Gutted and Un-Gutted Sea Bass (Dicentrarchus Labrax) Stored in Ice: Influence on Fish Quality and Shelf-Life

Figures & data

Table 1 EU fish sensory scheme.

Criteria	Extra Category	A Category	B Category	C Category (Not admitted)
Skin	Bright, iridescent pigment or opalescent; no discoloration	Pigmentation bright but not lustrous	Pigmentation in the process of becoming discolored and dull	Dull pigmentation
Skin mucus	Aqueous, transparent	Slightly cloudy	Milky	Yellowish grey, opaque mucus
Eye	Convex (bulging); black, bright pupil; transparent cornea	Convex and slightly sunken; black dull pupil; slightly opalescent cornea	Flat; opalescent cornea; opaque pupil	Concave in the center; grey pupil; milky cornea
Gills	Bright color; no mucus	Less colored; transparent mucus	Brown/grey becoming discolored; thick, opaque mucus	Yellowish; milky mucus
Peritoneum (in gutted fish)	Smooth; bright; difficult to detach from flesh	Slightly dull; can be detached from flesh	Speckled; comes away easily from flesh	Does not stick
Smell of gills and abdominal cavity	Sea weedy	No smell of seaweed; neutral smell	Fermented; slightly sour	Sour
Flesh	Firm and elastic; smooth surface	Less elastic	Slightly soft (flaccid), less elastic; waxy and dull surface	Soft; scales easily detached from skin, surface rather wrinkled

Table 2 Quality index scheme for sea bass.

Parameters being assessed	0 points	1 points	2 points	3 points
Appearance	Very bright	Bright	Slightly dull	Dull
Slime	Absent	Slightly slimy	Slimy	Very Slimy
Stiffness	Pre-rigor	Rigor	Post-rigor
Eyes clarity	Clear	Slightly cloudy	Cloudy
Eye shape	Normal	Flatsunken	Sunken or swollen
Eyes iris	Visible	Slightly visible	Not visible
Gills color	Dark red	Red	Brown	Dark brown or grey
Gills mucus	Absent	Slight	Moderate	Excessive or sticky
Gills smell	Neutral	Fishy	Stale	Spoilt
Flesh color	White iridescent	Some yellowish	Yellow	Excessive yellow

Table 3 Proximate composition of Sea bass.

Water (%)	Ash (%)	Protein (%)	Fat (%)
70.43 ± 0.25	2.05 ± 0.1	21.26 ± 0.05	5.60 ± 0.03

Table 4 Changes in sensory analyses of whole ungutted (A), gutted (B) sea bass stored in ice.

	Sensory Analyses
	EU score		Quality index		Cooked fish
Storage time	A	B	A	B	A	B
1	0.26 (± 0.03)a	0.20 (± 0.01)a	3.89 (± 0.16)a	3.73 (± 0.25)a	9.54 (± 0.21)a	9.59 (± 0.29)a
3	0.33 (± 0.01)a	0.31 (± 0.04)a	6.66 (± 0.25)a	6.33 (± 0.71)a	8.95 (± 0.73)a	8.72 (± 0.36)a
5	0.81 (± 0.05)a	0.77 (± 0.06)a	10.59 (± 0.88)a	10.55 (± 1.10)a	8.46 (± 0.34)a	8.21 (± 0.22)a
7	1.34 (± 0.04)a	1.40 (± 0.02)a	15.26 (± 1.01)a	15.09 (± 0.61)a	7.58 (± 0.42)a	7.59 (± 0.22)a
9	2.03 (± 0.03)b	1.95 (± 0.09)b	19.96 (± 1.15)b	19.12 (± 1.60)b	6.05 (± 0.32)a	6.01 (± 0.08)a
11	2.74 (± 0.05)a	2.76 (± 0.11)a	23.95 (± 0.97)a	23.63 (± 1.48)a	3.85 (± 0.09)a	3.85 (± 0.12)a
13	2.83 (± 0.08)a	2.80 (± 0.04)a	24.75 (± 1.21)a	24.70 (± 0.77)a	2.90 (± 0.11)b	2.50 (± 0.09)b
	R^2 = 0.9669	R^2 = 0.9657	R^2 = 0.9873	R^2 = 0.9831	R^2 = 0.9488	R^2 = 0.9462
	y = 0.24x − 0.279	y = 0.25x − 0.241	y = 1.89x + 1.475	y = 1.90x + 1.692	y = −0.56x + 10.697	y = −0.55x + 10.728

Table 5 Changes in pH, TVB-N, and TMA-N of whole ungutted (A), gutted (B) sea bass stored in ice.

	Chemical Analyses
	pH		TVB-N (mg/100g)		TMA-N (mg/100g)
Storage time	A	B	A	B	A	B
1	6.46 (± 0.01)a	6.55 (± 0.01)a	17.66 (± 0.11)a	16.10 (± 0.14)a	0.71 (± 0.04)a	0.68 (± 0.01)a
3	6.59 (± 0.01)a	6.49 (± 0.01)a	19.32 (± 0.18)a	20.94 (± 0.22)a	0.87 (± 0.06)a	0.87 (± 0.06)a
5	6.54 (± 0.02)a	6.56 (± 0.01)a	14.76 (± 0.10)a	16.35 (± 0.08)a	0.90 (± 0.04)a	1.23 (± 0.05)a
7	6.63 (± 0.01)a	6.71 (± 0.02)a	18.11 (± 0.21)a	17.58 (± 0.18)a	1.77 (± 0.09)a	1.48 (± 0.10)a
9	6.56 (± 0.01)a	6.51 (± 0.01)a	12.49 (± 0.16)a	10.55 (± 0.10)a	1.81 (± 0.05)a	1.97 (± 0.02)a
11	6.76 (± 0.02)a	6.87 (± 0.01)a	16.55 (± 0.25)a	18.10 (± 0.28)a	1.82 (± 0.03)a	2.00 (± 0.11)a
13	6.64 (± 0.01)a	6.67 (± 0.01)a	14.14 (± 0.09)a	15.74 (± 0.17)a	3.94 (± 0.12)a	3.38 (± 0.09)a

Table 6 Correlation coefficients between sensory score, volatile amine, and microbial counts in whole and gutted sea bass.

	Psychrotrophic bacteria		Mesophilic bacteria		H2S-producing bacteria		Pseudomonas spp.
	A	B	A	B	A	B	A	B
EU score	r = 0.9919	r = 0.9941	r = 0.9159	r = 0.9040	r = 0.9569	r = 0.9863	r = −	r = 0.7948
Cooked fish	r = −0.9874	r = −0.9890	r = −0.9572	r = −0.8735	r = −0.9786	r = −0.9614	r = −	r = −0.8829
Quality index	r = 0.9766	r = 0.9776	r = 0.8697	r = 0.8913	r = 0.9305	r = 0.9802	r = −	r = 0.7566
pH	r = 0.7241	r = 0.6877	r = 0.5630	r = 0.5131	r = 0.6193	r = 0.5983	r = −	r = 0.5768
TVB-N	r = −0.5511	r = −0.3367	r = −0.5663	r = −0.3661	r = −0.6055	r = −0.4629	r = −	r = −0.0503
TMA-N	r = 0.8377	r = 0.8992	r = 0.8717	r = 0.9652	r = 0.8733	r = 0.9093	r = −	r = 0.8702

Table 7 Changes in H₂S-producing bacteria of whole ungutted (A), gutted (B) sea bass stored in ice.

	H2S-producing bacteria (including Shewanella putrefaciens)
	Skin (log/CFU cm^2)		Abdominal cavity (log/CFU cm^2)		Flesh (log/CFU g)
Storage time	A	B	A	B	A	B
1	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.02)a	2.48 (± 0.01)a
3	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.95 (± 0.03)a	2.48 (± 0.01)a
5	2.96 (± 0.03)b	3.48 (± 0.02)b	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.02)a
7	3.78 (± 0.02)b	4.87 (± 0.01)b	2.48 (± 0.01)a	2.48 (± 0.01)a	4.44 (± 0.05)a	4.50 (± 0.06)a
9	4.78 (± 0.04)b	5.44 (± 0.03)b	3.48 (± 0.03)b	4.52 (± 0.04)b	4.84 (± 0.02)a	5.06 (± 0.04)a
11	5.82 (± 0.02)b	6.61 (± 0.04)b	3.48 (± 0.02)b	5.19 (± 0.06)b	4.56 (± 0.04)b	5.22 (± 0.02)b
13	6.07 (± 0.05)a	6.24 (± 0.03)a	5.17 (± 0.04)b	5.78 (± 0.03)b	5.60 (± 0.07)a	5.56 (± 0.09)a

Table 8 Changes in Psychrotrophic bacteria of whole ungutted (A), gutted (B) sea bass stored in ice.

	Psychrotrophic bacteria
	Skin (log/CFU cm^2)		Abdominal cavity (log/CFU cm^2)		Flesh (log/CFU g)
Storage time	A	B	A	B	A	B
1	2.51 (± 0.01)a	2.48 (± 0.03)a	2.50 (± 0.01)a	2.50 (± 0.01)a	2.51 (± 0.02)a	2.50 (± 0.01)a
3	3.11 (± 0.06)a	2.98 (± 0.01)a	2.50 (± 0.01)a	2.50 (± 0.01)a	2.51 (± 0.02)a	2.50 (± 0.01)a
5	3.51 (± 0.02)a	3.76 (± 0.05)a	2.51 (± 0.02)a	2.50 (± 0.01)a	2.50 (± 0.01)a	2.80 (± 0.04)a
7	4.47 (± 0.07)a	4.88 (± 0.01)a	3.11 (± 0.05)a	3.35 (± 0.06)a	3.91 (± 0.01)a	3.50 (± 0.01)a
9	5.21 (± 0.03)b	5.66 (± 0.07)b	4.91 (± 0.04)a	4.65 (± 0.01)a	5.37 (± 0.07)b	4.39 (± 0.05)b
11	6.68 (± 0.05)b	7.60 (± 0.10)b	5.63 (± 0.11)a	5.78 (± 0.05)a	5.75 (± 0.04)a	5.89 (± 0.03)a
13	7.38 (± 0.10)b	6.92 (± 0.05)b	5.64 (± 0.09)b	6.58 (± 0.03)b	6.01 (± 0.01)a	5.85 (± 0.01)a

Table 9 Changes in aerobic mesophilic count of whole ungutted (A), gutted (B) sea bass stored in ice.

	Aerobic mesophilic count
	Skin (log/CFU cm^2)		Abdominal cavity (log/CFU cm^2)		Flesh (log/CFU g)
Storage time	A	B	A	B	A	B
1	2.48 (± 0.01)a	3.26 (± 0.01)a	2.48 (± 0.02)a	2.48 (± 0.01)a	3.32 (± 0.01)b	2.48 (± 0.01)b
3	2.48 (± 0.01)a	2.48 (± 0.01)a	2.78 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	3.08 (± 0.01)a
5	2.48 (± 0.02)a	2.78 (± 0.03)a	2.48 (± 0.02)a	2.48 (± 0.01)a	2.96 (± 0.03)a	2.48 (± 0.01)a
7	2.96 (± 0.02)b	3.97 (± 0.04)b	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.02)b	3.66 (± 0.02)b
9	3.48 (± 0.05)a	3.48 (± 0.01)a	3.48 (± 0.01)a	3.96 (± 0.02)a	3.48 (± 0.02)a	4.26 (± 0.05)a
11	3.48 (± 0.03)b	4.48 (± 0.06)b	3.48 (± 0.03)a	3.78 (± 0.01)a	3.96 (± 0.04)b	4.91 (± 0.06)b
13	4.90 (± 0.01)a	5.10 (± 0.02)a	4.32 (± 0.02)a	4.52 (± 0.02)a	4.93 (± 0.03)b	5.84 (± 0.01)b

Table 10 Changes in Pseudomonas spp. of whole ungutted (A), gutted (B) sea bass stored in ice.

	Pseudomonas spp.
	Skin (log/CFU cm^2)		Abdominal cavity (log/CFU cm^2)		Flesh (log/CFU g)
Storage time	A	B	A	B	A	B
1	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a
3	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a
5	2.48 (± 0.01)a	2.48 (± 0.02)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.02)a
7	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.02)a	2.48 (± 0.01)a	2.48 (± 0.02)a
9	2.48 (± 0.01)a	2.48 (± 0.02)a	2.48 (± 0.02)a	2.48 (± 0.01)a	2.48 (± 0.01)a	2.48 (± 0.02)a
11	2.48 (± 0.01)b	3.26 (± 0.04)b	2.48 (± 0.01)a	2.96 (± 0.03)a	2.48 (± 0.01)b	3.26 (± 0.07)b
13	2.48 (± 0.01)b	3.80 (± 0.02)b	2.48 (± 0.01)b	3.69 (± 0.04)b	2.48 (± 0.01)b	3.48 (± 0.05)b