乳化盐对再制马苏里拉乳酪品质的影响

乳化盐是再制乳酪的关键原料。通过测定烘焙功能性和流变性,研究乳化盐对再制马苏里拉乳酪品质的影响,结果表明,乳化盐对再制马苏里拉乳酪烘焙功能性有显著影响,随着型号为"JOHA PZ14"的复合磷酸盐添加比例的提高,再制马苏里拉乳酪融化性和油脂析出性增加,拉伸性先增加后降低,褐变性降低。选择型号为"JOHA PZ7":"JOHA PZ14"乳化盐=4:1时,再制马苏里拉乳酪烘焙功能性最接近天然马苏里拉乳酪。     

乳化盐及加工条件对再制干酪质地及理化特性的影响

研究乳化盐及加工条件对再制干酪质地及理化特性的影响。结果表明,增加乳化盐的用量、融化温度和延长搅拌时间明显降低了再制干酪的融化性(p<0.01),不同种类乳化盐在相同添加水平下,制得样品的融化性:焦磷酸钠>磷酸氢二钠>柠檬酸钠;增加乳化盐的用量和延长搅拌时间制得的样品硬度显著增加、黏着性显著减小(p<0.01),提高融化温度制得的样品硬度增加,但其黏着性差异不显著(p>0.01)。在添加量相同的情况下,柠檬酸钠制得样品的硬度和黏着性最大,焦磷酸钠使样品的硬度和黏着性最小。     

Textural Properties of Mozzarella Cheese Analogs Manufactured from Soybeans

Mozzarella cheese analogs were produced from soybeans or soy protein products, gelatin, gum arabic and other ingredients. The method for production of the cheese analog consisted of the following: (1) mixing at controlled temperatures to obtain a homogeneous mass, and (2) tempering at a temperature of 4°C for 24 hr. Several analog formulations were evaluated and the factors such as pH, fat content, salt content, influencing textural characteristics were studied with an Instron Universal testing machine and a modified Weissenberg test. The physical and functional properties of the final product were found to be similar to those of natural mozzarella cheese (low moisture part-skim) tested and evaluated with the same experimental methods.     

Calcium Bioavailability from Ripening Cheddar Cheese

Calcium bioavailability to rats was compared from CaCl₂ (28 mM), CaCO₃, fresh milk, milk adjusted to pH 5.35, and Cheddar cheese. The cheese was manufactured from pasteurized bovine milk and all doses were labeled extrinsically with ⁴⁵Ca and ⁴⁷Ca and administered orally to rats. One label (⁴⁵Ca) was added to milk before cheese manufacture and the other (⁴⁷Ca) was added to the cheese 24 h prior to dosing. Calcium bioavailability was determined by: 1) absorption measured by whole body counting, and 2) availability for bone metabolism assessed by bone radioactivity measurements. Calcium absorption averaged 76.8% and was not affected by length of ripening (p>0.05). Absorption from CaCl₂, CaCO₃, fresh milk, milk at pH 5.35, and the cheeses was similar. The two methods gave similar estimates of relative bioavailability. The ratio of ⁴⁷Ca absorption to ⁴⁵Ca absorption for any cheese sample was significantly greater than 1, indicating extrinsic labels added after processing may overestimate Ca absorption from cheese.     

Effects of pH on the Textural Properties and Meltability of Pasteurized Process Cheese Made with Different Types of Emulsifying Salts

ABSTRACT: Functional properties of pasteurized process cheese (PPC) made with different types of emulsifying salts (ES) (2%, wt/wt) were investigated as a function of different pH values (from 5.3 to approximately 5.9). The ES investigated were trisodium citrate (TSC), disodium phosphate (DSP), sodium hexametaphosphate (SHMP), and tetrasodium pyrophosphate (TSPP). Meltability and textural properties were determined using UW‐MeltProfiler and uniaxial compression, respectively. All PPC samples exhibited an increase in degree of flow (DOF) determined at 45 °C when the pH was increased from 5.3 to 5.6, presumably reflecting greater Ca binding by the ES, increased charge repulsion and therefore greater casein dispersion. When the pH of PPC was increased from 5.6 to approximately 5.9, 2 types of ES (DSP and SHMP) exhibited no further increase in DOF at 45 °C; while DOF increased in 1 type of PPC (made with TSC) but decreased in another (made with TSPP). TSPP is able to form crosslinks with casein especially in the vicinity of pH 6, which likely restricted melt; in contrast TSC does not crosslink caseins and the increase in pH helped cause greater casein dispersion. Low pH samples (5.3) were not significantly harder than higher pH samples for all ES types but exhibited fracture. The PPC with the highest hardness values at pHs 5.3 and 5.6 were made with TSPP and TSC, respectively. The pH‐dependent functional behavior of PPC was strongly influenced by the type of ES and its physicochemical properties including its ability to bind Ca, the possible creation of crosslinks with casein and casein dispersion during cooking.     

Casein Peptization, Functional Properties, and Sensory Acceptance of Processed Cheese Spreads Made with Different Emulsifying Salts

ABSTRACT:  " Requeijão cremoso " is a traditional Brazilian processed cheese spread, showing ample acceptance on the national market. Emulsifying salts (ES) are an important factor influencing the characteristics of processed cheeses, but the literature presents conflicting results about their action on cheese functionality.  Requeijão cremoso  obtained from anhydrous ingredients allows the study of the influence of each type of ES on the cheese properties, since it can be treated as a model system where the variables are limited and well known. The objective of this study was to evaluate the effect of different types of ES (TSC—sodium citrate, SHMP—sodium hexametaphosphate, STPP—sodium tripolyphosphate, and TSPP—tetrasodium pyrophosphate) on the sensory and functional characteristics of  requeijão cremoso -processed cheeses obtained from anhydrous ingredients. The physicochemical composition, degree of casein dissociation, fat particle size, melting index, color, texture profile, and sensory acceptance of the cheeses were determined. The functional behavior of processed cheeses was strongly influenced by the type of ES and its physicochemical properties including its ability to bind Ca, the casein dispersion during cooking, and the possible creation of cross-links with casein during cooling. The cheese made with SHMP was the one most differentiated from the others, presenting lower melting index, whiter color, and higher values for hardness, gumminess, and adhesiveness. The differences in texture had an impact on sensory acceptance: with the exception of the sample manufactured with sodium hexametaphosphate, all the samples presented good sensory acceptance.     

Modeling Rheological Characteristics and Calcium Content of Mozzarella Cheese

ABSTRACT: Correlation and regression analyses of calcium concentration and rheological characteristics in Mozzarella cheese were studied. Part-skim and fat-free Mozzarella cheeses were manufactured on 4 separate occasions. Calcium concentration in both types of cheeses was manipulated at 4 different levels. Rheological characteristics such as melt area, softening, melting, and flow were studied on days 1, 7, 15, and 30. The results revealed that 57%, 52%, 66%, 74%, 67%, and 53% variation, respectively, in melt area, softening temperature, softening time, melting time, flow rate, and extent of flow could be explained as a function of calcium concentration of part-skim Mozzarella cheese. Calcium concentration explained 50%, 61%, and 43% variation, respectively, in melting time, flow rate and extent of flow, but poor correlation existed between calcium concentration and melt area, softening and melting time-temperatures of fat-free Mozzarella cheese. Calcium concentration, among all compositional parameters, was highly correlated with rheological characteristics of Mozzarella cheeses. Calcium concentration was also one of the major predictor variables in regression models, which were developed to decide the rheological characteristics of Mozzarella cheese. Based on the above correlation the cheese industry can develop a strategy to obtain specific characteristics in Mozzarella cheese for varied applications in the food systems.     

酪蛋白酸钠美拉德反应产物的制备及其乳化特性

利用小型超高温设备制备酪蛋白酸钠与葡萄糖、乳糖、低聚半乳糖、聚葡萄糖的美拉德反应产物,对比分析不同分子质量糖在不同热处理时间的美拉德反应进程及产物的乳化特性。结果表明,小分子质量的糖更易发生美拉德反应,褐变指数与反应程度呈正相关,乳化活性与接枝度均呈现先增大后减小的趋势,但两者并不成线性关系,酪蛋白酸钠与葡萄糖、乳糖、低聚半乳糖、聚葡萄糖乳化活性达到的最大值分别为0.63、0.51、0.55和0.48,其中130?℃热处理15?s的酪蛋白酸钠-葡萄糖溶液乳化活性最大,高于其他组,与水浴90?℃热处理90?min相当,并且乳化稳定性也呈现较高的水平,为123.88?min,将其用作乳化剂制备的DHA藻油乳状液稳定性动力学指数为1.5,显著小于其他组（P＜0.05）;由此可见,葡萄糖可作为美拉德反应的优良糖基配体制备新型高效的乳化剂,并且此方法可实现连续化生产,极大缩短了反应时间,提高了生产效率,对工业化生产具有指导意义。     

乳化温度对融化干酪品质的影响

研究了乳化温度对融化干酪的品质的影响。通过对融化干酪质构分析、微观结构和感官评价测定,比较了60、65、70、75、80℃五个水平温度对融化干酪品质的影响。试验结果表明,乳化温度70℃时,融化干酪具有较高的恢复性、黏聚性、黏着性和弹性,最低的硬度、咀嚼性、胶着性;融化干酪中的酪蛋白和脂肪球相对较小,分布比较均匀,新的蛋白质网络结构形成,整个体系处于一个较好的乳化状态;融化干酪的硬度适中、组织状态光滑无颗粒、口感风味良好、切片性较好。     

大豆-坚果奶酪类似物的制备及其性质研究

该研究采用大豆乳、腰果乳及巴旦木蛋白为原料制备一种奶酪类似物,目的是确定最佳工艺配方以制备出高品质的大豆-坚果奶酪类似物,然后评价其理化性质、感官特性、储藏稳定性和消化特性。研究结果显示：具有最佳品质的大豆-坚果奶酪类似物基本配方为（皆为质量分数）：腰果乳50.00%,大豆乳50.00%;并以植物乳质量为基准,依次添加植物油3.09%（椰子油与葵花籽油比例为7:3）、巴旦木蛋白2.01%、TG酶0.33%、柠檬酸0.10%、乳酸0.10%;以凝乳质量为基准,添加胶体1.08%、蔗糖4.00%。大豆-坚果奶酪类似物硬度值0.88 N、整体感官评分7.71分,可以与商品化动物奶酪相媲美。此外,随着储藏时间增加其硬度值从0.94 N增加到1.15 N,无明显变硬和析水现象。体外消化结果显示其蛋白电泳条带在肠道消化180 min后全部消失,游离脂肪酸释放速率为60%。因此,制备的大豆- 坚果奶酪类似物营养价值高,具有较佳的感官品质,储藏稳定性好且蛋白易于消化,能够作为动物奶酪的替代物以满足人们对奶酪的需求。     

酪蛋白酸钠膜的水分吸附特性

作者以大豆蛋白酪蛋白酸钠(NaCas)膜为对象,从吸附动力学和水分吸附等温线研究了蛋白膜的水分吸附特性.NaCas膜水分达到平衡所需要的时间受到所处相对湿度(RH)条件和增塑剂含量的影响.RH和增塑剂含量越低,达到平衡的时间越短;反之,则越长.TGase改性明显降低了蛋白膜的水分吸附速率及达到平衡的水分含量.NaCas膜水分吸附等温线数据能很好地与GAB模型吻合.     

Calcium Supplementation of Cottage Cheese

Cottage cheese (100 g) provides only 6% of the calcium Recommended Daily Allowance for adults. Samples of fresh cheese were supplemented with calcium salts (chloride, lactate, or phosphate monobasic) to double the calcium content of the cheese to approximately 145 mg/100 g, and the effects of the supplementation on taste and microbial stability were studied. Supplementations did not affect pH or microbial stability during 21 d of refrigerated storage. Sensory evaluation results of a 12-member taste panel showed higher flavor and preference scores for control than for all supplemented samples (P<.05) but no difference in odor, color, or texture. Overall, chloride appeared to be preferable for calcium content supplementation because only .26% (wt/wt) of the salt was required to obtain the desired calcium content level and the mineral was evenly distributed in the cheese.     

奶渣酪蛋白酸钙的制备及在植脂末中的应用

以奶渣酪蛋白为原料,制备的酪蛋白酸钙中钙含量为指标,采用单因素试验,确定奶渣酪蛋白酸钙的生产工艺,对奶渣酪蛋白酸钙的理化性质进行测定,以奶渣酪蛋白酸钙作为乳化剂制备植脂末,并与奶渣酪蛋白酸钠及市售酪蛋白酸钙制备的植脂末进行对比,通过测定其粒径和ζ-电位探究植脂末的稳定性。结果表明：溶液pH值为7,料液浓度为1.00%,Ca(OH)2添加量为1.6%时,奶渣酪蛋白酸钙中蛋白质含量为93.76%,钙含量为1.35%;奶渣酪蛋白酸钙具有优异的乳化能力,乳化液稳定性可达到70%以上,起泡能力高于奶渣酪蛋白酸钠;由奶渣酪蛋白酸钙制备的植脂末平均粒径最小,电位绝对值最大,稳定性最好,并且随储藏时间的延长,粒径和ζ-电位变化最小,储藏稳定性最好。     

Improved Complexometric Determination of Calcium in Cheese

Accuracy and repeatability of complexometric methods for measuring calcium in cheese are limited by titration endpoints that are difficult to recognize. Much of this difficulty results from turbidity during titration. An alternative procedure is described in which 2 to 3 g of cheese are ashed, dissolved in dilute acid, and added calcium chloride is back titrated with ethylenediaminetetraacetic acid using hydroxy naphthol blue as indicator. Samples remain free of turbidity, and the titration endpoint is recognized easily.Recovery of calcium from solutions containing magnesium and phosphate was 100.9 ± .3%, indicating that a portion of sample magnesium (about 12%) also was measured. Error caused by magnesium recovery represented less than 1% of true calcium content.Analyses of 10 Cheddar cheese samples by the proposed method and by atomic emission differed by an average of .010% calcium. Mean values of the 10 samples did not differ significantly (P>.05) between methods. Duplicate analyses of 67 Cheddar cheese samples differed by an average of .008 ± .006% calcium. Similar repeatability was achieved by several inexperienced analysts. The method is applied readily to other dairy products.     

鹰嘴豆全粉的乳化特性

为探究鹰嘴豆全粉的乳化特性及影响其乳化特性的因素,实现鹰嘴豆的高效应用,以鹰嘴豆全粉为原料,探究全粉溶液浓度、油相体积分数及过筛目数对鹰嘴豆乳液乳化特性的影响。通过测定粒径、电位、乳化特性、乳液总体稳定指数(turbiscan stability index,TSI)等指标对全粉乳液进行表征。结果表明:全粉溶液浓度为40 mg/mL时,乳液的粒径最小且电位的绝对值最大;油相体积分数为10%时,乳液的粒径最小,为(8.05±0.22)μm,乳化活性指数及乳化稳定性指数最高,分别为(23.63±0.32)m²/g、(63.26±0.26)min;相较于以上两种变量条件,目数对于乳液的乳化特性影响较小。综上,鹰嘴豆全粉过120目筛、浓度为40 mg/mL、油相体积分数为10%时,乳液具有较好的乳化特性。该结果可为简化食品生产工艺、促进鹰嘴豆全粉作为乳化剂的开发应用奠定理论基础。     

Effect of Calcium on Physicochemical Properties of Fat-free Mozzarella Cheese

ABSTRACT: Fat-free mozzarella cheeses containing 4 levels of calcium (0.79%, 0.66%, 0.59%, and 0.50%) were manufactured on 4 separate occasions. Meltability as softening time and temperature, melting time and temperature, flow rate, extent of flow, decrease in cheese height during melting, melt area, whiteness ( L * value) at 5 and 60 °C and proteolysis were evaluated on 1, 7, 15, and 30 d. Reduction of 35% of the calcium increased the cheese flow to 2.5 times and the cheese also required 19% less time to melt. Low-calcium fat-free cheeses required lower temperature and less time to soften and melt, and had greater and faster flow. Whiteness decreased and proteolysis was greater in low-calcium cheeses.     

Texture and Microstructure of Block Type Processed Cheese with Formulated Emulsifying Salt Mixtures

Block-processed Ras cheese was produced with two salt mixtures: (1) Na-diphosphate+Na-polyphosphate+Na-tripolyphosphate in ratios 40 : 50 : 10, 30 : 40 : 30 & 30 : 30 : 40 and (2) Na-polyphosphate+Na-citrate+Na-orthophosphate+Na-diphosphate in ratios 50 : 20 : 20 : 10, 40 : 10 : 20 : 30 & 30 : 10 : 20 : 40. Commercial salts Joha SE and PZO were used for comparison, respectively. Texture profile analysis and microstructure (LM and TEM) of resultant cheeses were studied. Chewiness, gumminess, adhesiveness, and hardness showed a significant difference and the cheese samples exhibited higher values during storage. The values were highest in the samples stored at room temperature. Light microscopy photographs indicated different emulsification degree with various emulsifying salt mixtures. These observations were confirmed with the image analysis and TEM. Among the entire treatments, mixture (1) in ratio 30 : 40 : 30 and mixture (2) in ratio 40 : 10 : 20 : 30 gave the best and close texture to the commercial salts and can be recommended in the production of block processed cheese.