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Factors affecting functionality of Mozzarella cheese
... De multiples techniques ont été proposées pour apprécier les propriétés fonctionnelles à chaud des fromages [14,23,26,28]. La mesure des propriétés de fonte et d'étalement, qualités principalement étudiées, fait souvent appel à des tests de type empirique, simulant le comportement du fromage en conditions culinaires : tests de Schreiber [19,22], d'Arnott [26], du tube [28], de perte de forme [6], détermination du point de ramollissement [5,21,28]. ...
... De multiples techniques ont été proposées pour apprécier les propriétés fonctionnelles à chaud des fromages [14,23,26,28]. La mesure des propriétés de fonte et d'étalement, qualités principalement étudiées, fait souvent appel à des tests de type empirique, simulant le comportement du fromage en conditions culinaires : tests de Schreiber [19,22], d'Arnott [26], du tube [28], de perte de forme [6], détermination du point de ramollissement [5,21,28]. L'évaluation sensorielle est parfois utilisée [2,18]. ...
... L'évaluation sensorielle est parfois utilisée [2,18]. Des méthodes plus fondamentales, non directement reliées à la perception du consommateur, ont également été proposées [2,14,20,23,26,31] : essais harmoniques sous balayage de température, viscosité élongationelle bi-axiale apparente, rhéométrie capillaire. ...
Quatre techniques de mesure des propriétés fonctionnelles de l’Emmental ont été développéesou adaptées pour la détermination des caractéristiques d’étalement, de filant, d’exsudationd’huile et de couleur de gratin. L’étalement était mesuré par un test de Schreiber modifié, la couleurde gratin par une analyse au chromamètre (L*, a*, b*). Des méthodes originales ont été développéespour l’appréciation du filant (test de traction verticale) et de l’exsudation d’huile (méthode butyrométrique).La répétabilité et le pouvoir discriminant de ces analyses ont été déterminés. Quarante-huitéchantillons d’Emmentals du commerce, représentatifs de la production française, ont été prélevés etcaractérisés. Le coefficient d’étalement (rapport des surfaces du fromage fondu et du fromage initial)variait de 1 à 2,7. L’exsudation d’huile variait de 7 à 17 g de matière grasse pour 100 g de fromage soit30 à 60 g.100 g–1 de matière grasse. La longueur des fils de fromage fondu variait entre 80 et 950 mm.Pour la couleur des gratins, des plages de variation de 13 unités arbitraires (u.a.) de L*, 9 u.a. de a* et9 u.a. de b* ont été enregistrées. L’intensité du brunissement, de l’étalement, de l’exsudation d’huileet du filant étaient fortement corrélés. Une analyse en composantes principales a révélé une grandediversité de propriétés fonctionnelles à chaud au sein de l’univers de l’Emmental français.
... De multiples techniques ont été proposées pour apprécier les propriétés fonctionnelles à chaud des fromages [14,23,26,28]. La mesure des propriétés de fonte et d'étalement, qualités principalement étudiées, fait souvent appel à des tests de type empirique, simulant le comportement du fromage en conditions culinaires : tests de Schreiber [19,22], d'Arnott [26], du tube [28], de perte de forme [6], détermination du point de ramollissement [5,21,28]. ...
... De multiples techniques ont été proposées pour apprécier les propriétés fonctionnelles à chaud des fromages [14,23,26,28]. La mesure des propriétés de fonte et d'étalement, qualités principalement étudiées, fait souvent appel à des tests de type empirique, simulant le comportement du fromage en conditions culinaires : tests de Schreiber [19,22], d'Arnott [26], du tube [28], de perte de forme [6], détermination du point de ramollissement [5,21,28]. L'évaluation sensorielle est parfois utilisée [2,18]. ...
... L'évaluation sensorielle est parfois utilisée [2,18]. Des méthodes plus fondamentales, non directement reliées à la perception du consommateur, ont également été proposées [2,14,20,23,26,31] : essais harmoniques sous balayage de température, viscosité élongationelle bi-axiale apparente, rhéométrie capillaire. ...
Four methods were developed or revised to determine the functionality of melted Emmental-cheese (Swiss-cheese). Flowability was measured using a modified Schreiber test. Stretchability was assessed by a new method involving vertical traction. A butyrometric method was applied to quantify oiling-off. Browning of cheese-gratin was measured objectively with a colour meter (L*, a*, b*). The repeatability and the power of these tests were satisfactory. The functionality of 48 french commercial Emmental-cheeses was determined over one year. Great variations were registered. The flowability index (melted cheese area divided by the initial area) ranged from 1.0 to 2.7. The oiling-off ranged from 7 to 17 g fat per 100 g of cheese (30 to 60 g·100 g-1 fat). The length of the strings of melted cheese (Stretchability) ranged from 80 to 950 mm. Ranges of 13 a.u. L*, 9 a.u. a* and 9 a.u. b* were observed for colour measurement. Meltability, stretchability, oiling-off and browning were strongly correlated. Finally, Principal Component Analysis showed the great diversity of the functionality of melted French Emmental-cheese.
... The functionality of heated Mozzarella cheese depends on several factors: meltability, stretchability, free oil formation, and browning. These properties play heavily on consumer perceptions of cheese quality (Rowney et al., 1999;; Pilcher and Kindstedt, 1990). ...
... Key functional properties of melted Mozzarella cheese, namely meltability, stretchability, free oil formation, and browning are highly dependent on the underlying cheese structure and composition. Moisture content, percentages of fat, salt, and minerals (calcium specifically) as well as pH and extent of proteolysis dictate the resultant functionality of the cheese (Yun et al., 1993a;Farkye et al., 1991;Rowney et al., 1999;Kindstedt and Guo, 1998;Metzger et al., 2001;Guinee et al., 2002). ...
... Meltability describes the degree with which cheese shreds are able to melt and flow together. Proper degree of melt can be achieved by carefully monitoring pH, calcium and phosphorus levels, and extent of agingRowney et al., 1999;Guinee et al., 2002). Fat content also plays a significant factor in meltability. ...
... The functionality of heated cheese is influenced by many factors (Guinee, 2002;Kindstedt, 1993Kindstedt, , 1995Rowney et al., 1999), including variations in: l milk pretreatments, for example, pasteurization conditions, homogenization; l make procedure, for example, set pH, cooking temperature, pH at whey drainage, plasticization conditions; l compositional parameters, for example, concentrations of fat, protein and moisture; calcium-to-casein ratio, pH, l degree of proteolysis l other factors (e.g., absence or inclusion of fat replacers or whey proteins). ...
... Cheese varieties also differ markedly with respect to change in flowability, and consequently, the level of flow after any given storage time. Differences in flowability between different cheeses can result from differences in milk pretreatments, make procedure, composition, proteolysis, and ripening conditions (Guinee, 2002;Henneberry et al., 2015;Kindstedt, 1993Kindstedt, , 1995McMahon et al., 1993a;Rowney et al., 1999) To protect the rights of the author(s) and publisher we inform you that this PDF is an uncorrected proof for internal business use only by the author(s), editor(s), reviewer(s), Elsevier and typesetter Thomson Digital. It is not allowed to publish this proof online or in print. ...
There are a total of 500 (IDF, 1981) to 800 varieties of cheese. Although most cheese is consumed as “table cheese,” which may be arbitrarily defined as cheese eaten on its own or as an accompaniment to bread or crackers during meals, significant quantities of cheese are also consumed as an ingredient in cheese-based dishes/snacks in the home, food service, and prepared consumer foods. Notable examples of natural cheeses used in these applications include Cheddar, Mozzarella, and Emmental, with typical dishes including toasted sandwiches, quiche, omelettes, pasta, pizza, and lasagne. As an ingredient, pertinent attributes or functionalities of the unheated cheese include crumbliness, sliceability, spreadability, shreddability or grateability, and those of a heated cheese include overall appearance, flavor, extent of flow, stringiness, fluidity, and oiling-off. The type and level of functionality required depends upon the application. Hence, Feta cheese which is crumbly is ideal for tossed salad; Parmesan, which grates very well into small particles, for sprinkling onto lasagne or pasta dishes; and heated Mozzarella, which exhibits moderate flow and the ability to form fibrous strings when extended, for pizza. Nevertheless, the functional attributes, and, hence, suitability of any specific cheese type as an ingredient can vary due to age and degree of maturity, slight differences in make procedure and composition (such as calcium content and pH).
... The functionality of heated cheese is influenced by many factors (Kindstedt, 1993(Kindstedt, , 1995Rowney et al., 1999;Guinee, 2002; 'Pasta-Filata Cheeses', Volume 2), including variations in: ...
... Cheese varieties also differ markedly with respect to the change in flowability with ripening time and, consequently, the level of flow after any given storage time. Differences in flowability between different cheeses can result from differences in milk pre-treatment, make procedure, composition, proteolysis and ripening conditions (Kindstedt, 1993(Kindstedt, , 1995McMahon et al., 1993a;Rowney et al., 1999;Guinee, 2002; Pasta-Filata Cheeses, Volume 2; 'Differences in protein and fat contents', 'Storage time and proteolysis', 'Degree of fat emulsification (DEE), fat coalescence and milk homogenization', 'Effect of whey proteins and casein-whey protein interaction on flowability', 'Browning of cheese as a consequence of Maillard reaction' and 'Cheese Ingredients'). The interactive effects of these factors influence the degree of protein aggregation, or hydration, and the level of fat coalescence on heating, which in turn determine the level of heat-induced displacement. ...
This chapter discusses about cheese as a highly versatile dairy ingredient that is used directly or indirectly in the form of cheese ingredients in a vast array of culinary, formulated, and prepared food products. The rheological, flavor, and cooking properties are functional attributes that have a major impact on the preparation and quality of these products. Many of the rheological and cooking functions may be viewed as displacement of the adjoining layers of the casein matrix. Hence, these factors exert their effect mainly by affecting the microstructural distributions of fat and protein and the degree of hydration (or aggregation) of the protein matrix in the raw and heated cheeses. Enzyme-modified cheeses may be dried to extend shelflife and/or for ease of use in specific ingredient formulations.
... The properties of cheese including Mozzarella depend on a number of factors such as type of milk used for cheese making, manufacturing protocol including acidification method of cheese milk, type of starter culture (SC) and rennet enzyme used, plasticizing treatment, etc. (Rowney et al., 1999;Jana and Mandal, 2011). Mozzarella cheese is traditionally manufactured from buffalo milk because of its characteristics flavor (Ghosh et al., 1990). ...
... The properties of cheese including Mozzarella depend on a number of factors such as type of milk used for cheese making, manufacturing protocol including acidification method of cheese milk, type of starter culture (SC) and rennet enzyme used, plasticizing treatment, etc. (Rowney et al., 1999;Jana and Mandal, 2011). Mozzarella cheese is traditionally manufactured from buffalo milk because of its characteristics flavor (Ghosh et al., 1990). ...
A 3×3 factorial arrangement of treatments in a completely randomized design was used to find out the combined effect of milk source {cow (CM), buffalo (BM) and mixed (CM:BM 1:1 ratio)} and the method of acidification {starter culture (SC): Streptococcus thermophilus, acetic acid (AA) and citric acid (CA)} of cheese milk on properties of Mozzarella cheese. Cheese made using BM and acidified with SC served as the control. Main effects of milk source and method of acidification of cheese milk showed a significant effect on yield of cheese whereas interaction effect was not observed. A significant interaction effect between milk source and method of acidification of cheese milk was observed for fat and protein percentages, meltability, b* value and sensory properties of resultant cheese. Fat and protein content was significantly higher in cheese made from BM acidified using AA and in control, respectively. Meltability was superior in Mozzarella cheese manufactured from CM acidified using CA compared to the control. Sensorily, Mozzarella cheese manufactured from mixed milk (CM: BM 1:1 ratio) acidified using CA obtained the highest mean score for all the sensory attributes and was significantly superior compared to the control. Therefore, the milk source and the method of acidification of cheese milk are closely linked to the yield and the quality characteristics of Mozzarella cheese and hence, careful selection of raw materials and manipulation of processing conditions are required to get an optimum quality end product.
... It is difficult to separate natural cheese from its analogue due to use of other ingredients in pizza. Functional characteristics, such as browning, melting, fat leakage and stretching, of cheese and its analogue have significant role in consumers' perception about quality of cheese (Rowney et al. 1999). Functional characteristics were analyzed after one week as one week ageing is suggested in case of natural cheese to get better baking properties (Guinee, 2002). ...
... Stretchability is defined as the capacity of melted cheese to form fibrous strands that extend without breaking under tension (Rowney et al., 1999). The ratio of the final-force to the peak-force is used as an indicator of stretchability. ...
To manufacture mozzarella cheese with customized attributes the relationships between processing parameters and cheese functionality need to be identified. In this study, cooking residence time (CRT) and stretching residence time (SRT) of cheese curd in the cooker-stretcher were determined to differentiate the effect of the cooking and stretching processes on cheese properties. Residence times were linked to cheese composition, micro- and macro-structural characteristics (microstructure, fat globule size, anisotropy and rheology) and functional properties (meltability, oiling-off, browning and stretchability). In the stretcher used, CRT was significantly longer than SRT independent of curd temperature or screw speed. Linear correlations were found between CRT and cheese composition, anisotropy and storage modulus. SRT had a less significant effect on cheese properties, due to the low specific mechanical energy 0.15-0.46kJ·kg⁻¹ and relatively short SRT. It was concluded that CRT and SRT are promising factors to understand and control mozzarella cheese characteristics during manufacture.
... manual or mechanical), the use of curd milling and cutting machines prior to stretching is recommended (57). (49,51,54,55,(58)(59)(60) shows different stretching conditions employed in mozzarella cheese processing. The literature reports stretching water temperatures of 50 to 85 °C and pH ranging from 5.0 to 5.5. ...
Mozzarella cheese stretching is a thermomechanical treatment influenced by factors such as pH, acidity, stretching time and temperature. The aim of this review was to provide information about the stretching step and the effect of the main factors on the functional properties of mozzarella cheese. The studies presented showed that stretching under higher temperatures promotes more interactions in the protein matrix, and changes occur in the calcium balance throughout the storage period that influence water mobility, proteolysis and lead to changes in mozzarella properties. Therefore, the information presented in this review may facilitate the production of mozzarella cheese with specific functional properties.
... Mostly, Mozzarella cheese is stored in refrigerator at 5°C in retail shops, fresh cheese is typically firm and has poor melting properties and although it will stretch, the overall texture will be unacceptable. However, as the cheese ages over a period of three weeks the texture becomes most suitable for preferable rheological properties (Rowney et al., 1999). Mozzarella cheese stored for longer period becomes extremely soft and fluid when melted and is no longer acceptable for pizza (Kindstedt, 1993), in addition with such longer storage period, some bacterial population increases and much of which are undesirable, causing spoilage of the cheese or may be pathogenic, representing public health hazard to consumers. ...
Thirty samples of Mozzarella cheese (15 made traditionally from raw milk in Tripoli city (Libya) and other 15 imported samples sold in markets related to different brand names) were examined bacteriologically for their total bacterial count, psychrophilic count, coliform count (MPN/g), presumptive Staphylococcus aureus count, as well as enterococci count. Higher counts were found in locally manufactured Mozzarella cheese. Salmonellae were absent in all examined samples for both types, while Escherichia coli were isolated from 3 samples (20%) of locally made samples. According to the suggested Libyan Standards of such samples, most of examined locally manufactured Mozzarella cheese samples were found unacceptable.
... Lower firmness was observed in cheese with higher fat content and in cheese with KGM addition. This is consistent with previous studies that Mozzarella cheese with lower fat content exhibited higher hardness, and may be because more casein has been deformed and the deformation of fat globules has been limited in fat-reduced Mozzarella cheeses (Rowney, Roupas, Hickey, & Everett, 1999;Tunick et al., 1993b;Tunick & Shieh, 1995). In addition, fat plays the role of lubricant, and it breaks up the protein matrix to provide a softer texture (Romeih, Michaelidou, Biliaderis, & Zerfiridis, 2002). ...
Konjac glucomannan (KGM) is a dietary fibre with potential to be used as a fat-replacer in Mozzarella cheese. The functional properties (texture, free oil, meltability and stretch performance) of full-fat cheese control (FFC), low-fat cheese control (LFC), skimmed cheese control (SKC), low-fat cheese with KGM (LF-KGM) and skimmed cheese with KGM (SK-KGM) after 0, 7, 14, 21 and 28 days of storage at 4 °C were measured. The pizza bake properties (appearance for pizza bake and browning) and microstructure were evaluated. Generally, LF-KGM and SK-KGM had lower firmness but higher meltability than LFC and SKC, respectively. The firmness and meltability of LF-KGM were similar to those of FFC. Both the stickiness and free oil content of LF-KGM and SK-KGM were similar to LFC and SKC, respectively. The LF-KGM and SK-KGM showed more complete shred melt, less scorching and lower browning (higher L* value after baking) on the cheese surface than LFC and SKC, respectively, when they were baked as a pizza topping. Microstructure of FFC, LFC and SKC showed that fat globules filled the serum pores/channels in the protein matrix. LF-KGM and SK-KGM showed more dense protein matrix with more coalesced fat globules distributed in the matrix. The stickiness, free oil content and meltability of all the cheeses increased but firmness decreased during storage. We show that KGM may be useful as a fat replacer in manufacturing fat-reduced Mozzarella cheeses to improve functionality and pizza bake characteristics.
... The functional prepared from whole buffalo milk at the Laboratory of properties attributed to melted Mozzarella cheese are Animal Products Technology. Buffalo milk procured from widely varied which is largely responsible for consumer Livestock Experiment Station, Faculty of Animal perception (Rowney et al., 1999). Defects associated Husbandry and Veterinary Sciences, Sindh Agriculture with Mozzarella cheese include a rubbery, tough texture, University, Tandojam, was used during the experiment. ...
Mozzarella cheese was prepared from buffalo milk using liquid rennet extracted from calf stomach
... The second phase involves plasticization of the heated curd and an internal reorganization of the cheese microstructure into fibrous strands during passage through the cooker/stretcher. The final phase entails cooling of the hot mass of cheese, usually with concomitant salt uptake that sets the stage for development of the varied functional properties of melted LMMC responsible for consumer perceptions (Rowney et al., 1999). ...
Modern methods of manufacturing of low moisture mozzarella cheese (LMMC) are compared to traditional methods with an emphasis on cheese made for use on pizza since world-wide production of such LMMC far exceeds that of other pasta-filata cheeses. Factors that influence each phase of manufacturing of LMMC are described from conversion of milk into cheese curd, plasticization of curd during the pasta-filata process, through cooling, brining, and storage of the cheese. Acid development by the starter cultures contributes to modifying the chemistry of cheese curd through its influence on obtaining the level of protein-bound calcium needed for proper plasticization of the curd in the cooker/stretcher. Design of the cooker/stretcher along with the thermal and mechanical energy input, influences the temperature of the cheese during plasticization which influences the composition and functional properties of LMMC after cooling. The type of starter culture and coagulant used and their survival during the pasta-filata process influences the rate of proteolysis occurring and the subsequent changes in LMMC properties during refrigerated storage. Alternatively, LMMC can be frozen to prevent such changes. The importance of the functional properties of LMMC, such as melting, stretching, browning, and blistering are related to its performance during the baking process of making a pizza.
... Homogenization of milk reduces milk fat globule size and alters milk fat globule membrane (MFGM). It is also believed to create a new fatwater interface predominantly containing caseins that can make fat globules more stable (Rowney et al., 1999). Thus an increase in the area of lipid/water interface and redistribution of some of the casein makes a network that can retain more moisture and hence increase in the yield of final product. ...
The purpose of this study was to determine the impact of key process parameters on the flow properties of a novel High Protein Dairy Food (HPDF). HPDF was manufactured by an approach similar to that of manufacture of Halloumi cheese (a semi hard cheese originally from Cyprus). The effect of pasteurization condition, pH of acidification and homogenization were investigated on flowability, composition and texture of the HPDF. The study consisted of three different stages. After each stage of experimentation, the HPDF was analyzed for compositional, textural (by texture profile analysis) and flow properties during heating by microwave, oven and hot water was measured by Schreiber melt test. The first stage of experimentation screened 18 batches of HPDF under three levels of pasteurization conditions (191°F/16 sec, 175°F/16 sec and 161°F/16 sec), three levels of pH of acidification (5.8,6.2 and 6.6) and two levels of homogenization conditions (two stage homogenization (2000 psi/500 psi) and no homogenization). Based on the results of the first stage, a statistically powerful second stage of experiment was designed in which two levels of pasteurization condition (191°F/16 sec and 161°F/16 sec) and three levels of pH of acidification (5.8, 6.2 and 6.6) were employed in duplicate to manufacture HPDF. The third stage of experimental design was to investigate the effect of two-stage homogenization treatment (2000 psi/500 psi) with two levels (homogenization and no homogenization). The results of all three stages of experimentation proved that HPDF made from milk pasteurized under higher pasteurization condition (191°F/16 sec) had significantly higher flow resistance under all three heating conditions. There was significant interaction between pH of coagulation of milk and pasteurization condition on flow properties of HPDF with pH of coagulation 5.8 restriction flow of HPDF under all three heating conditions. The role of homogenization in restricting flow of HPDF was not significant, although the mean flow of HPDF, made from homogenized milk, decreased. The mean protein content and mean moisture content of HPDF was significantly affected by all three processing conditions, although the mean fat content of HPDF was not influenced by any of these conditions. The mean fat, protein and moisture content of HPDF were in the range of 10.5-11, 26-34 and 47-54 percent respectively. The primary textural properties affected significantly by the processing condition were hardness, chewiness and gumminess. Particularly, hardness was influenced by higher pasteurization condition and lower pH of acidification. Further, to judge the consumer acceptability of HPDF, various recipes made out of HPDF with different heating applications (baking, stir-frying and soup) were served to 12 panelists of DPTC. Their opinions were collected and analyzed statistically. The analysis of limited focus group survey showed that consumer liking for HPDF recipe was significantly influenced by prior familiarity with the recipe, although there was some preference for HPDF over tofu due to its ‘dairy’ flavor. When the texture of HPDF manufactured from milk pasteurized at 191°F/16 sec and pH of acidification 5.8 and 6.2 were compared with various commercial protein sources, the hardness of the HPDF was very close to extra firm tofu. All the other textural properties of HPDF were significantly different from firm, silken, baked or reduced fat tofu. From this project, it is evident that a high protein food, which can be part of day-to-day human diet and potential tofu alternative, can be obtained using halloumi approach by optimizing pasteurization condition (191°F/16 sec) and pH of coagulation (5.8).
... Cheeses such as mature Cheddar, Emmental, Raclette and Gouda are more satisfactory for the latter applications because of their higher degree of proteolysis, excellent flowability and flavour and absence of stringiness on grilling. Many parameters contribute to the functional characteristics of heated cheese products ( Rayan et al., 1980;Harvey et al., 1982;Paulson et al., 1998;Rowney et al., 1999). The concentration and type of protein (i.e., casein or whey proteins), degree of calcium-induced crosslinking ( Guinee et al., 2002;Metzger et al., 2001;Pastorino et al., 2003b), the pH, which affects the ratio of caseinbound calcium-to-soluble calcium ( Pastorino et al., 2003a), and the extent of protein hydrolysis are major determinants of functionality ( Arnott et al., 1957;Schulz, 1976;Lazaridis et al., 1981;Mahoney et al., 1982;Lawrence, 1989;Rüegg et al., 1991;Yun et al., 1993a, b;Kindstedt, 1993Kindstedt, , 1995Bogenrief and Olson, 1995;Guinee et al., 2000a, b;Kaláb et al., 1991;Rynne et al., 2004). ...
Cheese manufacture involves the controlled destabilization of the casein micelle in milk by enzymatic hydrolysis of the surface ê-casein layer, acidifi cation to the isoelectric pH of the casein, or a combination of pH reduction to ~5.6 and high temperature (~90 °C) in rennet-curd, acid-curd and acid heat-curd cheeses, respectively. Under suitable conditions, the destabilized micelles undergo limited aggregation to form a gel, which is dehydrated to a curd with the desired moisture content by a series of unit operations including cutting the gel into pieces (curd particles), in situ acidifi cation, heating and stirring the curd particle/whey mixture, removal of the expressed whey, pressing and/or salting of the curd. Microstructurally, rennet-curd cheese is a matrix comprised of a hydrated calcium phosphate para -casein network that occludes the fat phase which occurs as discrete and coalesced globules or pools. The microstructure is infl uenced by the concentration of para -casein and the degree to which the component para - casein micelles are aggregated and fused, as affected by manufacturing operations. Macrostructurally, rennet-curd cheese is an assembly of curd particles or pieces (e.g., chips) that fuse to varying degrees according to their microstructure, which affects their potential to deform, and curd handling treatments (e.g., pressing) which effect the level of stress applied to the amalgam of curd particles/pieces. The matrix of acid- or acid heat-curd cheese is similar to that of rennet-curd cheese, but the network is formed from casein (with little, or no, bound calcium) or casein complexed with whey protein, denatured by high heat treatment of the milk prior to acidifi cation and gelation. Most acid-curd and acid heat-curd cheeses have a very uniform texture and lack a macrostructure as the curd particles, low in calcium and high in moisture, coalesce easily to form a structuralcontinuum. Heating of rennet-curd cheese to 90-100 °C in culinary applications leads to contraction and shrinkage of the para -casein network and liquefaction and coalescence of fat. These microstructural changes are the basis of the melt properties, including softening, fl ow and stretchability. Owing to their low pH, acid-curd cheeses generally tend to be unstable during heating, as refl ected by protein precipitation and the release of excess free moisture. The micro- and macro-structure of cheese has a major infl uence on various aspects of quality including composition, rheology, texture, cooking properties, opacity/translucence, and behaviour during curd processing operations such as portioning, shredding, slicing, and processed cheese manufacture
... The functional prepared from whole buffalo milk at the Laboratory of properties attributed to melted Mozzarella cheese are Animal Products Technology. Buffalo milk procured from widely varied which is largely responsible for consumer Livestock Experiment Station, Faculty of Animal perception (Rowney et al., 1999). Defects associated Husbandry and Veterinary Sciences, Sindh Agriculture with Mozzarella cheese include a rubbery, tough texture, University, Tandojam, was used during the experiment. ...
Mozzarella cheese was prepared from buffalo milk using liquid rennet extracted from calf stomach at the Laboratory of Animal Products Technology, Sindh Agriculture University Tandojam. All the cheese batches were evaluated for compositional, rheological and sensory characteristics. The mean moisture content of mozzarella cheese was 55.15±0.88%, whereas, protein, non protein nitrogen and fat content was 25.28±0.45, 1.56±0.07 and 15.69±0.29%, respectively. The average ash and chloride content was observed as 3.42±0.10 and 1.60±0.02%, respectively. The meltability and strechability of mozzarella cheese was observed as 6.11 ±0.16 and 12.75±0.15cm, respectively. The sensory attributes showed that color/appearance of mozzarella cheese perceived 4.10±0.27 score, the score for flavor of mozzarella cheese was 27.90±0.43 and the body/texture received 23.60 ±0.52 score. It was concluded that average moisture content of mozzarella cheese revealed that the product was under high moisture category cheese, regardless the fat, meltability and strechability concludes it to be used primarily as an ingredient for pizza making.
... INTRODUCTION Global production of Mozzarella cheese has grown dramatically during the period 1985 to 2000 (Rowney et al., 1999), especially in the United States, where annual production in 1996 was 1.03 million tonne (Sørensen, 1997). The main impetus for the growth of Mozzarella has been the increased in the popularity of pizza, in which Mozzarella is a main ingredient. ...
... Second, starter cultures produce enzymes that affect cheese flavor and texture (Rowney et al.1999, Ahmed et al. 2011). ...
Many factors influence the texture of cheese such as: manufacturing, procedure variety and composition and bio chemical changes during ripening. Texture is the sensory and functional manifestation of the structural, mechanical and surface properties of foods detected through the senses of vision, hearing, touch, and kinesthetic. Cheese has a complex structure that causes differences, even within the same variety of cheese, which depend on compositional factors and their changes during processing techniques and storage conditions. In order to be able to fully understand what determines cheese quality and texture, it is necessary to have an understanding of the physical and chemical mechanisms that occur during cheese processing.
... 치즈 고형분 함량 중 지방함량이 임계수준이상일 경우 치즈에 존재하 는 지방구의 총 표면적이 너무 커서 casein의 자연유화작 용이 불안정화 되어 지방분리가 생성된다고 보고되었다 (Shimp, 1985). 이러한 지방분리는 냉장보관 중에도 casein 이 분해되어 유화능력이 감소되어 냉장보관 시간이 증가 할수록 증가한다(Nilson, 1974;Tunick, 1994).Table 5). 신전성은 점질성(stringiness)이라 하기도 하며 용융된 치 즈가 섬유형태로 길게 늘어나는 경향을 말하며, 수분함량, 지방함량 등 다양한 요인에 의하여 영향을 받는다(Smith et al., 1980). ...
Low-fat and full-fat Mozzarella cheeses were manufactured using ultraflterated-concentrated cow milk with a bacterial cell count of 100, 000 CFU/mL to study the properties of browning, oiling-off, stretchability, and meltability of the cheeses during 3 mon of refrigerated storage. The properties of browning, oiling-off, and stretchability of UF-Mozzarella cheese were affected by fat content, addition of starter and rennet (add 50, 65, and 80% compared with the control, respectively), and baking temperature (280, 300, and 320°C) (p<0.05). The browning and oiling-off scores increased with an increase in baking temperature and lengthen of storage time, but some undesirable results also occurred. The stretchability score improved with an increase in baking temperature, but the gradient decreased with the length of storage time (p<0.05). The meltability score was affected by fat content, concentration factor, and storage period (p<0.05). The result of this study demonstrated the applicability of UF-milk in making Mozzarella cheese with high quality and good palatability.
... Functional properties The functionality of heated mozzarella depends on several factors such as meltability, stretchability, free oil formation, and browning. These properties play heavily on consumer perceptions of cheese quality (Rowney et al. 1999). ...
The objective of this study was to improve the physicochemical properties and functional qualities of soy based mozzarella cheeses by ultrafiltration (UF) of soy milk blends, adding skim milk instead of cow's milk or increasing the soy milk proportions in cheese milk. Eight types of moz-zarella cheeses made using soy milk and analyzed for nutritional , structural, and functional characteristics for 4 weeks at 4 °C. Cheeses made with cow milk, 10, 20, and 30 % soy milk in cow milk, skim milk, 10 % soy milk in skim milk, and ultrafiltrated 10 % soy milk in cow milk for first and second volume concentrations. Refrigerated storage of the soy-mozzarella led to a decrease in total solid, mineral, protein, fat, and lactose contents and rheological characteristics after 2 weeks. The nutritive quality of the mozzarella tended to increase proportionally to soy milk content, but the physical and functional qualities decreased. The UF-fortified soy-moz-zarella showed more improved qualities among the other soy cheeses like long shelf life, improved nutritional, structural and functional qualities. Blends of 10–20 % soy milk and UF soy milk blends can be used to achieve good quality, nutritive mozzarella cheese, even with skim milk instead of cow milk in a milk shortage.
... The fresh cheese was typically firm and has poor melting properties and although it was stretchable. However as the cheese matures, the texture softens and there is an increase in melt (Rowney et al., 1999). The improvement in meltability is due to dislodgement of para-casein matrix (Sheehan and Guinee, 2004). ...
Three mozzarella cheeses were prepared from three different milk sources i.e. cow (C), buffalo (B) and their mix (A) milks using DL (Streptococcus lactis and cremoris; S. Diacetalactic, Leuconostoc cremoris) and yoghurt cultures. Milk was standardized to C/F: 0.90/0.92 and process optimized for using all milk sources. The samples were analyzed for physico-chemical and functional properties, sensory attributes and protein and fat losses. Except ash and yield at 50% moisture; fat, protein, actual yield, pH, acidity and moisture were significantly influenced by milk sources. From sensory result, cow and mix cheeses were significantly superior, whereas functional properties were superior for cow cheese but buffalo and mix cheeses had higher nutritive value. From overall comparison, cow mozzarella cheese was ranked most suitable for pizza topping. J. Food Sci. Technol. Nepal, Vol. 6 (94-101), 2010 DOI: http://dx.doi.org/10.3126/jfstn.v6i0.8268
... The functional prepared from whole buffalo milk at the Laboratory of properties attributed to melted Mozzarella cheese are Animal Products Technology. Buffalo milk procured from widely varied which is largely responsible for consumer Livestock Experiment Station, Faculty of Animal perception (Rowney et al., 1999). Defects associated Husbandry and Veterinary Sciences, Sindh Agriculture with Mozzarella cheese include a rubbery, tough texture, University, Tandojam, was used during the experiment. ...
Mozzarella cheese was prepared from buffalo milk using liquid rennet extracted from calf stomach
at the Laboratory of Animal Products Technology, Sindh Agriculture University Tandojam. All the cheese
batches were evaluated for compositional, rheological and sensory characteristics. The mean moisture
content of mozzarella cheese was 55.15±0.88%, whereas, protein, non protein nitrogen and fat content was
25.28±0.45, 1.56±0.07 and 15.69±0.29%, respectively. The average ash and chloride content was observed
as 3.42±0.10 and 1.60±0.02%, respectively. The meltability and strechability of mozzarella cheese was
observed as 6.11±0.16 and 12.75±0.15cm, respectively. The sensory attributes showed that
color/appearance of mozzarella cheese perceived 4.10±0.27 score, the score for flavor of mozzarella cheese
was 27.90±0.43 and the body/texture received 23.60 ±0.52 score. It was concluded that average moisture
content of mozzarella cheese revealed that the product was under high moisture category cheese,
regardless the fat, meltability and strechability concludes it to be used primarily as an ingredient for pizza
making.
Key words: Composition, rheology, sensory attributes, mozzarella cheese
... These also influence the customer's acceptance in terms of cheese quality and end use applications. According to Rowney et al. (1999), end use of cheese on different food products depend on the variety of functional properties. The term meltability is most commonly applied to define cheese functionality. ...
Four treatments of natural Cheddar cheese with two levels (high and low) of calcium (Ca) and phosphorus (P), and two levels (high and low) of residual lactose were manufactured. Each treatment was subsequently split prior to the salting step of cheese manufacturing processed and salted at two levels (high and low) for a total of eight treatments. The eight treatments included: high Ca and P, high lactose, high salt-in-moisture (S/M) content (HHH); high Ca and P, high lactose, low S/M (HHL); high Ca and P, low lactose, high S/M (HLH); high Ca and P, low lactose, low S/M (HLL); low Ca and P, high lactose, high S/M (LHH); low Ca and P, high lactose, low S/M (LHL); low Ca and P, low lactose, high S/M (LLH); and low Ca and P, low lactose, low S/M (LLL). After 2 months of ripening, each treatment of natural Cheddar cheese was used to manufacture processed cheese using a twin-screw Blentech processed cheese cooker. All of the processed cheese food formulations were balanced for moisture, fat and salt. Texture and melt-flow characteristics of the processed cheese were evaluated with different techniques, including texture profile analysis (TPA) for hardness and melt profile analysis. There was a considerable increase in cheese hardness for the processed cheeses prepared from high Ca and P content, and high S/M natural cheeses compared with low Ca and P content and low S/M natural cheeses. Moreover, definite decrease in flow rate and extent of flow was observed for processed cheeses manufactured from high Ca and P content, and high S/M natural cheeses than that of low Ca and P content and low S/M natural cheeses. No considerable trend was observed in hardness and melt-flow characteristics for the processed cheeses manufactured from high and low residual lactose content natural Cheddar cheeses. This study strongly demonstrates that the characteristics of natural cheese (calcium and phosphorus content, lactose content and salt-in-moisture content) used in processed cheese manufacture have a significant impact on processed cheese functionality.
... Many factors can influence texture, melting, and stretching properties of cheese. These include cheese composition, pH, and interactions between casein and serum proteins, proteolysis, Ca content, ionic strength, salt content, and manufacturing protocols (McMahon et al., 1993;Rowney et al., 1999;Guinee et al., 2002). ...
The objective of this study was to determine the effect of stretching pH on technological parameters and physicochemical and texture characteristics of the pasta filata cheese Telita. A no-brine cheese-making method was used to control both melting and stretching temperatures. Six vats of cheese, each with a different stretching pH (5.2, 5.3, 5.4, 5.5, 5.6, and 5.7), were made in 2 h. Cheese-making was replicated using 2 different lots of milk. Differences in stretching pH significantly affected all variables evaluated; stretching temperature and pH were positively correlated. Technological parameters showed an inverse relationship between pH and acidity and a direct relationship between melting and stretching temperature. The yield was highest as the pH increased and ranged from 11.4 to 12.9 kg of cheese/100 kg of milk. Physicochemical characteristics showed the following: moisture 48.1 to 53.5% (soft and semi-hard cheese), fat 46.3 to 54.9% (dry basis, full-fat cheese), minerals 2.8 to 3.5% (dry basis), calcium content 0.5 to 1.0% (dry basis), sodium 0.38 to 0.78% (dry basis), and whiteness index 77.2 to 84.5. Texture parameters showed that as the stretching pH increased, hardness increased, adhesiveness decreased, cohesiveness decreased, springiness increased, and chewiness increased. Samples were grouped based on principal component analysis. Group 1 contained cheeses at pH 5.2 and 5.3 and were better in terms of retention of components. Group 2 contained cheeses at pH 5.6 and 5.7. These cheeses attained the highest yields, were whitest, and presented the highest values for texture parameters except for adhesiveness and cohesiveness. The third group of cheeses at pH 5.4 and 5.5 were considered the best because they showed a good balance among all variables evaluated.
... Free oil (FO) formation, also known as oiling off or fat leakage, occurs during the heating of mozzarella cheese. Release of oil results from the collapse of the casein matrix allowing fat globules to coalesce and migrate to the surface where pools of FO are formed (Rowney et al. 1999). Fat globule size, location within the casein matrix, and degree of agglomeration all are related to the formation of FO in mozzarella cheese (Rowney et al. 1998). ...
Mozzarella cheese was made from buffalo milk (6% fat) or from partially skimmed buffalo milk (2 and 4% fat) with 0.5 and 1% denatured whey protein. Adding whey protein to buffalo milk decreased rennet coagulation time and curd tension whereas increased curd synaeresis. Addition of whey protein to cheese milk increased the acidity, total solids, ash, salt, salt in moisture, also some nitrogen fractions. The meltability and oiling-off values increased but the calcium values of mozzarella cheese decreased. The sensory properties of low fat mozzarella cheese were improved by addition of whey protein to the cheese milk.
... Meltability , flow-ability, oiling-off during cooking and slice-ability are terms describing cheese functionality, and the criteria for each term differs with cheese type. For example, melt-ability, stretch-ability, amount of free-oil and browning are important for Mozzarella cheese (Rowney et al. 1999). Processed cheese improves on the functional properties of natural cheeses by blending ingredients and controlling processing conditions (Fox et al. 2000 ). ...
Textural and functional properties of processed cheese are affected by a final production step – cooling. Rheological data demonstrate a firmer cheese at slower cooling rates. To simulate industrial production, five-pound cheese loaves were cooled in an environment at 5C under free and forced convection. Slice-ability was estimated by cutting loaves at different locations using a wire-cutting device, and melt-ability was determined by the Schreiber method. Cooling rates, estimated from a heat transfer model, did not show a large difference within the five-pound loaf, and no obvious trends in slice-ability and melt-ability were observed. Comparing forced with free convection, a smaller force was required to slice the cheese, and a higher melt score was experienced for the forced convection scenario. Cheese manufacturers can benefit from this research by manipulating cooling schedules to achieve desired textural attributes of processed cheese.
The chapter provides a comprehensive review of the various aspects of processed cheese's manufacture, including formulation, blending, and processing. It determines the effect of packaging materials on quality indicators of processed cheeses. The variations in composition and processing conditions of the processed cheeses control the diversity in packaging format and shape. Moreover, the chapter considers how the cooling rate affects the physical and rheological properties as well as the functionality and the microstructure of the final processed cheese products. Indeed, many factors can contribute to the development of the structure of the final product during the cooling phase namely fat crystallization, incorporation of recombinant fat globules, and protein-protein interactions. Finally, it discusses the shelf life of processed cheese products as well as the possible physicochemical, sensory and rheological changes and their relevance during the storage period of processed cheese.
Manufacture of mozzarella cheese designed for use on a pizza and other baking applications. An emphasis is placed on factors that influence the functional properties of the cheese such as the role of fat, protein-protein interactions and proteolysis, calcium, starter cultures, and the cooking/stretching process that is characteristic of pasta filata cheeses.
Mozzarella cheese is a soft, un-ripened cheese variety of the Pasta filata family which had its origin in the Battipaglia region of Italy (Citro, 1981). Conventionally, Mozzarella cheese was made from buffalo milk. However, these days it is being manufactured in Italy, in other European countries and USA from cow milk which needs appropriate modifications (Ghosh et al., 1990). The cheese is white, soft with a glossy surface and is valued for its stretch property. In Italy Mozzarella and pizza cheese accounts for 78% of the total Italian cheese production (Merrill et al., 1994).
Mozzarella is still America’s favorite cheese, U.S. cheese availability stood at 33.5 pounds per person in 2014. Mozzarella and Cheddar together accounted for 62% of cheese availability in 2014. Per capita cheese availability has almost tripled since 1970, when it was 11.4 pounds per person (Sam Brasch, 2014).
Plastic curd or “Pasta filata” cheese family consists of a large distinguished cheese varieties produced mainly in Italy, Eastern European and Balkan Peninsula and Middle Eastern Arab countries (Abou Donia, 2005).
The production of the plastic curd cheese was highly increased in all of the Egyptian provinces during the last decades because the fresh curd after kneading treatment in hot water of the above cheese varieties could be utilized as a topping on pizza, but the most known one in that concern is Mozzarella cheese (Abou Donia, 2005).
In the Middle East mozzarella cheese is known as Al- Medaffarah or Al-Meshallela cheese because the cheese has the shape of girl plait. The curd of this cheese was made from ewe milk by sheep shepherds, while kneading and molding were done by house wives. The cheese was preserved for year round in saturated brine (Abou-Donia and Abdel-Kader, 1979).
According to Ahmed (2004) the special characteristics of Mozzarella cheese are, soft and normally white in color, must be shareable to enable homogeneous distribution, fibrous structure, good melting and stretching properties, mild aroma and flavor and consumed in the melted state and specially used as pizza topping. Mozzarella cheese contribute to the organoleptic characteristics of most foods in which it is incorporated by possessing certain; taste, aroma, texture and mouth coating characteristics. Upon grilling or baking it is required to melt, flow, brown, blister, oil-off and / or stretch to varying degrees. It is also expected to be chewy and contribute to certain mouth coating characteristics.
The Egyptian Organization of Standardization and Quality Control ES: 1008-14/2005 part 14, defined Mozzarella cheese as a soft cheese, moisture should not exceed 54%, fat not less than 45% as fat/DM for whole milk cheese, In case of 3/4 of milk fat, fat content of cheese not less than 35% Fat/DM and moisture content not exceed 57%. As for 1/2 milk fat, Fat /DM not less than 25% and moisture not exceed 60%. Whey proteins in Mozzarella cheese not more than 23% of total protein.
In Egypt there is a shortage in milk production since there is a challenge between, growing green forage for cattle feeding and wheat production for human consumption prices of fresh milks are annually increasing, most of buffalo milk was consumed for drinking, while a part of cow milk is processing into soft white cheese, and Ras cheese, the rest is not enough for Mozzarella production. On the other hand, people are eager to consume natural butter or butter oils of cows or buffalos milk leaving the skim milk of buffalo and cow milk for low price Kareish cheese. Mozzarella cheese from whole cow or buffalo milks is costly, at mean time processors did not highly succeed to manufacture high quality cheese from skimmed cow, buffaloes and powder milks containing palm oil, which is permitted by the Ministry of Health and Population, so the aim of this investigation is to run the alternative experiments for utilizing the skim milks with palm oil for the production of high quality mozzarella cheese. To answer the questions of processors and consumers, processors search for high yield and good marketing, while consumers searching for high rheological proportion mozzarella cheese for pizza making.
The current study explored the effect of intramuscular injection of vitamin B12 (VB12) in early-lactation dairy cows on subsequent low-moisture part-skim Mozzarella cheese quality and VB12 levels during cheese processing and storage. Twenty-four peripartum dairy cows were blocked based on parity and milk yield and randomly assigned into 2 treatments: basal diet (CON) and basal diet with an intramuscular injection of 10 mg of VB12 per cow per week (VB12). Raw milk was collected to determine VB12 content and then used to make low-moisture part-skim Mozzarella cheese 8 wk after injection. The VB12 content of raw milk and cheese was determined using ultra-performance liquid chromatography coupled with tandem mass spectrometry. We found that VB12 content was significantly increased in milk (15.43 vs. 3.30 ng/mL) and fresh cheese (3.72 ng/g vs. undetectable) from the VB12 group compared with the CON group. However, approximately 70% of VB12 was lost in the whey during cheese making, and no VB12 was detectable in either cheese treatment after 8 wk of storage. Furthermore, no significant differences were observed in fat and protein contents in the cheese between the 2 groups. For cheese color, the b* value increased and the a* value decreased slightly in fresh VB12 cheese (P < 0.05). Functional properties of stretchability, flowability, and meltability of VB12 cheese were initially comparable to that of CON cheese (P > 0.05), but higher flowability and meltability was observed in VB12 cheese after 8 wk of storage (P < 0.01). In summary, intramuscular injection of VB12 in early-lactation dairy cows increases the content of VB12 in milk and fresh cheese with no adverse effect on cheese quality, but substantial VB12 is lost during cheesemaking and declines rapidly during storage.
Cheese is an extremely versatile food product that has a wide range of flavor, textures and end uses. The vast majority of cheese is eaten not by itself, but as part of another food. As an ingredient in foods, cheese is required to exhibit functional characteristics in the raw as well as cooked forms. Melting, stretching, free-oil formation, elasticity and browning are the functional properties considered to be significant for Mozzarella cheese. When a cheese is destined for its end use, some of its unique characteristics play a significant role in the products acceptability. For instance pH of cheese determines the cheese structure which in turn decides the cheese shredability and meltability properties. The residual galactose content in cheese mass determines the propensity of cheese to brown during baking. Development of ‘tailor-made cheese’ involves focusing on manipulation of such unique traits of cheese in order to obtain the desired characteristics for its end use application suiting the varied consumer’s whims and wishes. This comprehensive review paper will provide an insight to the cheese maker regarding the factors determining the functional properties of cheese and also for the pizza manufacturers to decide which age of cheese to be used which will perform well in baking applications.
Study the characteristics of Mozzarella cheese manufacturered by using denatured whey protein or Goat's milk.
Mozzarella cheese is a classical dairy product but most research to date has focused on low moisture products. In this study, the microstructure and physicochemical properties of both laboratory and commercially produced high moisture buffalo Mozzarella cheeses were investigated and compared to high moisture bovine products. Buffalo and bovine Mozzarella cheeses were found to significantly differ in their microstructure, chemical composition, organic acid and proteolytic profiles but had similar hardness and meltability. The buffalo cheeses exhibited a significantly higher ratio of fat to protein and a microstructure containing larger fat patches and a less dense protein network. Liquid chromatography mass spectrometry detected the presence of only β-casein variant A2 and a single β-lactoglobulin variant in buffalo products compared to the presence of both β-casein variants A1 and A2 and β-lactoglobulin variants A and B in bovine cheese. These differences arise from the different milk composition and processing conditions. The differences in microstructure and physicochemical properties observed here offer a new approach to identify the sources of milk used in commercial cheese products.
In order to study the effect of microfiltration technology on Mozzarella cheese the hydraulic pressure and scanning electron microscopy were used to determine its expressible serum and microstructure during 10-day storage at 4°C. It is indicated that the difference of physiochemical component between microfiltrated Mozzarella cheese and control Mozzarella cheese is not significant except moisture, calcium and phosphate content (p>0.05). The expressible serum/moisture in both of Mozzarella cheeses decreases with ripening period prolonged and the buffering capacity is higher in microfiltrated cheese. The casein matrix absorbs free water and the expressible serum channel is narrowed during the ripening period. The casein matrix becomes more smooth and homogeneous, and the channel becomes more porous in control Mozzarella cheese, which correlate with the nature of cheesemilk.
Low-moisture part-skim (LMPS) Mozzarella is a commodity cheese whose composition, production, and functionality are strongly linked to its use as pizza cheese. Its traditional manufacture follows that of most pasta-filata or stretched cheeses in that after curd formation, and sufficient syneresis and acid development, the curd is heated and mechanically stretched, then formed into shape, cooled, brined, and vacuum packaged. Many innovations have been implemented in its large-scale manufacture to lower cost, shorten make time, simplify use in the food service industry, or modify baking performance. LMPS Mozzarella needs only a few weeks of aging to develop the desired properties, or if moisture, fat, and calcium levels are correct it can be shredded for immediate use and frozen for storage and delivery. When LMPS Mozzarella is melted, it forms a homogeneous mass with sufficient flow, so shreds fuse together while enough calcium-mediated interactions occur between proteins to retain some elasticity (stretch). Thermophilic starter cultures, such as Streptococcus thermophilus and Lactobacillus helveticus in combination, or St. thermophilus alone, are used to slow proteolysis and provide a longer time before the cheese becomes too soft to shred. The fibrous structure of LMPS Mozzarella allows it to be sold as an individually wrapped ‘string’ cheese.
Low moisture part-skim Mozzarella cheeses (MC) were manufactured using fresh bovine and caprine milk to study melting, physico-chemical, textural, and microstructural properties of the cheeses during 8 wk of refrigerated storage. Structural changes in cheese matrix were evaluated by scanning electron microscopy and by proteolytic patterns using nitrogen solubility, SDS-PAGE, and Gel-pro analyzer. Meltability of ripened cow and goat MC were not different when fat content of both milks were standardized, whereas bovine MC formed a significantly larger amount of free oil throughout the experiment. The results of the proteolytic patterns, texture attribute (cohesiveness), and microstructure revealed that bovine MC had a greater structural degradation of cheese matrix than caprine MC during the storage. Elevated protein degradation in bovine MC led to more intense brown color formation than the goat counterpart when the cheeses were baked. The melting characteristics showed high positive correlation (r = 0.51 to 0.80) with proteolysis, whereas it was negatively correlated with textural characteristics. Among textural attributes, cohesiveness was highly inversely correlated with melting characteristics (r = -0.69 to -0.88). High negative correlations were also observed between proteolytic parameters and textural attributes (r = -0.48 to -0.81).
Cheese, which accounts for ~30% of total milk usage, is a dairy product of major economic importance. World production of cheese is ~15 x 106 tonnes per annum, with an estimated value of US$ 5.5 x 1010. Approximately 7% of total production is traded on the global market, the major suppliers being the EU (~50%), New Zealand (~16%) and Australia (~11%) (S0rensen, 1997).
Sales of PDO cheeses undergo a decline. The use of these cheeses in the form of ingredient represents an interesting alternative to the tasting and would allow to maintain a sustainable business activity to the producers of these cheeses. The objective of this work is to investigate the potentialities of four categories of Blue cheese PDO of the Massif Central as an ingredient to meet their properties during heating such as "melting, stretchability, browning". The functional properties desired for this type of cheese have been investigated by physico-chemical methods and instrumental classics and also by spectral method and sensory evaluations to enrich the observations of the macro and microstructure of the cheese and the consumer perception. First, the physicochemical, rheological, sensory characteristics and certain properties during heating have been reported for four categories of Blue cheese. These initial results allowed us to characterize the cheese studied according to their characteristics essentially which were related to the organization matrix constitutes such as proteins, fats, minerals. The sensory analysis allowed to describe exactly certain properties which are not revealed by theother analyses. Blue-veined cheeses have a great heterogeneity due to the presence of "veins" of mold. The second part is a study on the ability of the SFS method to study the micro structure and to predict the diversity of composition of these cheeses. Despite the high heterogeneity of cheeses, SFS allows an identifiable 'fingerprint' of cheese and predicts some but not the totality of the physicochemical parameters. The evolution of the macro-and microstructure of these cheeses during heating and cooling was then studied by SFS and dynamic shear test. These methods describe well the melting temperature of the fat and the cheese matrix. They are correlated between them and demonstrate a relationship between the molecular structure and the rheological properties of these cheeses. A comparative study of the sensory textural properties of cheeses was carried out in the non- and heated forms. The attributes describe different characteristics of texture between the two conditions. This approach allowed to differentiate well the four categories of cheeses and to highlight on certain attributes of quality or defects to be used in cooking application. In conclusion, these four categories of Blue-veined cheeses have the potential to be used as an ingredient in cooking application. The sensory analysis characterized the perceptions of the consumers in both non- and heated forms and thus helps to specify their features. The rheological and spectral analyses have provided explanations related to this treatment at the level of the macro and microstructure of the cheese matrix.
Milk samples with low (L-SCC, 130,000/ml), medium (M-SCC, 1,040,000/ml) and high(H-SCC, 3,120,000/ml) Somatic Cell Counts (SCC) were obtained from a dairy farm. In order to evaluate the quality’s changes of Low-fat mozzarella cheese with different SCC during ripening period, the change of texture properties, microstructure were measured. With the increase of somatic cells in milk, the structure of the cheese became worse.
ABSRACT Mozzarella cheese was made using UF-retentates TS ~20g100 –1 from cows and buffaloes milks. It was also made from difiltered and direct acidified retentates to reduce the calcium content in the retentate to achieve objective the firmness of the curd. The fresh cheeses were analyzed when fresh and after storage for one month at ~5°C for chemical, physical, rheological and organoleptic properties. The obtained results revealed that Mozzarella made from cow milk and its retentates exhibited much better ripening indices and rehological properties cheeses. The UF-tech-nique lowered the moisture content, lactose, ripening indices, meltability and oilling off in the resultant cheese, while it elevated protein content and yield. Diafiltration processe decreased Ca ++ , P ++ , lactose, ripening indices, while its effect on rehological properties was low. Acidification process either to the normal milk or to the retentats decreased Ca ++ , P ++ , lactose, ripening indices and meltabilty of the produced cheese. Storage increased all constituents in all treatments except lactose and improved the meltability and oilling off. Sensory evaluation revealed that the Mozza-rella cheese from UF-cows' retentate was the best treatment and similar to that from traditional one, while the cheese made from buffaloes' milk had some defects.
ABSRACT Mozzarella cheese was made using UF-retentates TS ~20g100 –1 from cows and buffaloes milks. It was also made from difiltered and direct acidified retentates to reduce the calcium content in the retentate to achieve objective the firmness of the curd. The fresh cheeses were analyzed when fresh and after storage for one month at ~5°C for chemical, physical, rheological and organoleptic properties. The obtained results revealed that Mozzarella made from cow milk and its retentates exhibited much better ripening indices and rehological properties cheeses. The UF-tech-nique lowered the moisture content, lactose, ripening indices, meltability and oilling off in the resultant cheese, while it elevated protein content and yield. Diafiltration processe decreased Ca ++ , P ++ , lactose, ripening indices, while its effect on rehological properties was low. Acidification process either to the normal milk or to the retentats decreased Ca ++ , P ++ , lactose, ripening indices and meltabilty of the produced cheese. Storage increased all constituents in all treatments except lactose and improved the meltability and oilling off. Sensory evaluation revealed that the Mozza-rella cheese from UF-cows' retentate was the best treatment and similar to that from traditional one, while the cheese made from buffaloes' milk had some defects.
El queso es empleado como ingrediente en la preparación de una amplia gama de platos de cocina en el hogar o sectores de catering y comidas preparadas en el sector industrial. Dependiendo de cómo se empleará un queso como ingrediente en un alimento, éste debe cumplir ciertas funciones, lo que da origen a las propiedades funcionales o de funcionalidad (PF), por ejemplo, en el caso de la manufactura de sándwiches o hamburguesas se requiere queso en tajadas, lo que implica una operación posterior al moldeo, que es el tajado de los bloques de queso, pero este tajado debe proveer tajadas de un mismo grosor, por lo que el queso debe tener un grado de firmeza que permitan que el equipo de tajado realice cortes perfectos, que el queso no se desintegre o aglomere al momento de tajar, y que al ser colocadas en el alimento no pierdan su integridad, esta propiedad funcional es conocida como ―tajabilidad‖ (Sliceability). Así han surgido en los últimos años diversas propiedades funcionales de acuerdo a las expectativas que los consumidores tienen en el producto. En este documento se presenta una revisión bibliográfica de algunas de las principales PF de los quesos y se hace un especial énfasis en los de pasta hilada. Se presenta la definición y se indica la metodología para realizar la evaluación de algunas de ellas.
This chapter describes the pasta-filata cheeses that are a diverse group that originated primarily in the greater northern Mediterranean region, encompassing Italy, Greece, the Balkans, Turkey, and Eastern Europe. Cheese, used as an ingredient in prepared food, must satisfy certain performance requirements, determined by the function of the cheese in the particular food application, in which it is used. The level of casein-associated calcium in the newly made cheese also plays a critical role in the initial structure and function of the cheese, as demonstrated by several recent studies, in which different strategies to vary casein-associated calcium were used. Conventional or UF Kashkaval made using fermentation chymosin is not significantly different from that made using calf rennet, confirming numerous published data that recombinant chymosin is a satisfactory alternative to calf rennet in cheese manufacture.
The influence of the fat content, pH, the ripening degree and the incorporation of whey proteins, by two different methods, on the meltability of Cremoso Argentino cheese was examined. Different experimental cheeses were made at pilot plant scale and their meltabilities were determined by a modified Schreiber test. Ripening degree and fat content showed a good correlation with the meltability. Though, cheeses with incorporation of whey proteins showed poor meltability, despite their yields increased. No correlation was found between pH and meltability inside the pH working range studied.
Four treatments of Cheddar cheese with two levels (high and low) of calcium (Ca) and phosphorus (P), and two levels (high and low) of residual lactose were manufactured. Each treatment was subsequently split prior to the salting step of cheese manufacturing process and salted at two levels (high and low) for a total of eight treatments. After two months of ripening, each treatment of Cheddar cheese was used to manufacture process cheese using a twin-screw Blentech process cheese cooker. NFDM, butter oil, trisodium citrate (emulsifying salt), and water were added along with Cheddar cheese for process cheese formulation. All process cheese food formulations were balanced for moisture (43.5%), fat (25%), and salt (2%), respectively. Dynamic rheological characteristics (G′ and G″) of process cheese were determined at 1.5Hz frequency and 750 Pa stress level by using a Viscoanalyzer during heating and cooling, temperature ranges from 30°C to 70°C then back to 30°C. High Ca and P content, and high S/M (HHH and HLH) cheeses had the significantly higher elastic (G′) and viscous (G″) modulus than other cheeses during heating from 30°C to 70°C, and cooling from 70°C to 30°C. No significant difference was observed among the other process cheeses during heating and cooling. Viscoelastic properties of process cheeses were also determined in terms of transition temperature (where G′ = G″), and tan δ during heating (30°C to 70°C). Cheeses with high Ca and P, high lactose, and high S/M content had higher transition temperature than low Ca and P, low lactose, and low S/M content process cheeses. Low Ca and P and low S/M content cheeses (LLL, LHH, LHL, HLL) exhibited more viscous characteristics than high Ca and P and high S/M content process cheeses (HHL, HLH, LLH, HHH) during heating from 30°C to 70°C. Low Ca and P, low lactose, low S/M content (LLL) process cheese was observed for highest tan δ values (0.39 to 1.43), whereas high Ca and P, high lactose, high S/M content process (HHH) had the least (0.33 to 1.06) during heating. This study demonstrates that different characteristics of natural cheese used in process cheese manufacturing have significant impact on process cheese rheological and viscoelastic properties.
The key innovation that was to define the commodity cheese making industry, not only in NZ but worldwide for decades to come occurred from 1960 onwards when the essentially manual cheesemaking industry was mechanised and automated. Driven by, the need to reduce cost, increase scale and reduce labour inputs and the need for greater product uniformity and consistency, the cheese making process underwent significant change with respect to the equipment and processes used. Those changes maximised milk processing capacity and minimised labour input while maintaining, and in many cases enhancing, product quality. As a consequence of this revolutionary approach to cheese making, cheese plants in NZ became larger and fewer and the companies that operated them amalgamated. While the last 40 years has not seen the same magnitude of change in technology that defined the mechanization of the cheese making process in the proceeding decade before 1970, continued innovation has seen significant refinements in the way cheese is made by the mechanized process that has led to further reductions in cost, increased scale efficiencies, greater product uniformity and consistency and fewer labour units being required. Recent published literature and patent applications would suggest that the next innovative steps in the evolution of cheese making in the 21 st century will be the development of completely new ways of making cheese together with the continued refinement of the traditional processes that we have seen to date.
Mozzarella cheeses were made with a single culture (SC) or a mixed culture (MC) using 1x or 6x of cheese coagulants chymosin or Cryphonectria parasitica (CP). Melt area increased only by approximately 80% in cheeses made with SC against 230% in the cheeses made with MC after 30 d of storage. Soluble nitrogen was also higher in MC cheeses as compared to SC cheeses. Both the elastic (G’) and the viscous (G”) modulus decreased with storage. Decrease in both moduli was greater in the MC cheeses at 6× enzyme level compared to SC cheeses at 1× enzyme level. The synergism between coagulating enzyme and starter culture was beneficial, which improved melt and flow of Mozzarella cheese and had profound effects on the viscoelastic properties of Mozzarella cheese.
Based on our studies, the most important parameter controlling melting of mozzarella cheese is the status of the protein matrix. Fat is important in allowing moisture to be retained in cheese and also has a protective and lubricating effect as the cheese is heated, but it should be looked upon as a secondary factor because if the pH, moisture, calcium and salt content of the cheese is appropriate, then even a fat-free cheese can be manufactured so as to have extensive melting properties. During the pasta filata stage of manufacturing mozzarella cheese, the proteins are aligned into fibres separated by channels containing close-packed fat globules, bacterial cells and whey serum. During storage of the cheese, the serum in these channels is absorbed as a function of increased hydration of the proteins in the surrounding matrix. Then, as the proteins become more hydrated (and correspondingly less aggregated), the meltablity of the cheese increases. This increased interaction of the caseins is enhanced by the addition of NaCI to the cheese and reducing cheese calcium content.
There is mounting evidence that the structure and function of mozzarella cheese are influenced by physico-chemical changes that occur during the first weeks after manufacture. Analyses of the expressible serum obtained from mozzarella cheese by high-speed centrifugation show that intact caseins (αs1-, αs2-, β-, para-κ-) and casein-associated minerals (Ca, Mg, Zn) become more soluble during ageing, with an accompanying increase in the water-holding capacity of the cheese. This behaviour is salt-dependent and may be indicative of salt-induced solvation and swelling of the casein fibres that form the structural matrix of the cheese. The distribution of casein-associated minerals between the protein matrix and the serum phase is influenced by cheese pH, with lower pH favouring greater solubility. Soluble calcium is of particular interest, because it strongly inhibits salt-induced solvation of casein and does not contribute to cheese structure.
Apparent viscosity, free oil formation, and meltability were used to assess the effects of aging time (6 to 21 d at 4°C), ripening before or after freezing, freezing rate, and frozen storage (3 mo at –20°C) on characteristics of low moisture Mozzarella cheese. The results obtained were compared with unfrozen control samples, aged at 4°C between 6 and 42 d. When the final product was aged from 14 to 21 d at 4°C before consumption, low moisture Mozzarella cheese could be frozen and then store at –20°C without loss of quality.
The effects of homogenization of cheese milk and proteolysis in cheese on formation and thermal properties of free oil in Mozzarella cheese were examined. The amount of free oil generated by heating Mozzarella depended on interactions between casein and fat. Homogenization of cheese milk greatly reduced free oil; homogenization of skim milk alone had no effect. When the milk was not homogenized, free oil formation increased with the percentage of fat in DM and protein breakdown. Thermal profiles of cheese fat, free oil, and milk fat were similar, although cheese fat melted at a higher temperature, and free oil from homogenized Mozzarella melted at a lower temperature. Heat of fusion and fatty acid composition of free oil were not different from those of cheese fat.
An understanding of the seasonal and regional variation of the physical and chemical properties of milkfat is important to the dairy and food industries for optimal product manufacture and selection of milkfats for markets and applications. However, recent information on such variations over a period of time within and among Australian regions is not readily available to the Australian dairy industry and their customers. The national Australian milkfat survey was implemented to provide up to date comprehensive data on the composition and properties of milkfat. The survey involved the participation of 20 regional manufacturing sites across six states, over a two-year period. Analysis of the milkfat included Dropping Point and % Solid Fat Content by pulsed nuclear magnetic resonance. Dropping points among states and seasons varied by up to 5°C and highlighted that there are very significant differences among states. The solid fat content was also highly variable among states and sites. The variations ranged from as much as 18% solid fat to as little as 6% solid fat at 5°C over the survey period. It is envisaged that these data will assist the Australian dairy industry to better understand, predict and manage the seasonal and regional variations of the milkfat properties and thereby enhance the functionality and marketability of milkfat-based products.
An empirical, easy-to-use, tensile method for the objective quantification of stretch of molten cheese was developed. Shredded cheese was distributed uniformly, at a fixed loading (0.25 g/cm2), on to a pizza base, pre-cut in half. After cooking in a thermostatically controlled electric fan oven at 280 °C for 4 min, the pizza pie was placed on the platform unit of the stretch apparatus. The platform unit consisted of fixed and rolling elements. Before stretching, the pizza pie was clamped (one half to the fixed element and the other half to the rolling element). The rolling element was then drawn along the rail system at a fixed speed, resulting in stretching of the molten cheese mass until complete failure of the extended string(s)/sheet connecting both halves of the pizza base. Stretch was defined as the distance travelled by the mobile element to the point of complete strand breakage. The stretch values obtained for low-moisture Mozzarella of different ages were influenced by cheese load and holding time before stretching of the cooked pizza pie, but were independent of stretching speed in the range 0.033–0.100 m/s. The Stretchability of low-moisture Mozzarella cheese (2–17 weeks old) was greater than that of Cheddar cheese (2–25 weeks old). Analogue pizza-type cheeses, with compositions similar to that of low-moisture Mozzarella cheese, showed large inter-product variation in stretchability and generally had inferior stretch compared with low-moisture Mozzarella cheese.
The objective of this study was to evaluate various properties of low browning Mozzarella cheese. Low moisture, part skim type Mozzarella cheese was made using strains of Streptococcus spp. and Lactobacillus helveticus that release inappreciable amounts of galactose into the cheese curd and was compared with high browning cheese made using cultures that release galactose into the curd. Cheese composition differed only for galactose content. The browning potentials of the cheeses were significantly different. Pizzas were made using 125 g of each cheese type and evaluated for appearance, texture, and flavor by a consumer panel. Panelists could distinguish between pizza samples based on color of the baked pizza, although no differences or preferences based on any of the other criteria were discernible. Both brown and low browned pizza were acceptable by the panelists, indicating that browning of Mozzarella cheese on pizza was not an undesirable property.
Commercially manufactured low moisture, part-skim Mozzarella cheese (2.25-kg loaves) was either shredded or cut into 5- × 10- × 7-cm blocks. Shredded cheese and blocks were either frozen at –196°C and stored at –70°C or frozen and stored at –20°C. Cheese was then thawed at either 4.4, 12.8, or 25°C. Samples were analyzed for stretch by helical viscometry, for melt by the modified tube test, and for cook color by reflectance colorimetry just prior to freezing and at 7, 14, 21, and 42 d of storage. Mozzarella cheese stored at 4.4°C was used as the control. Shredding, freeze temperature, thaw temperature, and time of storage had no effect on cook color. Frozen cheese showed greater stretch than unfrozen cheese. Shredded cheese stretched more after frozen storage than unshredded cheese. Frozen shredded cheese melted less than frozen unshredded cheese. Cheese frozen at –20°C melted more after frozen storage than cheese frozen at –196°C. Cheese stored at 4.4°C melted more than frozen cheese. Thawing temperature by itself had no effect on either stretch or melt. Stretch was greatest in Mozzarella cheese frozen at –196°C, shredded, and held for at least 21 d. Melt was greatest in cheese in blocks, frozen at –20°C, and stored for only a short time.
Mozzarella cheese was made by acidifying milk containing 2% fat with phosphoric, acetic, hydrochloric, malic, or citric acids to pH of 5.6, 5.4, or 5.2 before rennet coagulation and processing of the curd. Moisture content, mineral retention, and rheological properties of cheese were affected significantly by the type of acid and pH at coagulation. Direct relationships existed between calcium, phosphate, viscosity, and modulus of elasticity. Relationships were inverse between moisture content of cheese, meltability, and other factors mentioned above. Cheese was mild in flavor, but bitterness was in high-moisture cheese made at low pH.
ABSTRACT The objective of this study was,to determine,the impact of coagulant type and,refrigerated storage on,functional properties of unmelted,and melted Moz- zarella cheese. A “no-brine” Mozzarella cheese-making method,was used to pro- duce cheese with homogeneous,chemi- cal composition. Cultured Mozzarella cheeses were made,with three different coagulants (Endothia parasitica protease, chymosin derived by fermentation, and Mucor miehei protease) in 1 d, and cheese,making,was,replicated on 3 different d. During 50 d of storage at 4‘C, texture profile analysis parameters (hardness, cohesiveness, and springiness) of unmelted cheese decreased, meltabil- ity increased, apparent viscosity of melted cheese decreased, and free oil formation from melted cheese increased. Overall, the Mozzarella cheese made us- ingfree oil release on melting than other cheese. In general, cheeses made with chymosin,and Mucor miehei pro- tease were similar in functional charac-
The effect of high pressure homogenization on the milk fat globule membrane proteins was investigated. Milk with 1.5 or 3.0% milk fat was heated in vats at low or high temperature (65°C for 30 min or 85°C for 20 min), homogenized, cooled, and centrifuged to separate the cream and serum phases. The amount of protein load per surface area increased as homogeni- zation pressure increased but decreased with heat treatment. The composition of the proteins forming the milk fat globule membrane in homogenized milk was not affected by homogenization pressure or fat concentration, but significant differences in the com- position of the milk fat globule membrane were caused by the heat treatment that was applied before homogenization. The milk fat globule membrane pro- teins in homogenized milk were composed of native membrane proteins, caseins, a-lactalbumin, and b- lactoglobulin. Caseins represented about 70% of the proteins in the milk fat globule membrane. In milk heated at 85°C for 20 min, the ratios of adsorbed a- lactalbumin and b-lactoglobulin relative to adsorbed caseins were higher than in milk heated to 65°C.
Changes in the water-holding capacity of low moisture Mozzarella cheese during aging were evaluated by measuring the amount of serum expressed from the cheese upon centrifugation at 12,500 × g for 75 min at 25°C. Low moisture Mozzarella cheeses (n = 3) were obtained the day after commercial manufacture and stored at 4°C. Expressible serum was obtained at 2, 4, 8, 12, and 16 d after manufacture; analyzed for concentrations of CP and protein that was soluble at pH 4.6, Ca, P, K, Mg, Na, and Zn; and evaluated for proteins and peptides by urea-PAGE. Quantity of expressible serum decreased dramatically during storage, indicating substantial increase in water-holding capacity. Both CP and protein that was soluble at pH 4.6 in expressible serum increased during storage; however, CP content was higher and increased faster than protein that was soluble at pH 4.6. Urea-PAGE confirmed that unhydrolyzed αs1-, αs2-, and especially β-CN accounted for a large share of the CP in the expressible serum. Concentration of Zn increased during aging, unlike that of other elements. A model that is based on the swelling and solubilizing action of NaCl on the protein matrix is proposed to account for the increases in water-holding capacity and the unhydrolyzed caseins in the water phase of Mozzarella cheese during aging.
Nonfat Mozzarella cheese curd was manufactured in 227-kg batches on 3 separate d using direct acidification. Cheeses with differing NaCl concentrations were obtained by dividing curd into separate lots that received various applications of dry NaCl (0, 0.5, and 1.0% NaCl, wt/wt) and hot brine (0, 5, and 10% NaCl, wt/vol) stretching treatments. The NaCl, Ca, ash, fat, moisture, and protein contents as well as cheese meltability and expressible serum of each cheese were determined. In addition, observations were made on cheese color and functionality over 24 d of storage at 4̊C. Transmission and scanning electron micrographs of unsalted and salted cheeses were evaluated to determine the differences in the protein matrix. The type of NaCl application and the NaCl content of the cheeses influenced the cheese moisture, meltability, expressible serum, microstructure, and ultrastructure. The moisture content was highest in cheeses in which the curd was salted before stretching. The melt was the lowest in cheeses that were unsalted. Cheeses that were stretched in either 5 or 10% brine had <1% of the amount of expressible serum observed in unsalted cheese. Unsalted cheeses had a more open structure than did salted cheeses. Pockets of free serum were distributed throughout the protein matrix of the unsalted cheese, thus producing light-scattering surfaces and making the cheese opaque. In contrast, the salted cheeses had a more homogeneous protein matrix that lacked light-scattering surfaces, resulting in a translucent cheese. Neither NaCl concentration nor method of salting affected.the Ca content of the cheeses.
Exopolysaccharide-producing starter cultures, consisting of single strains of Streptococcus thermophilus MR-1C and Lactobacillus delbrueckii ssp. bulgaricus MR-1R, were used to make three trials of low fat (6% fat) Mozzarella cheese. Our aim was to determine whether observations made using small [10-kg (22-lb) capacity] vats with manual stretching of curd could be replicated using pilot-scale [454-kg (1000-lb) capacity] double-O vats with mechanical stirring and stretching of the curd. A control cheese was made using S. thermophilus TA061 and Lactobacillus helveticus LH100 as starter cultures that did not produce exopolysaccharides. Cheese was measured for moisture content and meltability at d 1. Cheese made with the exopolysaccharide-producing starter cultures had 2% higher moisture contents and exhibited slightly higher meltability. Because of changes in the procedure to manufacture low fat cheese that were necessary when the mechanized vats were used, the cheeses made in the double-O vats were slightly lower in moisture than cheeses previously made in the hand-stirred laboratory-scale vats.
Low fat Mozzarella cheese was made from milks containing casein to fat ratios of 3.0, 5.0, 7.0, and 8.0. Prior to addition of rennet, milk was pasteurized at 79°C for 28 s and then acidified to pH 6.0 with lactic acid. Three replicates of each cheese were made in 7-L vats and stored at 4°C. Functional properties as pizza cheese were evaluated. Cheese moisture and fat contents were evaluated at 1 d. Apparent viscosity and extent of flow of melted cheese, cook color, and proteolysis were evaluated at 1, 7, 14, and 28 d. Moisture content measured by a rapid microwave oven method underestimated the moisture content of low fat cheeses; probable moisture was calculated by component analysis. The part-skim Mozzarella control with 19% fat had a moisture content of 51%; the moisture contents of the low fat cheeses containing 2 to 5% fat were 63%. Low fat cheeses did not melt as well as did the part-skim Mozzarella cheese, although the differences between the cheeses with 2 and 5% fat were insignificant. Storage for 28 d only marginally increased the meltability of low fat cheese. Lower fat content also increased cook color. The amount of intact αs-CN decreased by at least 48% in all cheeses as a result of proteolysis during 28 d of storage.
Cultured low moisture, part skim Mozzarella cheeses were produced using the same milk (185 kg per vat), starter, and coagulant, but with two different whey pH at draining (6.40 and 6.15). Cheese was made by the milled-curd, no-brine method with a 41°C cooking temperature, 5.25 pH at milling, and 57°C stretching temperature. Cheese making was repeated three times on 3 different d. As pH decreased at draining, calcium content in the cheese was lower (from .83 to .75%), and cheese moisture was slightly higher (from 45.7 to 46.3%). However, no significant differences were detected in protein, fat, and salt contents. During storage, soluble nitrogen contents, meltability, and free oil increased, but αs-casein and apparent viscosity decreased, for all cheeses. There were significant influences of the interaction of draining pH with storage time on 12% TCA-soluble nitrogen content; i.e., proteolysis during refrigerated storage was faster with lower pH at draining.
The impact of the rod:coccus ratio on chemical composition, proteolysis, and functional properties of Mozzarella during storage was determined. Three vats of cheese were made in 1 d using three rod:coccus ratios (9:1, 5:5, and 1:9). Cheese making was replicated on 3 different d using a 3 × 3 Latin square design. Changes in titratable acidity and pH during cheese making were slower with the 9:1 rod:coccus ratio. The viable count of both microorganisms increased during cheese making, but cocci were the dominant organism in the curd at milling, regardless of the initial rod:coccus ratio. Cocci remained viable during stretching at 57°C and during storage at 4°C. The rod:coccus ratio did not affect the initial composition of cheese. However, proteolysis of cheese, especially development of N that is soluble in 12% TCA, was faster with 9:1 rod:coccus ratio during storage. Hardness and cohesiveness of unmelted cheese, meltability, and free oil formation were unaffected, but springiness and apparent viscosity were lower with the 9:1 rod:coccus ratio. The amount of inoculation may have more impact on the functional properties of Mozzarella cheese than the rod:coccus ratio.
Low fat (6%) Mozzarella cheese was made in 10-L vats using an exopolysaccharide-producing starter culture consisting of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. A control cheese was made using strains of S. thermophilus and Lactobacillus helveticus that did not produce exopolysaccharide. Both starter cultures were also used with the addition of a mesophilic exopolysaccharide-producing adjunct culture consisting of Lactococcus lactis ssp. lactis and L. lactis ssp. cremoris strains. Moisture content of the cheese was measured at d 1, and melt was measured at 1, 7, 14, and 28 d of storage at 4°C. Analysis of variance showed significant differences in moisture and melting properties between cheeses made with or without exopolysaccharide-producing starter cultures. Cheeses made with the addition of the adjunct culture showed significant differences in moisture, but not in melting properties. The moisture content of cheeses made with both the exopolysaccharide-producing starter and the adjunct cultures increased 4%, and the use of the exopolysaccharide-producing starter cultures alone increased moisture content 3% over that of the control cheese. Melt also increased in cheeses as moisture content increased.
The objectives of this study were to isolate galactose-fermenting, galactose-nonreleasing strains of Streptococcus and Lactobacillus and to use these strains as starter cultures in the manufacture of low browning Mozzarella cheese. Four Streptococcus isolates having the desirable phenotype, combined with a Lactobacillus helveticus strain, were acceptable as starter cultures based on activity tests. Fifteen vats of Mozzarella cheese were produced, in triplicate, representing four experimental treatments (made with galactose-nonreleasing strains) and one control (made with a galactose-fermenting, galactose-releasing Streptococcus). Analyses were performed on cheese after 5 and 28 d of refrigerated storage. The lactose and galactose content of cheese remained constant or decreased over the 28-d testing period for all experimental treatments. The galactose content in the control cheese increased over the testing period and was significantly higher by d 28 than in the test cheeses. Browning was greatest on d 28 and at the more severe baking conditions. Control cheese browned more than experimental cheeses did. Melt behavior and free oil formation were generally not affected by treatment. The results indicated that the galactose-fermenting, galactose-nonreleasing strains could be used to make low browning Mozzarella cheese.
Mozzarella cheese was manufactured to contain up to 50% less fat than conventional part-skim Mozzarella cheese. Milk, which had been standardized to a casein to fat ratio of 1.2, 1.6, 2.0, or 2.4, was inoculated with single strains of Lactobacillus helveticus and Streptococcus salivarius ssp. thermophilus. A new manufacturing procedure was used to retain moisture in the cheese as fat percentages decreased and protein increased. Stretch, melt, and cook color were evaluated at 1, 7, 14, and 28 d during storage at 4°C. Analysis of variance showed no significant differences in stretch, melt, or cook color between cheeses with different casein to fat ratios. Cheese made with a casein to fat ratio of 2.4 retained more stretch over 28 d than did cheese with lower casein to fat ratios. Stretch decreased and melt increased significantly for all cheeses during storage for 28 d. The stretch and melt characteristics of Mozzarella cheese containing up to 50% less fat were similar to the part-skim Mozzarella reference cheese.
The effect of mixer screw speed and barrel temperature on the length of the filled section in the mixer, melt exit temperature, specific mechanical energy, and viscoelastic properties were determined for low moisture, part-skim Mozzarella cheese. Three vats of cheese were made in 1 d using three different mixer screw speeds (19, 12, and 5 rpm) and three different barrel temperatures (57, 66, and 74°C). For each screw speed (at constant barrel temperature), the horsepower increased almost linearly as the length of the filled section increased. The linearity of the relationship between horsepower and filled length decreased substantially as the barrel temperature (at constant screw speed) increased. The effect of thermomechanical treatment on the rheological properties of the cheeses was determined by plotting the initial modulus in stress relaxation versus cheese exit temperature and specific mechanical energy. This systems approach indicated that the highest moduli were obtained at the highest cheese exit temperatures, which were associated with the lowest specific mechanical energy values. Thus, low shear stresses in the stretcher-cooker seem to promote development of a more extensive elastic network in the cheese.
Brine-salted Mozzarella cheese sometimes develops a soft, wet surface during storage, and the objective of this study was to compare distributions of salt and moisture in two surface types of cheese blocks. Seven 9.1-kg blocks of Mozzarella with soft, wet surfaces and 5 9.1-kg blocks with firm, dry surfaces were obtained from five different cheese companies. Moisture and salt distributions were determined using a sampling plan that provided three concentric samples at different depths within each of three cross-sectional slices from the end of the block and three slices from the middle. Salt distributions in cheeses with soft, wet surfaces were similar to those in cheese with firm, dry surfaces; salt content increased from center to surface and was higher at the ends of the block. In contrast, moisture distribution differed markedly. The moisture content decreased from center to surface in blocks with firm, dry surfaces, but the pattern was the reverse in blocks with soft, wet surfaces, which also had higher moisture contents at the ends of the block. The data are consistent with the hypothesis that the temperature differential, which develops during exposure of the warm cheese to cold brine and then dissipates slowly during postbrine cooling, is important in the development of soft surface defect.
To eliminate the problems associated with brine salting, a milled curd, no brine method for making low moisture, part-skim Mozzarella cheese was developed and reported previously. The method produced cheese with homogeneous chemical composition and desirable functional characteristics. However, the moisture content of the low moisture, part-skim Mozzarella cheese from this method was too low (about 44 to 45%). To increase cheese moisture content, a stirred curd, no brine Mozzarella cheese-making process was developed. With this new method, cheese moisture content can be controlled within the range of 45 to 52% while achieving normal salt, pH, and fat content on a dry weight basis. Changes in proteolysis and functional properties during the refrigerated storage were similar to those for commercial cheeses.
Objectives of this research were to determine whether locational differences in composition within a cheese block affected melting characteristics. Immediately after brining, industrial low moisture and low moisture, part skim cheeses were divided in half vertically. Equally weighted samples representing surface and center from one-half of each block were analyzed immediately (d 2) for apparent viscosity, free oil, and composition (moisture, fat, NaCl, Ca, pH). Samples from the other half were vacuum packaged and stored at 4°C until analysis on d 16. From d 2 to d 16, free oil increased significantly, and apparent viscosity decreased significantly. Free oil increased the most in the center of low moisture cheeses, indicating that Mozzarella with high fat and low NaCl contents has greater tendency to oil off. Surface samples had significantly higher NaCl and apparent viscosity and lower moisture, Ca, and free oil than center samples. These locational differences in melting characteristics may be caused in part by exchange of Na with casein-bound Ca at the cheese surface, which enhances the emulsifying ability of soluble casein, resulting in a more emulsified fat phase at the cheese surface and less formation of free oil.
Direct acid Mozzarella cheese was made in 6-L vats using calf chymosin, bovine pepsin, porcine pepsin, or Mucor miehei protease. Four cheeses were made with each enzyme. Stretch, melt, cook color (reflectance colorimeter), moisture, and pH were measured at 1, 7, 14, and 28 d. Correlation coefficients among these parameters were calculated, and the effects of choice of enzyme and storage time at 4°C on these parameters were evaluated by analysis of variance. Cook color was not affected by enzyme type and changed only slightly during storage. Melt was affected by choice of enzyme and increased significantly with time. During the 28-d ripening period, the melt of cheese made with calf chymosin increased the most. The smallest increase in melt was in cheese made with porcine pepsin. Stretch was significantly affected by enzyme and by storage time. Stretch decreased rapidly in all cheeses between d 1 and 7 and stabilized during the next 21 d. Cheese made with porcine pepsin had the greatest stretch, and cheese made with calf chymosin had the least stretch, between d 7 and 28. Melt increased, and stretch decreased, during storage of all cheeses. The type of milk-clotting enzyme used played a significant role in determining physical properties of direct acid Mozzarella cheese.
A method that employs helical viscometry to evaluate the melting behavior of Mozzarella cheese was reported earlier. During analyses of numerous Mozzarella cheeses of varied age and composition, it was observed that some cheeses form a natural layer of free oil at the sample surface, but others do not. It was thought that free oil accumulation might cause variation in the measurement of apparent viscosity. Therefore, experiments were conducted to determine whether addition of exogenous butter oil could reduce analytical error by minimizing the differences in sample surface conditions. Effects of cheese age (2 or 21 d), cheese type (low moisture or low moisture part skim), and butter oil addition (0, 25, or 100 ml at 60°C) on sample temperature uniformity during analysis and apparent viscosity were evaluated. Added butter oil significantly reduced surface cooling and apparent viscosity in 2-d-old but not in 21-d-old cheeses. Surface cooling and desiccation in 21-d-old cheeses were minimized by the formation of natural free oil, which negated the effect of added butter oil. Adding exogenous butter oil effectively standardized the surface conditions of samples that oiled off to varying degrees, resulting in better analytical performance. Repeatability of the test with added butter oil (25 ml) was evaluated.
The melting characteristics and functional stability of imitation and natural commercial Mozzarella cheeses were investigated. Five brands of commercial casein-based imitation Mozzarella cheese (three to five samples per brand) were randomly assessed for apparent viscosity and free oil formation. Average apparent viscosity among brands ranged from 9.5 ± 1.8 to 28.3 ± 14.5%; average free oil ranged from 4.3 ± 1.9 to 7.9 ± 1.3%. Apparent viscosity and free oil were also measured weekly in five different samples of imitation Mozzarella (three different brands) during 3 to 4 wk of storage at 4°C. Stored imitation cheeses showed a high degree of functional stability with comparatively little change in apparent viscosity or free oil. In contrast, natural low moisture part skim Mozzarella cheeses (n = 8) underwent large changes in apparent viscosity and free oil during 4 wk of storage at 4°C. Apparent viscosity decreased from 111 ± 22 to 27 ± 6% in the first 14 d after manufacture; free oil increased from 5.9 ± .6 to 8.4 ± .9%. These data indicate that casein-based imitation Mozzarella cheeses examined were functionally analogous to 2- to 4-wk-old (apparent viscosity) and 0- to 2-wk-old (free oil) natural low moisture part skim Mozzarella cheese and were functionally more stable during refrigerated storage. Such stability makes analogs very attractive to the food processing and service industries. Analogs may make substantial inroads into the Mozzarella market in the future if certain labeling constraints, which presently limit their acceptance, are overcome.
On four occasions, a 2.72-kg (6-lb) rectangular block of commercial Mozzarella cheese was obtained immediately after manufacture and brined (27% NaCl wt/wt, Ph 5.3) in the laboratory for 4 h at 4°C. After brining, four concentric sections (1 = 0 to 1 cm from surface, 2 = 1 to 2 cm, 3 = 2 to 3 cm, and 4 = core) were taken from half the block and analyzed for NaCl, moisture, and proteolysis. The other half was vacuum packaged and aged at 4°C for 14 d prior to sectioning and analysis. Average NaCl concentrations in fresh cheese (1 d after manufacture) were highest (2.28 ± .28%) in section 1 and decreased sharply to <.3% in sections 2, 3, and 4 but became linear after 14 d of aging. Moisture concentrations in the fresh cheese (1 d) were lowest in the core (49.06 ± 1.77%) and outermost sections (49.41 ± 2.56%), highest in section 2 (52.22 ± 2.86%), and intermediate in section 3 (50.43 ± 1.95%). However, after 14 d, cheeses did not have a similar pattern of moisture distribution, and no significant differences were found among sections within cheeses. Electrophoretograms of the cheeses showed a breakdown of αs1-casein to αs1-I-peptide, suggesting residual coagulant activity. Also the intensity of the band corresponding to β-casein decreased with concomitant increase in γ-casein bands, suggesting plasmin activity. Other unidentified bands with electrophoretic mobility slower than γ-caseins were noted. Between d 1 and 14 postmanufacture, αs1-casein and β-casein decreased by 26.4 ± 10.1% and 40.2 ± 9.0%. Levels of total N soluble in water increased from 4.07 ± 1.10% in fresh cheese to 9.66 ± 1.61% in 14-d-old cheese.
Six-liter vats of Mozzarella cheese were made using either single strains of Lactobacillus helveticus or paired strains of L. helveticus and Streptococcus salivarius ssp. thermophilus. Lactobacillus helveticus strains were either strongly or weakly proteolytic as established by the o-phthaldialdehyde test. Three cheeses were made with each culture type and stored at 4°C. Stretch, melt, color, moisture, and pH values were determined at l, 7, 14, and 28 d. All cheeses lost stretch rapidly from d 1 to 7 and slowly declined between d 7 and 28. Melt increased rapidly for all cheeses from d 1 to 7 and then remained constant. Differences in stretch and melt from one culture type to another were not significant. Cheese made with proteinase-deficient strains had more stretch after holding for 14 and 28 d than cheese made with nondeficient strains. Time of storage significantly affected both stretch and melt over 28 d. Cheeses made from all four culture types decreased in cook color over 28 d of storage. There were no significant strain differences in cook color, but the culture by time interaction was significant. Cheese made with pairs or single strains of L. helveticus had the same melt, more strech, and less cook color than cheese made with paired strains of Lactobacillus delbrueckii ssp. bulgaricus and S. salivarius ssp. thermophilus studied previously.
A test for free oil in melted Mozzarella cheese using standard Babcock equipment was developed and evaluated. Eighteen grams of whole milk or part skim Mozzarella were weighed into 50 or 20% Paley-Babcock bottles, respectively. Bottles were immersed in boiling water for 4.0 min to melt cheese. Distilled water (20 ml at 57.5°C) was then added and the bottles were centrifuged hot (ca. 57.5°C) for 10 min. A portion of 1:1 distilled water:methanol (21°C) was added to a final level in the upper region of the calibrated neck and then centrifuged for 2 min. Bottles were then rocked by hand for 10 s, centrifuged for 2 min, and a second time rocked by hand for 10 s and centrifuged for 2 min. Finally, bottles were tempered in 57.5°C water for 5 min and the fat column then measured with glymol. This procedure gave a clear, defined fat column. Free oil was expressed as percentage in cheese and percentage in cheese fat. A series of recovery trials in which low moisture and low moisture, part skim Mozzarellas were spiked with butter oil gave recoveries ranging from 97.3% to 104.5%. Eighteen replicates of a low moisture and low moisture, part skim Mozzarella gave coefficients of variation of 3.3 and 6.2%, respectively.Free oil was measured in 64 Mozzarella cheese obtained from local supermarkets and two industrial cheese plants. Free oil as a percentage of total cheese fat ranged from 8.8 to 84.9%. Free oil increased with increasing cheese fat on a dry basis.
Differential scanning calorimetry was used to distinguish natural Mozzarella cheese from imitation Mozzarella made with calcium caseinate. The enthalpy of the milk fat melting transition at 18°C decreased with increasing caseinate concentration. Scanning electron microscopy studies revealed an agglomeration of lipids in the imitation samples, whereas the natural cheese had a uniform dispersion of fat globules. The addition of the caseinate apparently affected the crystallization of the fat, leading to the enthalpy reduction. Electrophoresis and atomic absorption procedures did not differentiate between natural and imitation samples.
Mozzarella cheese from two cheese plants (A and B) was collected biweekly for 10 wk. Five vats of cheese were sampled from a day's production. Cheeses were vacuum packaged and held at 4°C for 12 d. On d 12, cheeses were analyzed for composition (fat, total solids, calcium, salt) and apparent viscosity (a measure of cheese melting properties) by helical viscometry. Two cheeses from each plant also were held vacuum packaged at 4°C for 1 mo and analyzed weekly for apparent viscosity. During the survey period, plant A reported severe starter problems attributed to bacteriophage; plant B reported no problems in manufacture.Plant A experienced greater vat-to-vat and week-to-week variation in cheese composition and apparent viscosity than plant B. Cheese composition had a profound impact on Mozzarella melting properties. Cheeses stored at 4°C for 1 mo showed large initial differences in apparent viscosity but a common pattern of progressive decrease in apparent viscosity over time. Mozzarella functionality developed in two distinct but interrelated phases. The first phase occurred during manufacture when basic curd structure was established. A second phase occurred during storage when functionality and curd structure were altered. Helical viscometry offers new opportunities for the study of Mozzarella melting properties.