A Survey on Selected Chemical,Biochemical and Sensory Properties of Kes Cheese,A Traditional Turkish Cheese

Kes, a traditional Turkish dairy product, is commonly produced in the northern Anatolian region of Turkey. Kes samples were obtained from local markets in Ordu vicinity and were investigated for some chemical, biochemical, and sensorial analyses. The mean values of dry matter (DM), fat, fat in DM, salt, salt in DM, ash, and pH were found to be 56.17 ± 6.07, 8.79 ± 2.84, 15.78 ± 5.39, 3.22 ± 1.35, 5.68 ± 2.19, 4.31 ± 1.29 g/100 g cheese, and 4.75 ± 0.59, respectively. The WSN/TN, TCA-SN/TN and PTA-SN/TN values were between 1.79–28.53, 1.67–23.24, and 0.44–17.56%, respectively. SDS-PAGE showed that both α_s–CN and β–CN fractions were not completely hydrolyzed in all Kes cheese samples. α_s–CN, β–CN, and γ-casein and other peptides fractions determined as 34.57 ± 5.21, 33.74 ± 4.21, and 31.37 ± 6.82%, respectively. Panelists gave high scores (above 7 out of 10) to all samples for all the attributes considered.     

Effect of some technological parameters on microbiological, chemical and sensory qualities of Civil cheese during ripening

The objective of this research was to determine the effects of different ripening methods [brine salting, dry salting, incorporating with Lor cheese (LR) and vacuum packaging] of Civil cheeses on its microbiological, chemical and sensory properties. Civil cheeses were analysed on the 2nd, 30th, 60th and 90th day of ripening. Chemical compositions of the cheeses were significantly different. While the highest dry matter and titratable acidity values were determined on dry salted cheeses, the highest fat and fat in dry matter contents were found in Civil cheese ripened together with LR. The water-soluble nitrogen and ripening index values were lower in cheese ripened incorporating with LR. Excessive proteolysis was not seen in any of cheese samples. The ripening in different methods affected microbiological and sensory properties of Civil cheese. Panellists preferred vacuum packaging and dry-salting cheeses compared to the other samples on the 90th day of ripening.     

Effects of Packaging Materials and Filling Methods on Selected Characteristics of Otlu (Herby) Cheese

In this research, two kinds of filling methods (block and pieced) in two container types (pot and plastic) were used for the preparation of Otlu cheeses. The uses of different containers influenced (P < 0.01) acidity, pH, dry matter, fat contents and water soluble nitrogen. Degradation of α?s₁- and β-casein were higher in pieced cheeses in pot (P1F2). Also, breakdown products of casein were higher in P1F2 cheeses compared to others. The amounts of α?s₁- and β-caseins of all treatments decreased during ripening, while the amounts of α?s₁-I casein and breakdown products increased. The acceptability of cheeses in block form was higher.     

Primary and Secondary Proteolysis in Eleven Turkish Cheese Varieties

Levels of proteolysis of 75 samples belonging to 11 Turkish cheese varieties, including Civil, Canak, Dil, Divle Tulum, Ezine, Hellim, Malatya, Mihalic, Orgu, Urfa, and Van Otlu, were comparatively studied. The cheeses were mainly produced using traditional methods; however, some varieties were industrially produced. Chemical composition and the levels of soluble nitrogen fractions of the cheeses varied depending on the cheese variety. Gel electrophoresis of the cheeses showed that the samples presented different gel patterns with α_s1-casein being extensively degraded in many cheeses; whereas the hydrolysis of α_s1-casein in Malatya and Hellim was observed to be limited. Peptide profiles by RP-HPLC of the water-soluble fractions were largely different for many of the samples, but some similarities were visualized. Multivariate analysis of the RP-HPLC data grouped the cheeses according to their peptide profiles. The results suggested that each variety of cheese had different levels of proteolysis. The manufacturing technique and ripening conditions employed have played a determinative role on the proteolytic patterns of the cheeses analyzed.     

Relationships between proteolytic and lipolytic activity and sensory properties (taste–odour) of traditional Turkish white cheese

Protein and lipid changes and their effects on the sensory properties (taste–odour) of Turkish white cheese were studied. Mean values for the chemical properties of white cheese were: total solids (TS) 44.39 g/100 g; titratable acidity 2.15% (as lactic acid); pH value 4.50; fat-in-dry matter 47.80 g/100 g; salt-in-dry matter 8.65 g/100 g; total nitrogen (TN) 2.50 g/100 g; water-soluble nitrogen (WSN) 0.48 g/100 g; ripening index (RI) 18.98%; tyrosine 65.00 mg/100 g; acid degree value (ADV) 385.96 mg KOH/100 g fat; volatile fatty acids (VFA) 15.54 mL 0.1 N NaOH/100 g and total free fatty acids (TFFA) 1325.96 mg/100 g cheese. Sensory scores for taste and odour were 23.67 (out of 35) and 8.28 (out of 10), respectively. The chemical qualities of the cheeses, including acidity, dry matter, fat-in-dry matter and VFA had an effect on flavour ( P  < 0.05).     

Occurrence,origin and fate of pyroglutamyl-γ3-casein in cheese

During plasmin-catalysed proteolysis of β-casein (β-CN) in cheese, pyroglutamyl-γ₃-casein (pγ₃-CN), originates from the cyclisation of the N-terminal Glu of γ₃-CN (β-CN f108–209). This peptide progressively increased in content during ripening of Grana Padano and Parmigiano-Reggiano Protected Designation of Origin cheeses. A preliminary survey revealed pγ₃-CN in both hard and extra-hard cheese varieties; in semi-hard cheeses it was present only in mature samples. To understand the mechanisms of pγ₃-CN formation/degradation, in vitro trials (real cheese, model cheeses and buffered γ₃-CN solutions) were performed. Both the effect of cheese pH and the capacity of certain microorganisms to cyclise the N-terminal Glu residue of γ₃-CN were studied. The results suggested that pγ₃-CN formed spontaneously during cheese ripening, mainly at the acid pH characteristic of hard and extra-hard cheeses; the role of cyclase enzymes was negligible. Differences in pγ₃-CN degradation were observed due to the proteolytic activity of bacteria involved in the cheese ripening.     

A survey of the chemical,biochemical, microbiological and sensorial quality of Aho cheese,a traditional cheese from Eastern Black Sea Region,Turkey

Aho cheese, a traditional Turkish dairy product, is commonly produced in the eastern Black Sea region of Anatolia. In this study, 60 samples were collected and some biochemical, microbiological and sensory qualities were investigated. The mean values for dry matter, fat, protein, salt, ash and pH were 45.04, 8.10, 26.50, 9.58, 10.64 g/100 g and 5.07, respectively. Water‐soluble nitrogen (WSN), ripening index (WSN, % of TN) and acidity index were 0.59 g/100 g, 14.50% and 4.82 mg KOH/g fat, respectively. The mean values for saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids and polyunsaturated fatty acid/saturated fatty acid values were found to be 73.57, 23.08, 3.38 and 0.046 g/100 g fatty acids, respectively. Total aerobic mesophilic bacteria, yeast, mould and coliform counts were between 6.20–7.44, 4.84–6.96 and 0.00–2.45 log cfu/g, respectively.     

Microbiological and Chemical Properties of Cheese Helva Produced in Turkey

In this study, the microbiological and chemical properties of Cheese helva, one of the traditional cheeses varieties produced in Turkey, was studied. This cheese is called Cheese helva since it is produced from wheat flour and milk cream. Samples were randomly collected from different villages in the Erzurum province of Turkey. The average of total aerobic mesophilic bacteria (TAMB), yeast and mould, yeast, lactic acid bacteria (LAB), proteolytic bacteria, and lipolytic bacteria were determined 4.9 × 10⁷, 6.4 × 10⁴, 3.5 × 10³, 7.6 × 10⁶, 4.6 × 10³, and 8.6 × 10³ cfu/g, respectively. 44.44% of the Cheese helva samples had no coliform; the samples that were positive for coliform showed an average of 5.1 × 10³ cfu/g. Staphylococcus aureus was found < 10 cfu/g in analyzed samples. The Cheese helva was characterized by dry matter as 84.32 kg/100 kg cheese, fat as 37.44 kg/100 kg cheese, protein as 13.75 kg/100 kg cheese, NaCI as 0.58 kg/100 kg cheese, titratable acidity as 0.210%, pH as 5.30, ash as 1.49 kg/100 kg cheese, and carbohydrate as 38.56 kg/100 kg cheese. Cheese helva was found to have a high variation based on chemical composition. The microbiological tests revealed that there were high amounts of total bacteria, yeast and molds, molds, lactic acid bacteria, lipolytic bacteria, proteolytic bacteria, and coliforms.     

Lipolysis and proteolysis profiles of fresh artisanal goat cheese made with raw milk with 3 different fat contents

The objective of this study was to describe the proteolysis and lipolysis profiles in goat cheese made in the Canary Islands (Spain) using raw milk with 3 different fat contents (0.5, 1.5, and 5%) and ripened for 1, 7, 14, and 28 d. β-Casein was the most abundant protein in all cheeses and at all ripening times. Quantitative analysis showed a general decrease in caseins as ripening progressed, and degradation rates were higher for α_S1-casein than for β-casein and α_S2-casein. Furthermore, the degradation rate during the experimental time decreased with lower fat contents. The α_S2-casein and α_S1-casein levels that remained in full-fat and reduced-fat cheeses were less than those in low-fat cheese. In contrast, β-casein also showed degradation along with ripening, but differences in degradation among the 3 cheese types were not significant at 28 d. The degradation products increased with the ripening time in all cheeses, but they were higher in full-fat cheese than in reduced-fat and low-fat cheeses. The free fatty acid concentration per 100 g of cheese was higher in full-fat cheese than in reduced- and low-fat cheese; however, when the results were expressed as milligrams of free fatty acids per gram of fat in cheese, then lipolysis occurred more rapidly in low-fat cheese than in reduced- and full-fat cheeses. These results may explain the atypical texture and off-flavors found in low-fat goat cheeses, likely the main causes of non-acceptance.     

Characterization of Siahmazgi cheese,an Iranian ewe's milk variety: Assessment of physico-chemical,textural and rheological specifications during ripening

Siahmazgi cheese is an Iranian locally-made cheese produced from ewe's milk or a mixture of ewe and goat's milks in the suburbs of Rasht in the north of Iran. This kind of cheese is kept in sheepskin for six months under special condition which cause distinct physicochemical and textural characteristics. Therefore, in the present study the effect of ripening time (6 months) on the chemical, physicochemical, rheological and textural characteristics of Siahmazgi cheese (18 samples) was investigated. The rheological and textural properties were determined using rheometer (frequency sweep) and texture analyzer (uniaxial compression). Based on our findings, the measured values including pH, titratable acidity (TA), dry matter, fat, protein, ash, salt content, water soluble nitrogen in total nitrogen, and non-protein-nitrogen in total nitrogen significantly increased during ripening (P < 0.05). Furthermore, the results showed that the six-month ripened Siahmazgi cheese contained high values of dry matter (59.95 ± 0.08 g/100 g), salt (5.65 ± 0.05 g/100 g), and ash (7.24 ± 0.02 g/100 g). Regarding rheological and textural properties, storage modulus (G′), loss modulus (G″), fracture stress (σ_f) and firmness increased while loss tangent and fracture strain decreased.     

Genotypic identification of some lactic acid bacteria by amplified fragment length polymorphism analysis and investigation of their potential usage as starter culture combinations in Beyaz cheese manufacture

In this study, 2 different starter culture combinations were prepared for cheesemaking. Starter culture combinations were formed from 8 strains of lactic acid bacteria. They were identified as Lactococcus lactis ssp. lactis (2 strains), Lactobacillus plantarum (5 strains), and Lactobacillus paraplantarum (1 strain) by amplified fragment length polymorphism analysis. The effects of these combinations on the physicochemical and microbiological properties of Beyaz cheeses were investigated. These cheeses were compared with Beyaz cheeses that were produced with a commercial starter culture containing Lc. lactis ssp. lactis and Lc. lactis ssp. cremoris as control. All cheeses were ripened in brine at 4°C for 90 d. Dry matter, fat in dry matter, titratable acidity, pH, salt in dry matter, total N, water-soluble N, and ripening index were determined. Sodium dodecyl sulfate-PAGE patterns of cheeses showed that α_S-casein and β-casein degraded slightly during the ripening period. Lactic acid bacteria, total mesophilic aerobic bacteria, yeast, molds, and coliforms were also counted. All analyses were repeated twice during d 7, 30, 60, and 90. The starter culture combinations were found to be significantly different from the control group in pH, salt content, and lactobacilli, lactococci, and total mesophilic aerobic bacteria counts, whereas the cheeses were similar in fat, dry matter content, and coliform, yeast, and mold counts. The sensory analysis of cheeses indicated that textural properties of control cheeses presented somewhat lower scores than those of the test groups. The panelists preferred the tastes of treatment cheeses, whereas cheeses with starter culture combinations and control cheeses had similar scores for appearance and flavor. These results indicated that both starter culture combinations are suitable for Beyaz cheese production.     

The effect of lowering salt on the physicochemical,microbiological and sensory properties of São João cheese of Pico Island

São João cheeses with varying curd dry salting treatments were made with decreasing levels of salt (sodium chloride): 4 (control), 3, 2 and 1% (w/w), along with the salt‐free version. The cheeses were ripened at 11 °C over a 40‐day period, and the effect of lowering salt on the physicochemical, microbiological and sensory properties of the cheese was studied. Reduced salt resulted in a concomitant moisture decrease with protein increase, ash and sodium reduction among experimental cheeses at the same ripening day, but there were no significant differences in pH, acidity and fat, or in the microbiological quality. Triangle tests indicated perceptible differences between test and control cheeses at the level of 2% NaCl (w/w) or less, but not with the cheese salted with 3 g NaCl/100 g. Considering the sensory, the physicochemical and the microbiological results, the cheese formulated at 3% NaCl (w/w) (presenting a reduction of 25% in salt) is feasible on an industrial scale, being indistinguishable by the regular consumer.     

Study of the biochemical changes during ripening of Ahumado de Áliva cheese: a Spanish traditional variety

The changes in chemical composition, main physico-chemical parameters, classical nitrogen fractions, caseins and their degradation products, and some fat characteristics were studied during the ripening of ten batches of Ahumado de Áliva cheese, a traditional variety made in the north of Spain. The values of the different compositional and physico-chemical parameters at the end of the ripening did not differ significantly from those found in other cows' milk cheeses elaborated by similar technology. The low pH values are outstanding. The presence of residual lactose at the end of ripening is also relevant. Total soluble nitrogen and non-protein nitrogen increased very little during ripening. The evolution of the values of the different nitrogen fractions show that this cheese undergoes very little proteolysis and that the rennet is the main proteolytic agent. Using PAGE, it was possible to show that, throughout ripening, only 22% of α_s-casein and 9% of β-casein were degraded. The TBA value indicated that the fat of Ahumado de Áliva cheese does not undergo noticeable autooxidation during ripening. The acidity index of the fat also indicated that this cheese underwent little lipolysis during ripening.     

Characterization of the chemistry, biochemistry and volatile profile of Kuflu cheese, a mould-ripened variety

The chemistry, biochemistry and volatile compounds of Kuflu cheese, a Turkish mould-ripened variety were studied. A total of 29 samples were analysed and the titratable acidity, moisture, salt-in-moisture, fat-in-dry matter and total protein contents (as mean values) were 0.96%, 49.97%, 7.49%, 12.18% and 37.84%, respectively, and the pH of the cheeses was 6.29. Indices of proteolysis (i.e., the levels of pH 4.6- and trichloroacetic acid-soluble nitrogen) were high; however, these values were lower than those of other Blue cheeses probably due to proportionally higher levels of total nitrogen and salt-in-moisture in Kuflu cheese samples. Urea-polyacrylamide gel electrophoresis of the pH 4.6-insoluble fractions of the cheeses showed that both α_s1- and β-caseins were extensively degraded, but β-casein was less degraded than α_s1-casein. RP-HPLC peptide profiles of the pH 4.6-soluble fractions from Kuflu cheeses showed that some minor quantitative differences were found between the samples, while peptide profiles of the samples were qualitatively similar. One hundred and thirty-eight compounds were identified in the volatile fractions of Kuflu cheese by gas chromatography-mass spectrometry (GC-MS) using a solid-phase microextraction technique. Ketones and alcohols were the principal class of volatile components in Kuflu cheeses, and terpenes and sulphur compounds were found at substantial levels in the majority of the samples, but aldehydes and lactones were present at low levels. The RP-HPLC and GC-MS data were analysed by principal component analysis based on their peptide and volatile profiles, respectively. Kuflu cheeses obtained from different markets had some differences in terms of chemical composition, proteolysis and patterns of aroma compounds.     

The effect of mendi (Chaerophyllum sp.) on ripening of vacuum-packed herby cheese

The composition, biochemical and sensory parameters of control cheese (without herbs) and four herby cheeses at 0.5, 1, 2 and 3% herb levels (mendi, Chaerophyllum sp.) ripened at 4 ± 1°C for 90 days were compared. As herb levels increased from 0.5 to 3%, dry matter and pH value decreased significantly. However, dry matter of all cheeses showed similar changes during ripening. The salt content of samples changed from 3.44 to 5.47% during ripening. There was a tendency toward slightly higher titratable acidity in cheeses with more added herbs. Ripening index, trichloroacetic acid-soluble nitrogen/total nitrogen, phosphotungstic acid-soluble nitrogen/total nitrogen, and lipolysis values of the cheese samples were affected by adding herbs and by ripening time. The most acceptable sensory score was obtained with 1% added herbs.     

Residual clotting activity and ripening properties of vegetable rennet from Cynara cardunculus in La Serena cheese

Vegetable rennet extracted from Cynara cardunculus flowers is traditionally used in the manufacture of La Serena cheese. High levels of proteolytic enzymes of the flowers are responsible for its clotting activity and strong proteolytic action. The presence of residual coagulant in cheese and whey was measured by adding known amounts of vegetable rennet as internal standard. We found no differences between the residual coagulant activity of La Serena cheese compared with other types of cheese. The coagulant content detected at the end of four cheesemakings (vat of 830 l) in cheese and whey represented 27 and 78%, respectively, of the total amount added to milk. When measurements were carried out in 16 different cheeses, vegetable rennet appeared to be highly stable during cheese ripening. Cheese composition (moisture, pH, NaCl, fat and protein) was kept relatively constant during ripening, which seems to contribute to stability of residual activity. Electrophoretic analyses of water insoluble fractions from cheeses manufactured with vegetable rennet showed that α_s-casein was less susceptible to proteolysis than β-casein. The water soluble nitrogen/total nitrogen (WSN/TN) exhibited higher levels only during the first 30 days of ripening although non-protein nitrogen/total nitrogen (NPN/TN) ratio and amino acid nitrogen (NH₂-N) increased with ripening time.     

The effects of some starter cultures on the properties of Turkish White cheese

White cheese samples were manufactured from bovine milk using three different commercial direct vat starter cultures (DVS-1, -2 and -3) and a lyophilized culture, and ripened at 4 ± 1°C for 90 days. The composition, titratable acidity and ripening indices of the cheese samples were determined on the 2nd, 30th, 60th and 90th days of ripening. The ratios of total solids, protein and fat were higher for cheeses manufactured using DVS-2 and lyophilized cultures but the titratable acidity in cheese produced using DVS-3 and lyophilized cultures was higher (P < 0.01). The mean value of the ripening indices of the cheese produced using the lyophilized culture was lower than the cheeses produced with added DVS cultures (P < 0.05). The total solids, ash, salt ratios, titratable acidity and ripening indices values increased for all types of white cheeses during ripening (P < 0.05).     

Chemical and microbiological status and volatile profiles of mouldy Civil cheese,a Turkish mould‐ripened variety

The objective of this study is to characterise the gross chemical and microbiological status and identify the volatile compounds of mouldy Civil cheeses. A total of forty‐one samples were surveyed, and gross compositional status of the cheeses was (as mean values): 6.5 for pH, 6.2% for fat‐in‐dry matter, 51.8% for moisture and 15.3% for water‐soluble nitrogen (as% of total nitrogen). Chemical composition of the cheese samples varied widely. Mouldy Civil cheese has similar pH values and moisture contents when compared with blue‐type cheeses, but it has distinct feature for fat contents. The microbiological counts of the samples were found to be high and some samples contained coliform bacteria. A total of 95 volatiles, including esters (28), acids (6), ketones (12), aldehydes (3), alcohols (15), terpenes (10), sulphur compounds (3) and miscellaneous (18), were identified in the volatile fractions of the cheeses, and principal volatile groups were esters, alcohols and ketones.     

EFFECT OF LIPASE ENZYME ON THE RIPENING OF WHITE PICKLED CHEESE

The effect of addition of pregastric lipase enzyme on the accelerated ripening of white pickled cheese was investigated. Commercial pregastric lipase was added to milk before rennet addition at a level of 0,5, 8, 11 g per 100 L of milk and cheeses were made from this milk. Total solids, fat, total nitrogen, salt, titratable acidity, pH and free fatty acids (C₂-C_18:1) were analysed in the samples during 1–90 days of ripening period at 15 days intervals. Total solids, fat, total nitrogen, salt, titratable acidity, and pH of cheeses slightly increased during the ripening period. Free fatty acids and volatile free fatty acid contents in cheeses made from pregastric lipase added milk were affected by pregastric lipase and their contents were increased significantly (P<0.01) during the ripening period. Particularly, when cheese had a high level (11 g per 100 L milk) pregastric lipase, the amounts of butyric, caproic and caprylic acids in white pickled cheese were quite high. The relative amounts of volatile free fatty acids varied with storage time and pregastric lipase levels.     

Chymosin-mediated proteolysis, calcium solubilization, and texture development during the ripening of cheddar cheese

Full fat, milled-curd Cheddar cheeses (2 kg) were manufactured with 0.0 (control), 0.1, 1.0, or 10.0 μmol of pepstatin (a potent competitive inhibitor of chymosin) added per liter of curds/whey mixture at the start of cooking to obtain residual chymosin levels that were 100, 89, 55, and 16% of the activity in the control cheese, respectively. The cheeses were ripened at 8°C for 180 d. There were no significant differences in the pH values of the cheeses; however, the moisture content of the cheeses decreased with increasing level of pepstatin addition. The levels of pH 4.6-soluble nitrogen in the 3 cheeses with added pepstatin were significantly lower than that of the control cheese at 1 d and throughout ripening. Densitometric analysis of urea-PAGE electro-phoretograms of the pH 4.6-insoluble fractions of the cheese made with 10.0 μmol/L of pepstatin showed complete inhibition of hydrolysis of α_S1-casein (CN) at Phe₂₃-Phe₂₄ at all stages of ripening. The level of insoluble calcium in each of 4 cheeses decreased significantly during the first 21 d of ripening, irrespective of the level of pepstatin addition. Concurrently, there was a significant reduction in hardness in each of the 4 cheeses during the first 21 d of ripening. The softening of texture was more highly correlated with the level of insoluble calcium than with the level of intact α_S1-CN in each of the 4 cheeses early in ripening. It is concluded that hydrolysis of α_S1-CN at Phe₂₃-Phe₂₄ is not a prerequisite for softening of Cheddar cheese during the early stages of ripening. We propose that this softening of texture is principally due to the partial solubilization of colloidal calcium phosphate associated with the para-CN matrix of the curd.