结冷胶对猪肉糜凝胶特性的影响

结冷胶作为脂肪替代物可有效降低猪肉糜中的脂肪含量,对增强低脂肉糜制品品质具有良好作用。本试验将结冷胶与水混合制备结冷胶胶体,研究结冷胶胶体替代猪背膘对猪肉糜凝胶特性及品质的影响。结果表明:添加结冷胶胶体显著影响(p<0.05)猪肉糜的蒸煮得率、色泽、质构、流变性和感官特性。结冷胶胶体添加量为0、0.3%和0.5%(质量分数)时,猪肉糜的蒸煮得率和质构差异不显著(p>0.05),0.7%时,蒸煮得率、L*值、硬度、弹性、内聚性和咀嚼性显著降低(p<0.05)。初始储能模量(G')随着结冷胶胶体添加量的增加而降低;结冷胶胶体添加量为0、0.3%和0.5%猪肉糜80 ℃时的G'差异不显著(p>0.05),结冷胶胶体添加量为0.7%时,G'显著下降(p<0.05)。综上所述,结冷胶胶体添加量为0.3%、0.5%时可降低猪肉糜中猪背膘的添加量。     

Gel—sol transition in gellan gum solutions. II. DSC studies on the effects of salts

The thermal properties of sodium form gellan gum solutions with and without sodium chloride, potassium chloride, calcium chloride and magnesium chloride were studied by differential scanning calorimetry (DSC). The DSC cooling or heating curves for 1% gellan gum solutions without salt showed a single exothermic or endothermic peak at ~30°C. DSC cooling curves showed a single exothermic peak, with the setting temperature (Ts) shifting to progressively higher temperatures with increasing concentration of the added NaCl or KCl. At low concentrations of NaCl or KCl, DSC heating curves showed a single endothermic peak; however with more addition of salt the endothermic peak gradually developed a bimodal character and eventually split into more than two distinct peaks. The onset of detectable splitting occurred at a high salt concentration which coincided with that at which elastic gels are formed at even a higher temperature as was observed by viscoelastic measurements. With a sufficient addition of monovalent cations the endothermic curve became again a single peak shifting to higher temperatures. In the presence of divalent cations, although Ts shifted to higher temperatures with increasing concentration of added CaCl₂ or MgCl₂, the melting temperature (Tm) in heating DSC curves shifted to higher temperatures (up to a certain temperature) and then shifted to lower temperatures with increasing concentration of salt. With increasing concentration of CaCl₂ or MgCl₂, the exothermic and endothermic enthalpies estimated for a main peak increased up to a certain salt concentration and then decreased; however many other peaks were observed at higher temperatures. The endothermic peaks for gels with excessive divalent cations were too broad to be resolved from the baseline; in contrast the exothermic peaks were much sharper and readily recognized. In comparing thermal properties with rheological properties, gellan gum solutions with excessive divalent cations form firm gels on cooling to below the setting temperature, and then it was difficult to remelt them. This was quite different from the behaviour of thermoreversible gels formed in the presence of monovalent cations. It seems that the mechanism of gel formation in gellan gum with divalent cations is markedly different from that with monovalent cations.     

Low-Fat Bologna and Beaker Sausage: Effects of Carrageenans and Chloride Salts

Two meat products, regular bologna and bologna-like beaker sausage, were used to test performance of low-fat bologna batters prepared with two chloride salts (NaCl or KCl) and two carrageenan types (kappa or lambda). In the beaker sausage, two carrageenan-salt combinations lowered cooking loss compared to controls, and lambda-carrageenan in the presence of potassium cations was most effective. In regular bologna, none of the carrageenan-salt combinations lowered the cooking loss usually resulting with large amounts of added water. Also, treatments with lambda-carrageenan were less firm than high-fat or low-fat controls.     

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.     

肉制品加工中镁盐部分替代氯化钠的应用研究进展

钠盐的超量摄入是目前食品安全领域关注的热点。由于肉品感官与质量安全等因素限制,肉品加工中简单减少或消除氯化钠的应用并不可行。本文主要对镁盐对人体健康的影响、镁盐在肉制品中的应用机理进行综述,探讨在肉制品加工中使用镁盐部分替代氯化钠的可行性,为新型低钠盐肉制品的开发与质量控制提供科学理论依据。     

鸭腿减盐滚揉腌制过程中的传质动力学

用减盐（30% KCl＋70% NaCl）和氯化钠食盐（即普通食盐,NaCl质量分数≥99.1%）分别腌制肉鸭鸭腿,测定滚揉腌制过程中鸭腿肉总质量、水分质量分数、食盐质量分数变化情况,获得鸭腿肉在不同食盐腌制时的传质动力学数据,并进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳实验,研究不同食盐滚揉腌制过程对鸭腿肉蛋白质的影响。结果显示：氯化钠腌制和减盐腌制中鸭腿肉的总质量变化量（ΔMt0）、水分质量分数变化量（ΔMtw）以及盐分含量变化量（ΔMts）均与腌制时间的平方根（t0.5）呈现出较好的相关性,而且前4 h ΔMt0、ΔMtw以及ΔMts增长较快;氯化钠腌制和减盐腌制的有效扩散系数De分别为4.432×10－8 m2/s和4.462×10－8 m2/s,相差较小;十二烷基硫酸钠-聚丙烯酰胺凝胶电泳图谱显示两种腌制方法肌原纤维蛋白都在不断降解。综上,减盐腌制和氯化钠腌制相比,对传质速率并无明显影响。     

Effect of Gums on Low-Fat Meat Batters

The effects of adding Iota-carrageenan, kappa-carrageenan, guar gum, locust bean gum, xanthan gum, methylcellulose, and a locust bean gum/kappa carrageenan mixture to low-fat, high moisture meat batters were investigated. The methylcellulose treatment showed an increase in weight losses between 60° and 70°C, while other treatments remained similar throughout heating. Xanthan gum and guar gum at 0.2% altered textural parameters as determined by texture profile analysis. Increasing the concentration of xanthan gum decreased batter hardness without affecting batter stability. Sensory evaluation indicated that low-fat frankfurters (11–12% fat) were as acceptable as control frankfurters (27% fat).     

Influence of sodium replacement on the salting kinetics of pork loin

The partial replacement of sodium chloride by other salts has been proposed as a possible strategy to reduce the sodium content of cured meat products. Nevertheless, there is very little knowledge as regards the influence of salts other than sodium chloride on salting kinetics.The aim of this study was to evaluate the effect brought about by substituting sodium chloride with potassium, calcium and magnesium chloride on the salting kinetics of dry cured loins. The results showed very important changes in the salting pattern depending on the type of salts. Partial substitution of sodium affected both water and ion transport during the salting process. The presence of KCl decreased water loss while CaCl₂ and MgCl₂ had the opposite effect. However, replacement of up to 50% NaCl by KCl had no significant effect on the salting kinetics in the case of the control formulation. Calcium and magnesium cations penetrated with difficulty into the muscle remaining in the brine formed during the pile salting process. Moreover, the presence of calcium and magnesium cations considerably reduced the sodium and potassium content of the salted loin.     

食盐与高温对猪肉糜品质的影响

本文研究不同食盐添加量与高温蒸煮对猪肉糜品质的影响。通过对猪肉糜的蒸煮得率、色泽、质构、流变等进行分析,研究不同食盐添加量(1%、2%、3%)和蒸煮高温(105、115和125 ℃)对猪肉糜品质的影响。结果表明:随着温度的升高,相同食盐添加量猪肉糜的a*值、b*值显著升高(p<0.05),L*值、蒸煮得率、弹性、内聚性下降显著(p<0.05);相同温度下,1%食盐处理组的L*值最小,a*值和b*值最大;3%食盐添加量显著提高(p<0.05)蒸煮肉糜的硬度、弹性和内聚性。加热到105 ℃以后,随着温度升高不同食盐添加量猪肉糜的储能模量(G')呈下降趋势,3%食盐添加量猪肉糜的G'最高。综上所述,高温能够降低猪肉糜的品质,3%食盐添加量在105 ℃时猪肉糜的品质最佳。     

Serum release boosts sweetness intensity in gels

This paper describes the effect of serum release on sweetness intensity in mixed whey protein isolate/gellan gum gels. The impact of gellan gum and sugar concentration on microstructure, permeability, serum release and large deformation properties of the gels was determined. With increasing gellan gum concentration the size of the pores present in the protein network, the permeability and the serum release increased, as well as the Young's modulus, the fracture stress and the fracture strain. Increasing the sugar concentration induced an increase of the pore size, but resulted in a decrease of permeability and serum release. The addition of sugar resulted in gels with a higher Young's modulus and a lower fracture strain. This effect was more evident at higher gellan gum concentrations. By changing the protein concentration of the gels, a set of samples was prepared exhibiting constant large deformation properties but varying in serum release and sugar concentration. Serum release significantly boosted sweetness intensity. For example, the sweetness scores for gels with 12% serum release were the same as for gels with 2% serum release but 30% higher sugar concentration. The results indicate that serum release is a tool to compensate for the loss taste intensity related to the reduction of sugar and salt in gelled foods.     

Rates of Heating and lnstron Measurements for Turkey Batters with Sodium Salts of Nitrite, Chloride and Phosphate

Electrical resistance heating at two voltage levels was used to heat muscle batters containing a variety of sodium salts. Peak heights or depths from Instron curves indicated resistance of heated muscle batters to expansion or contraction. Batters heated at the higher voltage had increased peak heights, higher temperatures at which the batters reached that peak and decreased peak depths. Batters with sodium nitrite became less fluid in the initial stages of heating and expanded more with heating than those with water only. Sodium chloride increased peak heights and increased the temperatures at which the batters reached those peaks. Batters with sodium chloride and sodium tripolyphosphate were the least fluid during heating and began to expand at the lowest temperatures.     

Carrageenans in Beaker Sausage as Affected by pH and Sodium Tripolyphosphate

We investigated effects of meat pH or sodium tripolyphosphate (STPP) on performance of carageenans (kappa, iota or lambda) in low-fat beaker sausage model systems. Adding STPP or using high-pH meat affected performance of the meat batter in similar ways. High-pH meat batters or those containing STPP had lower force values when extruded, lower cooking losses, and were firmer when cooked. The addition of lambda-carrageenan produced the softest texture. Kappa- and iota-carrrageenan improved water retention of low-pH meat batters. After staining, light microscopy revealed different structural effects of the carrageenans.     

Reduced‐sodium cheeses: Implications of reducing sodium chloride on cheese quality and safety

Sodium chloride (NaCl) universally well‐known as table salt is an ancient food additive, which is broadly used to increase the storage stability and the palatability of foods. Though, in recent decades, use of table salt in foods is a major concern among the health agencies of the world owing to ill effects of sodium (Na) that are mostly linked to hypertension and cardiovascular diseases. As a result, food scientists are working to decrease the sodium content in food either by decreasing the rate of NaCl addition or by partial or full replacement of NaCl with other suitable salts like potassium chloride (KCl), calcium chloride (CaCl₂), or magnesium chloride (MgCl₂). However, in cheese, salt reduction is difficult to accomplish owing to its multifaceted role in cheese making. Considering the significant contribution in dietary salt intake (DSI) from cheese, researchers across the globe are exploring various technical interventions to develop reduced‐sodium cheeses (RSCs) without jeopardizing the quality and safety of cheeses. Thus, the purpose of this study is to provide an insight of NaCl reduction on sensory, physicochemical, and technofunctional attributes of RSCs with an aim to explore various strategies for salt reduction without affecting the cheese quality and safety. The relationship between salt reduction and survival of pathogenic and spoilage‐causing microorganisms and growth of RSCs microflora is also discussed. Based on the understanding of conceptual and applied information on the complex changes that occur in the development of RSCs, the quality and safety of RSCs can be accomplished effectively in order to reduce the DSI from cheese.     

Effects of salt reduction on the rheological and gelation properties of beef, pork and poultry meat batters

The gelation and rheological properties of beef, pork and poultry meat batters as affected by salt reduction (2·50, 1·25 and 0·00%) were studied by using a Haake rotational viscometer and a thermal scanning rigidity monitor. Beef batters showed a decrease in shear stress with the decrease in salt levels at both high and low shear rates. Pork batter showed a mixed behavior (no definite trend in shear stress versus shear rate) and the poultry meat batters showed a Bingham pseudoplastic behavior, except for the no-salt treatment. During heating the beef batters showed the highest G values followed by the pork and the poultry meat batters. The rigidity modulus profiles exhibited two major transition temperatures at 47-53°C and at 64-76°C. Beef batter with 2·50% salt developed the highest average G value (16·6 kPa) and the poultry batter with 2·50% salt the lowest (7·3 kPa).     

EFFECT OF ADDED SALT ON TEXTURAL PROPERTIES OF HEAT-INDUCED GELS MADE FROM GUM–PROTEIN MIXTURES

Large deformation rheological tests were employed to determine the textural differences in heat‐induced gel systems. Three different large deformation rheological methods (viscosity index and apparent elasticity, texture profile analysis (TPA) and torsional fracture) were employed to study the dependence of the ion type on the textural properties of heat‐induced mixed protein–gum gels. Protein–gum mixed solutions were prepared with bovine serum albumin (BSA) or egg white albumin (EWA) (20% w/v) with κ‐carrageenan (KCG), gellan (GLN) or xanthan gums (XNT) (0.5% w/v) at 0.1 M sodium chloride (NaCl), potassium chloride (KCl) or no added salt. Despite inherent differences in protein type, the main effect on the textural properties evaluated was for the kind of salt added, since potassium ions, with a strong influence on KCG and GLN gelation, affected the parameters related to the structure or hardness of the samples. There was no significant effect on parameters associated with sample ductility or elasticity. GLN formed stronger gels than KCG, whereas XNT did not perform as well in gel formation since it does not contribute to protein matrix formation. The results indicated that potassium may be substituted for sodium ions at low ionic strengths in foods where the incorporation of KCG or GLN helps to improve texture and related features.     

Influence of Various Salts and Water Soluble Compounds on the Water and Fat Exudation and Gel Strength of Meat Batters

Meat batters were prepared in which the sodium or chloride from salt was replaced by other ions. Then the functional properties of the batters were determined by measuring water and fat exudation, and gel strength. Generally cations from groups IA and IIA of the periodic table equalled or surpassed the batters made with sodium only, whereas other cations decreased water binding. Of the anions, bromide, orthoand pyrophosphates, and citrate increased water retention. Zinc chloride increased fat exudation greatly. Magnesium chloride and sodium pyrophosphate increased the gel strength. Magnesium and calcium chlorides made good batters although they caused a drop of approximately 0.25 pH units. Sodium thiosulfate, sodium borohydride, starch, sucrose, glycerol, arginine and urea improved the water binding and gel strength, while nonionic detergents, monoglycerides and alcohols were very detrimental.     

Determining salt concentrations for equivalent water activity in reduced-sodium cheese by use of a model system

The range of sodium chloride (salt)-to-moisture ratio is critical in producing high-quality cheese products. The salt-to-moisture ratio has numerous effects on cheese quality, including controlling water activity (a_w). Therefore, when attempting to decrease the sodium content of natural cheese it is important to calculate the amount of replacement salts necessary to create the same a_w as the full-sodium target (when using the same cheese making procedure). Most attempts to decrease sodium using replacement salts have used concentrations too low to create the equivalent a_w due to the differences in the molecular weight of the replacers compared with salt. This could be because of the desire to minimize off-flavors inherent in the replacement salts, but it complicates the ability to conclude that the replacement salts are the cause of off-flavors such as bitter. The objective of this study was to develop a model system that could be used to measure a_w directly, without manufacturing cheese, to allow cheese makers to determine the salt and salt replacer concentrations needed to achieve the equivalent a_w for their existing full-sodium control formulas. All-purpose flour, salt, and salt replacers (potassium chloride, modified potassium chloride, magnesium chloride, and calcium chloride) were blended with butter and water at concentrations that approximated the solids, fat, and moisture contents of typical Cheddar cheese. Salt and salt replacers were applied to the model systems at concentrations predicted by Raoult's law. The a_w of the model samples was measured on a water activity meter, and concentrations were adjusted using Raoult's law if they differed from those of the full-sodium model. Based on the results determined using the model system, stirred-curd pilot-scale batches of reduced- and full-sodium Cheddar cheese were manufactured in duplicate. Water activity, pH, and gross composition were measured and evaluated statistically by linear mixed model. The model system method accurately determined the concentrations of salt and salt replacer necessary to achieve the same a_w as the full-sodium control in pilot-scale cheese using different replacement salts.     

一种水包油包胶型乳液的制备及其在乳化肠中的应用

以结冷胶和无水氯化钙为内水相凝固剂,酪蛋白酸钠为外水相乳化剂,制备一种水包油包胶（S/O/W）型 乳液。以多重乳液粒径和分布为指标,研究酪蛋白酸钠添加量对S/O/W型多重乳液加工适应性的影响。结果表明： 正交试验得到S/O型单重乳液最佳制备条件为：内水相中结冷胶添加量0.2%、无水氯化钙添加量0.5%;内水相乳化 剂聚甘油蓖麻醇酯添加量2.5%;油相为精炼猪油,油水体积比3∶2;剪切速率17 500 r/min,剪切时间1.5 min。将制 得的S/O型单重乳液与不同添加量酪蛋白酸钠混合制得S/O/W型多重乳液。当酪蛋白酸钠添加量0.1%时,S/O/W型 多重乳液粒径符合加工要求,且贮藏、热处理、剪切稳定性较好。以多重乳液替代猪脂肪制备的低脂乳化肠与高脂 （精炼猪油含量20%）乳化肠外观不存在明显差异;微观结构观察结果表明,多重乳液在乳化肠中包裹良好、分布 均匀。     

Physical and sensory properties of regional sea salts

Seven varieties of sea salt and a Kosher control were characterized by composition, various physical properties and rates of dissolution in artificial saliva. These measures were compared to sensory time–intensity data in which the temporal profile of salt taste of the sea salt crystals was measured by a trained panel (n = 12). Salts contained either the same or less sodium than the Kosher salt. Three salts contained similar sodium contents as the Kosher control while True Kona contained the lowest sodium content with 16.75% less sodium than Kosher salt. Significant differences were observed among salts for their rates of dissolution, temporal perception of salt taste as well as composition. From a sensory perspective, there were few differences in maximum salt taste intensity. There were, however, some differences in the salts' time–intensity profiles. Red Aelea exhibited the lowest maximum intensity but also exhibited the longest duration of salt taste intensity in comparison to all other salts. Rates of dissolution were found to be negatively correlated with time to maximum salt taste intensity and overall duration of salt taste. Significant differences were found between the size of the salt particles and size was strongly correlated with rates of in-vitro dissolution as well as with a variety of time–intensity sensory measures Based on the fact that salts did not show large differences is taste intensity and many of the salts did not contain less sodium than the Kosher control, using the studied sea salts as a sodium reduction strategy is not viable.