The Extracts of Thermal Processed
Ginger (Zingiber officinale Rosc.)
Rhizome Combined with Honey as
Natural Antioxidant
to Produce Functional Drink
Hari Purnomo1, Firman Jaya2* and Simon Bambang Widjanarko3
1
Dept.Animal Food Technology, Faculty of Animal Husbandry, Brawijaya
University, Malang, East Java,Indonesia.
2 Alumni Post Graduate Program,Faculty of Agricultural Technology, Brawijaya
University, Malang, East Java, Indonesia.
3 Dept Food Technology, Faculty of Agricultural Technology, Brawijaya
University,
Malang, East Java, Indonesia.
ABSTRACT
The thermal processing of 6 minutes and boiling at 100oC gave the best
effect of its antioxidant activity of ginger (Zingiber officinale Rosc.)
rhizome extracts. Whilst the best functional drink was obtained from the
combination of 15 mL honey in 25 mL of ginger water extracts. It had the
following properties: free radical scavenger activity of 35.51±0.02%;
phenolic total of 1.31±0.018 mg/g; and gingerol content of 0.74±0.010
mg/g; taste score of 4.95; colour score of 7.65; and aroma score of 7.4 by
the hedonic scale scoring of 1-9. The analysis with GC-MS identified 1hexadecene (47.81%); hexadecanoic acid (14.25%); and 9-octadecenoic
(15.33%) compounds as antioxidant agents. The FTIR analysis showed
that CH2 kel. bid. def. vibration at 816.80 cm-1 wave was found for the
hexadecene compound, and OH stretch H-bonded at 2944.13 cm-1 wave
were found for the hexadecanoic acid and 9-otadecenoic compounds. It
was proven that the functional drink produced by the combination of 15
mL honey in 25 mL of ginger water extracts had been organoleptically
accepted by the panelists.
Keywords: ginger rhizome, antioxidant, thermal processing, honey
concentration
* Corresponding author address: lone_manutd@yahoo.com
INTRODUCTION
Ginger (Zingiber officinale) rhizome has become a very popular spice
and used widely in Indonesian cuisine as well as in other countries. It is a
common food additive in a number of foods and beverages and it is valued due
to the volatile components especially the aromatic compounds which give a
spicy, pungent and pleasant smell. Bartley and Jacobs (2000) noted that these
aroma compounds only partially contribute to the flavor of fresh ginger rhizome
and the oleoresin content plays an important role for its pungency.
However, there is very little information on the effect of thermal
processing on the antioxidant quality of Indonesian local elephant ginger
rhizome extract. Jaya (2008) reported that in Indonesian traditional beverages
the ginger rhizome was boiled at temperature of around 100ºC for about 20–30
minutes and it is aimed to get a better ginger taste and less bitter taste. He also
reported the effect of type and time of themal processing in ginger (Zingiber
officinale Rosc.) rhizome antioxidant quality and found that 6 minutes of boiling
at 100oC gave the best effect of its antioxidant activity where methyl ester
(0.17%), 9-octadecenoic (0.32%), nortrachelogenin (0.30%) were the
compounds of antioxidant agents, while zingerone compound total peak area
was increased from 5.68% to 6.32%.
Currently, ginger is a common interest of society with high potentially
developed as health drink. Combining honey as other antioxidant is one of the
ways to maintain ginger drink product in consequence of thermal processing.
Antony, Rieck and Dawson (2000) reported the addition of up to 15% honey
inhibited the development of oxidative compounds in cooked turkey meat, with
little further inhibition observed compared to 20% honey. While the study of
Brown, Henderson and Hunt (2006) reported that pinocembrin has been
credited with affording the high radical scavenging abilities of such substances
as Thai ginger and honey/ propolis. The flavonoids in these products, as well as
in a number of pine trees, prove to be antimicrobial as well as effective in vitro
antioxidants. It is used as one of the anti-HIV cocktail of drugs.
Honey is known to be rich in both enzymatic and non-enzymatic
antioxidants, including glucose oxidase, catalase, ascorbic acid, flavonoids,
phenolic acids, carotenoid derivatives, organic acids, maillard reaction products,
amino acids and proteins. It was reported that the composition and antioxidant
capacity of honey depend on the floral source used to collect nectar, seasonal
and environmental factors, as well as processing which also possibly have an
effect on honey composition and antioxidant activity. Honey colour depends on
the potential alkalinity and ash content, as well as on the antioxidatively active
pigments, such as carotenoids and flavonoids (Baltrušaityte, Venskutonis dan
Čeksterytė, 2005). It is also noted that colour accounted for over 60% of the
variance in antioxidant capacity for the honeys examined (r2 = 0.634), with
darker colour having greater antioxidant capacity (D’Arcy, 2005).
Ginger and honey are antioxidant resources that synergistically able to
be combined each other. Weiner (1994) reported that some plants or specific
combinations of herbs in formulations may act as antioxidants by exerting
superoxide scavenging activity or by increasing superoxide dismutase (SOD)
activity in various tissue sites. Each of these groups of compounds are
2
substances that may exert that cell-protective action by more than one
biochemical mechanism.
However, there is limited information available on the combination of
ginger rhizome extracts and honey based on antioxidant activity in Indonesia.
The objectives of current study were to find out the potential of honey as natural
antioxidant if combined with extracts of thermal processed ginger rhizome to
produce functional drink.
1. MATERIALS AND METHODS
1.1 Sample preparation
The thermal processing of 6 minutes and boiling at 100oC was carried
out as described by Jaya (2008). Honey as one of the ingredients were
obtained from one nectar source, such as kapok tree which is taken in second
harvest approximately on May-June. Honey samples were stored at room
temperature for several weeks to produce a darker colour, with expectation of a
high antioxidant properties will be achieved. The amount of honey used were
15, 30 and 45 mL based on the report of FAO (1996) where 236.58 mL potable
water were needed for 47.316 mL honey.
1.2 Determination of antioxidant activity
The mixture of ginger water extract and honey were analyzed for its
antioxidant activity using DPPH (1,1 diphenyl-2-picrylhydrazyl) radical
scavenging assay as described by Khalaf et al. (2007), total phenol assessed
by the method of Miliauskas (2000) and the gingerol content following the
method as desribed by Puengphian and Sirichote(2007).
1.3 GC-MS and FTIR
The antioxidant compounds were analyzed using GC-MS (QP2010SShimadzu) under the following condition : column used were Rtx-5MS,30 m
length and inner diameter of 0.25mm and the initial column temperature was
70oC and final temperature was 280oC (5oC/minute), while the injector
temperature was 300oC with split mode injector and split ratio of 72.6 and
pressure of 14.0 kPa. The flow rate was 40 mL/minute and the flow within the
column was 0.50 mL/minute. The detector temperature was 300oC and using
Helium as the gas carrier with EI (Electron Impact); and the samples volume
injected was 1µl. Compounds were identified by comparing retention
indices/comparing mass spectra of each compound with those of authentic
samples and library. While for functional unit determination the Shimadzu
Fourier Transform Infrared Spectrophotometer - FTIR-8400S were used.
The IR spectra were recorded on FTIR-8400S (Shimadzu Deutchland
GmbH) spectrophotometer in KBr and polyethylene pellets. Samples were
weigh-in at 0.01 g and homogenized with 0.01 g KBr anhydrous by mortar
agate. The mixture of sample and KBr were pressed by vacuum hydrolic
(Graseby Specac) at 1.2 psi to obtain transparancy pellet. Scanned sample
3
passed through infrared, where its continuing wave by detector that connected
to computer and gave a description of tested sample spectrum. Samples were
usually scanned in the absorption area of 600-4000 cm-1. The results of
analysis were consisted of chemical structure, molecular binding form and
certain functional group of tested sample as basic of spectrum type.
1.4 Statistical analysis
All statistical analyses were carried out using Microsoft Excel 2003.
Analysis of variance (ANOVA) followed by Duncan Multiple Range Test at a
level of P<0.01 if there was significant differences between samples. The best
treatment was determined by effectivity index method as described by Susrini
(2005). Organoleptic test analyzed following non-parametric statistical method
by Friedman test (Steel and Torrie, 1989). Identification and in order to
elucidate its structure of antioxidant compounds in functional drink was
accomplished by using gas chromatography-mass spectrometry (GC-MS) and
fourier transform infrared spectrophotometer (FTIR), respectively, with
computerized integrated data processing and descriptively disscussed based on
literature.
2. RESULTS AND DISCUSSIONS
3.1 Determination of ginger water extracts volume
Ginger water extracts volume of ginger rhizome boiled for 6 minutes at
determined by organoleptical procedure including taste, colour and
aroma using hedonic grade test by 30 panelists.
The results showed that the avarage of panelist acceptance to ginger
water extracts taste were ranging from 3.2-5.6 (Figure 1). The amount of ginger
extract of more than 25 mL had a more pungent sense whilst if less it lost the
ginger taste, therefore the panelists prefered as 25 mL sample.
Zingerone were non-volatile compound that contribute to give the
pungent sense of ginger. Jaya (2008) reported that analysis of total zingerone
compound area of ginger rhizome boiled for 6 minutes at 100oC using GC-MS
increased from 5.68% to 6.32%. Friedi (2000) suggested that pungent sense of
ginger corresponding with non-volatile compound was the alcohol group of
oleoresin.
100oC
4
6
5.6
4.9
5
4.4
4
Score
4
3.2
3.4
3.6
10
15
3.9
3.8
35
40
3
2
1
0
5
20
25
30
45
Volume (mL)
Figure 1. Average score of ginger water extracts taste
The score of colour in the organoleptic test showed that the average of
panelists acceptance were ranging from 3.9-5.7 (Figure 2),and the best
combination treatment was 15 mL volume.
Volatile compound contribute to the colour of ginger, extract boiled at
o
100 C as described by Jaya(2008) was edulan II compound. This compound
was reported as a compound which gave a red colour on tomato, and its form
was dark brown concentrated liquid with characteristic odour and taste and
contained 15-30% ginger oil (Anonymous, 1999; Hayati, 2005).
The score of aroma showed that the average of panelists acceptance
were ranging from 3.3-5.8 (Figure 3) and the best combination treatment was
25 mL volume of ginger water extracts.
Volatile component of ginger rhizome was atsiri oil, which is the
compound that gave a typical smell. The main compound that responsible to the
aroma was sesquiterpene hydrocarbon volatile oil (Hayati, 2005). Jaya (2008)
reported that ginger rhizome boiled for 6 minutes using GC-MS produced
geranyl acetate and 3,6-dimethyl-2,3,3a,4,7a-hexahydrobenzofuran, which are
volatile components contribute to herbal plants aroma.
5.7
6
5.1
Score
5
4.2
4.2
5
10
5
4.5
4.7
35
40
4.2
3.9
4
3
2
1
0
15
20
25
30
45
Volume (mL)
Figure 2. Average score of ginger water extracts colour
5
7
5.8
6
Score
5
5
4.1
4.2
4
4.3
4.1
4.3
35
40
45
3.8
3.3
3
2
1
0
5
10
15
20
25
30
Volume (mL)
Figure 3. Average score of ginger water extracts aroma
The best treatment of combination between ginger rhizome boiled for 6
minutes and solvent (potable water), using effectivity index method as
described by Susrini (2005) was 25 mL volume, where the taste score was 5.6;
colour score 5.1; and aroma score 5.8 by the hedonic scale scoring of 1-9.
3.2 Chemical characteristic of honey as raw material
The determination results of honey which will be used for functional drink
for its moisture content, HMF value and diastase activity were showed on Table
1.
Table 1. Average of moisture content (%), HMF value (mg/kg) and diastase
enzym activity (DN) of honey
Parameters
Moisture (%)
HMF (mg/kg)
Diastase enzym activity (DN)
Amount
18.73 ± 0.12
30.28 ± 1.11
12.51 ± 1.41
HMF and diastase enzym activity of this honey were 30.28±1.11 mg/kg
and 12.51±1.41 DN, respectively. While Bogdanov et al. (2004) reported that
before testing these parameters, it should be checked that the HMF content is
below 15 mg/kg. Meanwhile, the Indonesian National Standard (2004) noted
that HMF value generated was lower than 50 mg/kg. Whereas, Jaya (2008)
reported that diastase enzym acivity of several honey in Indonesia was 15.52
DN. Furthermore,Bogdanov et al. (2004) reported that enzym activity of honey
decreases after storage.
The moisture content of honey used in this research was 18.73 ± 0.12 %,
and Bogdanov et al. (2004) noted that the moisture content is a quality
parameter, which affected the physical properties of honey (viscosity,
crystallisation) and also influenced the value of the glucose/water ratio. While
the Indonesian National Standard (2004) noted that the moisture content should
be of 22%. Therefore, the honey sample could be used for functional drink
combined with ginger water extracts and potable water.
6
3.3 Organoleptic evaluation of functional drink
The result of organoleptic evaluation on taste score combining 25 mL
water ginger extract and concentration of honey at various volume (15, 30 and
45 mL) using hedonic scale scoring test by 25 panelists were ranging from 4.957.55 (Figure 4). The best concentration of honey was 30 mL, as most of the
panelists could accept the pungent of ginger and sweetness of honey. Jaya
(2008) reported that the non-volatile compound produced by ginger rhizome
boiled for 6 minutes was zingerone, which gave the effect of pungent, and the
total compound areas of ginger rhizome boiled for 6 minutes using GC-MS
increased from 5.68% (fresh ginger rhizome) to 6.32%.
Sweet sensation of functional drink was due to fructose content in honey.
National Honey Board (2005) reported that in most honey, fructose
predominates and tends to make honey taste slightly sweeter than sugar. On
the average, honey is 1 to 1.5 times sweeter (on a dry weight basis) than sugar.
HMF is a compound that results from the breakdown of simple sugars (such as
glucose or fructose) at pH 5 or lower. HMF occurs naturally in honey, especially
in warm climates.
7.55
8
7
Score
6
5.05
4.95
5
4
3
2
1
0
15
30
45
Honey concentration (mL)
Figure 4. Average of taste score of ginger-honey functional drink
The colour showed that the average of panelists preference were in the
range of 4.8-7.65 (Figure 5). The best concentration of honey was 15 mL,
where most panelists preferred yellowish honey colour. The GC-MS analysis of
the ginger rhizome water extracts sample showed that it contained edulan II
compound which classified as carotenoid group and gave a yellowish-red colour
on tomato and carot as reported by Jaya (2008). Zeb and Mehmood (2004) also
reported that common carotenoids degradation product as Edulan was found in
purple passion fruit, osmanthus, burley tobacco, virginia tobacco which play an
7
important potential role in human health by acting as biological antioxidants,
protecting cells and tissues from the damaging effects of free radicals and
singlet oxygen.
The aroma scores showed that most panelists preference were ranging
from 5.05-7.4 (Figure 6). The best concentration of honey was 15 mL, where
most panelist accepted the beverage with a slightly pungent aroma. These
pungency ginger originated from volatile compounds of ginger rhizome as
sesquiterpene hydrocarbon group, such as: α-pinene, camphene, βphellandrene, ar-curcumene and zingiberene. These evidence were
corresponding with the production of other aroma compounds, such as geranyl
actetate and ethylgluaiacol from ginger rhizome boiled for 6 minutes using GCMS as described by Jaya (2008). Bartley and Jacobs (2000) noted that it is also
possible that the heat involved in the drying process is sufficient to promote
esterification of these terpene alcohols with natural acetic acid (or acetic acid
produced by the thermal decomposition during drying). It is significant that
citronellyl and geranyl acetates have been implicated by previous workers in
imparting important characteristics of ginger flavor.
9
8
7.65
7
Score
6
4.8
5
5.1
4
3
2
1
0
15
30
45
Honey concentration (mL)
Figure 5. Average of colour score of ginger-honey functional drink
The carbohydrates found in honey have the ability to improve the
intensity of desirable flavors and reduce the intensity of others, which transform
starch to other carbohydrates (dextrins, oligo-, di- and monosaccharides) by
diastase enzyme (National Honey Board, 2005). The results of diastase enzyme
activity in this study were 12.51±1.41 DN larger than noted by the Indonesian
National Standard (2004) of 3 DN. These results indicated that starch was
transformed as carbohydrate in honey and have the ability to improve the
intensity of desirable flavors. However, honey aroma was less promenently than
ginger aroma, which is noted by Cuevas-Glory, Pino, Santiago and Sauri-Duch
(2007), who reported that aroma compounds were present in honey at very low
concentrations as complex mixtures of volatile components of different
functionality and relatively low molecular weight.
8
The best treatment according to organoleptic test results were the
combination of 25 mL water ginger extract and 15 mL honey concentration. This
sample had a taste score of 4.95; colour score of 7.65; and aroma score of 7.4
by the hedonic scale scoring of 1-9. Whereas, antioxidant activity as free radical
scavenging activity was 35.51±0.02%, total phenolic content was 1.31±0.018
mg/g and gingerol content was 0.74±0.010 mg/g.
8
7.4
7
Score
6
5.05
5.05
5
4
3
2
1
0
15
30
45
Honey concentration (mL)
Figure 6. Average of aroma scores of ginger-honey functional drink
According to antioxidant activity parameter, the sampel with 15 mL
concentration of honey was smaller than the others (30 and 45 mL
concentration of honey). However, the selected honey concentration with its low
antioxidant activity had been preferred from its sensory properties. It is because
honey can be used as sweetener in beverage if used in advisable amount.
Terna and Ayo (2002) reported that Kunun Zaki of traditional drink in Nigeria, as
the functional food had an acceptable sensory characteristics such as
appearance, colour, texture and taste by consumer and gave less contradiction
and side effects to other nutrient metabolism if used in advisable amount.
3.4 Determination of antioxidant activity on functional drink
Data in Table 2 showed that the average of free radical scavenging
activity using DPPH assay of ginger boiled for 6 minutes (25 mL) combined with
honey at various volume (15, 30, 45 mL) were ranging from 35.51 to 42.73%.
The percentage of functional drink free radical scavenging activity was smaller
than ginger rhizome with/without thermal processing (> 60%) as reported by
Jaya (2008). It is possibly due to the combination of ginger water extracts,
honey and potable water. Ramadan (2008) noted that the antioxidative
properties are correlated not only with the total amount of antioxidants, but also
with the presence of selected compounds. The significantly stronger antiradical
action of some beverages may be due to the differences in content and
composition of bioactives, the differences in kinetic behaviors of potential
antioxidants, a synergism of bioactives with other components present in each
beverage and the diversity in structural characteristics of potential phenolic
antioxidants present.
9
In regards of the average of total phenolic in this study it was found that
the combination of 25 mL water ginger extract and honey concentration were
ranging from 1.30 -2.07 mg/g (Table 2). Schramm and Keen (2005) reported
that consuming 150 grams of corn syrup or buckwheat honey could increase
the availability of phenolic content. This investigation support the conclusion
that phenolic antioxidants from honey are bioavailable and convey antioxidant
protection to healthy human subjects.
While, the average of gingerol content was ranging from 0.74-0.96 mg/g
(Table 2). The addition of potable water as total solution to dissolve combination
of ginger water extract and honey could decrease the gingerol content. Shibuya,
Moriwaki and Tsuji (2008) suggested that a water-soluble ginger root extract
substantially is low gingerol by subjecting a water extract or a hydrous alcohol
extract of a ginger root to isolation and purification such as adsorption
treatment.
Table 2. Average of free radical scavenging activity (%), total phenolic (mg/g)
and gingerol content (mg/g) combined between ginger water extract (25mL) and
concentration of honey at various volume
Concentration Average of free radical
Average of total
Average of gingerol
of honey
scavenging activity
phenolic
content
(mL)
(%)
(mg/g)
(mg/g)
15
35.51 ± 0.02 a
1.31 ± 0.018 a
0.74 ± 0.010 a
30
37.65 ± 0.03 b
1.71 ± 0.013 b
0.84 ± 0.017 b
45
42.73 ± 0.03 c
2.07 ± 0.018 c
0.96 ± 0.018 c
Means  standard deviation in the same column with different letters are significantly
different (P  0.01)
3.5 Identification antioxidant compounds of ginger-honey functional drink
A typical gas chromatogram of ginger-honey functional drink is shown in
Figure 7 and a list of the compounds identified appears in Table 3. According to
%RA, three compounds were found that dominate ginger-honey functional
drink, namely as 1-hexadecene, 9-octadecenoic and hexadecanoic acid.
Murphy, Taylor and McCormick (2004) reported that 1-hexadecene has
an aromatic rings and is highly resistant to oxidation. Whereas Woollett,
Daumerie and Dietschy (1994) suggested that 9-octadecenoic is unsaturated
fatty acid groups commonly used which corresponding with drugs, and also
biologically neutral and does not regulate the low density lipoprotein (LDL)
receptor as the cis isomer does in the hamster. Guillou, Rioux, Catheline,
Thibault, Bouriel, Jan, D’Andrea and Legrand (2003) noted that hexadecanoic
acid contribute as antioxidant compound and vitamin A where added in low fatty
milk to subtitute vitamin that decreased cause by the milk fat removal.
10
Respond
detector
1-hexadecene
Hexadecenoic Acid
9-Octadecenoic
Zingerone
Zingiberene
Retention time (minute)
Figure 7. GC-MS chromatogram of ginger-honey functional drink
Verzera, Campisi, Zappala and Bonnacorsi (2001) reported that
hexadecanoic acid is one of predominating compounds in orange honey and
chestnut honey which is having peak areas between 20-40% using GC-MS.
Table 3. Main compound in ginger-honey functional drink
5
Molecular
Form
C15H24
8
C11H14O3
13
C19H38
17
22
Peak
Name
Compound group
Amount
(%)
0.67
Zingiberene
Monocyclic sesquiterpene
Zingerone
Hydroxil phenol
5.15
1-Hexadecene
Alkene
47.81
C17H34O2
Hexadecanoic Acid
Carboxylic acid
14.25
C9H36O2
9-Octadecenoic
Carboxylic acid
15.33
The infrared spectrum of ginger-honey functional drink and its functional
group analyzed using Fourier Transform Infrared (FTIR) was shown in Figure 8.
Data in Table 4 showed that wave length range from 615.25 cm-1 to 3339.51
cm-1 were found, and although 13 functional compounds were found but only 11
compounds were identified, as peak no 10 and 11 were not identified (Figure 8).
These unidentified peaks were probably due to the relatively low energy
vibration which could not be identified by the infrared spectrophotometer.
11
80
%T
2360.71
60
2078.16
70
50
816.80
1635.52
10
3339.51
0
-10
4500
4000
Sampel :
3500
615.25
1059.81
1258.47
1146.60
20
1342.36
30
1455.19
1416.62
2944.13
40
3000
2500
2000
1750
1500
1250
1000
750
500
1/cm
Figure 8. Infrared spectrum of ginger-honey funcional drink
The IR spectrum of the compound has been studied in order to elucidate
its structure. Data in Table 4 showed that the presence of substituted alkene
(816.80 cm-1), alcohol secondary (1146.60 cm-1), aldehyde (1342.36 and
1416.62 cm-1) and keton (1635.52 cm-1) were not exist neither in fresh ginger
rhizome or ginger boiled for 6 minutes as reported by Jaya (2008). These
functional compounds, excluding alkene, were implied in oxigenated groups,
which were identified using GC-MS as 9-octadecenoic (15.33%), hexadecanoic
acid (14.25%) and zingerone (5.15%).
1-hexadecene was the predominating compound in ginger-honey
functional drink using GC-MS, which is implied in substituted alkene group at
816.60 cm-1. Ruoff (2006) suggested that the most characteristic differrences
among honey were observed between 800 and 1500 cm -1. While the largest
variation in the spectra of honey types were found in the C-O and C-C
stretching regions of the saccharides between 950 and 1050 cm -1.
Table 4. Functional compounds of ginger-honey funcional drink analyzed using
FTIR.
No. Wave length
(cm-1)
1
615.25
2
816.80
3
105.81
4
1146.60
5
1258.47
6
1342.36
7
1416.62
8
1455.19
9
1635.52
10
2078.16
11
2360.71
12
2944.13
13
3339.51
Vibration type
O-H bend
CH2 kel. bid. def
C-OH stretch
C-OH stretch
C-O-C stretch vinyl ether
H-C=O bend. aliphatic aldehyde
H-C=O bend. aliphatic aldehyde
Ring aromatic stretch (4p)
C=C stretch konj.
OH stretch H-bonded
OH stretch; Phenol
Functional compound
Phenol
Subtituted alkene
Alcohol primer (-CH2OH)
Alcohol secondary (-CHROH)
Ether (R-O-R);
Aldehyde (R-CHO)
Aldehyde (R-CHO)
C=C Aromatic
Keton (R-CO-R)
Carboxylic acid (RCOOH)
OH
12
3. Conclusion
Honey as natural antioxidant is synergistically able to combine with
thermal processed ginger rhizome extracts to produce functional drink. It is
concluded that ginger-honey functional drink can be produced which could
maintain the antioxidant properties under such conditions, moreover, the
products also organoleptically acceptable by the panelists.
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