1
2
3
4
TABLE 1: Scale employed for evaluating the freshness degree of blackspot seabream
Attribute
Skin
Eyes
External odour
Gills
Consistency
Flesh odour
5
Highest quality (E)
Good quality (A)
Fair quality (B)
Very intense pigmentation; Milky mucus; insignificant
Slightly greyish mucus;
transparent mucus
pigmentation losses
pigmentation without shine
Convex; transparent
cornea; bright and black
pupil
Sharply seaweedy and
shellfish smell
Brightly red; without
odour; lamina perfectly
separated
Presence or partial
disappearance of rigor
mortis symptoms
Sharply seaweedy and
shellfish smell
Unacceptable (C)
Widely opaque mucus;
important pigmentation
losses
Convex and slightly
sunken; slightly opalescent
Flat; opalescent cornea;
Concave and milky cornea;
cornea; black and cloudy
opaque pupil
internal organs blurred
pupil
Weakly seaweedy and
Incipiently putrid or rancid
Putrid or rancid
shellfish smell
Rose coloured; without
Slightly pale; incipient
Grey-yellowish colour;
odour; lamina adhered in
fishy odour; lamina
intense ammonia odour;
groups
adhered in groups
lamina totally adhered
Firm and elastic; pressure
Presence of mechanical
signs disappear
signs; elasticity notably
Important shape changes
immediately and
reduced
due to mechanical factors
completely
Weakly seaweedy and
Incipiently putrid or rancid
Putrid or rancid
shellfish smell
1
2
3
4
5
TABLE 2: Comparative sensory evaluation of fresh blackspot seabream subjected to slaughter and chilled storage in flow ice (FI)
or ozonised flow ice (OFI), respectively*
Attribute
6
7
8
9
10
11
12
13
3
6
Icing Time (days)
9
FI
OFI
A
A
Skin
FI
E
OFI
E
FI
A
OFI
A
Eyes
E
E
E
E
A
External odour
E
E
A
E
Gills
E
A
A
Consistency
A
A
Flesh Odour
E
E
13
16
FI
B
OFI
B
FI
B
OFI
B
A
A
A
B
A
A
A
B
B
B
B
A
B
A
B
B
B
B
A
A
A
A
B
B
C
B
E
E
A
A
A
A
A
A
* Freshness categories as expressed in Table 1. Analyses carried out on day 1 provided E category for all attributes.
1
TABLE 3: Comparative growth of different microbial groups* in the muscle of blackspot seabream specimens
2
subjected to slaughter and chilled storage in flow ice (FI) and ozonised flow ice (OFI), respectively**
3
4
5
Icing
time
(days)
1
3
6
9
13
16
6
7
8
9
10
11
12
Aerobic
mesophiles
Psychrotrophes
Lipolytic bacteria
Proteolytic
bacteria
FI
OFI
FI
OFI
FI
OFI
FI
OFI
2.75 b
(0.27)
1.88
(0.43)
1.60
(0.86)
1.92 b
(0.33)
4.04 b
(0.19)
3.19 b
(0.18)
2.10 a
(0.14)
1.43
(0.42)
1.73
(0.61)
1.00 a
(0.05)
3.53 a
(0.23)
2.22 a
(0.52)
2.72 b
(0.21)
2.72 b
(1.21)
1.10
(0.14)
3.21 b
(0.21)
3.27
(0.23)
3.29
(0.25)
2.10 a
(0.04)
1.00 a
(0.05)
1.90
(1.27)
2.69 a
(0.14)
3.10
(0.22)
2.79
(0.23)
2.00
(0.05)
2.00
(0.05)
2.00
(0.04)
2.42
(0.32)
2.89
(0.69)
3.49
(0.78)
2.38
(0.35)
2.38
(0.35)
2.00
(0.05)
2.20
(0.28)
2.55
(0.79)
2.60
(0.86)
2.95
(0.95)
2.00
(1.00)
2.33
(0.50)
2.35
(0.35)
3.77
(0.12)
3.73 b
(0.83)
2.68
(0.88)
2.10
(0.18)
2.10
(0.18)
2.00
(0.10)
3.28
(0.90)
2.20 a
(0.14)
Histamineproducing
bacteria
FI
OFI
2.30
(0.40)
2.00
(0.10)
2.00
(0.10)
2.10
(0.14)
2.96
(1.05)
2.66
(0.75)
2.10
(0.14)
2.00
(0.10)
2.00
(0.10)
2.00
(0.10)
2.33
(0.45)
2.00
(0.10)
* Average values of three (n = 3) independent determinations, expressed as log CFU g-1 muscle. Standard deviations are indicated
in brackets.
** For each microbial group, mean values followed by a different letter (a, b) denote significant differences (p<0.05) between both
icing batches.
1
2
3
4
5
TABLE 4: Identification of histamine-producing bacteria isolated from the muscle of blackspot seabream
Strain
number
1
2
3
4
5
6
8
10
11
14
21
22
23
6
7
8
9
10
11
12
13
14
15
Gram
+
+
-
Catalase Oxydase
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
Bacterial species
Stenotrophomonas maltophilia
Pseudomonas sp
Pseudomonas fragi
Pseudomonas putida
Stenotrophomonas sp
Stenotrophomonas maltophilia
Stenotrophomonas maltophilia
Bacillus cereus
Pseudomonas putida
Shewanella baltica
Bacillus cereus
Pseudomonas syringae
Pseudomonas sp
1
TABLE 5: Comparative assessment* of trimethylamine oxide (TMAO), total volatile bases (TVB) and trimethylamine
2
(TMA) in the muscle of blackspot seabream specimens subjected to slaughter and chilled storage in flow ice (FI) and
3
ozonised flow ice (OFI), respectively**
4
5
6
Icing Time
(days)
1
3
6
9
13
16
Trimethylamine oxide-nitrogen
(mg TMAO-N kg-1 muscle)
FI
OFI
187.1
204.0
(18.5)
(40.0)
197.6
210.7
(0.5)
(18.6)
180.0
221.8
(22.1)
(48.7)
186.6
215.0
(1.9)
(33.2)
192.6
208.1
(11.8)
(11.1)
164.0 a
193.9 b
(2.3)
(4.9)
Total volatile base-nitrogen
(mg TVB-N kg-1 muscle)
FI
OFI
280.9
297.6
(6.6)
(15.1)
310.6
314.9
(12.4)
(15.4)
310.6
313.4
(17.5)
(17.2)
305.7
313.8
(8.9)
(16.3)
264.1
284.1
(16.5)
(10.8)
271.2
284.7
(14.7)
(14.7)
Trimethylamine-nitrogen
(mg TMA-N kg-1 muscle)
FI
OFI
0.3
0.3
(0.1)
(0.0)
0.7 b
0.5 a
(0.1)
(0.0)
0.6
0.6
(0.0)
(0.1)
1.4 b
0.7 a
(0.4)
(0.0)
1.5
1.5
(0.0)
(0.1)
2.5
2.4
(0.2)
(0.5)
7
8
9
10
* Average values of three (n = 3) independent determinations. Standard deviations are indicated in brackets.
11
** For each quality index, mean values followed by a different letter (a, b) denote significant differences (p<0.05) between both icing
12
conditions.
1
TABLE 6: Comparative lipid oxidation evolution* in the muscle of blackspot seabream specimens subjected to slaughter
2
and chilled storage in flow ice (FI) and ozonised flow ice (OFI), respectively**
3
4
5
Icing Time
(days)
1
3
6
9
13
16
Peroxide value
(meq oxygen kg-1 lipids)
FI
OFI
2.45
2.54
(0.86)
(0.75)
1.75 a
5.93 b
(0.06)
(1.69)
2.75 a
3.72 b
(0.14)
(0.37)
2.58
2.20
(1.35)
(0.65)
3.94
4.47
(0.44)
(0.99)
6.66 a
8.34 b
(0.16)
(1.10)
Thiobarbituric acid index
(mg malondialdehyde kg-1 muscle)
FI
OFI
0.07 a
0.10 b
(0.01)
(0.01)
0.09
0.08
(0.01)
(0.04)
0.07 a
0.12 b
(0.01)
(0.02)
0.07
0.06
(0.02)
(0.03)
0.05 a
0.08 b
(0.01)
(0.01)
0.21
0.19
(0.09)
(0.08)
Fluorescence formation
FI
2.07
(0.10)
2.13
(0.17)
1.58
(0.70)
2.07
(0.08)
3.18
(0.39)
3.34
(0.13)
OFI
2.18
(0.21)
2.17
(0.06)
1.92
(0.21)
2.36
(0.51)
3.45
(0.18)
3.54
(0.21)
6
7
8
9
10
11
* Average values of three (n = 3) independent determinations. Standard deviations are indicated in brackets.
12
** For each quality index, mean values followed by a different letter (a, b) denote significant differences (p<0.05) between both icing
13
conditions.