Fresh White Cheeses from Buttermilk with Polymerized Whey Protein: Texture, Color, Gloss, Cheese Yield, and Peptonization

: Buttermilk and whey, despite their documented health and technological potential, are still not sufﬁciently utilized for the development of new products. In this research, the texture, color, gloss, cheese yield, and peptonization of fresh white cheeses made from buttermilk with the addition of whey proteins after heat treatment were analyzed. Additionally, the inﬂuence of the polymerization process on cheese yield and composition was examined. Four fresh white cheese samples were prepared: without a whey protein concentrate (FWC); with a whey protein concentrate (FWC/WPC); with single-heated polymerized whey proteins (FWC/SPWP); and with double-heated polymerized whey proteins (FWC/DPWP). The introduction of whey proteins in buttermilk cheese production increased the cheese yield by over 2-fold. There were no differences in color and gloss between the FWC/SPWP and FWC/DPWP samples. The cheese became glassy and transparent during melting. The content of uncrushed curd that remained white ranged from 27% in FWC/DPWP to 74% in FWC/SPWP.


Introduction
Buttermilk and skim milk are characterized by a similar composition in terms of their content of lactose, casein, whey proteins, and minerals [1,2].However, they differ in phospholipid content.Buttermilk contains up to 10 times more phospholipids than skimmed milk [1].The source of phospholipids in buttermilk is the milk fat globule membrane (MFGM), which surrounds and stabilizes the fat globules, which are released during the churning process [3].Hence, buttermilk is classified as a functional food [4], and publications have cited the health benefits of the MFGM, e.g., infection prevention, cognitive improvement and brain system development, immunity and protection metabolism [5], reduction in cholesterol levels, and anticancer [2].
Due to its structure-forming, emulsifying, and water-binding properties, buttermilk is used in the production of yogurts [6][7][8]; ice cream [9,10]; as a component in mixtures for chocolate production [11]; meat marinating [12]; and to improve the flavor and texture of bakery products [13].
The cheesemaking sector is a large part of the dairy industry [14], where innovative concepts for the enhancement of cheese quality are of concern, e.g., the implementation of probiotic bacteria and non-fat cheese production, but also sensory properties.The sensory properties, texture, viscosity, and moisture retention of cheeses can be improved using buttermilk [15] and/or the introduction of whey proteins to its composition [16].During the cheesemaking process, it is common to increase the protein content to increase cheese yield [14,17].In the production of fresh and hard cheese, a high concentration of casein is recommended, while in the production of quark cheese, a high total protein concentration and a high degree of whey protein denaturation is also desirable.The protein's composition can be modulated using membrane processes or the introduction of protein concentrates into the processed milk [18].The texture of cheeses can be affected by moisture, fat content, pH, and, importantly, the structure of the protein matrix [14].The structure of the protein's matrix can be modified, e.g., by conducting the polymerization process of whey proteins induced by heat treatment [19][20][21].The obtained whey protein aggregates are used as a thickening agent for the formulation of fermented milk [22]; for food texture design [23]; for the microencapsulation of Lactobacillus acidophilus, which improves their survivability in yogurts [24]; to increase the water holding capacity and reduce the syneresis of fermented milk [25]; as a fat replacement in the development of low-fat yogurts [26]; and in determining the behavior of water in cheese from buttermilk [16].
Buttermilk and whey are considered the main by-products in the dairy industry and, despite their documented health and technological potential, are still not sufficiently utilized for the development of new products [13].In cheesemaking, milk is primarily employed as the basic raw material, and buttermilk is usually an additive aimed at improving rheological or sensory properties [27,28].The replacement of milk with buttermilk in cheese production can successfully lead to a new product with improved functions and nutritional value [15].
The aim of our research was to directly use buttermilk as a by-product of butter production and indirectly use whey as a whey protein concentrate obtained from buttermilk, allowing for the development of an innovative dairy product: fresh white cheese from buttermilk with polymerized whey proteins.The effect of the heat treatment of whey proteins on the texture, color, and gloss of buttermilk cheese was analyzed for these parameters and its possible further use as a base, e.g., for the production of curd-ripened fried cheese.We also examined how the polymerization process impacted cheese yield and composition, which will provide the necessary knowledge for future cheesemaking.

Fresh White Cheese from Buttermilk Preparation
Buttermilk leftovers were obtained from the industrial production of butter from cream (Great Poland, Poland).The buttermilk contained 0.5% fat, 3.4% protein, and 3.7% lactose.The fresh white cheese from buttermilk was prepared with the addition of whey protein concentrate powder (WPC, 5.62%, w/v) and a whey protein concentrate after the polymerization process (PWP, 28%, w/v).The WPC contained 79.49% proteins, 6.31% fat, 5.15% lactose, 4.81% water, and 1.26% ash.
The WPC dispersion was adjusted to a pH of 7.0 using 0.1 M of sodium hydroxide at 21 • C. Single-heated polymerized whey proteins (SPWP, 28%, w/v) were heated at 85 • C for 30 min and then rapidly cooled to room temperature in ice water under agitation.The solutions were then heated again, keeping exactly the same conditions as used in the first heating process.Further heating at 85 • C for 30 min led to the formation of double-heated polymerized whey proteins (DPWP, 28%, w/v), which were then rapidly cooled to room temperature in ice water under agitation [21].
The buttermilk (20 L) with whey proteins (ratio of 0.23 L of PWP solution for every 1 L of buttermilk) was mixed in a double coat cheese kettle, type SKM50 (Plevnik, Dobrova, Slovenia), with an automatic processor, GPC 145, equipped with an automatic propeller stirrer at 36 rpm and 15 • C for 10 min,.Four fresh white cheese samples from buttermilk were prepared without the addition of the whey protein concentrate (FWC); with the addition of the whey protein concentrate (FWC/WPC); with the addition of single-heated polymerized whey proteins (FWC/SPWP); and with addition of double-heated polymerized whey proteins (FWC/DPWP) (Figure 1).The conditions for processing were selected so that coagulation occurred after 2 h at a temperature of 50-52 • C. The curd was sliced.Draining was performed in a layer on a special curd-finishing table.Pressing took 3.5 h at a maximum pressing force of 3 kg per 1 kg of cheese.Samples were packaged in paper foil [16].The cheeses were stored under refrigerated conditions at 4 ± 0.3 • C and analyzed within the first 24 h after production.
foil [16].The cheeses were stored under refrigerated conditions at 4 ± 0.3 °C and analyzed within the first 24 h after production.
Figure 1.Samples of fresh white cheeses from buttermilk with polymerized whey protein.FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.

Composition and Cheese Yield
The moisture in the prepared fresh white cheese from buttermilk was determined by standard methods, AOAC 926.08 [29].Fat content was determined using standard methods, ISO 1735 [30].The content of total nitrogen (TN), casein nitrogen (CN), non-casein nitrogen (NCN), and non-protein nitrogen (NPN) were determined according to methods described by Svanborg et al. [31].The content of total protein (TP) and whey protein (WP) was calculated according to the following equations [32]: where 6.38 represents the factor indicated for proteins derived from milk.Titratable acidity was determined by standard methods, AOAC 920.124 [33].pH was measured using a CP-402 pH-meter (Elmetron, Zabrze, Poland) equipped with a IONODE IJ44A electrode (Ionode Pty. Ltd., Tennyson, Australia).The cheese yield (CY) was calculated according to Hanafy et al.'s [14] methods with modifications: Samples of fresh white cheeses from buttermilk with polymerized whey protein.FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.

Composition and Cheese Yield
The moisture in the prepared fresh white cheese from buttermilk was determined by standard methods, AOAC 926.08 [29].Fat content was determined using standard methods, ISO 1735 [30].The content of total nitrogen (TN), casein nitrogen (CN), non-casein nitrogen (NCN), and non-protein nitrogen (NPN) were determined according to methods described by Svanborg et al. [31].The content of total protein (TP) and whey protein (WP) was calculated according to the following equations [32]: where 6.38 represents the factor indicated for proteins derived from milk.Titratable acidity was determined by standard methods, AOAC 920.124 [33].pH was measured using a CP-402 pH-meter (Elmetron, Zabrze, Poland) equipped with a IONODE IJ44A electrode (Ionode Pty. Ltd., Tennyson, Australia).The cheese yield (CY) was calculated according to Hanafy et al.'s [14] methods with modifications: CY % = amount of cheese (kg)/amount of buttermilk (kg) • 100 (3)

Texture
Texture parameters were measured using a texturometer (Stable Micro Systems Ltd., Surrey, UK) equipped with an attachment: hardness and brittleness were measured using A/WEG attachment: pre-test speed 1.0 mm/s, test speed 2.0 mm/s, post-test speed 10.0 mm/s, and distance 10.0 mm; firmness and stickiness were measured using P/1S attachment: pre-test speed 1.5 mm/s, test speed 2.0 mm/s, post-test speed 10.0 mm/s, and distance 5 mm.Results were recorded using Texture Exponent E32 version 4.0.9.0 software (Godalming, Surrey, UK).

Peptonization
The cheese was fragmented to obtain a grain with a diameter of approximately 5 mm.Fragmented cheese in the form of a layer (h = 6 cm) was spread on perforated trays, which were transferred to the ripening room.The conditions during the process in the ripening room: time 3 days, temperature 25 ± 1 • C, and a relative humidity >75 RH.The cheese was turned over manually on the trays twice a day.

Statistical Evaluation
Verification of statistical hypotheses was achieved using a level of significance of α = 0.05 by a two-way analysis of variance followed by Tukey's HSD post hoc test for multiple comparisons.Data were analyzed using Statistica data analysis software, version 13 (TIBCO Software Inc., Palo Alto, CA, USA).

Composition and Cheese Yield
The obtained results showed no differences in moisture, fat content, titratable acidity, and pH among all the analyzed samples (Table 1; p > 0.05).The introduction of whey proteins to buttermilk in the production of the FWC increased the TN in the analyzed samples by 7.4% in the FWC/WPC and by 10.6% in the FWC/SPWP compared to the fresh white cheese with no additive (p < 0.05).However, no TN differences were found between the samples of FWC/SPWP and FWC/DPWP (p > 0.05).The TP in the control sample was 167.4 g/kg and approx.4% lower than in the other analyzed samples (p < 0.05).The TP content was the same among the samples with the addition of the whey protein concentrate and whey protein concentrate after the polymerization process (p > 0.05).No differences were observed between samples in terms of CN and NPN (p > 0.05), while the NCN concentration after the addition of whey proteins (regardless of the polymerization process) increased (p < 0.05).According to Masotti et al. [34], during cheese production, unused whey should be recycled; therefore, the introduction of whey proteins in cheese production is an innovative approach to responding to consumers' expectations of a product with a new texture and functionality.Mileriene et al. [35] reported that curd cheese supplemented with thermo-coagulated whey proteins is a response to the global interest in sustainable dairy foods.FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins; TN, total nitrogen; CN, casein nitrogen; NCN, non-casein nitrogen; NPN, non-protein nitrogen; TP, total protein; WP, whey protein.a-c different small letters in superscript in the rows indicate between parameters statistically significant differences (p = 0.05).
Studies have shown that the introduction of whey proteins in buttermilk cheese production increases CY over 2-fold (Table 1; p < 0.05).The CY can be increased by increasing the fat and protein content; stopping or re-adding whey proteins; and introducing other milk components (e.g., lactose; ash; moisture) [14].Elbarbary and Saad [36] described the quality of buffalo's milk soft cheese using the addition of camel's whey protein concentrate and showed that the higher the amount of added WPC, the higher CY.The authors suggested that the increase in CY may be related to the addition of WPC powder and/or denatured WPs, which resulted from heat treatment.This enhanced the integration of whey proteins into cheese or the higher retention of serum in the cheese matrix while increasing the CY.As shown by Stankey et al. [37], a denatured whey protein has a better ability to bind water, thus increasing the moisture content in cheese and the CY.The same observations are made by Perreault et al. [38], where a denatured whey protein concentrate significantly increased CY (from 12.5% to 15% compared to the control) as a result of the higher cheese moisture.Giroux et al. [39] evaluated the cheesemaking properties of milk, where the denaturation of whey proteins resulted in a higher CY.

Texture
A 3.7-fold reduction in the hardness of the FWC/WPC (Table 2; Figure 2) was observed compared to the FWC (p < 0.05).According to Hanafy et al. [14], the introduction of 2% to 4% of a WPC in cheese production increased the hardness, but the addition of 6% significantly reduced the hardness.The same authors suggested that the characteristics that determine cheese texture were moisture, fat, pH, and the structure of the protein matrix.Similar results were presented by Mohamed [40], where the impact of the addition of 1% to 3% WPC in the production of Kariesh cheese was analyzed.The results showed that the hardness, cohesiveness, springiness, gumminess, and chewiness values decreased after the addition of inulin or a WPC.The addition of single-heated polymerized whey proteins to buttermilk reduced the cheese hardness by 40% (FWC/SPWP; p < 0.05) compared to the control sample but promoted a 2-fold increase in hardness compared to the FWC/WPC (p < 0.05).Sołowiej et al. [41] showed that the addition of polymerized whey proteins thickened the cheese mass due to their ability to emulsify fat and increase water absorption.Casein could crosslink with whey proteins in cheesemaking.This leads to the cheese possessing a higher hardness [42].However, in our research, the further heating of the whey proteins and the addition of a double-heated polymerized whey protein significantly decreased the hardness.The addition of whey proteins (regardless of type) to buttermilk decreased firmness (compared to FWC; p < 0.05).Hence, in accordance with the results presented by Cais-Sokoli ńska et al. [16], the addition of whey protein concentrates in powder after the polymerization process to buttermilk in the production of buttermilk cheese caused a significant decrease in firmness (despite the use of other firmness measurement conditions).There were no differences observed in brittleness among all the cheese samples (p > 0.05), and the stickiness increased 3-fold only for the FWC/WPC compared to the control sample.The obtained results suggested that the texture of fresh white cheese from buttermilk could be modified via the modification of the composition of the main raw material with a simultaneous thermal modification of whey protein concentrates.This was previously confirmed by Domingos et al. [43], where the texture problem caused by fat reduction could be improved through the addition of a WPC.Tashakori et al. [44] found that the addition of 20% WPC improved the overall texture of spread cheese.However, Mohamed [40] reported that the ability of whey proteins to form gels that could hold water, lipids, and provide the appropriate texture was important for consumer acceptability.After 10 days of cold storage, significant changes were found in the hardness, firmness, and stickiness parameters, mainly for FWC/SPWP (Table 2; Figure 1).The hardness and firmness increased 2-fold, and stickiness showed a 2-fold decrease (FWC/SPWP; p < 0.05).Refrigerated storage had no effect on the brittleness of all the samples analyzed (p > 0.05).According to Gamlath et al. [17], denatured aggregates of whey proteins could avoid the impairment of rennet gelation caused by native whey proteins, and the combination of heat treatment with ultrasonication of whey proteins could potentially improve cheese texture.; FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.a-c, A-B different small letters in superscript in the rows and different capital letters in columns indicate statistically significant differences between parameters (p = 0.05).

Color
No differences in color were found between the samples of FWC/SPWP and FWC/DPWP (Table 3; p > 0.05).The least lightness was found in the cheese with a WPC, which was approx.6% lower compared to the control sample (FWC; p < 0.05) and 5% lower compared to samples with polymerized whey proteins (p < 0.05).The cheese sample with a WPC was also characterized by the smallest whiteness index.This was consistent with the results reported by Cais-Sokoli ńska et al. [16], in which the buttermilk cheese with added WPC powder was darker than the samples of cheese with added polymerized whey proteins, and the calculated value of the total color difference (∆E) was above 3.3.Such a result may negatively impact the consumer ratings of overall desirability.Brodziak et al. [45] also showed that the introduction of whey protein powder to yogurt caused the final product to be further from the ideal whiteness standard and thus less light.; FWC, fresh white cheese from buttermilk; FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.

Color
No differences in color were found between the samples of FWC/SPWP and FWC/DPWP (Table 3; p > 0.05).The least lightness was found in the cheese with a WPC, which was approx.6% lower compared to the control sample (FWC; p < 0.05) and 5% lower compared to samples with polymerized whey proteins (p < 0.05).The cheese sample with a WPC was also characterized by the smallest whiteness index.This was consistent with the results reported by Cais-Sokolińska et al. [16], in which the buttermilk cheese with added WPC powder was darker than the samples of cheese with added polymerized whey proteins, and the calculated value of the total color difference (ΔE) was above 3.3.Such a result may negatively impact the consumer ratings of overall desirability.Brodziak et al. [45] also showed that the introduction of whey protein powder to yogurt caused the final product to be further from the ideal whiteness standard and thus less light.; FWC, fresh white cheese from buttermilk; FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins; GU, gloss.a-c, A-B different small letters in superscript in the rows and different capital letters in columns indicate statistically significant differences between parameters (p = 0.05).
The addition of whey proteins after the polymerization process in the production of fresh white cheese from buttermilk resulted in an increased whiteness index and reduced yellowness index by 4.4% and 13.6%, respectively, compared to the FWC/WPC.The cheese with a WPC also had the highest browning index and chroma (Table 3; p < 0.05).The addition of whey proteins increased the gloss of the analyzed cheese samples compared to the control sample (p < 0.05).The gloss of the cheeses with a whey protein concentrate and polymerized whey proteins was the same (p > 0.05).According to Kampf and Nussinovitch [46] and Youssef et al. [47], gloss is an important parameter, assessed, e.g., in the selection of a cheese coating.After 10 days of cold storage, the lightness decreased in the FWC/WPC and increased in the FWC/SPWP, but the differences were less than 1% (p < 0.05).In the FWC/SPWP and FWC/DPWP cheeses, the whiteness index after 10 days of storage increased slightly above 1% (p < 0.05).In all the samples, after 10 days of refrigerated storage, the chroma parameter decreased (p < 0.05).Color is the first sense that registers with the consumer, who use it to accept or reject the product [48,49].Whey proteins may undergo slight color changes when heated [50].According to Ortega et al. [51], the color of whey proteins after heat treatment correlated with antioxidant activity due to the Maillard reaction.

Peptonization
Water loss from cheese during the cheese curing ranged from 4.7 (FWC) to 5.1% (FWC/DPWP).The cheese became glassy/transparent during melting.The content of uncrushed curd that remained white ranged from 27% in FWC/DPWP to 74% in FWC/SPWP (Figure 3).There were no differences in the range of the casein peptonization of curd between the FWC and FWC/DPWP.A relationship was demonstrated between the scope of the casein peptonization of curd, expressed in the amount of grain glassiness, and the degree of cheese fragmentation.The FWC/SPWP cheese, which had the most clamminess and therefore was the least fragmentated, was characterized by the least casein peptonization of curd.
According to El-Salam et al. [52], the ripening of cheese is a slow process due to its extended storage time.The occurring microbiological and biochemical changes lead to a change in taste and consistency.Ripening involves the natural decomposition of proteins (peptonization of casein) until the curd becomes glassy.The cheese then most often grows Galactomyces geotrichum, which is capable of biosynthesizing 2-phenylethanol and related rose-like aroma compounds from l-phenylalanine [53].Next, bacteria with proteolytic and lipolytic abilities are important.The secreted hydrolytic enzymes cause proteolysis of casein proteins, and the products of proteolysis, i.e., peptones, peptides, amino acids, and ammonia, give the cheese its characteristic taste and smell.During the casein peptonization of curd, its active acidity is significantly reduced from a pH of 4.4 to a pH above 5.0, among others, due to the decomposition of lactic acid into carbon dioxide and water.The changes that occur during the casein peptonization of curd have been thoroughly described in the literature.Soltani et al. [54] showed that the proteolysis of cheese can be influenced by the salt concentration in its production.
In this research, the casein peptonization of curd is a process used to increase its utility value during the production of cheese based on ripened cheese and its greater culinary use.The use of the casein peptonization of curd is important, for example, in the production of fried ripened curd cheese.Fresh cheese used for the production of fried ripened curd cheese is crushed and stored in a ripening room, where an extensive proteolysis of casein takes place at a temperature of 16-27 degrees for about 3 days [55].According to Rychlik et al. [56], fried ripened curd cheese is characterized by a specific aroma and taste that are closely related to the particular cheese manufacturing technology.This is important in the evaluation of cheeses used, for example, as fondue, for pizza, or in casseroles [57].This is a stage of production that definitely influences the specificity and uniqueness of future cheeses, such as Brennkäse, Kochkäse, Cancoillotte, Glundner Käse, and Wielkopolski fried cheese.
casein takes place at a temperature of 16-27 degrees for about 3 days [55].According to Rychlik et al. [56], fried ripened curd cheese is characterized by a specific aroma and taste that are closely related to the particular cheese manufacturing technology.This is important in the evaluation of cheeses used, for example, as fondue, for pizza, or in casseroles [57].This is a stage of production that definitely influences the specificity and uniqueness of future cheeses, such as Brennkäse, Kochkäse, Cancoillotte, Glundner Käse, and Wielkopolski fried cheese.

Conclusions
In traditional cheesemaking, whey proteins are lost in the whey.Therefore, it is considered reasonable to increase the technological quality of buttermilk cheese through the introduction of whey protein concentrates to buttermilk.The use of buttermilk after the production of butter and whey proteins forms cheese whey, which is part of the global trend of sustainable food production and closed-loop food production.The obtained results can significantly influence the development of dairy products and teach technologists in the dairy industry how to use whey protein aggregates to modify the texture and color and improve the yield of fresh white cheese.The addition of whey proteins after heat treatment in the production of fresh white cheese from buttermilk increases its cheese yield and significantly affects the texture and color of the cheese.The cheese with a whey protein concentrate was darker, so there is a concern that it might not be accepted by consumers.This research also showed a relationship between the degree of cheese grinding and its ability to facilitate the casein peptonization of curd.The casein peptonization of curd is important in the assessment of the cheeses used, e.g., as fondue, for pizza, and in casseroles.

Figure 1 .
Figure1.Samples of fresh white cheeses from buttermilk with polymerized whey protein.FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.

Figure 2 .
Figure 2. Texture of fresh white cheeses from buttermilk with polymerized whey protein.(a) Hardness and brittleness measured using attachment A/WEG; (b) firmness and stickiness measured using attachment p/1S; FWC, fresh white cheese from buttermilk; FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.

Figure 2 .
Figure 2. Texture of fresh white cheeses from buttermilk with polymerized whey protein.(a) Hardness and brittleness measured using attachment A/WEG; (b) firmness and stickiness measured using attachment p/1S; FWC, fresh white cheese from buttermilk; FWC, fresh white cheese from buttermilk; FWC/WPC, fresh white cheese from buttermilk with whey protein concentrate; FWC/SPWP, fresh white cheese from buttermilk with single-heated polymerized whey proteins; FWC/DPWP, fresh white cheese from buttermilk with double-heated polymerized whey proteins.

Figure 3 .
Figure 3.Samples of cheeses from buttermilk with polymerized whey proteins before and during the casein peptonization of curd.(a) FWC before the casein peptonization of curd; (b) FWC/WPC before the casein peptonization of curd; (c) FWC/SPWP before the casein peptonization of curd; (d) FWC/DPWP before the casein peptonization of curd; (e) FWC during the casein

Figure 3 .
Figure 3.Samples of cheeses from buttermilk with polymerized whey proteins before and during the casein peptonization of curd.(a) FWC before the casein peptonization of curd; (b) FWC/WPC before the casein peptonization of curd; (c) FWC/SPWP before the casein peptonization of curd; (d) FWC/DPWP before the casein peptonization of curd; (e) FWC during the casein peptonization of curd; (f) FWC/WPC during the casein peptonization of curd; (g) FWC/SPWP during the casein peptonization of curd; (h) FWC/DPWP during the casein peptonization of curd.

Table 1 .
Composition and cheese yield of fresh white cheeses from buttermilk with polymerized whey proteins.

Table 2 .
Texture of fresh white cheeses from buttermilk with polymerized whey protein.

Table 3 .
Color of fresh white cheeses from buttermilk with polymerized whey proteins.

Table 3 .
Color of fresh white cheeses from buttermilk with polymerized whey proteins.