Greek protected designation of origin (PDO) cheeses are well-known for their quality and nutritive value. One hundred and twelve samples from 21 Greek PDO cheeses, a non-PDO and a potential PDO were ...analyzed for fatty acid (FA) profile and several physicochemical parameters including moisture, fat on dry matter (FDM), protein content, pH and salt content. Analyzed hard and semi-hard cheeses were Sfela, Kefalograviera, Kasseri, Ladotyri Mytilinis, Formaella Arachovas Parnassou, Graviera Agrafon, Graviera Kritis, Metsovone, Graviera Naxou, Mastelo, Batzos and San Michali. Soft, spread and whey cheeses included Kopanisti, Xynomyzithra Kritis, White cheese, Kalathaki Limnou, Manouri, Feta, Xygalo Siteias, Galotyri, Katiki Domokou, Pichtogalo Chanion and Anevato. The profile of 37 FAs combined with physiochemical properties was utilized to discriminate cheeses by label (cheese identity), cheese type (hard, semi-hard, soft, spread and whey) and milk type (cow, goat, sheep and combinations). The study found that Sfela had the highest salinity, Manouri the highest FDM and San Michali the highest content of proteins. Regarding FAs, the dominant ones in almost all cheeses were C
14:0
, C
16:0
, C
18:0
and
cis-9
C
18:1
. For classification concerning cheese identity, the most significant parameters were moisture, fat, C
18:2n-6c
, pH and salt. The most significant discriminants by cheese type were pH, moisture, FDM, salt and C
16:0
while C
10:0
, C
11:0
, C
14:1
, C
18:2n-6c
, C
20:0
, C
20:3n-6
and saturated FAs were more influential to separate by milk type. Results depict the FA profile of Greek PDO cheeses and show that in combination with physicochemical characteristics can be used as authenticity markers.
Greek Protected Designation of Origin (PDO) cheeses are characterised by high nutritional values and origin traits. The aim of the study was to determine the content of 65 elements, of Greek PDO ...cheeses, through inductively coupled plasma-mass spectrometry and examine the elemental metabolome as a potential authenticity marker. One hundred twelve samples from 21 PDO, one potential PDO and nine non-PDO cheeses were assessed. Discriminant analysis based on total fingerprinting was able to determine the geographic origin with 99.1% accuracy. The most significant variables of the model were Ce, Dy, Eu, Gd, Ho, La, Nd, Pr, Sm, Tb, Y, Yb, Pd, As, Ba, Co, Fe, Ga, Mo, Ni, Ti, Zr, Ca and P. The results demonstrate that elemental metabolomics can be successfully applied for cheese authentication. The elemental fingerprint could provide a reliable discrimination while rare earth elements are promising authenticity markers.
The proteolytic, lipolytic changes and the volatile profile of Xinotyri goat's cheese (an artisanal variety produced in the mountains of Naxos, a Greek island of the Aegean Sea) were studied during ...ripening. The cheese underwent very limited proteolysis; generally the WSN %TN and TCA-SN %TN contents remained stable, while the PTA-SN %TN content increased a little. Both β- and αs1-caseins were slightly degraded until the age of 22days and then remained stable. Free fatty acids (FFAs) content increased considerably during ripening and the most abundant FFAs were oleic, palmitic, myristic, stearic and capric acid. A total of 114 volatile compounds were detected. The most abundant group isolated at day 90 were alcohols followed by acids, ketones and esters, comprised 31.91%; 25.22%; 16.38%; and 15.54% of total compounds, respectively. Ethanol, acetic acid and hexanoic acid ethyl ester were at the highest level at all stages of ripening.
The headspace compounds of teleme cheese made from sheep's milk, goats' milk or mixture of sheep's and goats' milk (50:50) were analysed during ripening by static headspace gas chromatography-mass ...spectrometry. A total of 21 major compounds were identified, including aldehydes (7), alcohols (5), ketones (4), and acids (2). All types of cheeses contained approximately the same volatiles at different concentrations. The total volatile compounds (TVC) increased during ripening. Cheeses made from sheep's milk showed the highest level of TVC, whereas cheeses made from goats' milk showed the lowest one.
Water-soluble extracts of Teleme cheeses prepared from sheep, goat or cow milk and matured 120 days have been analysed for constituent peptides and proteins using proteomics. Techniques used include: ...(a) two-dimensional gel electrophoresis, with matrix-assisted laser desorption ionisation/mass spectrometry, (b) high-performance liquid chromatography in conjunction with mass spectrometry and Edman degradation and (c) tandem mass spectrometry. Gel electrophoresis showed species-specific differences in whey proteins and peptides from caseins but differences could not be resolved unambiguously using available databases. From high-performance liquid chromatography individual peaks were shown to be composed of a spectrum of peptides, with α-lactalbumin, β-lactoglobulin and a spectrum of casein-derived peptides most abundant. Tandem mass spectrometry detected casein-derived peptides with mass range 3000–1500
Da and identified species-specific differences. Overall, the peptide profile for Teleme cheese is typical of other cheeses and the species milk source can be resolved through proteomics.
As artisanal cheeses are gaining recognition during the last years by consumers, efforts
should be made to standardize their manufacture in order to produce safe products of high
and constant ...quality, supporting the local economy and spreading them outside the region
of origin. In this work, the biochemical and microbiological characteristics of Kefalotyri
cheese produced during summer in the mountains of Pindos using an artisanal cheesemaking procedure were studied. Sheep raw cheese milk was used without starter culture
addition for Kefalotyri cheese manufacture. At 90 days of ripening and storage (the date
that hard cheese can be sold in the market), its moisture was 40.4%, fat 28.8%, salt 4.1%
and proteins 23.3%. Butyric acid and 3methyl butanoic acid were the most abundant
volatile compounds found in this cheese. Mesophilic lactic acid bacteria and cocci were
dominated; high numbers of thermophilic lactic acid bacteria and cocci, enterococci and
Enterobacteriaceae were also present and the microbiological data revealed a rather
satisfactory hygienic sanitary condition of the cheeses.
Feta cheese was manufactured by using artisanal rennet from kids and lambs abomasa and allowed to ripen and store either in tin vessels or wooden barrels. In this study the effect of package type on ...composition, proteolysis, lipolysis and volatile compounds of cheeses was investigated. Feta cheese ripened and stored in wooden barrels had lower moisture contents than Feta cheese stored in tins. Also Feta in barrels had higher fat and lower salt contents than Feta cheeses stored in tins at 60days of storage, while at 180days the fat and salt contents were almost the same for all cheeses. Proteolysis and lipolysis (total free fatty acids) were similar in the cheeses and were not affected by the package type. The most abundant volatile compounds in all cheeses were the free fatty acids and especially acetic, butanoic, hexanoic, octanoic and decanoic acids. Other major compounds were ethanol and 3-methylbutanol. Feta cheese ripened and stored in wooden barrels had higher levels of acetone, butan-2-one, ethyl esters especially ethylacetate, ethylbutanoate, ethylhexanoate, ethyllactate, ethyloctanoate and ethyldecanoate, phenylethylacetate, 3-methylbutylacetate, 2-phenylethylacetate, as well as butan-1-ol, heptan-2-ol, phenylethanol and decanoic acid than Feta cheese ripened in tin vessels, during storage.
Teleme cheese was made from ovine, caprine and bovine milk with thermophilic, mesophilic, and mixed thermophilic–mesophilic cultures. Nine lots of cheese each time were made in order to study the ...physico-chemical and sensory changes of cheeses throughout ripening and storage up to 6 months. The rate of pH decrease was the fastest in cheeses made with the mesophilic culture and the slowest in cheeses made with the thermophilic culture, regardless of the kind of milk used. Moisture was higher in cheeses made from cows’ milk than in cheeses made from the other two kinds of milk. The highest fat content and yield were in cheeses made from ewes’ milk not being affected by starter culture used, the highest protein content was in cheeses made from goats’ milk whereas salt content was not affected by either the kind of milk or starter culture used. The use of mesophilic or mixed cultures resulted in cheeses of higher flavour scores than those of cheeses made with thermophilic culture. It is concluded that all three kinds of milk may be used in making Teleme cheese preferably by using a mesophilic or a mixed thermophilic and mesophilic starter culture.
Two types of Equations of State (EoS), which are characterized here as “simple” and “complex” EoS, are evaluated in this study. The “simple” type involves two versions of the Peng–Robinson (PR) EoS: ...the traditional one that utilizes the experimental critical properties and the acentric factor and the other, referred to as PR-fitted (PR-f), where these parameters are determined by fitting pure compound vapor pressure and saturated liquid volume data. As “complex” EoS in this study are characterized the EoS derived from statistical mechanics considerations and involve the Sanchez–Lacombe (SL) EoS and two versions of the Statistical Associating Fluid Theory (SAFT) EoS, the original and the Perturbed-Chain SAFT (PC-SAFT).
The evaluation of these two types of EoS is carried out with respect to their performance in the prediction and correlation of vapor liquid equilibria in binary and multicomponent mixtures of methane or ethane with alkanes of various degree of asymmetry. It is concluded that for this kind of systems complexity offers no significant advantages over simplicity. Furthermore, the results obtained with the PR-f EoS, especially those for multicomponent systems that are encountered in practice, even with the use of zero binary interaction parameters, indicate that this EoS may become a powerful tool for reservoir fluid phase equilibria modeling.
PDF
