Water holding capacity of sodium-reduced chicken breast myofibrillar protein gel as affected by combined CaCl2 and high-pressure processing

The water holding capacity (WHC) of sodium-reduced (0.3 m sodium chloride, corresponding to the salt percentage (w/v) of 1.755%) myofibrillar protein (MP) gel in response to combined calcium chloride (CaCl₂, 20, 60, 100 mm ) and high-pressure processing (HPP, 200 MPa, 10 min) was investigated. The results showed that 200 MPa + 20 mm CaCl₂ synergistically increased the WHC of MP gel via reducing particle size of MP solutions, strengthening hydrogen-bonding and disulphide-bonding, promoting formation of β-sheet and uncoiling of α-helix, exposing tryptophan residues, enhancing hydrophobic interactions of aliphatic residues and forming a compact and continuous networked gel structure. However, high concentrations (≥60 mm ) of CaCl₂ could attenuate the enhancing effects of HPP on the WHC by inducing decreased hydrogen bonds, fewer tryptophan residues exposed and coarser and aggregated gel structures with large cavities. Therefore, a combined moderate HPP and low concentration of CaCl₂ is a potential alternative for developing sodium-reduced meat products.     

Effects of High-Pressure Processing on the Cooking Loss and Gel Strength of Chicken Breast Actomyosin Containing Sodium Alginate

The effects of high-pressure processing (HPP) (0–400 MPa for 10 min) on the cooking loss (CL), gel strength, and thermal gelling mechanism of chicken breast actomyosin solution containing 0.5 % (w/v) sodium alginate (AS-SA) were investigated. The results showed that HPP could significantly increase (P?相似文献   

Effect of high pressure processing on the gel properties of salt-soluble meat protein containing CaCl2 and κ-carrageenan

The effects of high pressure processing (HPP) on the water-binding capacity and texture profile (TPA) of salt-soluble meat protein (SSMP) containing 0.2% CaCl₂ and 0.6% κ-carrageenan (SSMP-CK) gels were investigated. The results showed that 300–400 MPa improved water-binding capacity and decreased TPA parameters of SSMP-CK gels (P < 0.05), while 100 MPa could increase hardness and chewiness of the gels. The thermal transition temperature peak for the myosin head (T_peak1) of SSMP disappeared on addition of CaCl₂ and κ-carrageenan. 300 MPa produced a new peak, and caused a shift of the NH-stretching left peak and amide I and the disappearance of NH-stretching right peak. The destruction of network structure and the weakening of molecular interaction within the pressurized gels could result in the decrease of TPA parameters. Thus gelling properties could be modified by HPP, κ-carrageenan and Ca^2 +. It is of interest to develop low-fat and sodium-reduced meat products.     

High pressure processing of meat batters with added walnuts

Various model systems were designed in order to analyse the way in which addition of different levels of walnut (0, 10, 20%) and processing by high pressure (HPP) (400 MPa for 10 min at 10 °C) influenced the physico‐chemical properties of cooked (70 °C for 30 min) meat batters. The addition of walnut increased the fat level and decreased the moisture content in the meat batters. All of the meat batters exhibited good water and fat binding properties. The hardness, cohesiveness, springiness and chewiness of cooked products were reduced by addition of walnut but were unaffected by HPP. Incorporation of nuts in meat products can potentially be used to confer cardiac health benefits.     

Tenderness improvement of reduced-fat and reduced-salt meat gels as affected by high pressure treating time

This study investigated the effect of high-pressure treating time (HPTT) on the tenderness of reduced-fat reduced-salt (RFRS) meat gels. The result of shear force value showed that the RFRS meat gels exhibited excellent tenderness treated with 200 MPa for 3 min. The mechanism of tenderness enhancement was revealed from the perspective of water migration characteristics in meat batters. After HPP, the characteristics of water molecules in meat batters were investigated using low-field nuclear magnetic resonance (LF-NMR) T₂ relaxometry. The datas of T₂ relaxation time and peak area indicated the free water changed into immobilized water significantly. The result of principal components analysis showed that the sample treated with a proper HPPT (3 min) was significantly different from the others. The tenderness of RFRS meat gel products was improved with the application of 200 MPa, especially treated with 3 min. The improvement of tenderness could be ascribed to the increase of immobilized water. The possible increase of the diameter in three-dimensional gel network might lead to more water molecules entrapped.     

低场核磁共振研究高压处理对乳化肠特性的影响

以低温乳化肠为材料,对0.1 ～ 400 MPa 压力处理组肉糜进行扫描电镜观察和低场核磁共振检测,评估加热后的感官特性,并进行相关性分析,从显微结构和水分子弛豫特性变化角度揭示高压处理对乳化肠感官特性改善的原因。结果表明：与对照组相比,压力从100 MPa 增大到200 MPa,感官特性得分增加,而200 MPa 到400 MPa得分减小（P ＜ 0.05）;扫描电镜结果显示各组肉糜显微结构存在明显差异;T2 弛豫结果显示,实验组T21 峰面积大于对照组而T22 峰面积小于对照组（P ＜ 0.05）,T21 弛豫时间在压力从100 MPa 增大到200 MPa 过程中升高,而在200 MPa 到400 MPa 降低（P ＜ 0.05）;相关性分析表明,感官特性各指标与T21 弛豫时间及其峰面积正相关,与T22 峰面积负相关（P ＜ 0.05）。因此,高压处理使自由水部分转化为不易流动水,并影响不易流动水与肉糜蛋白的结合程度,而转化比例和结合程度的强弱又会显著影响肉糜微结构及其加热后的感官特性。     

Combination treatment of high-pressure and CaCl2 for the reduction of sodium content in chicken meat batters: effects on physicochemical properties and sensory characteristics

A combination of high-pressure processing (HPP, 200 MPa, 10 min) and CaCl₂ (0.2%, w/w) on the cooking loss (CL), expressible moisture (EM), textural properties (hardness, springiness, cohesiveness, chewiness and firmness) and sensory attributes of reduced-sodium (1.25% NaCl) chicken meat batters (RCMB) was investigated. The results revealed that combining HPP with CaCl₂ significantly decreased EM, elevated sensory properties and acted synergistically in reducing CL and improving hardness, chewiness and firmness, which enabled RCMB to obtain quality characteristics similar to those with high salt (2.5% NaCl) content. These changes brought about by combined HPP and CaCl₂ could be attributed to increased apparent viscosity and proportion of immobilised water, enhanced rheological (elastic) properties and a denser, homogeneous protein gel network with evenly dispersed small fat globules. It is interesting to take advantage of the synergy between moderate HPP and low concentrations of CaCl₂ to develop meat products with reduced sodium content.     

Effect of high pressure processing on heat-induced gelling capacity of blue crab (Callinectes sapidus) meat

There has been increasing use of High pressure processing (HPP) in the fishery industry since this technology facilitates shellfish shucking. Nevertheless, there is limited information about the effect of HPP on protein functional properties of some shellfish. The aim of this study was to evaluate the effect of 100, 300 and 600 MPa/5 min on the gelling capacity of heat-induced (40 °C/30 min + 90 °C/20 min) blue crab (Callinectes sapidus) meat. HPP treatment resulted in crab meat gels with a lighter and reddish colour as compared to the control. HPP at 600 MPa induced the formation of high molecular aggregates from the denaturation-aggregation of myosin heavy chain. Pressurization at 100 MPa promoted the shift of α-helix structures to β-sheet and β-turn as compared with the other pressure levels. TPA values were higher in gels made at 100 MPa than at 300 or 600 MPa. Low pressure levels, then, increased the heat-induced gelling capacity of crab meat, improving the texture through modification of its protein structure.Industrial relevanceHigh pressure processing (HPP) technology has been successfully applied to several seafood products, both for processing and storage. However, in the case of blue crab meat it is important to study the effect of HPP on protein functional properties such as gelling capacity in order to optimize processing parameters for the preparation of high-quality restructured products. This paper reports the development of a HPP process (100, 300 and 600 MPa/5 min 40 °C/30 min + 90 °C/20 min) prior to thermal gelling for the preparation of crab meat gels. The application of 600 MPa produced considerable protein aggregation of gels, whereas with pressures below 300 MPa protein functionality can be modified to produce crab meat gels with adequate brightness, TPA values and a fresh, high-quality appearance. These results could provide a basis for further pressurization applications in the crab industry to create new seafood product analogues based on this kind of crab meat.     

超高压处理对鳙鱼质构特性的影响

研究不同超高压条件(150、300、450MPa,保压15min)对鳙鱼质构特性的影响。结果表明,300MPa和450MPa处理可以显著提高鱼肉的粘着性和咀嚼性(p<0.05),优化感官品质。观察鱼肉的超微结构发现,用450MPa处理后出现明显的蛋白质胶凝化现象。用300MPa和450MPa处理后降低了肌原纤维断裂指数(p<0.01)和持水力,提高了鱼肉的pH值(p<0.01)。因此超高压处理在改良鳙鱼肉质方面具有潜在的应用价值。     

High pressure/thermal treatment of meat batters prepared from freeze-thawed pork

Various meat batters were prepared from pork subjected to different freeze–thaw cycles. These batters were pressurized (300 MPa, 30 min) at low, non-denaturing temperature (10°C) followed by heating (70°C) (PLT+H) and at high, denaturing temperature (70°C) (HUPC). Nonpressurized (NP), heated-only (70°C) sample were also produced. Freezing of meat influenced water binding and textural properties of meat batters; the influence on texture was affected by thermal and pressure conditions. Pressure prior to heating produced a coarse, irregular and loose protein matrix, favoring the formation of weaker gel structures than were found in non-pressurized samples. Pressurization at denaturing temperatures reduced the level of protein denaturation induced by the thermal treatment. The resulting gel structures had better water binding properties but were weaker than non-pressurized samples and samples pressurized prior to heating.     

Application of high pressure processing to improve the functional properties of pale, soft, and exudative (PSE)-like turkey meat

Improvement of functional and rheological properties of turkey breast meat proteins with different ultimate pHs at 24 h post-mortem (pH₂₄) was attempted using high pressure processing (up to 200 MPa for 5 min at 4 °C). Pressures of 50 and 100 MPa were found to increase the water holding capacity of low pH meat. At these pressures, higher protein surface hydrophobicity and greater exposure of sulfhydryl groups were evident. These elements may have contributed to improved water retention properties of the treated protein. The formation of a better gel network was also evident at 50 and 100 MPa as revealed by the dynamic viscoelastic behavior. Application of high pressure significantly (P < 0.05) increased total protein solubility in both low and normal pH meats. Aggregation of myofibrillar proteins increased in low pH meat at higher pressure (200 MPa) as revealed by SDS-PAGE profile.

Industrial relevance

A major concern in the poultry industry is reduced meat functionality, such as low water holding capacity (WHC) in low pH poultry meat leading to reduced yield causing economic loss in the production of further processed products. An alternative technology to reduce salt and improve water retention properties is by the application of high pressure processing (HPP) to produce healthier food products.     

High pressure induced changes in beef muscle proteome: Correlation with quality parameters

The relationship between pressure induced changes on individual proteins and selected quality parameters in bovine longissimus thoracis et lumborum (LTL) muscle was studied. Pressures ranging from 200 to 600 MPa at 20 °C were used. High pressure processing (HPP) at pressures above 200 MPa induced strong modifications of protein solubility, meat colour and water holding capacity (WHC). The protein profiles of non-treated and pressure treated meat were observed using two dimensional electrophoresis. Proteins showing significant differences in abundance among treatments were identified by mass spectrometry. Pressure levels above 200 MPa strongly modified bovine LTL proteome with main effects being insolubilisation of sarcoplasmic proteins and solubilisation of myofibrillar proteins. Sarcoplasmic proteins were more susceptible to HPP effects than myofibrillar. Individual protein changes were significantly correlated with protein solubility, L*, b* and WHC, providing further insights into the mechanistic processes underlying HPP influence on quality and providing the basis for the future development of protein markers to assess the quality of processed meats.     

Role of cathepsin D activity in gelation of chicken meat heated under pressure

The role of cathepsin D activity in gelation of chicken meat batters (400 MPa/30 min/70 °C) heated-under pressure was investigated, using a specific inhibitor, pepstatin, dissolved in dimethyl sulphoxide (DMSO)/acetic acid (9:1 v/v). Thermal treatment (70 °C/30 min) produced less thermal inactivation of cathepsin D activity at 400 MPa than at atmospheric pressure. Heating, under pressure conditions, produced gels which were less hard and chewy than those produced at atmospheric pressure. Irrespective of the pressure, the presence of the inhibitor solvent influenced the thermal gelation of meat batters, facilitating the formation of harder, chewier gels.     

High-pressure-cooked Low-fat Pork and Chicken Batters as Affected by Salt Levels and Cooking Temperature

The application of high pressure (200 and 400 MPa, 30 min) favored water and fat binding properties of chicken and pork batters even at low ionic strength. Textural properties of meat batters (particularly hardness and chewiness, and to a lesser extent springiness and cohesiveness) were influenced by cooking temperature. High pressures influenced the texture of batters, so that pressurized samples were less hard, cohesive, springy or chewy than nonpressurized samples; this effect was not related to on salt concentration. High pressure treatment limited the formation of gel structures, which probably was associated with its preserving effect against thermal denaturation of meat proteins.     

Effect of salt content on gelation of normal and wooden breast myopathy chicken pectoralis major meat batters

This study investigated the effects of salt content (0–4%) on water holding capacity (WHC), textural characteristics, rheological properties, and microstructure of cooked normal (NOR) and wooden breast (WB) chicken meat batters. Results indicated with 0–2% salt addition, the WB batters had significantly lower WHC and storage modulus (G’) compared with the NORs (P < 0.05). However, these differences were eliminated when salt contents were increased to 3% or 4%. In addition, the NORs formed more regular and pored networks than the WBs (0–2%). Salt level significantly affected the textural properties of both batter types (P < 0.05). The hardness of the WB batters was lower than NORs at all NaCl levels (P < 0.05). Overall, compared with NORs, the WB batters showed inferior gelation properties at salt contents of 0–2%, while increasing salt content to 3–4% can improve the WHC and microstructure of gels.     

Frozen storage of high-pressure- and heat-induced gels of blue whiting (Micromesistius poutassou) muscle: rheological, chemical and ultrastructure studies

This paper examines the influence of frozen storage over 34 weeks on the rheological properties as well as the chemical and microstructural characteristics of gels made from muscle of blue whiting (Micromesistius poutassou) subjected to different gelling treatments entailing three combinations of pressure, temperature and time: 200 MPa, <10°C, 10 min (lot L), 375 MPa, 38°C, 20 min (lot H) and atmospheric pressure, 37°C, 30 min and then 90°C, 50 min (lot T). Freezing at –40°C caused certain changes in rheological parameters. In heat-induced gels, breaking deformation, elasticity and cohesiveness increased. Of the high-pressure-induced gels, breaking force increased and cohesiveness decreased in the gel formed at lower pressures, while the only change in the gel formed at higher pressure was some loss of elasticity. There was a general fall in water holding capacity (WHC) values. Lightness remained stable. In terms of protein solubility, there was an increase in covalent bonds in lot L. As for the ultrastructure, all gels matrixes were more disorganized as a result of freezing. In the course of frozen storage, the greatest changes in rheological parameters generally took place during the first 8 weeks, and in all the gels there was a decrease in WHC. In the heat-induced gel the changes were less marked over the storage period compared with those in the high-pressure-induced gels, but the heat-induced gel was more brittle and did not maintain maximum folding test scores. Covalent bonds increased and hydrophobic interactions decreased in all lots. The general appearance of the structure of gel T remained more homogeneous, while the pressurized gels exhibited more and larger cavities.     

High‐pressure processing‐induced conformational changes during heating affect water holding capacity of myosin gel

This study aimed to investigate the effects of high‐pressure processing (HPP) (0.1‐400 MPa for 9 min) on the water holding capacity (WHC) of heat‐induced rabbit myosin gel and structural changes during thermal treatment (25–75 °C). HPP at 100 MPa significantly increased the WHC (P < 0.05) and formed more regular and homogeneous three‐dimensional network. Myosin tails at 100 MPa unfolded completely during the thermal treatment, which was beneficial to form a high WHC gel network. However, myosin pressurised at 200 MPa and above formed a weak gel. Their heads were already aggregated before heating, preventing from subsequent thermal denaturation and aggregation. With the temperature increasing, unfolding of myosin tails was not sufficient for a filamentous network formation. These results suggested that HPP could modify the myosin structure and affect the gel formation during heating. The 100 MPa was the optimum pressure level for the WHC of rabbit myosin gel.     

增稠剂提高牛肉持水性的配方研究

肉的持水性指肉在冻结、冷藏、解冻、腌制、绞碎、斩拌、加热等加工处理过程中肉中的水分以及添加到肉中的水分的保持能力。肉的持水性直接关系到肉制品的质地、嫩度、切片性、弹性感,出品率等项质量指标和经济指标。为研究提高肉及肉制品的持水性,本文通过添加不同增稠剂(黄原胶、海藻酸钠、卡拉胶)对离心法测定牛肉持水性的影响,以单因素试验确定最佳添加量,并进行正交试验。确定显著提高牛肉持水性的最佳组合添加量为黄原胶0.2%,海藻酸钠0.2%,卡拉胶0.3%。     

High pressure-induced tapioca starch gels: physico-chemical characterization and stability

Gelatinization of tapioca starch (25% dry basis) was induced by high hydrostatic pressure processing (HPP) at 600 MPa under different time and temperature regimes (30 °C for 10, 20 and 30 min; 50 °C for 10 min; 80 °C for 10 min). Textural, thermal and structural properties of the gels were studied and their stability was evaluated after 28 days of refrigerated (4 °C) and frozen (−18 °C) storage. Thermally induced gels (90 ± 1 °C, 20 min, gel-T) were used as controls. HPP resulted in the formation of harder gels than thermal processing (more significantly at lower processing temperatures) partially preserving the granular structure of the native starch. Longer HPP treatments caused only a slight decrease in hardness that was significant only at longer processing times (30 min). DSC thermograms of high pressure-induced samples showed a more asymmetrical ice-melting peak than that of thermally induced gels. Asymmetry of the peak of HP treated samples was more pronounced in samples processed at lower than at higher temperature. A different starch–water and/or starch/starch interaction may be hypothesized. During storage, all samples became stiffer and the amylopectin recrystallization increased, more extensively in thermally induced than in HPP samples where a stronger starch–starch and/or starch/water interactions may have hindered the recrystallization process.     

大豆分离蛋白添加量对低盐木质化鸡肉糜凝胶特性的影响

探究大豆分离蛋白(soy protein isolates,SPI)添加量对低盐和正常盐木质化鸡胸肉糜凝胶特性的影响.实验设置正常鸡胸肉为对照组.将不同量(0％、1％、2％)SPI分别添加到含1％和2％食盐的木质化和正常鸡胸肉糜中,测定热诱导凝胶的质构特性、颜色、蒸煮损失、水分分布以及蛋白质二级结构等指标.结果表明:相...