Influence of milk pasteurization and scalding temperature on the volatile compounds of Malatya, a farmhouse Halloumi-type cheese

Lait 87 (2007) 39–57
© INRA, EDP Sciences, 2007
39
DOI: 10.1051/lait:2006025
Original article
Influence of milk pasteurization and scalding
temperature on the volatile compounds of
Malatya, a farmhouse Halloumi-type cheese
Ali A. HAYALOGLUa*, Elizabeth Y. BRECHANYb
a Department of Food Engineering, Inonu University, 44280 Malatya, Turkey
b Food Quality and Safety Group, Hannah Research Institute, Ayr, KA6 5HL, UK
Received 20 July 2006 – Accepted 28 November 2006
Abstract – Malatya cheese, a farmhouse Halloumi-type cheese, was made from raw or pasteurized
milk and the curds were scalded in hot whey at 60, 70, 80 or 90 oC. After ripening for 30 or 90 d,
the cheeses were analyzed for characterization of volatile composition. One hundred and two vola-
tile compounds including 11 acids, 13 esters, 15 ketones, 6 aldehydes, 26 alcohols, 2 lactones, 5 sul-
fur compounds, 5 terpenes and 19 miscellaneous compounds were identified using solid phase
micro extraction and gas chromatography-mass spectrometry. The use of raw milk in the manufac-
ture enriched the volatile profile of the cheese and the majority of volatiles were more abundant in
raw milk cheeses than in pasteurized milk cheeses. The cheeses made with raw milk contained
higher levels of acids, esters and lactones and lower levels of aldehydes and sulfur compounds than
did the cheeses made from pasteurized milk. Principal component analysis (PCA) was applied to
simplify interpretation of the GC-MS data and distinguished the raw and pasteurized milk cheeses
on the plot. The samples were also classified based on scalding temperature by PCA, but no regular
distribution was observed. The results suggest that the pasteurization of cheese milk had a greater
effect on volatile composition of cheese than scalding temperature of the curd.
pasteurization / raw milk / Malatya cheese / volatile compounds / scalding / aroma
?? – ?????????????????? Halloumi ??——Malatya ??????
??????? Malatya ?????? Halloumi ??????????????????
???????? 60? 70? 80 ? 90 °C ?????? 3 min????? 30 d ? 90 d ??
??????????????????????? GC/MS ??????? 102 ????
?????????? 11 ????? 13 ??????? 15 ??????? 6 ?????
?? 26 ??????? 2 ???? 5 ????? 5 ???? 19 ???????????
???????????????????????????????????????
???????????????????????????????????????
???????????????? (PCA) ? GC-MS ????????????????
???????????????????????????????????? PCA ?
???????????????????????????????????????
????????????????????????????
???? / ??? / Malatya ?? / ????? / ?? / ????
* Corresponding author (????): ahayaloglu@inonu.edu.tr
Article published by EDP Sciences and available at http://www.edpsciences.org/lait or http://dx.doi.org/10.1051/lait:2006025

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40
A.A. Hayaloglu, E.Y. Brechany
Résumé – Influence de la pasteurisation du lait et de la température de cuisson sur les compo-
sés volatils du Malatya, fromage fermier de type Halloumi. Du Malatya, un fromage fermier de
type Halloumi, a été fabriqué à partir de lait cru et de lait pasteurisé, et les caillés obtenus ont été
cuits dans du lactosérum chauffé à 60, 70, 80 ou 90 °C. Après 30 ou 90 jours d’affinage, la compo-
sition en volatils des fromages a été caractérisée. Cent deux composés volatils incluant 11 acides,
13 esters, 6 aldéhydes, 26 alcools, 2 lactones, 5 composés soufrés, 5 terpènes et 19 composés divers
ont été identifiés par micro-extraction en phase solide et chromatographie gazeuse couplée à la spec-
trométrie de masse (CG-MS). L’utilisation du lait cru pour la fabrication a abouti à un profil en vola-
tils plus riche et la majorité des volatils étaient présents en quantité plus importante dans les froma-
ges au lait cru par rapport aux fromages au lait pasteurisé. Les fromages au lait cru contenaient des
teneurs plus élevées en acides, esters et cétones, et des teneurs moins élevées en aldéhydes et com-
posés soufrés. Une analyse en composante principale (ACP) a permis de simplifier l’interprétation
des données de CG-MS et de différencier les fromages au lait cru des fromages au lait pasteurisé.
Les échantillons ont également été classifiés sur la base de la température de cuisson par ACP, mais
aucune distribution régulière n’a pu être observée. Ces résultats suggèrent que la pasteurisation du
lait de fabrication a un effet sur la composition en volatils plus marqué que celui de la température
de cuisson du caillé.
pasteurisation / lait cru / Malatya / composé volatil / cuisson du caillé / arôme
1. INTRODUCTION
prior to cheese making had an effect on mi-
crobial flora, proteolysis, free amino acids,
Cheese ripening is a complex and dy-
free fatty acids, volatile fractions and sen-
namic biochemical process that includes
sory characteristics [6, 12, 17, 26, 31, 39].
protein breakdown, fat hydrolysis and lac-
However, heat treatment of milk prior to
tose metabolism [25]. Hydrolysis of casein
cheese making is an essential process in
by proteolytic enzymes produces peptides
many cheeses due to the presence of unde-
and free amino acids. These play a critical
sirable microorganisms which causes some
role in the development of cheese flavour.
defects in texture and flavour. In addition,
Many volatile compounds which contribute
it can ensure the hygienic and standard
to the characteristic aroma and flavour oc-
quality of cheese, the ripening at higher
cur during the ripening of cheeses. Some
temperature and the reduction of some risks
factors affect the composition of volatile
including blowing caused by butyric fer-
fractions in cheese such as animal feeding,
mentation, control over lactic acid produc-
the types of milk, coagulant, starter or sec-
tion and off-flavours [30].
ondary starters, heat treatment of milk, rip-
Malatya, a farmhouse Halloumi-type
ening time and temperature [7, 12, 14, 31,
cheese, is traditionally made from raw
39]. Heat treatment of milk alters the fla-
vour profile of cheese due to a decrease in
ewe’s or cow’s milks or their appropriate
the number of non-starter lactic acid bacte-
mixtures and no starter culture is employed.
ria (NSLAB) and possibly inactivation of
The traditional method is still used in farms
indigenous milk enzymes [15, 40]. Heat
in small scale and villages. Recently, some
treatment causes delaying in the flavour de-
cheese makers used the pasteurization proc-
velopment in cheese. Lau et al. [22] re-
ess in its manufacture and added a starter
ported that a cheese made from pasteurized
culture to standardize the production and to
milk took twice as long as that made from
eliminate undesirable microorganisms. The
raw milk to develop the same flavour inten-
characteristics of this type of cheeses are the
sity and lower levels of soluble nitrogen
scalding process which produces an elastic
and free amino acid were obtained in cheese
and compact texture after the pressing of
made from pasteurized milk. The native mi-
curd at 80–90 °C. So, a second heat treat-
croorganisms and indigenous milk en-
ment is applied in the manufacture of
zymes are main contributors for the
Malatya cheese and the method of manu-
formation of the characteristic aroma com-
facture influences the physical, chemical
ponents in cheese. Heat treatment of milk
and sensory characteristics of the cheese.

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Volatile compounds in Malatya cheese
41
A number of volatile components be-
means of dipping their wheys and then the
longing to the chemical groups acids, es-
cheese blocks were re-pressed between the
ters, aldehydes, ketones, alcohols, sulfur
same wooden blocks for 3 min and then im-
compounds and other aromatic hydrocar-
mediately cooled to room temperature.
bons have been identified in different
Then, the cooled blocks were immersed in
cheeses [27–29, 36]. To the authors’ knowl-
brine (10% NaCl) and ripened for 90 d at 6–
edge, no previous studies were carried out
8 °C.
to identify the volatile compounds contrib-
uting to the characteristic volatile profiles
2.2. Chemical analysis
of Malatya cheese; consequently, a study
would be useful for the characterization of
Cheeses were analyzed in duplicate for
this cheese which is currently manufactured
moisture, fat, total protein, salt, pH and ti-
both from raw and pasteurized milk. The
tratable acidity as described in Hayaloglu
objective of the study was to investigate the
et al. [16]. Statistical evaluation of the
influence of pasteurization prior to cheese
chemical data was analyzed by ANOVA
making and scalding temperatures on vol-
with significant differences for P < 0.05
atile composition of Malatya cheese during
using SPSS package program version 9.0
ripening.
for Windows (SPSS Inc., Chicago, IL).
2. MATERIALS AND METHODS
2.3. Analysis of volatile components
in cheese using Solid Phase
2.1. Cheese-making
Microextraction (SPME)
Malatya cheese was made in duplicate
Cheese samples were sliced, frozen in
using both raw and pasteurized cow’s milk
liquid nitrogen, pulverized into small gran-
in a local dairy plant (Karlidag Dairy Prod-
ules and stored in glass bottles in a freezer
ucts, Malatya, Turkey). A volume of 200 L
at –20 °C. Samples were analyzed within
raw cow’s milk was used in the manufac-
max. 14 d. A 3-g portion of sample was then
ture of Malatya cheese with 100 L of the
placed in a 15-mL vial and allowed to equil-
milk used to make raw milk cheese (C
ibrate at 40 °C for 30 min. Essentially,
cheeses) and the rest pasteurised at 72 °C
extraction is achieved by injecting a
for 30 s and used for the manufacture of pas-
75-µm Carboxen–Polydimethylsiloxane fiber
teurized milk cheeses (P cheeses). After
(Sigma-Aldrich, Poole, England) into the
pasteurization, the milk was cooled to
vial and exposing to the headspace for
32 °C and the commercial culture consist-
30 min at 40 °C. The fiber was positioned
ing of selected strains of Lc. lactis ssp. lactis
at 3.0 scale units in each run. Desorption of
and Streptococcus thermophilus (Sacco,
the extracted volatiles was carried out on an
srl, Cadorago, Italy) was added at the man-
Agilent 5890 Gas Chromatography-5972
ufacturer’s recommended dose and held for
Mass Spectrometry System (Agilent Tech-
30–45 min. Both C and P cheeses were co-
nologies, UK Ltd, Cheshire, UK) run in
agulated using commercial calf rennet
splitless mode. During desorption the fiber
(>85% chymosin, REN–NA®, Mayasan,
remained in the injector for 2 min at a tem-
Istanbul, Turkey) at the level of 15 g·100 L–1.
perature of 250 °C, with helium as the car-
The coagulation took place at 32 °C for
rier gas at a flow rate of 1.0 mL·min–1. The
45 min. Following coagulation, the curd
components were separated on an Agilent
was cut and stirred for about 30 min, and
FFAP column, 50 m × 0.2 mm × 0.33 µm
transferred into cloth bags and then left for
(Crawford Scientific, Lanarkshire, Scot-
30 min to drain its whey with no pressing.
land). The oven was held at 40 °C for 2 min
The bags which contain approx. 250 g of
(desorption period), then ramped at 5 °C
curd were tied up and moulded as a ball, and
per min to 70 °C, which was held for 1 min.
then they were pressed between two
The temperature was then raised at 10 °C
wooden blocks for 2 h. The cheeses were
per min to 240 °C to give a run time of
scalded at 60, 70, 80 or 90 °C for 3 min by
30 min. The mass spectrometer was set to

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42
A.A. Hayaloglu, E.Y. Brechany
Table I. Chemical composition and pH of Malatya cheese made from raw (C) and pasteurized (P)
milk after 1 d of ripening. Codes 60, 70, 80 or 90 refer to scalding temperature of the curd (°C).
Cheeses
Titratable
pH
Total solid
Salt
FDM2
Total protein
acidity1
(%)
(%)
(%)
(%)
C60
0.21 ± 0.08ab
6.02 ± 0.5a
39.85 ± 0.55a 2.70 ± 0.0a
42.03 ± 0.05a 14.03 ± 0.32ab
C70
0.14 ± 0.0a
6.03 ± 0.42a
40.20 ± 0.30a 2.81 ± 0.0a
41.64 ± 2.79a 15.04 ± 014bcd
C80
0.22 ± 0.09ab
6.01 ± 049a
38.79 ± 0.70a 2.70 ± 0.0a
45.74 ± 1.10a 16.20 ± 0.28d
C90
0.23 ± 0.07ab
5.96 ± 0.39a
38.90 ± 1.55a 2.70 ± 0.0a
49.48 ± 0.04a 15.68 ± 0.05d
P60
0.37 ± 0.03b
5.62 ± 0.16b
39.22 ± 0.17a 1.93 ± 0.0a
44.60 ± 2.35a 13.74 ± 0.50a
P70
0.39 ± 0.01b
5.57 ± 0.03b
39.20 ± 0.75a 1.76 ± 0.0a
44.68 ± 2.13a 14.94 ± 0.69bcd
P80
0.30 ± 0.02ab
5.81 ± 0.06ab
40.75 ± 2.55a 2.70 ± 0.0a
41.72 ± 0.15a 14.25 ± 0.0abc
P90
0.29 ± 0.04ab
5.81 ± 0.03ab
40.22 ± 0.52a 2.46 ± 0.0a
42.33 ± 5.52a 15.36 ± 0.01cd
Mean ± SD of duplicate determination in two cheesemaking trials. Means in the same column followed
by different letters differ (P < 0.05).
1 Titratable acidity expressed as g lactic acid/100 g cheese.
2 FDM: fat-in-dry matter.
record 33–450 atomic mass units, threshold
and age. To simplify interpretation of the re-
1000, at a sampling rate of 1.11 scans per s.
sults, principal component analysis (PCA)
was performed using the varimax rotation
2.4. Data analysis of SPME
between the aroma characters of the
cheeses on the ANOVA results. PCA was
Components were identified using the
carried out using The Unscrambler v9.6
data obtained from the mass spectrometer
free-trial version (CAMO, Software AS,
in full scan mode. A database was then set
Oslo, Norway).
up to quantitate relative amounts of each.
The database was constructed using se-
lected ion monitoring with specific ions se-
3. RESULTS AND DISCUSSION
lected in order to allow quantitation of
co-eluting peaks. Response factors were
3.1. Chemical composition
not used in the quantitation of the samples
as these would require the determination of
The chemical composition and pH of
rate of release from the cheese into the
Malatya cheese at 1st d of ripening are
headspace, and the efficiency of extraction
shown in Table I. No significant differences
of each component. Thus actual concentra-
were found between cheeses in total solids,
tions of the components in the cheese are
salt and fat-in-dry matter. However, a
not known but for the purpose of this project
higher level of titratable acidity and lower
comparative values were used to show dif-
pH values were found in the cheeses made
ferences between the varying treatments.
from pasteurized milk with a starter culture
Instead the data was in the form (Area of
(P < 0.05). The addition of starter culture to
peak/105) and was normalized to a weight
the pasteurized milk resulted in signifi-
of 1 g sample. This comparative data was
cantly lower pH in pasteurized milk cheeses
then analyzed using ANOVA whereby the
(P) in comparison to raw milk cheeses (C).
mean response of the data, transformed to
The gross composition of the cheese sam-
give the square root (SQRT), was calcu-
ples at the beginning of the ripening period
lated. ANOVA of the SQRT transformed
are in the normal ranges for a salted cheese.
data was carried out using Minitab Statisti-
These results are in accordance with those
cal Software version 13 (Minitab Ltd., Cov-
of Ozer et al. [34] for Urfa cheese and
entry, England) on the basis of cheese type
Kahyaoglu and Kaya [21] for Gaziantep

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Volatile compounds in Malatya cheese
43
Table II. Concentrations of fatty acids in Malatya cheese made from raw (C) and pasteurized (P)
milk during ripening. Codes 60, 70, 80 or 90 refer to scalding temperature of the curd (°C). The
results were expressed as SQRT [Area/105] from triplicate analysis of each cheese.
Fatty acid
Age (d)
Cheeses
ANOVA
C60
C70
C80
C90
P60
P70
P80
P90
P-type P-age
Formic acid
30
1.27
1.58
1.92
2.10
3.14
2.58
2.40
1.98
NS
**
90
1.37
1.51
1.38
1.15
1.70
1.25
1.13
1.32
Ethanoic acid
30
16.93
18.86 22.62
23.38 23.16 21.65 22.04 17.67
NS
**
90
23.96
31.37 28.39
26.36 25.00 20.63 18.75 23.11
Propanoic 30
1.25
1.20
1.37
1.64
1.58
0.99
0.95
0.80
***
***
90
3.88
4.08
4.39
3.27
1.37
1.30
1.31
1.32
acid
2-Methyl
30
1.19
1.57
1.84
1.89
1.32
1.31
1.16
1.14
**
***
propanoic acid
90
4.79
3.20
3.53
2.43
2.09
2.01
2.06
1.93
Butanoic acid
30
12.99
13.61 15.15
14.77
7.16
7.25
6.47
5.22
***
***
90
21.76
25.03 23.91
22.30
9.50
7.90
7.66
7.71
2-Methyl
30
0.71
0.61
0.71
0.80
0.63
0.58
0.50
0.48
**
***
butanoic acid
90
2.41
1.79
2.01
1.36
1.02
0.93
0.96
0.89
3-Methyl
30
2.67
2.96
3.69
3.90
3.06
3.36
3.04
2.87
*
***
butanoic acid
90
6.96
6.36
6.34
4.97
4.30
4.24
4.54
3.91
Pentanoic
30
1.73
1.85
1.83
1.81
1.20
1.20
1.08
0.87
**
**
acid
90
2.27
2.67
2.43
2.35
1.28
1.20
1.19
1.10
Hexanoic acid
30
12.45
11.53 11.40
11.98
7.05
6.08
5.30
4.56
**
**
90
16.08
18.44 16.59
17.49
6.86
6.03
5.76
4.52
Octanoic acid
30
5.55
5.52
4.74
5.42
4.02
3.34
2.71
2.61
**
NS
90
5.85
6.54
6.89
7.22
2.75
2.85
2.84
1.96
Decanoic acid
30
1.96
2.03
2.12
2.36
1.84
1.52
1.34
1.22
**
NS
90
2.02
2.20
2.39
2.40
1.21
1.27
1.22
0.89
Total
30
58.70
61.33 67.37
70.05 54.14 49.86 46.98 38.21
90
91.33 103.18 98.25
91.29 57.07 49.60 47.42 48.66
* P < 0.01; ** P < 0.001; *** P < 0.0001; NS: non significant.
cheese; these cheeses are scalded and rip-
previously been conducted in Malatya
ened in brine like Malatya cheese.
cheese or other cheeses where scalding is
carried out on the curd in hot whey. In the
3.2. Volatile composition
present study, the use of pasteurised milk in
One hundred and two compounds were
the manufacture and ripening time has sig-
identified in the volatile fractions of
nificantly influenced the volatile fraction in
Malatya cheese including 11 fatty acids, 13
Malatya cheese. Some of the volatile com-
esters, 15 ketones, 6 aldehydes, 26 alcohols,
pounds (forty) were significantly influ-
2 lactones, 5 sulfur compounds, 5 terpenes
enced by using pasteurized milk in the
and 19 miscellaneous compounds. The
manufacture or by scalding the curd in hot
compounds identified from the cheeses
whey and sixty-three compounds were sig-
were listed by chemical group in Tables II–X.
nificantly influenced by cheese age
Identification of volatile fraction has not
(P < 0.01).

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44
A.A. Hayaloglu, E.Y. Brechany
3.2.1. Fatty acids
terness of amines [35]. Table III shows the
mean concentrations of esters identified in
Fatty acids are one of the main chemical
Malatya cheeses during ripening. Ethyl es-
groups in the volatile fraction of Malatya
ters (seven esters) are the principal esters in
cheese (Tab. II). Ethanoic and propanoic
the cheese samples and the other esters were
are produced by the fermentation of lactose
methyl, propyl and butyl (Tab. III). The
or lactic acid; in contrast, 2-methyl propa-
highest level of ethyl esters in the cheeses
noic, 2- and 3-methyl butanoic acids are
can be correlated with higher concentra-
produced by the metabolisms of Val, Leu
tions of primary alcohols and fatty acids
and Ile amino acids, respectively [29, 40].
[11]. Concentration of ethyl acetate, the
Use of pasteurized milk in the production of
most abundant of esters, was higher in raw
Malatya cheese and scalding the curd in hot
milk cheese on 30 d of ripening and its con-
whey have significantly influenced all fatty
centration was the same in both raw and
acids present in the cheese except formic
and ethanoic acids. Concentration of the
pasteurized milk cheeses. Methyl lactate,
fatty acids with the exception of octanoic
propyl hexanoate and 3-methylbutyl bu-
and decanoic acids changed with age. For-
tanoate were not detected in pasteurized
mation of the fatty acids in raw or pasteur-
milk cheeses, while ethyl propionate was
ised milk cheeses exhibited a different trend
not identified in raw milk cheeses. Ethyl bu-
during ripening. On 90 d of ripening, raw
tanoate, ethyl hexanoate, ethyl octanoate
milk cheeses had the highest concentrations
and ethyl lactate were identified at the high-
of ethanoic, propanoic, 2-methyl propa-
est concentrations in raw milk cheeses and
noic, butanoic, 2-methyl butanoic, 3-methyl
their concentrations increased significantly
butanoic, pentanoic, hexanoic, octanoic
during ripening.
and decanoic acids probably due to numer-
ous other microflora could be involved in
cheese lipolysis. The results obtained are in
3.2.3. Ketones
agreement with studies by Buchin et al. [6]
and Shakeel-Ur-Rehman et al. [38] who
A total of 15 ketones were identified in
found that the concentration of acids was
Malatya cheeses made from raw or pasteur-
higher in raw milk cheese than those of pas-
ized milk. Methyl ketones are principal
teurised milk cheese during ripening. Pas-
compounds in blue cheeses and are formed
teurization of cheese milk had a greater
by enzymatic oxidation of free fatty acids
effect than scalding the curd in hot whey on
to ?-ketoacids and their consequent decar-
the formation of acids in Malatya cheese. In
boxylation to methyl ketones [11, 25], con-
general, the concentration of the fatty acids
tributing to the pungent aroma [31]. The
decreased as scalding temperature increased;
majority of ketones identified in Malatya
however, a strong correlation or relationship
cheeses were not different between cheeses
between scalding temperature and concen-
made from raw or pasteurized milk except
tration of the fatty acids cannot be found.
2-propanone, diacetyl and 2,3-pentanedi-
The concentration of formic and ethanoic ac-
one. Major ketones were 2-propanone, 2-
ids were not affected by heating of the curd
butanone, 2-pentanone, 2-heptanone, 3-
in hot whey. These compounds are pro-
hydroxy 2-butanone (acetoin) and diacetyl
duced by several metabolic pathways such
(Tab. IV) in the cheeses. Diacetyl (2,3-bu-
as lactose or butyric acid fermentation, ca-
tanedione) is one of the most important ke-
tabolism of some amino acids or hydrolysis
tones and it denotes a buttery and nutty
of glycerides [29]. Butanoic (butyric) acid
flavours in cheese [29]. Diacetyl is pro-
has a strong effect on cheese flavour, since
duced by metabolisms of lactose and citrate
it is found only in milk fat and is described as
by cit+ Lactococcus lactis ssp. lactis and
having a cheesy and sweaty odour.
Leuconostoc species [11]. Changes in ke-
tone concentration showed different trends
3.2.2. Esters
during ripening. That is, some fluctuations
Esters contribute to cheese flavour by
were observed during ripening. The
minimizing sharpness of fatty acids and bit-
concentration of the majority of methyl

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Volatile compounds in Malatya cheese
45
Table III. Concentrations of esters in Malatya cheese made from raw (C) and pasteurized (P) milk
during ripening. Codes 60, 70, 80 or 90 refer to scalding temperature of the curd (°C). The results
were expressed as SQRT [Area/105] from triplicate analysis of each cheese.
Ester
Age (d)
Cheeses
ANOVA
C60
C70
C80
C90
P60
P70
P80
P90
P-type P-age
Methyl
30
0.35
0.35
0.34
0.41
0.35
0.39
0.48
0.54
NS
NS
acetate
90
0.37
0.34
0.39
0.31
0.50
0.53
0.55
0.63
Methyl
30
ND
ND
ND
ND
ND
ND
ND
ND
***
***
lactate
90
1.59
1.53
1.84
1.83
ND
ND
ND
ND
Ethyl
30
11.34
10.93
10.99
11.24
7.22
7.24
9.78
8.84
NS
NS
acetate
90
8.17
11.26
10.66
11.28
10.62
10.42
8.81
8.92
Ethyl
30
ND
ND
ND
ND
ND
ND
ND
ND
***
***
propanoate
90
ND
ND
ND
ND
1.20
1.09
1.07
1.04
Ethyl
30
4.66
4.19
4.32
4.11
1.95
2.25
2.73
2.57
*
*
butanoate
90
3.78
4.92
4.72
5.32
3.66
3.36
2.92
3.09
Ethyl
30
3.18
2.77
2.36
2.41
1.39
1.16
1.11
0.93
**
**
hexanoate
90
3.78
4.62
4.24
4.93
1.27
1.52
1.13
1.06
Ethyl
30
1.37
1.45
0.98
1.32
1.00
0.74
0.43
0.52
**
**
octanoate
90
1.85
2.13
2.34
2.54
0.81
0.79
0.72
0.49
Ethyl
30
0.55
0.59
0.52
0.58
0.48
0.69
1.00
0.78
NS
NS
decanoate
90
0.66
0.76
0.84
0.87
0.39
0.42
0.41
0.33
Ethyl
30
1.20
1.41
1.74
1.89
1.80
1.74
1.64
1.32
**
***
lactate
90
2.90
6.44
4.24
4.15
2.14
1.50
1.31
1.81
Propyl
30
1.25
1.47
1.19
1.16
1.14
1.03
1.38
1.33
NS
NS
acetate
90
1.33
1.94
1.76
1.84
1.03
1.04
1.13
0.95
Propyl
30
0.91
0.59
0.00
ND
ND
ND
ND
ND
*
NS
hexanoate
90
0.09
0.34
0.38
ND
ND
ND
ND
ND
3-Methylbutyl
30
2.07
1.40
1.31
1.77
1.26
1.22
1.37
1.23
NS
*
acetate
90
2.37
2.83
3.46
2.84
1.84
1.64
1.58
1.83
3-Methylbutyl
30
0.68
0.49
ND
ND
ND
ND
ND
ND
*
**
butanoate
90
ND
ND
ND
ND
ND
ND
ND
ND
Total 30
27.56
25.64
23.75
24.88
16.57
16.46
19.91
18.05
90
26.89
37.11
34.85
35.89
23.46
22.32
19.63
20.13
* P < 0.01; ** P < 0.001; *** P < 0.0001; NS: non significant; ND: not detected.
ketones decreased during ripening, while
teurized cheeses milk. This correlated well
the concentration of 2-propanone and 2-
with studies by Bintis and Robinson [3]
undecanone increased with ripening time in
who found higher levels of 3-hydroxy 2-
all cheeses. Interestingly, 1-hydroxy 2-
butanone and diacetyl in fresh Feta cheese
propanone was not identified in pasteurized
than those of 60-d old Feta cheeses, proba-
milk cheeses either at d 30 or 90; however,
bly due to the action of starters, while they
1-hydroxy 2-propanone and 2,3-pentanedi-
declined during ripening. Raw milk cheeses
one were not determined in 90-d old raw
contained the highest levels of 2,3-pentane-
milk cheeses. Concentrations of 3-hydroxy
dione at 30 d of ripening; however, it was not
2-butanone and diacetyl were higher in raw
identified at 90 d of ripening. The concen-
milk cheeses at 30 d but showed a marked de-
tration of 2,3-pentanedione in pasteurized
crease at 90 d as compared to the trend for pas-
milk cheese was half the amount of raw milk

---

46
A.A. Hayaloglu, E.Y. Brechany
Table IV. Concentrations of ketones in Malatya cheese made from raw (C) and pasteurized (P)
milk during ripening. Codes 60, 70, 80 or 90 refer to scalding temperature of the curd (°C). The
results were expressed as SQRT [Area/105] from triplicate analysis of each cheese.
Ketone
Age (d)
Cheeses
ANOVA
C60
C70
C80
C90
P60
P70
P80
P90
P-type P-age
2-Propanone
30
7.02
6.71
6.40
7.63
9.38
11.21
10.64
11.57
**
**
90
9.60
7.59
8.39
7.75
11.92
12.99
14.72
13.25
2-Butanone
30
10.23
10.01
9.07
11.59
15.31
9.90
10.52
10.33
NS
**
90
9.41
8.47
8.82
8.84
9.57
9.71
9.44
9.89
2-Pentanone
30
8.00
6.71
6.30
5.78
5.63
9.15
8.85
7.13
NS
*
90
5.09
4.75
5.41
6.83
6.72
7.15
6.31
6.62
2-Hexanone
30
1.01
0.97
0.81
0.93
0.92
1.43
1.19
1.12
NS
NS
90
0.75
0.78
0.82
1.04
1.01
1.08
0.97
1.03
2-Heptanone
30
7.97
7.66
6.14
8.07
8.44
15.25
10.96
8.82
NS
*
90
6.17
5.72
6.16
9.70
6.51
8.00
5.72
6.44
2-Octanone
30
0.75
0.60
0.39
0.51
0.58
1.25
0.83
0.76
NS
NS
90
0.50
0.45
0.63
0.71
0.45
0.60
0.70
0.41
2-Nonanone
30
2.94
2.92
2.08
2.77
3.25
5.32
3.62
3.18
NS
*
90
2.85
2.32
2.45
3.50
2.04
2.36
2.46
1.93
2-Decanone
30
0.35
0.35
0.12
0.29
0.28
0.21
ND
ND
NS
NS
90
0.21
0.10
0.20
0.26
ND
ND
ND
ND
2-Undecanone
30
0.45
0.49
0.42
0.49
0.46
0.51
0.41
0.41
NS
*
90
0.55
0.56
0.57
0.62
0.45
0.48
0.52
0.44
1-Hydroxy
30
1.49
1.57
1.68
1.78
ND
ND
ND
ND
***
***
2-propanone
90
ND
ND
ND
ND
ND
ND
ND
ND
3-Hydroxy
30
8.18
10.57
11.12
10.66
7.65
7.61
7.65
7.97
NS
***
2-butanone
90
2.76
2.71
2.29
2.98
6.14
4.66
5.19
5.37
3-Hydroxy
30
3.09
3.14
3.70
2.26
2.28
2.73
2.62
2.66
NS
***
2-pentanone
90
0.50
0.38
ND
0.33
1.44
0.97
1.09
1.19
2-Hydroxy
30
2.92
2.92
3.42
2.17
2.08
3.04
2.52
2.60
NS
***
3-pentanone
90
0.52
0.32
ND
ND
1.34
0.96
1.12
1.12
Diacetyl
30
13.80
13.72
15.62
12.29
7.74
9.19
9.50
9.30
*
***
90
4.57
5.72
5.82
7.58
6.80
6.71
7.12
6.53
2,3-Pentane-
30
6.77
6.18
7.25
4.37
2.32
2.84
3.03
3.09
**
***
dione
90
ND
ND
ND
ND
1.48
1.19
1.72
1.45
Total
30
74.96
74.51
74.49
71.57
66.31
79.62
72.33
68.94
90
43.45
39.88
41.55
50.14
55.87
56.85
57.07
55.67
* P < 0.01; ** P < 0.001; *** P < 0.0001; NS: non significant; ND: not detected.
cheeses at 30 d of ripening, but their con-
tanedione in cheeses inoculated with ther-
centration markedly declined at 90 d. Imhof
mophilic cultures and suggested that it
et al. [19] detected high levels of 2,3-pen-
might be produced by metabolism of Ile.

---

Volatile compounds in Malatya cheese
47
Table V. Concentrations of aldehydes in Malatya cheese made from raw (C) and pasteurized (P)
milk during ripening. Codes 60, 70, 80 or 90 refer to scalding temperature of the curd (°C). The
results were expressed as SQRT [Area/105] from triplicate analysis of each cheese.
Aldehyde
Age (d)
Cheeses
ANOVA
C60
C70
C80
C90
P60
P70
P80
P90
P-type P-age
Acetaldehyde
30
1.32
1.37
1.25
1.33
2.34
2.29
2.57
2.47
*
***
90
3.06
2.33
3.10
2.03
3.26
4.14
3.30
3.47
2-Propenal
30
0.58
0.61
0.42
0.62
0.92
ND
ND
ND
**
*
90
1.20
1.35
1.21
1.00
ND
ND
ND
ND
2-Methyl
30
0.52
0.65
0.79
0.78
0.65
0.81
1.00
0.96
NS
*
propanal
90
0.52
0.51
0.62
0.55
0.57
0.72
0.58
0.58
2-Methyl
30
0.32
0.45
0.44
0.48
0.31
0.49
0.57
0.48
NS
NS
butanal
90
0.39
0.37
0.52
0.41
0.43
0.53
0.54
0.34
3-Methyl
30
2.71
3.30
4.05
4.25
3.11
4.40
6.24
4.49
NS
***
butanal
90
1.06
0.95
1.35
1.01
1.20
1.12
1.05
1.36
Benzaldehyde
30
1.53
1.50
0.87
1.11
1.38
1.55
1.27
1.28
NS
NS
90
1.26
1.26
1.49
1.64
1.06
1.21
1.52
1.09
Total
30
6.97
7.87
7.82
8.57
8.71
9.52 11.65
9.68
90
7.48
6.76
8.27
6.64
6.51
7.72
6.99
6.83
* P < 0.01; ** P < 0.001; *** P < 0.0001; NS: non significant; ND: not detected.
3.2.4. Aldehydes
Emmental [5]. Benzaldehyde is formed in
cheese by ?-oxidation of phenyl acetalde-
Six aldehydes were identified in Malatya
hyde which is derived from Phe via
cheeses (Tab. V) and are produced by the
the Strecker reaction or ?-oxidation of
catabolism of fatty acids or amino acids via
cinnamic acid [25]. The concentration of
decarboxylation or deamination. Alde-
benzaldehyde was not influenced by pas-
hydes are transitory compounds and do not
teurization and ripening processes.
accumulate in cheese because they are
transformed rapidly to alcohols or to cor-
3.2.5. Alcohols
responding acids [10, 23]. No significant
differences in concentrations of 2-methyl-
The cheeses made from raw milk con-
propanal, 2-methylbutanal and 3-methylb-
tained higher levels than those of the
utanal branched-chain aldehydes were
cheeses made from pasteurized milk for
found among the cheeses made from raw or
most of the alcohols, especially after 90 d
pasteurized milk. These aldehydes are pro-
of ripening (Tab. VI). The concentrations of
duced from Val, Ile and Leu, respectively,
1-propanol, 2-propen-1-ol, 3-methyl 1-
by Strecker degradation or transamination
butanol, 3-methyl 2-buten-1-ol, 2-propanol,
and are responsible for unclean and harsh
2-butanol, 2-pentanol, 2-methoxy ethanol
flavours in Cheddar cheese [10]. The most
and phenethyl alcohol were significantly
abundant aldehyde was 3-methylbutanal in
higher in raw milk cheeses, suggesting the
30-d old cheeses; however, its concentra-
pasteurization process negatively influ-
tion decreased at 90 d and acetaldehyde was
enced the production of alcohols in cheese
the highest in 90-d old cheeses. The con-
during ripening. Primary alcohols such as
centration of acetaldehyde in the cheeses
1-propanol, 1-butanol, 1-pentanol, 1-hexa-
increased during ripening as observed in
nol, 1-heptanol, 1-octanol are produced
other types of cheese such as Roncal [32],
mainly by the reduction of aldehydes and

---

48
A.A. Hayaloglu, E.Y. Brechany
Table VI. Concentrations of alcohols in Malatya cheese made from raw (C) and pasteurized (P)
milk during ripening. Codes 60, 70, 80 or 90 refer to scalding temperature of the curd (°C). The
results were expressed as SQRT [Area/105] from triplicate analysis of each cheese.
Alcohol
Age (d)
Cheeses
ANOVA
C60
C70
C80
C90
P60
P70
P80
P90
P-type P-age
Ethanol
30
37.89 36.73 40.02 40.24 38.03 36.76 40.02 38.99
NS
**
90
29.07 34.89 32.20 31.07 39.92 35.81 33.58 42.59
1-Propanol
30
3.95
4.04
4.48
6.14
6.43
3.47
4.11
4.20
**
***
90
9.18 10.35
8.78
8.64
3.12
3.32
3.34
3.62
2-Propen-1-ol
30
0.57
0.85
0.70
1.35
1.31
0.57
0.55
ND
***
***
90
2.31
3.04
2.89
3.24
ND
ND
ND
ND
2-Methyl
30
1.67
3.11
3.23
3.83
1.52
1.54
1.69
1.66
NS
***
1-propanol
90
4.55
4.39
5.62
3.97
4.49
6.35
6.60
4.56
1-Butanol
30
4.50
4.74
3.83
3.70
3.61
3.78
4.45
3.88
NS
***
90
3.35
3.57
3.54
3.31
2.58
2.79
3.00
3.15
2-Methyl
30
2.99
3.81
3.90
4.34
3.30
3.44
3.64
3.44
NS
***
1-butanol
90
6.55
6.56
7.44
6.04
5.51
6.13
6.20
5.36
3-Methyl
30
7.84 10.17 10.63 11.86
8.96
9.35
9.86
9.44
*
***
1-butanol
90
15.85 16.10 17.21 14.81 12.33 12.94 13.24 12.14
3-Methyl
30
1.20
1.33
1.38
1.39
1.35
1.35
1.32
1.22
NS
**
3-buten-1-ol
90
2.27
3.03
2.27
2.05
1.91
1.59
1.56
1.94
3-Methyl
30
0.90
0.88
0.87
0.98
1.22
1.01
0.94
0.80
**
***
2-buten-1-ol
90
1.92
2.64
2.39
2.38
1.19
1.01
1.00
1.10
1-Pentanol
30
1.59
1.67
1.55
1.56
1.45
1.63
1.79
1.61
NS
NS
90
1.40
1.25
1.48
1.35
1.86
1.69
1.76
1.82
1-Hexanol
30
2.29
2.53
2.10
2.22
2.12
2.66
2.57
2.30
NS
NS
90
2.27
2.34
2.11
2.31
2.05
1.96
2.06
2.06
2-Ethyl
30
1.78
2.06
1.68
1.97
2.23
2.47
1.76
1.44
NS
*
1-hexanol
90
2.03
2.20
2.06
2.58
2.20
2.35
2.52
2.31
1-Heptanol
30
0.57
0.57
0.53
0.58
0.54
0.54
0.49
0.47
NS
*
90
0.64
0.65
0.62
0.72
0.59
0.59
0.61
0.49
1-Octanol
30
0.81
0.95
1.02
1.22
0.88
0.65
0.65
0.54
NS
**
90
0.56
0.55
0.51
0.60
0.45
0.50
0.55
0.41
2-Propanol
30
4.83
4.76
4.62
4.20
3.04
2.73
2.65
2.70
**
**
90
5.46
5.73
5.76
5.14
2.59
4.24
4.28
3.64
2-Butanol
30
4.37
4.52
4.47
7.13
5.50
3.47
3.86
3.61
***
***
90
20.18 22.76 20.87 19.11
4.48
4.96
5.14
5.52
2-Pentanol
30
3.17
2.82
2.72
2.70
2.39
2.35
2.42
2.28
*
***
90
4.68
5.66
5.12
4.86
3.06
2.75
2.96
3.56
2-Hexanol
30
0.89
0.66
0.62
0.61
0.51
0.56
0.56
0.53
NS
*
90
0.88
1.03
0.94
0.93
0.61
0.62
0.63
0.65

---