Agricultural
Communication
Biosci. Biotech. Res. Comm. 9(3): 421-427 (2016)
Effect of sodium benzoate on the shelf life of vacuum
packed Catla sh steaks stored at chilled temperature
Kedar, J. G., Pagarkar, A. U*, Shingare, P. E., Bhosale, B. P., Shinde, K. M. and Kulkarni, G. N.
College of Fisheries, (Dr. B. S. Konkan Agricultural University, Dapoli) Shirgaon, Ratnagiri- 415629,
Maharashtra, India
ABSTRACT
Fish is a rich source of high quality protein, essential vitamins and polyunsaturated fatty acids. The increasing
demand for high quality fresh seafood has intensi ed the search for methods and technologies for better sh utili-
zation. Modi ed atmosphere packaging (MAP) and vacuum packaging (VP), along with refrigeration, have become
increasingly popular preservation techniques,which have brought major changes in storage, distribution, and market-
ing of raw and processed products to meet consumer demands. In the present study, organoleptic, biochemical and
microbiological quality changes were observed in chilled stored vacuum packed catla sh steaks treated with 0.0,
0.5, 1.0, 1.5 and 2.0% sodium benzoate. Organoleptic, biochemical and microbiological analysis showed that chilled
stored vacuum packed catla sh steaks with treatment of sodium benzoate had longer shelf life of 27 days, whereas
untreated vacuum packed catla sh steaks had a shelf life of 18 days. The results of present study revealed that
vacuum packaging alone, without treatment, would not be of much effective under the reported experimental condi-
tions. The ndings of the present study, clearly suggest that a combination of vacuum packaging, sodium benzoate
and storage at chilled temperature could be used to prolong the shelf life of catla.
KEY WORDS: VACUUM PACKAGING, SODIUM BENZOATE, CHILLED STORAGE, SHELF LIFE, CATLA FISH
421
ARTICLE INFORMATION:
*Corresponding Author: pagarkarau@gmail.com
Received 30
th
July, 2016
Accepted after revision 10
th
Sep, 2016
BBRC Print ISSN: 0974-6455
Online ISSN: 2321-4007
Thomson Reuters ISI ESC and Crossref Indexed Journal
NAAS Journal Score 2015: 3.48 Cosmos IF : 4.006
© A Society of Science and Nature Publication, 2016. All rights
reserved.
Online Contents Available at: http//www.bbrc.in/
INTRODUCTION
Fish is a rich source of high quality protein, essential
vitamins and polyunsaturated fatty acids (Mohan et al.,
2009). The increasing demand for high quality fresh sea-
food has intensi ed the search for methods and tech-
nologies for better sh utilization. Modi ed atmosphere
packaging (MAP) and vacuum packaging (VP), along
with refrigeration, have become increasingly popular
preservation techniques, which have brought major
changes in storage, distribution, and marketing of raw
and processed products to meet consumer demands
(Ozogul et al., 2004; Pagarkar et al., 2015 ).
Sodium benzoate (NaC
6
H
5
CO
2
) is a preservative found
naturally in cranberries, prunes, greengage plums, cin-
namon, cloves and apples. The Food and Drug Admin-
422 EFFECT OF SODIUM BENZOATE ON THE SHELF LIFE OF VACUUM PACKED CATLA FISH STEAKS STORED BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS
Kedar et al.
istration (FDA) includes sodium benzoate in its list of
direct food substances af rmed as Generally Recognized
As Safe (GRAS). Sodium benzoate has been generally
reported to be used at concentrations below 0.1% (CFR,
2011). In some countries levels up to 0.2 % and 0.3 %
are permitted and are commonly used (Sara et al., 1994).
Sodium benzoate has antimicrobial properties prevent-
ing the growth of bacteria and mold. It prolongs the
shelf life of sh for a very long period without affect-
ing its texture, taste and appearance (Omojowo, et al.,
2010). Catla (Catla catla) is one of the fastest growing
fresh water sh among the Indian major carps and it is
cultured throughout India on large scale. It is marketed
in fresh or iced conditions in the domestic areas. Prepa-
ration of chilled steaks of catla in ‘ready-to-cook’ form
would enable to market the sh to long distanc.
MATERIAL AND METHODS
Freshly caught catla (Catla catla) sh samples procured
from Tasgaon reservoir at Sangli district in western
Maharashtra (India) were immediately brought to the
laboratory in iced condition by keeping in insulted boxes
lled with crushed ice in the ratio of 1:1 for further pro-
cessing. Steaks of thickness 1.5-2.0 cm were made fol-
lowing the method of Shalima (1997). The steaks were
divided into 5 groups and were dipped in solution of
sodium benzoate of 0.0, 0.5, 1.0, 1.5 and 2.0% concen-
tration respectively, for 5 minute. After proper draining
vacuum packaging was carried out in packaging mate-
rial made up of nylon laminated polyethylene of thick-
ness 100 micron with a capacity of 200 g each and of
size 30.0 × 12.0 cm. Each pack had a weight ranges from
150-200 g.
The vacuum packed samples with or without treat-
ment were coded as untreated vacuum packed steaks (A),
0.5% sodium benzoate treated vacuum packed steaks (B),
1.0% sodium benzoate treated vacuum packed steaks (C),
1.5% sodium benzoate treated vacuum packed steaks
(D) and 2.0% sodium benzoate treated vacuum packed
steaks (E) respectively. Vacuum packed catla sh steaks
were stored in an insulated thermocol box with crushed
ice (1:1). Insulated sh box was kept at room tempera-
ture. Re-icing was done every day after proper drain-
ing of ice melt water to supplement the loss of ice due
to melting. Storage studies were conducted for a period
of 27 days. All the samples were analyzed at intervals
of 3 days for sensory, biochemical and microbiological
characteristics.
Sensory evaluation was carried out by trained pan-
elist using 9 point hedonic scale (ISI, 1975). The scores
given by the panelists for each of the attributes were
pooled and the average scores are presented.
Biochemical changes viz. pH, peroxide value (PV)
and salt soluble nitrogen (SSN) were determined as per
AOAC (2005), also total volatile base nitrogen (TVB-N)
was determined by the procedure given by Beatty and
Gibbons (1937). Total plate count (TPC), Escherichia
coli, Staphylcoccus aureus and Salmonella as per USFDA
(2001). Recorded data were analysed to test signi cant
difference by applying analysis of variances (ANOVA)
tool available in MS-Excel 2007 and Student-Newman-
Keuls (SNK) test. The signi cant differences were tested
by 5% level of signi cances and are mentioned as
p<0.05 for signi cances difference (Zar, 2004).
RESULTS AND DISCUSSION
The catla sh used for study had a total length ranges
from 35 to 45 cm and total weight ranges from 1.2 to
1.5 kg. The initial quality of raw material i.e. fresh catla
sh is given in Table 1. The moisture, crude protein, fat
and ash contents were 79.24, 18.59, 1.23 and 0.94 %
respectively (Table 2). The results for proximate compo-
sition are similar to that reported by Bhosale (2002) and
Pawar et al. (2013) with a little difference. Gopakumar
(2002) reported the moisture, crude protein, fat and ash
contents in catla sh as 76.30, 19.60, 1.30 and 0.90%
respectively. The variation in the chemical composition
of sardines is closely related to nutrition, living area,
sh size, catching season, seasonal and sexual varia-
tions as well as other environmental conditions (Ozogul
et al., 2004).
Catla sh steaks treated with 0.5, 1.0, 1.5 and 2.0
% of sodium benzoate for 5 minutes showed residue of
sodium benzoate 0.0192, 0.0376, 0.0664 and 0.0952%
respectively in meat (Table 3). The residual sodium ben-
Table 1: Quality of fresh catla sh muscle
Quality parameter Catla sh muscle
A. Sensory score for overall
acceptability (9 point hedonic
scale)
9.0 ± 1.07
B. Biochemical quality
pH 5.56 ± 0.01
TVB-N (mg/100g) 7.15 ± 0.01
PV (meq of O2/ kg) 2.37 ± 0.03
SSN (mg % of total nitrogen) 65.42 ± 0.01
C. Microbiological quality
Total plate count (cfu/g) 5.39 x 10
2
Staphylococcus aureus ND
Escherichia coli ND
Salmonella ND
Note: ND = Not Detected
BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS EFFECT OF SODIUM BENZOATE ON THE SHELF LIFE OF VACUUM PACKED CATLA FISH STEAKS STORED 423
Kedar et al.
zoate levels after 5 minute dip treatment did not exceed
the acceptable limit of 0.1 % for all treated steaks.
SENSORY CHANGES
During the chilled storage studies of 27 days, the over-
all acceptability score for all samples showed declining
trend. Sample A showed acceptability score from 9.0 to
4.6 at the end of 18 days, while B, C, D and E showed
acceptability score from 9.0 to 4.0, 9.0 to 4.1, 9.0 to
4.2 and 9.0 to 4.3 respectively at the end of 27 days
(Fig. 1). The result of the present study is supported by
Mohan et al. (2009) for overall acceptability of seer sh
steaks packed with O2 scavenger during chilled storage.
Jeyasekaran et al. (2004) also reported declining trend
for overall acceptability scores of vacuum packed tuna
(Euthynnus af nis) chunks stored at refrigerated tem-
perature. The results of ANOVA test for overall accept-
ability scores revealed that, there was no signi cant dif-
ference (p>0.05) between them.
BIOCHEMICAL CHANGES
Chnages in pH
The pH values for all samples of chilled stored catla sh
steaks showed increasing trend from 5.56 to 6.37 in A,
5.55 to 6.35 in B, 5.55 to 6.32 in C, 5.55 to 6.30 in D
and 5.55 to 6.27 in E at the end of 27 day (Fig. 2). On
the same line, slight increase in pH (from 6.28 to 6.62) of
mackerel (Rastrelliger kanagurta) stored with antimicro-
bials treated ice (prepared by adding mixture of sodium
benzoate, Butylated Hydroxy Anisole; BHA and fumaric
in the ratio 90:9:1 to the water at the concentration of
500 ppm) was reported by Chandra (2006).
Juvekar (2007) also reported rising trend in pH (from
6.38 to 7.08) of vacuum packed black king sh mack-
erel (Rachycentron canadus) esh stored at 5 ± 1
0
C. The
increase in pH may be attributed to the production of
volatile base compounds and alkaline compounds such
as ammonia by spoilage bacteria (Cann et al., 1983). The
results of ANOVA test for pH revealed that, there was no
signi cant difference (p>0.05) between them.
CHANGES IN TOTAL VOLATILE BASE
NITROGEN (TVB-N)
The TVB-N (mg/100g) content for all samples of chilled
stored catla sh steaks showed increasing trend from
7.15 to 36.18 in A,
7.13 to 33.51 in B, 7.13 to 33.35
in C, 7.12 to 33.32 in D and 7.12 to 15.93 in E at the
Table 2: Proximate composition of fresh
catla muscle
Composition (%) Catla sh muscle
Moisture 79.24
Crude protein 18.59
Fat 1.23
Ash 0.94
Table 3: Residue of sodium benzoate in
treated catla sh muscle
Treatment (w/v) Residue after 5 min dip
treatment
0.5 % 0.0192 %
1.0 % 0.0376 %
1.5 % 0.0664 %
2.0 % 0.0952 %
FIGURE 1. Organoleptic score for overall acceptability of chilled stored
vacuum packed catla sh steaks
424 EFFECT OF SODIUM BENZOATE ON THE SHELF LIFE OF VACUUM PACKED CATLA FISH STEAKS STORED BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS
Kedar et al.
end of 27 day (Fig. 3). The TVB-N values of all samples
were within the acceptable limit during chilled storage
period. The similar results for TVB-N content (from 9.80
to 29.40 mg/100 g) were recorded by Juvekar (2007) for
vacuum packed black king sh mackerel (Rachycentron
canadus) esh stored at low temperature. On the same
line, Ozogul et al. (2004) reported increasing trend of
TVB-N (from 5.0 mg/100 g to 19.0 mg/100 g) during
chilled storage of vacuum packed sardines (Sardina pil-
chardus), whereas Karim et al. (2011) reported increase
in TVB-N (from 22.40 to 68.32 mg/100 g ) during ice
storage of herring (Clupea harengus).
The results of ANOVA test for TVB-N revealed that,
there was signi cant difference (p<0.05) between them.
Further results of Student-Newman-Keuls (SNK) test
indicated that,
sample E was signi cantly superior to
other samples (p<0.05). Fraser and Sumar (1998) indi-
cated that bacterial catabolism of amino acids in sh
muscle results in the accumulation of ammonia and
other volatile bases. Therefore, in the present study
it can be concluded that combined effect of vacuum
packaging and sodium benzoate inhibited the growth
of microorganisms, which causes the slight increase in
TVB-N value of sodium benzoate treated vacuum packed
catla sh steaks.
CHANGES IN PEROXIDE VALUE (PV)
The peroxide value (meq of O2/ kg) for all samples of
chilled stored catla sh steaks showed increasing trend
from 2.37 to 9.75 in A, 2.36 to 6.25 in B, 2.36 to 5.25 in
FIGURE 2. Changes in pH of chilled stored vacuum packed catla sh steaks
FIGURE 3. Changes in TVB-N content of chilled stored vacuum packed
catla sh steaks
BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS EFFECT OF SODIUM BENZOATE ON THE SHELF LIFE OF VACUUM PACKED CATLA FISH STEAKS STOREDS 425
Kedar et al.
C, 2.35 to 5.18 in D and 2.35 to 3.12 in E at the end of 27
day (Fig. 4). On the same line, increase in PV (from 4.77
to 17.49 meq of O
2
/ kg) of mackerel (Rastrelliger kana-
gurta) stored with antimicrobials treated ice (prepared by
adding mixture of sodium benzoate, Butylated Hydroxy
Anisole; BHA and fumaric in the ratio 90:9:1 to the
water at the concentration of 500 ppm) was reported by
Chandra (2006). Phadke (2009) reported increasing trend
(from 0.10 to 3.16 meq of O2/ kg) in PV values of ice
stored seer sh (S. guttatus) llets.
The results of ANOVA test for peroxide value revealed
that, there was signi cant difference (p<0.05) between
them. Further results of Student-Newman-Keuls (SNK)
test indicated that, B, C, D
and E
samples were signi -
cantly different from sample A (p<0.05), but signi -
cant difference was not observed between B, C, D
and
E
samples. The PV values of of all samples were within
the acceptable limit during chilled storage. The vacuum
packed samples showed slower rate of increase in PV. It
may be attributed to the vacuum packaging which offers
an excellent protection against oxidative rancidity by
the effective removal of oxygen in the packs (Ray, 2004).
CHANGES IN SALT SOLUBLE NITROGEN (SSN)
Salt soluble nitrogen (mg % of total nitrogen) content
for all samples of chilled stored catla sh steaks showed
decreasing trend from 65.42 to 29.24 in A, 65.44 to
35.94 in B, 65.44 to 36.36 in C, 65.42 to 36.45 in D
and
65.42 to 56.48 in E at the end of 27 day (Fig. 5).
FIGURE 4. Changes in PV of chilled stored vacuum packed catla sh steaks
FIGURE 5. Changes in SSN content of chilled stored vacuum packed catla
sh steaks
Kedar et al.
426 EFFECT OF SODIUM BENZOATE ON THE SHELF LIFE OF VACUUM PACKED CATLA FISH STEAKS STORED BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS
The results of ANOVA test for salt soluble nitrogen
revealed that, there was signi cant difference (p<0.05)
between them. Further results of Student-Newman-
Keuls (SNK) test indicated that,
sample E was signi -
cantly superior to other samples (p<0.05). Dunn and
Rustad (2008) reported declined in salt soluble proteins
in superchilled vacuum packed Atlantic salmon (Salmo
salar) llets during storage period. The decrease in SSN
may be attributed to the protein denaturation in sh
muscle (Dunn and Rustad, 2008).
MICROBIOLOGICAL CHANGES
Total plate count (cfu/g) for all samples of chilled stored
catla sh steaks showed increasing trend from 5.38 x 10
2
to 6.31 x 10
6
in A, 5.37 x 10
2
to 6.03 x 10
6
in B, 5.35 x
10
2
to 1.74 x 10
6
in C, 5.34 x 10
2
to 7.08 x 10
5
in D and
5.32 x 10
2
to 5.62 x 10
3
in E at the end of 27 day (Fig. 6).
Results of the present study are supported by reports on
changes in TPC (from 1.0 x 10
4
to 1.0 x 10
6
) of vacuum
packed sardines (Sardina pilcharus) stored at 4
0
C (Ozo-
gul et al., 2004). Manju et al. (2007) also noted increase
in TPC (from 8.71 x 10
4
to 1.0 x 10
7
) of chilled stored
vacuum packed pearlspot (Etroplus suratensis). Juvekar
(2007) reported increased trend of TPC (from 1.10 x 10
3
to 1.96 x 10
5
) vacuum packed black king sh mackerel
(Rachycentron canadus) esh stored at low temperature.
The results of ANOVA test for total plate count
revealed that, there was signi cant difference (p<0.05)
between them. Further results of Student-Newman-
Keuls (SNK) test indicated that, D
and E
samples were
signi cantly different from other samples (p<0.05), but
signi cant difference was not observed between D
and
E
samples.
In the present study, vacuum packed sample with
2.0% sodium benzoate showed slower rate of increase in
TPC as compared to other samples. It may be attributed
to vacuum packaging which decreases the growth of
aerobic spoilage microorganisms (Ray, 2004) and higher
concentration of sodium benzoate which is having anti-
microbial properties against bacteria, moulds and yeast
(Omojowo et al., 2010).
The S. aureus, E. coli and Salmonella were not
detected during the entire period of chilled storage in
all samples of catla sh steaks. Similar results were
reported by Rathod et al. (2014) in sh cutlet made from
Pangasius sh (Pangasianodon hypophthalmus), during
storage in refrigerated display unit (-15 to -18
0
C).
CONCLUSION
The results of present study revealed that vacuum pack-
aging alone, without treatment, would not be of much
effective under the reported experimental conditions.
The results of the present study, clearly suggest that a
combination of vacuum packaging, sodium benzoate
and storage at chilled temperature could be used to pro-
long the shelf life of catla.
ACKNOWLEDGEMENTS
The authors are thankful to University authorities of Dr.
B. S. Kokan Krishi Vidyapeeth, Dapoli, Associate Dean,
College of Fisheries, Ratnagiri and National Agricultural
Innovative Project (NAIP) project members for their
encouragement and providing necessary facilities for
the present work.
FIGURE 4.14. Changes in TPC values of chilled stored vacuum packed catla
sh steak
Kedar et al.
BIOSCIENCE BIOTECHNOLOGY RESEARCH COMMUNICATIONS EFFECT OF SODIUM BENZOATE ON THE SHELF LIFE OF VACUUM PACKED CATLA FISH STEAKS STORED 427
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