg. As AAS requires expensive equipment, laboratories less well equipped need something less sophisticated. A series of ten meat samples with increasing calcium content was analysed by two oxidimetric methods and by AAS. For in-plant quality control to a maximum calcium content of 2·5 g/kg the oxidimetric methods seemed sufficiently precise and repeatable because a confidence interval of 0·40 g/kg (P = 0·95) was found for analysis on duplicate subsamples. The relationship between the oxidimetric method of Peter (1966) and AAS could not be explained completely, whereas the oxidimetric method of AOAC corresponded well with AAS. There was a significantly (α = 0·01) higher correlation (r = 0·9996) between the AOAC method and AAS, so that the AOAC method is preferred more than that of Peter.     

肉类制品的质构特性及其研究进展

探讨TPA测试肉制品质构特性的指标、意义和形成机理,并对内制品的质构特性及其影响因素进行综述.针对我国肉制品质构研究存在的问题,提出质构参数标准化研究的必要性,建议用肉制品质构指标取代感官评价方法指导肉制品研发工作.     

Microbiological and lipid oxidation studies on mechanically deboned turkey meat treated by high hydrostatic pressure

Mechanically deboned turkey meat was treated by high hydrostatic pressure. Two treatments were applied, 200 MPa (20 min) for chilled, 400 MPa (20 min) for frozen meat, thawed-up for the treatment, then re-frozen for storage. In both cases, storage experiments were made (15 days and 8 months respectively). The changes in microbiological status and lipid oxidation parameters, as well as cholesterol oxidation products (COPs) concentration were examined. These factors could affect the shelf life, the safety and sensory quality of products. Due to the effects of treatments, a significant reduction in the numbers of viable cells, an increase in thiobarbituric acid reactive substances (TBARs) values and formation of COPs could be observed.     

Bacteriological quality assurance (BQA) of mechanically deboned meat (MDM)

Adequacy of bacteriological quality assurance during the commercial production of mechanically deboned meat (MDM) was assessed. Lax standards of hygiene during production were observed, resulting in high numbers of Staphylococcus aureus, viz. 10⁴ to 10⁵ cfu g⁻¹, and severe contamination with Enterobacteriaceae: 10⁵ to 10⁶ cfu g⁻¹. These data indicate that measures of hygiene observed during boning of carcasses and during collection, storage and transport of bones or poultry parts should be markedly tightened, while conditions of refrigerated storage of raw materials and MDM should be improved. Use of bones of poor sensory quality (discoloration, abnormal smell) generally resulted in MDM of inferior bacteriological quality.

Phage typing, biotyping and assessment of enterotoxin production was carried out with 136 St. aureus cultures, isolates from mechanically deboned pork produced at one plant. Fifty-five per cent of the isolates was not typable, 28% was typable with human phages, 8% with bovine phages. The majority of the strains could not be explicitly assigned to any Meyer and/or Hájek and Mar álek types. Applying the simplified system of Devriese to eighteen strains isolated in our investigation, ten were found to belong to the poultry ecovar, one to the bovine ecovar, while seven strains were non-host specific. None of the isolates produced enterotoxins A–E.

Microbiological inspection of end products is recommended as part of an integrated quality assurance system. The following reference values for the final product (maximal colony counts to be expected under GMP conditions expressed as 95th percentile) were calculated: Pig MDM: log₁₀ mesophilic colony count 6·8 and log₁₀ cfu mesophilic Enterobacteriaceae g⁻¹ 4·8; Poultry MDM: log₁₀ mesophilic colony count 6·6 and log₁₀ cfu mesophilic Enterobacteriaceae g⁻¹ 4·7.     

复合变性淀粉提高鸡胸肉保水率的研究

报道了利用复合变性淀粉提高鸡胸肉保水率的研究。通过单因素实验，分别研究了磷酸酯玉米淀粉、磷酸酯木薯淀粉、交联马铃薯淀粉、交联木薯淀粉、醋酸酯玉米淀粉添加量对胸肉的吸水率和失水率的影响。根据单因素实验结果，进行了正交实验，验证得出最优配方为磷酸酯玉米淀粉为0．4％，磷酸酯木薯淀粉为0．8％，交联马铃薯淀粉为0．5％，交联木薯淀粉为0．6％及醋酸酯玉米淀粉为0．06％。经过验证实验所得到的吸水率和失水率的数据分别为7．9％和13．8％。