International Journal of Food Science and Technology 2006, 41 (Supplement 1), 15–19
Original article
Antioxidant activity of Prunus mume extract in cooked chicken
breast meat
Seong-Chun Jo,1 Ki-Chang Nam,2 Byoung-Rok Min,2 Dong-Uk Ahn,2 Sung-Hwan Cho,3 Woo-Po Park4
& Seung-Cheol Lee1*
1
2
3
4
Division of Food Science and Biotechnology, Kyungnam University, Masan 631-701, Korea
Department of Animal Science, Iowa State University, Ames, IA 50011-3150, USA
Department of Food Science and Technology, Institute of Agriculture and Life Sciences, Gyeongsang National University, Jinju 660-701, Korea
Division of Food Science, Masan College, Masan 630-729, Korea
(Received 14 April 2005; Accepted in revised form 2 May 2006)
Summary
The antioxidant properties of methanolic extracts from the fruit of Prunus mume were determined in chicken
breast meat systems. When P. mume extract (PM) was added to chicken breast meat, 2-thiobarbituric acidreactive substances (TBARS) value at day 3 was decreased by about 45% of the control. PM did not affect
colour of chicken meat compared with the control. The amounts of volatile aldehydes and hydrocarbons
were significantly decreased by the addition of PM. Especially, hexanal was the most predominant volatile
compound in the control taking up almost more than 50% of the total volatiles and PM reduced the amount
into 26% of the control meat at 3 days.
Keywords
Antioxidant properties, chicken meat, extracts, Prunus mume.
Introduction
Activated oxygen species such as superoxide, hydrogen
peroxide, hydroxyl radical and singlet oxygen may cause
various disease state such as carcinogenesis, drug associated toxicity, inflammation, atherogenesis and aging in
aerobic organisms, as well as food deterioration (Horton
& Fairhurst, 1987; Halliwell et al., 1992; Ames et al.,
1993). Synthetic antioxidants, such as butylated hydroxyanisole, butylated hydroxytoluene and tertiary butylhydroquinone, have been widely used in foods for
preventing oxidation. However, the use of these synthetic
antioxidants in foods is discouraged because of their
potential toxicity (Buxiang & Fukuhara, 1997) and
carcinogenicity (Hirose et al., 1998). Natural antioxidants (Larson, 1988; Bae & Moon, 1997; Buxiang & Fukuhara, 1997; Yen et al., 1997), such as flavonoids, tannins,
coumarins, curcuminoids, xanthons, phenolics and terpenoids, have been attracted special interest because they
can remove free radicals, which may cause various
diseases, carcinogenesis and aging (Pokorny, 1991).
The fruit of Prunus mume has been used as a
traditional drug and healthy food in Asia. Currently, it
is widely consumed throughout the world because of its
possible health benefits (Utsunomiya et al., 2002). Some
polysaccharides of P. mume exhibited biological activ*Correspondent: Fax: 82 55 249 2995;
e-mail: sclee@kyungnam.ac.kr
doi:10.1111/j.1365-2621.2006.01234.x
2006 Institute of Food Science and Technology Trust Fund
ities such as mitogenesis, activation of the alternative
pathway of complement and activation of clot formation in human plasma (Dogasaki et al., 1994), benzyl
glucoside and chlorogenic acid from P. mume contributed to relieving the tension in model rats caused by ether
stress (Ina et al., 2004).
Precooked poultry meat products are highly susceptible to lipid oxidation and produce volatiles responsible
for warmed over flavour, and the use of antioxidants is
commonly required to retard oxidative quality deterioration during storage. The need for natural antioxidants is increasing in food and meat industries as
consumers demand safer and more natural additives.
Although a few plant extracts are widely used as safe
antioxidants, their activities are not as strong as
synthetic antioxidants such as butylated hydroxyanisole
(BHA) and butylated hydroxytoluene (BHT), and the
manufacturing cost is relatively high (Addis et al., 1992).
The objective of this research was to determine the effects
of P. mume extract (PM) on the lipid oxidation, volatile
compounds and colour changes in precooked aerobically
packaged chicken breast meat during refrigerated storage.
Experiment
Materials
Fresh fruits of P. mume were purchased from a local
market in Masan, Korea. 2-Thiobarbituric acid (TBA)
15
16
Antioxidant activity of Prunus mume for cooked chicken meat S-C. Jo et al.
was purchased from Sigma Chemical Co. (St Louis,
MO, USA) and methanol and ethanol were purchased
Duksan Pure Chemical Co. (Sungkok-Dong, Ansan,
Kyungkido, Korea).
Preparation of methanolic extract from P. mume
The fruits of P. mume were dried at 70 C for 24 h, then
was crushed by an electric mixer (Model FM-909T; Hanil
Electric, Seoul, Korea). The crushed P. mume was passed
through a 65 mesh sieve. Each 10 g of P. mume was
extracted with 100 mL of methanol in a shake incubator
overnight at room temperature and filtered through a
Whatman no. 1 filter paper. The residue was re-extracted
under the same conditions. The first and second extracts
were pooled and filtered through a Whatman nylon
membrane filter (0.2-lm; Millipore filtration kit, Millipore Co., Bedford, UK). The methanol in the filtrate was
evaporated using a rotary evaporator (Model Eyela
N-1000; Tokyo Rikakikai Co., Tokyo, Japan). The methanol extract of fruits of P. mume referred hereafter as PM.
Preparation of chicken breast patties
Chicken breasts from twelve different chickens were
randomly divided into three groups and each groups were
separately ground through a 3-mm plate and each ground
chicken meat group was used as a replication. Three
different chicken patty treatments were prepared using a
commercial rosemary extract and prepared PM: (i)
control, no additive; (ii) rosemary extract, 0.1%; (iii)
PM, 0.1%. PM was dissolved in ethanol (150 mg mL)1)
before addition. The same amounts of ethanol were added
to all treatments to minimise solvent effect. Each additive
was added to ground chicken meat and mixed for 2 min in
a bowl mixer (model KSM 90; KitchenAid Inc., St Joseph,
MI, USA). The mixed meats were ground again through a
3-mm plate to ensure even distribution of the additives.
Chicken breast meat patties (approximately 40 g each)
were prepared and individually vacuum-packaged in
oxygen-impermeable vacuum bags (9.3 mL O2 m)2 for
24 h at 0 C; Koch, Kansas City, MO, USA). The meat
samples were precooked in a water-bath (90 C) to an
internal temperature of 80 C. After cooking, chicken
patties were chilled in running cold water for 10 min and
the vacuum bags were removed and repackaged individually in oxygen-permeable polythene bags 4 · 6, 2 mil,
(Associated Bag Co., Milwaukee, WI, USA). The aerobically packaged samples were stored at 4 C. Lipid
oxidation, colour and volatiles compounds of the samples
were determined at 0, 1, and 3 days of storage.
2-Thiobarbituric acid-reactive substances values
Lipid oxidation was determined by measuring 2-thiobarbituric acid-reactive substances (TBARS) content
(Ahn et al., 1998). Minced sample (5 g) was placed in a
50-mL test tube and homogenised with 15 mL of
deionised distilled water (DDW) using a Brinkman
Polytron (type PT 10/35; Brikman Instrument Inc.,
Westbury, NY, USA) for 15 s at high speed. The meat
homogenate (1 mL) was transferred to a disposable test
tube (13 · 100 mm), and butylated hydroxytoluene
(7.2%, 50 lL) and thiobarbituric acid/trichloroacetic
acid [20 mm TBA and 15% (w/v) trichloroacetic acid
(TCA)] solution (2 mL) were added. The sample was
vortex-mixed and then incubated in a 90 C water-bath
for 15 min to develop red colour. After cooling for
10 min in cold water, the samples were mixed and
centrifuged at 3000 · g for 15 min at 5 C. The
absorbance of the resulting upper layer was read at
531 nm against a blank prepared with 1 mL of DDW
and 2 mL of TBA/TCA solution. The amounts of
TBARS were expressed as milligram of malonedialdehyde (MDA) per kilogram of meat.
Colour measurement
International Committee on Illumination (CIE) colour
values were measured on the surface of samples using a
LabScan colorimeter (Hunter Associated Laboratories,
Inc., Reston, VA, USA) that had been calibrated against
black and white reference tiles covered with the same
packaging materials as used for the samples. The CIE
L* (lightness), a* (redness) and b* (yellowness) values
were obtained using an illuminant A (light source). Area
view and port size were 0.63 and 1.02 cm, respectively.
The values from four random locations of upper and
bottom surfaces were obtained, averaged and used for
statistical analysis.
Analysis of volatiles compounds
A dynamic headspace analysis was performed using a
Solatek 72 multimatrix vial autosampler and a purge
and trap concentrator 3100 (Tekmar-Dohrmann,
Cincinnati, OH, USA) connected to a gas chromatograph-mass spectrometer (GC-MS; Hewlett-Packard
Co., Wilmington, DE, USA) according to the method
of Ahn et al. (2001). Minced sample (1 g) was placed in
a 40-mL sample vial, the vial was flushed with helium
gas (40 psi) for 3 s, and capped airtight with a Teflon
fluorocarbon resin/silicone septum (I-Chem Co., New
Castle, DE, USA). The maximum waiting of a sample in
a refrigerated (4 C) loading tray was 2 h or less to
minimise oxidative changes during the waiting period
before the start of the analysis. The meat sample was
purged with helium gas (40 mL min)1) for 14 min at
40 C. Volatiles were trapped using a Tenax/charcoal/
silica column (Tekmar-Dohrmann) and desorbed for
2 min at 225 C, focused in a cryofocusing module
()80 C) and then thermally desorbed into a column for
60 s at 225 C.
International Journal of Food Science and Technology 2006, 41 (Supplement 1), 15–19
2006 Institute of Food Science and Technology Trust Fund
Antioxidant activity of Prunus mume for cooked chicken meat S-C. Jo et al.
An HP-624 column (7.5 m, 0.25 mm i.d., 1.4 lm
nominal), an HP-1 column (60 m, 0.25 mm i.d., 0.25 lm
nominal; Hewlett-Packard Co., Wilmington, DE, USA),
and an HP-Wax column (7.5 m, 0.25 mm i.d., 0.25 lm
nominal) were connected using zero dead-volume connectors (J&W Scientific, Folsom, CA, USA). Ramped
oven temperature was used to improve volatile separation. The initial oven temperature of 0 C was held for
1.5 min. After that, the oven temperature was increased
to 15 C at 2.5 C min)1, increased to 45 C at
5 C min)1, increased to 110 C at 20 C min)1, and
then increased to 170 C at 10 C min)1 and held for
2.25 min at that temperature. A constant column
pressure at 21.5 psi was maintained. The ionisation
potential of the mass selective detector (model 5973;
Hewlett-Packard Co.) was 70 eV, and the scan range
was mass ⁄ ion charge (m/z) 19.1–350. Identification of
volatiles was achieved by comparing mass spectral data
of samples with those of the Wiley library (HewlettPackard Co.). Standards, when available, were used to
confirm the identification by the mass selective detector.
The area of each peak was integrated using ChemStation software (Hewlett-Packard Co.) and the total peak
area (total ion counts · 104) was reported as an indicator of volatiles generated from the meat samples.
Table 1 TBARS values of cooked chicken breast meat with the
addition of rosemary extract, raw Prunus mume extract (PM) during
refrigerated storage (mg of MDA kg)1 of meat)
Treatment
Storage (day)
Control
Rosemary
PM
SEM
0
1
3
SEM
0.095az
0.530ay
0.934ax
0.065
0.055cz
0.098cy
0.151cx
0.006
0.078bz
0.382by
0.516bx
0.006
0.003
0.010
0.057
Different letter (a–d) within a row are significantly different (P < 0.05),
n ¼ 4. Different letter within a column (x–z) with the same meat are
significantly different (P < 0.05).
(Hasegawa, 1959) and rutin has been identified as one of
antioxidant components of the fruit of P. mume (Han
et al., 2001). The antioxidant activity of P. mume might be
derived from combination of lots of compounds.
Colour change by P. mume extract
The PM treatment did not significantly change a*b*L*
values (Table 2). This should be a desirable aspect of
added PM in terms of the colour of chicken breast meat,
because consumers usually expect the colour of cooked
poultry breast meat to be not changed.
Statistical analysis
Analysis of variance was conducted according to the
procedure of the General Linear Model using SAS
software 1995 (SAS Institute, 1995). Student-NewmanKeuls’ multiple-range tests were used to compare the
significant differences among the mean values of treatments (P < 0.05). Mean values and standard error of
the means (SEM) were reported.
Inhibition of warmed over flavour
The production of warmed over flavour is the most critical problem and the role of antioxidants is important
Table 2 Colour values of cooked chicken breast meat with the addition
of rosemary extract, raw Prunus mume extract (PM) during refrigerated storage
Breast of chicken
Results and discussion
Storage (day)
TBARS values in cooked chicken breast meat
The methanol extract of PM showed antioxidant activity in cooked chicken breast meat (Table 1). As storage
increased, the overall lipid oxidation was drastically
accelerated as meat structure was destroyed by cooking
and aerobic storage conditions. At 3 days of storage,
PM had lower TBARS values than the control by about
45%. Rosemary extracts showed greatest antioxidant
activity in cooked chicken breast. It agrees to the
previous results of rosemary extracts showing antioxidant activity in foods because of their high contents of
phenolic compounds (e.g. Güntensperger et al., 1998;
Del Campo et al., 2000).
The 80% methanolic extract and ethanolic extract from
fruits of P. mume showed antioxidative and free radical
scavenging activity (Kim et al., 1997; Shim et al., 2002).
P. mume contains several flavonoids such as naringenin
2006 Institute of Food Science and Technology Trust Fund
L value
0
1
3
SEM
a value
0
1
3
SEM
b value
0
1
3
SEM
Control
Rosemary
PM
SEM
84.14y
84.50axy
85.28ax
0.41
83.14xy
82.73by
84.59abx
0.53
84.42
83.88ab
83.70b
0.53
0.50
0.58
0.47
6.12
6.24
6.24
0.10
20.19bx
18.98z
19.80by
0.19
5.97y
6.30x
6.41x
0.13
20.69abx
19.13y
20.82ax
0.29
6.13
6.14
6.34
0.16
20.90ax
19.08y
20.55abx
0.26
0.14
0.16
0.13
0.23
0.30
0.31
Different letter (a–b) within a row are significantly different (P < 0.05),
n ¼ 4. Different letter (x–z) within a column with the same colour value
are significantly different (P < 0.05).
International Journal of Food Science and Technology 2006, 41 (Supplement 1), 15–19
17
18
Antioxidant activity of Prunus mume for cooked chicken meat S-C. Jo et al.
Table 3 Volatiles profile of cooked chicken breast meat with addition
of rosemary extract, raw Prunus mume extract (PM) at 0 day
Table 5 Volatiles profile of cooked chicken breast meat with addition
of rosemary extract, raw Prunus mume extract (PM) at 3 day
Total ion counts · 104
Total ion counts · 104
Chicken breast meat
Compounds
Hydrocarbons
Heptane
Hexane
Octane
Pentane
Toluene
Carbonyls
2-Propanone
Butanal
Heptanal
Hexanal
Pentanal
Propanal
Others
Decane
Disulfide, dimethyl
Total
Control
258a
86
153ab
816a
0b
Rosemary
Chicken breast meat
PM
SEM
45b
110
216a
323b
272a
243a
118
80b
436b
0b
53
8
57
11
5
7554b
0
72a
10423a
822a
1345a
7279b
0
0b
650c
37c
0c
8703a
0
0b
6262b
450b
719b
17
30
14
859
78
117
93b
273b
21852a
0c
822a
9781c
167a
290b
17466b
26
129
1236
Different letter (a–d) within a row are significantly different (P < 0.05),
n ¼ 4.
Table 4 Volatiles profile of cooked chicken breast meat with addition
of rosemary extract, raw Prunus mume extract (PM) at 1 day
Total ion counts · 104
Chicken breast meat
Compounds
Hydrocarbons
Heptane
Hexane
Octane
Oxirane
Pentane
Toluene
Carbonyls
2-Propanone
Butanal
Heptanal
Hexanal
Pentanal
Propanal
Others
Disulfide, dimethyl
Total
Control
Rosemary
PM
SEM
474a
77a
233
106a
1835a
79b
69c
0b
143
0c
311c
271a
266b
88a
228
36b
1178b
23b
50
14
49
11
123
43
6727
0b
288a
28371a
2424a
5106a
7017
0b
90b
6701c
456c
545c
7460
93a
207a
23055b
1770b
3717b
193
49
35
1325
209
307
132
481
177
360
171
572
45
109
Different letter (a–c) within a row are significantly different (P < 0.05),
n ¼ 4.
in storing cooked meat. PM reduced effectively the
off-odour volatiles in cooked chicken breast meat but
produced newly a few volatiles that are supposed to be
Compounds
Hydrocarbons
Heptane
Hexane
Octane
Oxirane
Pentane
Toluene
Carbonyls
2-Heptanone
2-Propanone
Butanal
Heptanal
Hexanal
Pentanal
Propanal
Others
Disulfide, dimethyl
Total
Control
Rosemary
PM
4476bc
185b
415b
409b
1978b
79b
SEM
1103a
303a
782a
689a
3753a
0c
88c
99b
175c
0c
366c
234a
131
25
71
62
361
18
143a
5413b
480
809a
67623a
8710a
11688a
0b
5827b
156
199b
19500c
1473c
1527c
96a
6960a
424
602a
50370b
5178b
8572b
28
298
114
88
3469
790
815
733
102226a
708
30348c
758
76537b
165
5755
Different letter (a–b) within a row are significantly different (P < 0.05),
n ¼ 4.
responsible for the unique PM odour. Considerable
amount of total volatiles were reduced by the addition
of PM or rosemary extracts (Table 3). When volatile
compounds related with lipid oxidation were compared,
volatile aldehydes (propanal, pentanal, hexanal and
heptanal) and a few hydrocarbons (pentane, octane and
nonane) were significantly decreased by the addition of
PM. Hexanal was the most predominant volatile compound in the control meat consisting of almost more
than 50% of the total volatiles and it was reduced into
40% of the control by the addition of PM on the
beginning of storage. In general, hexanal was the most
correlated compound with the TBARS values (e.g. Ahn
et al., 2000; Du et al., 2001) in cooked meats and it can
be a good indicator for lipid oxidation.
At day 1, the hexanal contents of the control chicken
meat increased by about 2.7 times compared with the
0 day (Table 4). The amounts of most volatile aldehydes
in rosemary extract-treated samples were statistically
lower than the PM. At day 3, antioxidant effects were
mainly found in the rosemary extract and PM treatments (Table 5). These results express that the antioxidant effects of rosemary extract and PM could be
maintained for 3 day of storage.
Rosemary extract showed higher antioxidant activity
than P. mume extract in this experiment. Prunus mume,
however, is widely cultured in Asia while rosemary is not.
In addition to the antioxidant activity, P. mume was also
International Journal of Food Science and Technology 2006, 41 (Supplement 1), 15–19
2006 Institute of Food Science and Technology Trust Fund
Antioxidant activity of Prunus mume for cooked chicken meat S-C. Jo et al.
reported to have numerous health benefits (Utsunomiya
et al., 2002). This study provides the antioxidant activities of P. mume when it was added to meat.
Conclusions
In conclusion, the lipid oxidation products in precooked
chicken breast meat showed the antioxidant activities of
P. mume. If more efficient ways are developed to
increase the antioxidant activities by concentrating more
antioxidant components and/or excluding the unnecessary portions, P. mume will become an excellent natural
antioxidant source.
Acknowledgments
This study was supported by Technology Development
Program for Agriculture and Forestry, Ministry of
Agriculture and Forestry, Korea and State of Iowa
Funds. S-C Jo received scholarship from Brain Korea 21
Program.
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