Proteolysis In Cheese Research Articles

Effect of cheese coagulants on American-style natural cheese proteolysis and functional characteristics of process cheese made therefrom

Recombinant bovine chymosin (RBC) is an enzyme routinely used in cheese manufacture. Recombinant camel chymosin (RCC) is a milk coagulant with higher clotting activity and less proteolytic activity for natural cheese manufacture. This study aimed to determine the effect of RCC and RBC on the proteolysis of natural cheese and the functionality of processed cheese (PC). Six American-style natural cheeses were manufactured utilizing two different chymosin treatments and used to produce PC at 1 month of ripening. The natural cheese made using RCC had a significantly (P < 0.05) lower level of primary proteolysis and a lower degree of hydrolysis of αS1-CN and β-CN. The RCC treatment's hot viscosity, hardness, and loss tangent were significantly (P < 0.05) higher than the RBC in the PC. These results demonstrate that RCC results in a reduced level of primary proteolysis in a natural cheese, and when utilized in PC, it increases firmness and decreases meltability.

Protein fractionation by microfiltration of goat milk: Influence on proteolysis, metabolites and sensory characteristics of cheeses produced throughout lactation

This study addresses seasonal variations in goat milk by examining the effects of microfiltration (MF) and micro- and diafiltration (MDF) in standardising goat milk composition for cheese production. The research focuses on MF and MDF treatments at two lactation stages, analysing their impact on the quality of a hard goat milk cheese. Key parameters such as total solids, pH, organic acids, free amino acids, protein profiles, and sensory properties during cheese ripening were evaluated. Sensory attributes were assessed using Quantitative Descriptive Analysis (QDA), revealing different profiles between treatments. The MF cheeses showed a balanced profile, while MDF cheeses varied more in sourness, acidity, and texture, also influenced by lactation stage.

Impact of preacidification on the functionality and insoluble calcium levels of Low-Moisture Part-Skim Mozzarella made from high-casein milk

The use of low-concentration factor ultrafiltered (LCF-UF) milk for cheesemaking has become popular in recent years. Research on using LCF-UF milk to make low-moisture part-skim (LMPS) Mozzarella manufacture is limited due to concerns about the negative impact of the higher casein content on functional properties, such as melt and stretch. Pre-acidification (PA) (reflects acid added to milk before the addition of the starter culture) has been used in low-fat and nonfat Mozzarella cheeses to lower calcium levels and improve their texture and melting properties. We explored the use of PA to reduce the insoluble calcium content of cheese (calcium that is a crosslinking material for the casein proteins) and its impact on the functionality of LMPS Mozzarella made from high casein (4.2%) milk. Seven vats of LMPS Mozzarella, with a control (no PA), 2 pH values for PA (6.40 and 6.00) and 3 different acidification methods (use of acetic, citric, or carbonic acid from carbon dioxide) were evaluated for their impact on solubilization of colloidal calcium phosphate during LMPS manufacture. Composition, proteolysis, microstructural and functional changes in the LMPS cheeses were monitored during 90 d of refrigerated storage. All cheeses had similar composition except for the cheese made with milk PA with carbonic acid, which had a lower fat-in-dry matter probably due to foaming observed in this sample during the gas sparging. The cheese made with milk PA with citric acid to pH 6.00 had the lowest amount of total and insoluble calcium compared with other cheeses at all steps during cheese manufacture and storage, likely due to the calcium chelating ability of citric acid. The cheese that was made with milk PA with citric acid to pH 6.40 had a trend of slightly lower (not significant) total and insoluble calcium during cheese manufacture compared with other cheeses that were made with milk PA to pH 6.40. The pH value in all the cheeses remained similar throughout 90 d of storage, whereas the cheese that was made with milk PA with citric acid to pH 6.00 had the lowest pH values during storage. Treatment significantly (P < 0.05) impacted instrumental hardness, the maximum loss tangent during heating, the melting temperature and the storage modulus values measured at 70°C. Proteolysis was not impacted by treatment suggesting that typical aging should occur. Cheese that was PA with citric acid to pH 6.00 initially had lower maximum loss tangent values and higher hardness, possibly due to the lower pH value of this cheese. The performance of cheeses on pizza was assessed using Sensory Spectrum® method and quantitative descriptive analysis. The PA of cheese milk with citric acid helped to reduce the insoluble Ca level and at 30 and 90 d of storage, these cheeses had lower first chew hardness, lower chewiness, and lower strand thickness values compared with other cheeses. The use of PA could help improve the functionality of LMPS Mozzarella made from milk high in casein with citric acid being the most efficient in dissolving the insoluble calcium from casein.

The role of microbial coagulants on the physicochemical, proteolysis, microstructure and sensory properties of low-fat Edam cheese manufactured from ultrafiltered buffalo milk

This work investigates the influence of using microbial coagulants, including Rhizomucor miehei (MCR) protease and Cryphonectria parasitica (MCC) protease, on the quality characteristics of low-fat Edam cheese made from ultrafiltered buffalo milk (LFUE). Concurrently, a benchmark with calf rennet (CR) has been also performed. Throughout a 90-day ripening period, the cheeses were assessed for their physicochemical features, proteolysis, texture, free amino acid and free fatty acid content, microstructure, and sensory attributes. The study revealed that both microbial coagulants had no significant impact on the physicochemical composition and firmness of the cheeses while slightly affected the free fatty acids. Cheeses made with microbial coagulants displayed higher proteolysis, with MCR and MCC cheeses exhibiting greater levels of water-soluble nitrogen and 12% trichloroacetic acid-soluble nitrogen than CR cheese. MCR and MCC cheeses exhibited more extensive breakdown of αs- and β-caseins, as indicated by the SDS-PAGE electrophoretogram, compared to CR cheese during ripening. As for the proteolytic activity, the microbial coagulant contributed to shaping the free amino acid content, microstructure, and sensory qualities of the cheeses. Notably, MCC cheese outperformed MCR or CR cheeses in terms of free amino acid levels. MCR and MCC cheeses resulted in smooth microstructures with uniform protein networks as observed by microscopy, while CR cheese displayed rough, granular surfaces. With the highest scores for appearance, body, texture, and flavor, MCC cheese demonstrated superior sensory properties compared with MCR and CR cheeses.

Autochthonous cultures to improve the quality of PGI Castellano cheese: Impact on proteolysis, microstructure and texture during ripening

The aim of this research was to find out the effect of different combinations of starter and non-starter cultures on the proteolysis of Castellano cheese during ripening. Four cheese batches were prepared, each containing autochthonous lactobacilli and or Leuconostoc, and were compared with each other and with a control batch, that used only a commercial starter. To achieve this, nitrogen fractions (pH 4.4-soluble nitrogen and 12 % trichloroacetic acid soluble nitrogen, polypeptide nitrogen and casein nitrogen), levels of free amino acids and biogenic amines were assessed. Texture and microstructure of cheeses were also evaluated. Significant differences in nitrogen fractions were observed between batches at different stages of ripening. The free amino acid content increased throughout the cheese ripening process, with a more significant increase occurring after the first 30 days. Cheeses containing non-starter lactic acid bacteria exhibited the highest values at the end of the ripening period. Among the main amino acids, GABA was particularly abundant, especially in three of the cheese batches at the end of ripening. The autochthonous lactic acid bacteria were previously selected as non-producers of biogenic amines and this resulted in the absence of these compounds in the cheeses. Analysis of the microstructure of the cheese reflected the impact of proteolysis. Additionally, the texture profile analysis demonstrated that the cheese's hardness intensified as the ripening period progressed. The inclusion of autochthonous non-starter lactic acid bacteria in Castellano cheese production accelerated the proteolysis process, increasing significantly the free amino acids levels and improving the sensory quality of the cheeses.

The effect of seed germination and Bacillus spp. on the ripening of plant cheese analogs.

The development of novel plant-based fermented food products for which no traditional templates exist requires the development of starter cultures. Although the principles of microbial flavor formation in plant-based analogs partially overlap with dairy fermentations, the composition of the raw materials and thus likely the selective pressure on the activity of starter cultures differs. Experiments that are described in this study explored the use of seed germination, the use of lactic acid bacteria, and the use of bacilli to reduce hygienic risks, to acidify plant milk, and to generate taste-active compounds through proteolysis and fermentative conversion of carbohydrates. The characterization of fermentation microbiota by culture-dependent and culture-independent methods also confirmed that the starter cultures used were able to control microbial communities throughout 90 d of ripening. Taken together, the results provide novel tools for the development of plant-based analogs of fermented dairy products.

Machine learning for the prediction of proteolysis in Mozzarella and Cheddar cheese

Proteolysis is a complex biochemical event during cheese storage that affects both functionality and quality, yet there are few tools that can accurately predict proteolysis for Mozzarella and Cheddar cheese across a range of parameters and storage conditions. Machine learning models were developed with input features from the literature. A gradient boosting method outperformed random forest and support vector regression methods in predicting proteolysis for both Mozzarella (R2 = 92%) and Cheddar (R2 = 97%) cheese. Storage time was the most important input feature for both cheese types, followed by coagulating enzyme concentration and calcium content for Mozzarella cheese and fat or moisture content for Cheddar cheese. The ability to predict proteolysis could be useful for manufacturers, assisting in inventory management to ensure optimum Mozzarella functionality and Cheddar with a desired taste, flavor and texture; this approach may also be extended to other types of cheese.

Properties of low-fat Cheddar cheese prepared from bovine–camel milk blends: Chemical composition, microstructure, rheology, and volatile compounds

Making cheese from camel milk (CM) presents various challenges due to its different physicochemical properties compared with bovine milk (BM). In this study, we investigated the chemical composition, proteolysis, meltability, oiling off, texture profile, color, microstructure, and rheological properties of low-fat Cheddar cheese (LFCC) prepared from BM-CM blends. LFCC was produced from BM or BM supplemented with 15% CM (CM15) and 30% CM (CM30), and analyzed after 14, 60, 120, and 180 d of ripening at 8°C. Except for salt content, no significant differences were observed among LFCC from BM, CM15, and CM30. The addition of CM increased the meltability and oiling off in the resulting cheese throughout storage. With respect to color properties, after melting, LFCC CM30 showed lower L* values than LFCC made from BM and CM15, and a* and b* values were higher than those of BM and CM15 samples. LFCC from CM30 also exhibited lower hardness compared with the other cheeses. Moreover, LFCC made from BM showed a rough granular surface, but cheese samples made from BM-CM blends exhibited a smooth surface. The rheological parameters, including storage modulus, loss modulus, and loss tangent, varied among cheese treatments. The determined acetoin and short-chain volatile acids (C2-C6) in LFCC were affected by the use of CM, because CM15 showed significantly higher amounts than BM and CM30, respectively. The detailed interactions between BM and CM in the cheese matrix should be further investigated.

Determination of the effects of proteolysis-based changes by adjunct lactobacilli on the bioactivity (ACE-inhibitory and antioxidant activities) of cheese: a model cheese study.

Bioactive properties, proteolysis and microbiology of model cheeses with and without adjunct lactobacilli (Lactobacillus helveticus, Lactiplantibacillus plantarum, Lactobacillus bulgaricus and L. casei) were studied during 120 days of storage at 8 or 16°C. Bioactive properties were observed in peptide fractions (< 3kDa, 3-10kDa, < 10kDa) separated using ultrafiltration membranes. Antioxidant activity of these fractions was determined by radical scavenging assays as ABTS [2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)]. Angiotensin-converting enzyme-inhibitory (ACE-i) activity (% and IC50) and peptide profiles of 70% ethanol-soluble and -insoluble fractions were determined by RP-HPLC. Use of lactobacilli as an adjunct culture significantly changed the RP-HPLC peptide profiles of the cheeses; however, slight changes were observed in the patterns of urea-polyacrylamide gel electrophoresis. Fractions smaller than 3kDa had higher ACE-i and antioxidant activities for all cheese samples. In conclusion, this study indicates that the addition of lactobacilli as an adjunct culture contributed to the formation of bioactive compounds in the model cheeses and also changed the proteolysis levels.

Characterization of traditional Wagashi cheese and effect of the addition of probiotic Lacticaseibacillus or Enterococcus strains on the biophysical and biochemical features of probiotic-enriched Wagashi cheeses.

The present study aimed at characterizing traditional Wagashi cheese while defining as well the contribution of probiotic Lacticaseibacillus or Enterococcus strains to the biophysical and biochemical features of probiotic Wagashi cheeses vacuum packed and stored at 4 °C for 30 days. The strains were added to the cheese during production and their effect on proteolysis, lipolysis, color, and textural features during refrigerated storage was assessed throughout storage using standard methods. All the parameters were affected by storage and strains. Proteolysis of traditional Wagashi cheese ranged between 0.4 and 0.75 mg/mL serine while those with added probiotics were between 0.12 and 0.98 mg/mL serine. As for lipolysis, values were comprised between 4.77 and 8.03 and 3.01–10.34% oleic acid for traditional and probiotic Wagashi cheese respectively. L. rhamnosus and L. plantarum were found to have a higher peptidolysis and lipase activity respectively. However, their addition didn’t affect the cheeses’ whiteness. Color parameters were affected by hardness, chewiness, and the dyeing process. The cheeses’ textural features except for springiness were affected by storage time, strains, and proteolysis. The present work shows the relevance of improving the scientific knowledge of both traditional and probiotic Wagashi cheese.

Comparing Different Packaging Conditions on Quality Stability of High-Pressure Treated Serra da Estrela Cheeses during Cold Storage.

Serra da Estrela cheese with a Protected Designation of Origin (PDO) is a traditional cheese that is wrapped in paper without vacuum. High-pressure processing (HPP), which requires vacuum packaging of the cheese, has been used for its cold pasteurization to overcome safety issues. In this study, two packaging systems were studied: non-vacuum greaseproof paper wrapping package and vacuum packaging in plastic film. Lactococci, lactobacilli, enterococci, and total mesophiles reached ca. 8 log cfu g-1 and 4-6 log cfu g-1 in control (unpasteurized) and HPP-treated cheeses, respectively, with no significant differences between packaging systems. Spoilage microorganisms' viable cell numbers were reduced to <3 log cfu g-1 (quantification limit) in HPP-treated cheeses, independently of the packaging system. Yeasts and molds reached >5 log cfu g-1 in non-vacuum paper-wrapped cheeses. A vacuum-packaging system enabled better control of cheese proteolysis, which was revealed to be closer to that of the original control cheese values at the end of the 10-month storage period. In addition, cheese stored under vacuum film packaging became harder than non-vacuum paper-wrapped cheeses at each time point. Overall, conventional non-vacuum paper wrapping is adequate for short storage periods (<3 months), but for long periods vacuum packaging in plastic film is preferable.

Colloidal stability of Camembert and Cheddar cheese feeds in the absence of emulsifying salts

To eliminate emulsifying salts (ES) from cheese powder production, it is essential to understand destabilisation behaviour of cheese feeds without any additives. In this study, cheese feeds of two most used cheeses in cheese powder production were prepared in the absence of emulsifying salts. Colloidal stability of cheese feeds as well as the possible destabilisation causes linked to cheese properties were investigated. Both feeds showed a rapid destabilisation with different separation behaviour. Camembert feed showed better colloidal stability, which was associated with higher component recovery (e.g., fat, protein) and higher viscosity. The presence of colloidal calcium was associated with the poor stability of Cheddar feed, while extensive proteolysis in Camembert cheese affecting protein functionality is suggested to be an important destabilisation factor for Camembert feed.

Study of the possibility of producing semi-hard cheeses from frozen goat’s milk

The article presents the results of a study of the quality indicators of semi-hard cheeses produced from defrosted goat’s milk. Natural and defrosted goat’s milk, semi-hard cheeses with a low temperature of the second heating were used as objects of research. Studies of defrosted goat’s milk were carried out after 6±1 days of its storage at a temperature of minus 18°C and subsequent defrosting at a temperature of 37±2°C for 60 minutes; natural goat’s milk — after storage for 24±12 hours at a temperature of 4±2°C. It was found that milk freezing and its subsequent defrosting did not affect the chemical composition of milk and the total content of microorganisms, but the number of somatic cells decreased. Cheeses were produced according to the traditional technological scheme of semi-hard cheese using a bulk mesophilic-thermophilic bacterial starter culture. There was no significant effect of the freezing process of goat’s milk on its technological properties: the duration of curd formation in both variants was (30±1) min, the duration of processing of cheese grain was (90±2) min. The level of syneresis was (55±2)% in the control, (55±6)% — in the test versions and was in the range of error of the method. The degree of transition of dry matter to whey was: in the control — (7.26±0.21)%, in the test — (7.21±0.32)%. It was found that there were no differences in the degree of proteolysis in cheeses during ripening. The values of the acidity the content of available fat in the cheeses of both variants was comparable. The organoleptic characteristics of cheeses at the standard age of 60 days had similar characteristics, both in terms of the degree of intensity of the cheese taste, and in the taste notes of “zest” and “spice”, typical of goat’s milk cheeses. The cheese texture of both variants was characterized as “homogeneous, moderately dense”. It has been established that the process of freezing goat’s milk does not reduce its cheese properties and the qualitative characteristics of the semi-hard cheese produced from it.

Enzymatic proteolysis during the conversion of milk into cheese

The transformation of milk into cheese occurs under the influence of many physicochemical, biochemical and microbiological processes, among which proteolysis plays a very important role. Proteolysis belongs to the most complex type of irreversible post-translational modification of proteins. Enzymatic proteolysis catalysts at different stages of cheese production are native milk enzymes, exo- and endopeptidases of starter and non-starter microorganisms, and milk-clotting enzymes. The article presents a brief overview of modern ideas about the properties, mechanism of action and specificity of the main representatives of enzymes that hydrolyze milk proteins at the stages of preparing milk for coagulation, during rennet coagulation and subsequent maturation of cheeses. These include the plasmin system of milk, enzymes of psychrotrophic bacteria and lactic acid microorganisms that enter milk both accidentally (non-starter microflora) and planned in the form of starter cultures from specially selected strains. Milk-clotting enzymes, having fulfilled their main function — milk coagulation — partially pass into cheese and, along with enzymes of starter microorganisms and plasmin, participate in proteolytic processes during cheese ripening. It is generally accepted that proteolysis in ripening cheeses is the most significant biochemical process that affects the formation of taste, aroma and texture along with lipolysis and glycolysis. The combination of proteolysis products (peptides, amino acids, amines, etc.) is individual for different types of cheese and varies depending on the technological parameters of production, including the duration of maturation. Proteolysis in cheeses has been studied by many scientists in various aspects. This review supplements the known information with new information, without claiming to be comprehensive.

Prevention of Fungal Contamination in Semi-Hard Cheeses by Whey-Gelatin Film Incorporated with Levilactobacillus brevis SJC120.

Cheese whey fermented by lactic acid bacteria (LAB) was used to develop an edible film with antifungal properties. Five LAB strains isolated from artisanal cheeses were screened for antifungal activity and incorporated into a whey-gelatin film. Of the strains tested, Levilactobacillus brevis SJC120 showed the strongest activity against five filamentous fungi isolated from cheese and cheese-making environment, at both 10 °C and 20 °C. The cell-free supernatant from L. brevis inhibited fungal growth by more than 80%. Incorporation of bacterial cells into the film did not alter the moisture content, water vapor permeability, or mechanical and optical properties. The whey-gelatin film was also able to maintain the viability of L. brevis cells at 107 log CFU/g after 30 days at 10 °C. In cheeses wrapped with L. brevis film, the size of fungal colonies decreased by 55% to 76%. Furthermore, no significant differences (p > 0.05) were observed in cheese proteolysis or in the moisture, fat, and protein content of the cheese wrapped with films. The results showed that whey-gelatin film with L. brevis SJC120 can reduce the contamination of cheese with filamentous fungi and could be used as an alternative to conventional cheese preservation and packaging.

Chemical characteristics, oxidation and proteolysis in cheese produced from fresh or stored milk subjected to heat treatments

Cheese produced from fresh, stored or heat pretreated (65°C for 15 s) milk subjected to pasteurisation (72°C or 77°C for 15 s) was studied for chemical characteristics and proteolysis after 4 and 21 days of storage. Antioxidant activity was higher in cheese from fresh milk than in cheese from stored and heat pretreated milk. Malondialdehyde content as an index of lipid oxidation increased in cheese made with pretreated and preserved milk than in cheese made with fresh milk. Antioxidant activity and lipid oxidation were not significantly affected by pasteurisation temperature. Proteolysis increased during cheese maturation regardless of milk heat treatments.

Impact of the use of skim milk powder and adjunct cultures on the composition, yield, proteolysis, texture and melting properties of Cremoso cheese

The influence of the use of milk enriched with skim milk powder (SMP) and the incorporation of two adjunct cultures, Lacticaseibacillus paracasei 90 and Lactobacillus rhamnosus 73, on cheese yield, composition, microbial counts, proteolysis, texture and melting properties were assessed in Cremoso cheese. Cheeses with and without SMP, and with and without adjunct cultures were made. The incorporation of SMP increased the cheese yield, produced a slight increase in the cheese chewiness and hardness, increased the levels of whey proteins retained in the cheese and produced some changes in the peptide profiles. Regarding adjunct cultures, both strains maintained high levels in cheeses, increased the soluble nitrogen and decreased the hardness and chewiness. In conclusion, the addition of SMP to cheese milk could increase the operating capacity of the plant, maintaining the cheese quality, while the adjunct cultures showed a good performance in cheeses made with both control and enriched milk.

Effect of Bear Garlic Addition on the Chemical Composition, Microbiological Quality, Antioxidant Capacity, and Degree of Proteolysis in Soft Rennet Cheeses Produced from Milk of Polish Red and Polish Holstein-Friesian Cows.

This study aimed to assess the effect of milk source and bear garlic addition on the selected properties of soft rennet cheese. Cheeses were produced from cow milk derived from two sources: Polish Red cows (PR) and Polish Holstein-Friesian cows (PHF) with a 0.5% (w/w) addition of bear garlic (Allium ursinum L.) dried leaves. Chemical composition and fatty acid profiles (GC) were determined in fresh cheeses. Fresh and stored for two weeks cheeses were subjected to microbiological studies, i.e., total aerobic bacteria count (TABC); count of Lactococcus sp., yeast and molds; coliforms; analysis of the proteolysis extension by means of o-phthaldialdehyde (OPA) assay and free amino acids content (HPLC); antioxidant capacity as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP); as well as pH and water activity. Cheeses with bear garlic herbs were more prone to proteolysis but this was not accompanied by any effect on the microbial counts, water activity or pH. Cheeses produced from PR milk contained less monounsaturated fatty acids (MUFA) but were richer in n-3 PUFA and had a lower n-6/n-3 FA ratio than cheeses from PHF milk. Bear garlic addition increased DPPH anti-radical power but had less of an effect on the FRAP values.

Slower proteolysis in Cheddar cheese made from high-protein cheese milk is due to an elevated whey protein content.

A growing number of companies within the cheese-making industry are now using high-protein (e.g., 4-5%) milks to increase cheese yield. Previous studies have suggested that cheeses made from high-protein (both casein and whey protein; WP) milks may ripen more slowly; one suggested explanation is inhibition of residual rennet activity due to elevated WP levels. We explored the use of microfiltration (MF) to concentrate milk for cheese-making, as that would allow us to concentrate the casein while varying the WP content. Our objective was to determine if reducing the level of WP in concentrated cheese milk had any impact on cheese characteristics, including ripening, texture, and nutritional profile. Three types of 5% casein standardized and pasteurized cheese milks were prepared that had various casein:true protein (CN:TP) ratios: (a) control with CN:TP 83:100, (b) 35% WP reduced, 89:100 CN:TP, and (c) 70% WP reduced, 95:100 CN:TP. Standardized milks were preacidified to pH 6.2 with dilute lactic acid during cheese-making. Composition, proteolysis, textural, rheological, and sensory properties of cheeses were monitored over a 9-mo ripening period. The lactose, total solids, total protein, and WP contents in the 5% casein concentrated milks were reduced with increasing levels of WP removal. All milks had similar casein and total calcium levels. Cheeses had similar compositions, but, as expected, lower WP levels were observed in the cheeses where WP depletion by MF was performed on the cheese milks. Cheese yield and nitrogen recoveries were highest in cheese made with the 95:100 CN:TP milk. These enhanced recoveries were due to the higher fraction of nitrogen being casein-based solids. Microfiltration depletion of WP did not affect pH, sensory attributes, or insoluble calcium content of cheese. Proteolysis (the amount of pH 4.6 soluble nitrogen) was lower in control cheeses compared with WP-reduced cheeses. During ripening, the hardness values and the temperature of the crossover point, an indicator of the melting point of the cheese, were higher in the control cheese. It was thus likely that the higher residual WP content in the control cheese inhibited proteolysis during ripening, and the lower breakdown rate resulted in its higher hardness and melting point. There were no major differences in the concentrations of key nutrients with this WP depletion method. Cheese milk concentration by MF provides the benefit of more typical ripening rates.

The effects of the use of whey protein as a fat replacer on the composition, proteolysis, textural, meltability, microstructural, and sensory properties of reduced-fat Boru-type Künefe cheese during storage

Boru-type Künefe cheeses were produced from standardised cow milk (fat ratios: 2, 1.5, 1, 0.5%) using whey protein concentrates (whey protein ratios: 0, 0.5, 1, 1.5%, respectively) and stored at 4 °C for 90 days. The composition, proteolysis, texture, meltability, microstructure, and sensory properties of cheeses were examined during storage. The effects of using different fat and whey protein ratios were determined to be significant (p <0.05) on the composition (except pH), texture (except springiness and cohesiveness), meltability and sensory properties of cheeses. Storage period affected significant (p <0.05) pH, titration acidity, fat content, meltability values, odour score, hardness, texture (except springiness) and proteolysis properties. It was determined that there were differences in the microstructure of the cheeses. Overall, the cheeses produced with 0.5% whey protein and 1.5% fat milk were similar to the control cheese and determined the most suitable cheese in terms of some properties.