Emulsifying Salts Research Articles

The effect of age on Cheddar cheese melting, rheology and structure, and on the stability of feed for cheese powder manufacture

Age-related changes to the rheology and structure of Cheddar for cheese powder manufacture, and how this influences the stability of cheese feed during pre-spray-drying storage, were investigated. Cheddar cheese (3, 5, 7, 9, 12 and 15 months old) was analysed for meltability by the Schreiber Test and small angle oscillation measurements. Results showed increasing stiffness and reduced activation energy for initiation of milk fat melting with age. Cheese feeds for manufacture of cheese powder were made, with or without emulsifying salts (ES), and analysed for emulsion stability. In the absence of ES, feeds made from 3 month old Cheddar were significantly more stable than those made from 5 month old cheese. A similar significant increase in emulsion stability was observed for cheeses of 7 months of age compared with 12 months, indicating the necessity to use Cheddar cheese aged 3 months or less to produce stable cheese feeds without ES.

Potential and restrictions of photocentrifugation for determining the emulsion stability of melted spreadable processed cheese

A previous study had shown that the method of photocentrifugation could be adapted to monitor emulsion stability of melted spreadable processed cheese (PC) with low content of emulsifying salts (ES). The present study continued the experiments with higher ES content exploring the potential and restrictions of this new approach. The PC containing 40% fat in dry matter and 1.0 or 1.9% w/w ES was manufactured for 5–19 min at 82 °C and three different rotational speeds of the cutter. Light transmission was measured during centrifugation of the melted PC in thin cuvettes at 60 °C. The transmission profiles were used to characterize emulsion stability. Fat distribution was measured for better interpretation of the centrifugation results. An increase in transmission to ≥20% occurred after different periods of centrifugation at 1200×g. Samples with 1.0% w/w ES showed different particle movements during centrifugation for 150 min. Polydisperse creaming, sedimentation, and distinct zone sedimentation were identified, the latter allowing the calculation of characteristic sedimentation velocities. The PC with 1.9% w/w ES manufactured at a cutter speed of 3000 rpm for 5 min required the maximum acceleration of 2150×g to achieve measurable transmission after 195 min, corresponding to 291 days under normal gravity. These results show the high sensitivity of photocentrifugation proving even little physical changes of the PC matrix. However, this sensitivity restricts the applications to melted spreadable and suboptimal emulsified products.

Evaluation of X-ray fluorescence spectroscopy as a method for the rapid and direct determination of sodium in cheese

Cheese manufacturers indirectly determine Na in cheese by analysis of Cl using the Volhard method, assuming that all Cl came from NaCl. This method overestimates the actual Na content in cheeses when Na replacers (e.g., KCl) are used. A direct and rapid method for Na detection is needed. X-ray fluorescence spectroscopy (XRF), a mineral analysis technique used in the mining industry, was investigated as an alternative method of Na detection in cheese. An XRF method for the detection of Na in cheese was developed and compared with inductively coupled plasma optical emission spectroscopy (ICP-OES; the reference method for Na in cheese) and Cl analyzer. Sodium quantification was performed by multi-point calibration with cheese standards spiked with NaCl ranging from 0 to 4% Na (wt/wt). The Na concentration of each of the cheese standards (discs: 30mm×7mm) was quantified by the 3 methods. A single laboratory method validation was performed; linearity, precision, limit of detection, and limit of quantification were determined. An additional calibration graph was created using cheese standards made from natural or process cheeses manufactured with different ratios of Na:K. Both Na and K calibration curves were linear for the cheese standards. Sodium was quantified in a variety of commercial cheese samples. The Na data obtained by XRF were in agreement with those from ICP-OES and Cl analyzer for most commercial natural cheeses. The XRF method did not accurately determine Na concentration for several process cheese samples, compared with ICP-OES, likely due to the use of unknown types of Na-based emulsifying salts (ES). When a calibration curve was created for process cheese with the specific types of ES used for this cheese, Na content was successfully predicted in the samples. For natural cheeses, the limit of detection and limit of quantification for Na that can be determined with an acceptable level of repeatability, precision, and trueness was 82 and 246mg/100g of cheese, respectively. Calibration graphs should be created with standards that reflect the concentration range, ratio, and salt type present in the cheeses. This XRF method can be successfully used for the rapid and direct measurement of Na content in a wide variety of natural cheeses. Commercial process cheese manufacturers use proprietary blends of ES. We did find that the XRF technique worked for process cheese when the calibration graphs were created with the specific types of ES actually used.

Dispersion analysis of spreadable processed cheese with low content of emulsifying salts by photocentrifugation

SummaryPhotocentrifugation at 1200 g and 60 °C was used to monitor emulsion stability of spreadable processed cheese (PC) with a low content (0.7 and 1.0 g 100 g−1) of typical emulsifying salts (ES) after different manufacturing conditions. This method of dispersion analysis has been used more frequently for nonfood materials rather than for foodstuffs. The PC contained 36.5 g 100 g−1 dry matter, 40 g 100 g−1 fat in dry matter and was manufactured in a laboratory cooker at 82 or 92 °C and 1000–3000 rpm cutter speed for 5–19 min. Insufficient fat emulsification and a heterogeneous casein matrix of a PC with 0.7% was well illustrated by photocentrifugation. At 1 g 100 g−1 ES and 3000 rpm cutter speed, the effect of manufacturing time on the behaviour of the colloidal dispersion was demonstrated by the different evolutions of the corresponding transmission profiles. Sedimentation velocities were measured at a level of 20% transmission. These results showed that dispersion analysis of spreadable PC by photocentrifugation at 60 °C is a sensitive method and applicable as a new approach for characterisation of emulsion stability resulting from physicochemical changes during manufacture.

Effect of potassium-based emulsifying salts on sensory, textural, and functional attributes of low-sodium processed Mozzarella cheese

Dietary sodium content is considered as a major contributor to hypertension and cardiovascular diseases. Mozzarella cheese contains high amount of sodium, and addition of emulsifying salts (ESs) to the manufacture of processed cheese further adds to the overall sodium content. The present investigation envisaged the manufacture of low-sodium processed Mozzarella cheese by partial replacement of sodium chloride with potassium chloride (KCl) and also by using potassium-based emulsifying salts, i.e., potassium citrate and di-potassium phosphate, in place of sodium-containing salts. Desired level of potassium chloride and potassium-based emulsifying salt was optimized using response surface methodology (RSM). Sensory attributes, instrumental hardness, meltability, and stretchability were kept as responses of the design. The study returned 30.96% of KCl and 2% of emulsifying salt to be optimum, and at these levels, the product had maximum sensory scores. Hardness, meltability, and stretchability of the product were reported to be 14.355 N, 21.68 cm and 15.07 cm, respectively. Further, the study was validated by manufacturing the product using optimized levels of ESs and KCl and comparing the actual responses with the responses predicted by RSM. No significant difference (p > 0.05) between actual and predicted values validated the results of RSM. Full-sodium and low-sodium cheeses had 905 mg/100 g and 260 mg/100 g sodium, respectively. Thus, the study resulted in 71.27% reduction in overall sodium content of processed Mozzarella cheese.

Effect of increasing the protein-to-fat ratio and reducing fat content on the chemical and physical properties of processed cheese product

Scientific studies indicate that the intake of dietary fat and saturated fats in the modern Western diet is excessive and contributes adversely to health, lifestyle, and longevity. In response, manufacturers of cheese and processed cheese products (PCP) are pursuing the development of products with reduced fat contents. The present study investigated the effect of altering the fat level (13.8, 18.2, 22.7, 27.9, and 32.5g/100g) in PCP on their chemical and physical properties. The PCP were formulated in triplicate to different fat levels using Cheddar cheese, skim milk cheese, anhydrous milk fat, emulsifying salt (ES), NaCl, and water. The formulations were designed to give fixed moisture (~53g/100g) and ES:protein ratio (0.105). The resultant PCP, and their water-soluble extracts (WSE), prepared from a macerated blend of PCP and water at a weight ratio of 1:2, were analyzed at 4d. Reducing the fat content significantly increased the firmness of the unheated PCP and reduced the flowability and maximum loss tangent (fluidity) of the melted PCP. These changes coincided with increases in the levels of total protein, water-soluble protein, water-insoluble protein, and water-soluble Ca, and a decrease in the molar ratio of water-soluble Ca to soluble P. However, both water-soluble Ca and water-soluble protein decreased when expressed as percentages of total protein and total Ca, respectively, in the PCP. The high level of protein was a major factor contributing to the deterioration in physical properties as the fat content of PCP was reduced. Diluting the protein content or reducing the potential of the protein to aggregate, and thereby form structures that contribute to rigidity, may provide a means for improving quality of reduced-fat PCP by using natural cheese with lower intact casein content and lower calcium:casein ratio, for example, or by decreasing the ratio of sodium phosphate to sodium citrate-based ES.

Effect of chelating salt type on casein hydration and fat emulsification during manufacture and post-manufacture functionality of imitation cheese

Imitation cheese (50% moisture) was manufactured in a Farinograph using different ratios of disodium orthophosphate (DSP) and trisodium citrate (TSC) as chelating or emulsifying salts (ES). The ES:casein ratio was kept constant at 0.2549 mol ES/kg casein. The effects of DSP:TSC ratio on cheese manufacture and post-manufacture functional properties were investigated. Hardness, assessed by texture profile analysis, heat-induced flowability and dynamic rheology were studied. Microstructural analyses were performed using light and cryo-scanning electron microscopy. Increasing the DSP:TSC ratio from 0:1 to 1:0 caused a decrease in processing times (from ∼18 to 12 min) and lowering of the final mixing torque values (from ∼180 to 20 F.U.) and, post-manufacture led to a decrease in cheese hardness (from ∼360 to 165 N) and G′ values at 25 °C (from ∼81 to 38 kPa) and to increased cheese fat globule size (from ∼8 to 32 μm). The results suggest that changing the ratio of DSP:TSC may be used to alter cheese properties, but both ES are needed for optimum functionality.

Effect of sodium hexametaphosphate concentration and cooking time on the physicochemical properties of pasteurized process cheese

Sodium hexametaphosphate (SHMP) is commonly used as an emulsifying salt (ES) in process cheese, although rarely as the sole ES. It appears that no published studies exist on the effect of SHMP concentration on the properties of process cheese when pH is kept constant; pH is well known to affect process cheese functionality. The detailed interactions between the added phosphate, casein (CN), and indigenous Ca phosphate are poorly understood. We studied the effect of the concentration of SHMP (0.25–2.75%) and holding time (0–20min) on the textural and rheological properties of pasteurized process Cheddar cheese using a central composite rotatable design. All cheeses were adjusted to pH 5.6. The meltability of process cheese (as indicated by the decrease in loss tangent parameter from small amplitude oscillatory rheology, degree of flow, and melt area from the Schreiber test) decreased with an increase in the concentration of SHMP. Holding time also led to a slight reduction in meltability. Hardness of process cheese increased as the concentration of SHMP increased. Acid-base titration curves indicated that the buffering peak at pH 4.8, which is attributable to residual colloidal Ca phosphate, was shifted to lower pH values with increasing concentration of SHMP. The insoluble Ca and total and insoluble P contents increased as concentration of SHMP increased. The proportion of insoluble P as a percentage of total (indigenous and added) P decreased with an increase in ES concentration because of some of the (added) SHMP formed soluble salts. The results of this study suggest that SHMP chelated the residual colloidal Ca phosphate content and dispersed CN; the newly formed Ca-phosphate complex remained trapped within the process cheese matrix, probably by cross-linking CN. Increasing the concentration of SHMP helped to improve fat emulsification and CN dispersion during cooking, both of which probably helped to reinforce the structure of process cheese.

Effects of emulsifying salts reduction on imitation cheese manufacture and functional properties

Imitation cheese (48%, 50% and 52% moisture) was manufactured using a Farinograph. The standard emulsifying salts (ES) concentration was 1.4%, giving a casein:ES ratio of 19:12. The effect of ES reduction on cheese manufacture and functionality, assessed by texture profile analysis, heat-induced flowability and dynamic rheology, was studied. Microstructure was investigated by light and cryo-scanning electron microscopy. Reducing ES increased processing time and hardness and decreased flowability and fat globule diameter. In comparison to standard ES, a reduction of up to 20% produced cheeses in reasonable processing times with slightly altered functionality. On further ES reduction, processing times greatly increased giving much harder and less meltable cheeses. Reducing ES by 40% increased processing times ∼3-fold, halved fat globule diameter and flowability and doubled hardness, compared to standard cheeses. At ES reduction above 40% the product obtained, after prolonged processing time, bore little resemblance to cheese.

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

"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.

Meltability and Stretchability of White Brined Cheese: Effect of Emulsifier Salts

Problem statement: This study was based on the hypothesis that by addi ng low concentrations of emulsifier salts, may specificall y act on the cross linking bonds of the protein mat rix, to the original brine (storage medium) it would be possible to induce meltability and stretchability i n white brined cheese. Approach: A new apparatus for measuring the actual stretchab ility was designed and constructed; measurements on different cheese s amples proved its validity and reliability to measure stretchability. The apparatus was used to e valuate the effect of five types of emulsifier salt s under different processing conditions. Results: It was found that by adding 0.2% (w/w) Puromelt C1 or Monosodium phosphate to the brine of white brined cheese, higher levels of stretchability and meltability were induced after 2-4 weeks of storage . Conclusion: Addition of emulsifying salts was proved to be effective method in inducing meltabili ty and stretchability of white brined cheese. Type of salt, its concentration, type of cheese and soak ing time are factors that should be controlled to a ttain the optimum results.

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

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 degrees 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 degrees 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.

Influence of Emulsifying Salts on the Textural Properties of Nonfat Process Cheese Made from Direct Acid Cheese Bases

The objective of this study was to investigate the influence of several types of emulsifying salts (ES) on the texture of nonfat process cheese (NFPC). Improperly produced nonfat cheese tends to exhibit several problems upon baking including stickiness, insufficient or excessive melt, pale color upon cooling, formation of a dry skin (skinning) often leading to dark blistering, and chewy texture. These attributes are due to the strength and number of interactions between and among casein molecules. We propose to disrupt these interactions by using suitable emulsifying salts (ES). These ES chelate Ca and disperse caseins. Stirred curd cheese bases were made from skim milk using direct acidification with lactic acid to pH values 5.0, 5.2, and 5.4, and ripened for 1 d. Various levels of trisodium citrate (TSC; 0.5, 1, 1.5, 2, 2.5, 3, and 5%), disodium phosphate (DSP; 1, 2, 3, and 4%), or trisodium phosphate (TSP; 1, 2, 3, and 4%) were blended with the nonfat cheese base. Cheese, ES, and water were weighed into a steel container, which was placed in a waterbath at 98°C and then stirred using an overhead stirrer for 9min. Molten cheese was poured into plastic containers, sealed, and stored at 4°C for 7 d before analysis. Texture and melting properties were determined using texture profile analysis and the UW-Melt-profiler. The pH 5.2 and 5.4 cheese bases were sticky during manufacture and had a pale straw-like color, whereas the pH 5.0 curd was white. Total calcium contents were approximately 400, 185, and 139mg/100g for pH 5.4, 5.2, and 5.0 cheeses, respectively. Addition of DSP resulted in NFPC with the lowest extent of flow, and crystal formation was apparent at DSP levels above 2%. The NFPC manufactured from the pH 5.0 base and using TSP had reduced melt and increased stickiness, whereas melt was significantly increased and stickiness was reduced in NFPC made with pH 5.4 base and TSP. However, for NFPC made from the pH 5.4 cheese and with 1% TSP, the pH value was >6.20 and crystals were observed within a few days. Use of TSC increased extent of flow up to a maximum with the addition of 2% ES for all 3 types of cheese bases. Addition of high levels of TSC to the pH 5.2 and 5.4 cheese bases resulted in increased stickiness. Similar pH trends for attributes such as extent of flow, hardness, and adhesiveness were observed for both phosphate ES but no consistent pH trends were observed for the NFPC made with TSC. These initial trials suggest that the pH 5.0 cheese base was promising for further research and scale-up to pilot-scale process cheese making, because cheeses had a creamy color, reasonable melt, and did not have high adhesiveness when TSC was used as the ES. However, the acid whey produced from the pH 5.0 curd could be a concern.

Effects of Two Types of Emulsifying Salts on the Functionality of Nonfat Pasta Filata Cheese

Effects of 2 types of emulsifying salts (ES) on the functionality of nonfat pasta filata cheese were examined. Nonfat pasta filata cheese was made from skim milk by direct acidification. Trisodium citrate (TSC) and tetrasodium pyrophosphate (TSPP) were added to curds (at 1, 3, and 5%, wt/wt) at the dry-salting step, together with glucono-δ-lactone to maintain a constant pH. When TSC was added, there were no significant compositional differences, although insoluble Ca and P contents significantly decreased with the addition of TSC. When TSPP was added, fat content was not significantly different, but protein content decreased with increasing concentrations of TSPP. Both insoluble Ca and P contents increased with the addition of 1% TSPP. The addition of ES affected textural and functional properties. With increasing concentrations of TSC, meltability increased, whereas increasing the TSPP content decreased meltability. Cheese made with 1% TSC had better stretchability compared with control cheese. However, the addition of more than 3% TSC decreased stretchability. Addition of TSPP caused a considerable decrease in stretchabilty. Scanning electron microscopy revealed that the size and number of serum pockets decreased and protein appeared more hydrated with the addition of both ES. These results suggested that TSC and TSPP influenced the functionality of nonfat pasta filata cheese differently; that is, the effects of TSC were probably caused by a decrease in the number of colloidal calcium phosphate cross-links and an increase in electrostatic repulsion, whereas the effects of TSPP may have been related to the formation of new TSPP-induced casein-casein interactions.

Effects of Emulsifying Salts on the Turbidity and Calcium-Phosphate–Protein Interactions in Casein Micelles

Influence of emulsifying salts (ES) on some physical properties of casein micelles was investigated. A reconstituted milk protein concentrate (MPC) solution (5% wt/wt) was used as the protein source and the effects of ES [0 to 2.0% (wt/wt)] were estimated by measuring turbidity, acid-base titration curves and amount of casein-bound Ca and inorganic P (Pi). Various ES, trisodium citrate (TSC), or sodium phosphates (ortho-, pyro-, or hexameta-) were added to MPC solution, and all samples were adjusted to pH 5.8. Acid-base buffering curves were used to observe changes in the amount and type of insoluble Ca phosphates. An increase in the concentration of TSC added to MPC solution decreased turbidity, buffering at pH ∼5 (contributed by colloidal Ca phosphate), and amount of casein-bound Ca and Pi. Addition of up to 0.7% disodium orthophosphate (DSP) did not significantly influence turbidity, buffering curves, or amount of casein-bound Ca and Pi. When higher concentrations (i.e., ≥1.0%) of DSP were added, there was a slow decrease in turbidity. With increasing concentration of added tetrasodium pyrophosphate (TSPP), turbidity and buffering at pH ∼5 decreased, and amount of casein-bound Ca and Pi increased. When small concentrations (i.e., 0.1%) of sodium hexameta-phosphate were added, effects were similar to those when TSPP were added but when higher concentrations (i.e., ≥0.5%) were added, the buffering peak shifted to a higher pH value, and amount of casein-bound Ca and Pi decreased. These results suggested that each type of ES influenced casein micelles by different mechanisms.

Physical and Sensory Properties of Block Processed Cheese with Formulated Emulsifying Salt Mixtures

Various emulsifying salt mixtures were used in making block type processed cheeses. Ras cheese was used as the cheese base with two salt mixtures: (i) Na-diphosphate + Na-polyphosphate + Na-tripolyphosphate and (ii) Na-poly-phosphate + Na-citrate + Na-orthophosphate + Na-diphosphate comparing to commercial salts Joha SE and PZO respectively. The resultant processed cheeses were analyzed when fresh and monthly during storage at 7 and 20°C for water activity (a w ), oil separation, meltability, flow behavior, color parameters, and sensory properties. There were no significant differences in water activity values among all treatments. The differences were significant in oil index and meltability values. The samples exhibited different shear stress values and it was highest in treatments with commercial salts. Consistency coefficient (k-value) of processed cheese samples was affected by emulsifying salt mixture being almost two folds higher with salt mixtures (i) than those of salt mixtures (ii). The color parameters L, a, b, Chroma and hue angle showed slight differences among treatments and the cheese was shinier and whiter with increasing pyrophosphate content in the salt mixture. The stored samples became less white especially when stored at room temperature (20°C). Sensory evaluation showed that all cheeses were acceptable but the most acceptable samples were produced with mixtures in the ratio of (i) 30:40:30 and (ii) 50:20:20:10.

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.

EFFECT OF EMULSIFYING SALTS ON OBJECTIVE AND SUBJECTIVE PROPERTIES OF PROCESSED CHEESE

ABSTRACTThe effects of several types of emulsifying salts (ES) currently used in the manufacture of processed cheese were evaluated with particular emphasis on water‐soluble nitrogen (WSN), relative casein content (RCC), and general acceptability. For the ES at the 3% level, no significant differences were obtained for RCC and general acceptability, with significant differences (P > 0.05) obtained for WSN. For the ES at high and low levels, no significant differences were obtained for WSN and general acceptability, while significant differences (P > 0.05) were obtained for RCC.

Spectrophotometric determination of hydrogen-ion concentrations and of the apparent dissociation constants of indicators. IV. I-naphthol-2-sodium sulphonate indophenol

Pasteurized processed cheese products (PCPs) are cheese-based foods prepared by blending one or more natural cheeses, water, emulsifying salts (ESs), and optional ingredients, and heating the blend to temperatures of ∼75–85 °C while continuously shearing until a smooth, uniform molten mass is obtained. The hot molten product is filled moulded into a large variety of shapes and sizes suited to end user requirements, cooled, and stored at ∼8 °C. There are various types of PCPs (e.g., processed cheese, cheese spread, and cheese foods) defined by national legislation. Such legislation defines the composition, natural cheese content (ranging from 51 to about 96% of the final dry matter), and permitted ingredients for the different types. Optional ingredients may include dairy ingredients, condiments, flavors, colors, and preservatives. ESs such as sodium phosphates and citrates, while not emulsifiers per se, are central to the formation of stable PCPs. They mediate the demineralization of the insoluble cheese protein and its conversion to a functional protein that binds water and emulsifies free fat released during processing. The properties of PCPs, such as flavor, texture, and cooking attributes, are determined by many factors including the age/type of natural cheese, characteristics of ingredients, pH, and processing conditions.