Development of a quality index method (QIM) scheme for whole Goldlined seabream Rhabdosargus sarba stored in ice

Figures & data

Table 1. QIM scheme for assessing whole ice storage Goldlined seabream Rhabdosargus sarba.

Quality attributes	Parameter	Characteristics	Score
Overall appearance	Skin	Bright/Vivid and defined/Glossy/Brightness intense	0
		Slightly bright/discoloration on the side/Brightness loss/Partially glossy	1
		Loss of glossiness/Dull/pale/wrinkled or failed skin/opaque	2
	Texture	Firm/Elastic/Finger mark disappears rapidly	0
		Soft/Flabby/finger mark delays disappear	1
Eye	Cornea	Clear and crystalline	0
		Clear or slightly cloudy	1
		Opaque	2
	Pupil	Slightly opaque/Absence of a white spot	0
		Opaque/small white spot	1
		Gray opaque/large white spot	2
	Shape	Convex/Protuberant	0
		Flat/Plane	1
		Sunk/Concave	2
	Eyeball	Intact	0
		Detached	1
Gill	Color	Bright red/Slightly viscous	0
		Red/Some viscous	1
		Reddish pink keen brown/Some viscous	2
	Odor	Fresh/Specific species	0
		Destruction of fish specific smell/neutral	1
		Low and medium rancidity	2
		High rancidity/Stinking	3
Fins	Dorsal/Ventral/Caudal	Full/Wet/With elasticity	0
		Full/resected tips/with low elasticity	1
		Failed/resected tips/no elasticity	2
Caudal fin	Moisture	Totally moist	0
		Dry on the edge	1
		Totally dry	2
	Color	Light	0
		Dark	1
Dorsal	Elasticity	Elastic	0
		Inelastic	1
	Color	Dark green	0
		Light green	1
		Light blue and dark	2
Abdomen (Internal)	Color	Fresh color/bright red blood	0
		Yellowish pink flesh/dark red blood	1
		Brownish pink or darkened/Brown blood	2
	Odor	Fresh or neutral	0
		Rancid/Slightly ammonium	1
		Putrid	2
Abdomen (outside)	Overall aspect	Flexible/shiny/Moist	0
		Loss of elasticity/Slightly discolored	1
		Inelastic/Dry/Discolored	2
Flesh	Color	Dark and bright red	0
		Bright red	1
		Pale red or brownish/discolored	2
	Odor	Fresh or neutral	0
		Rancid/Slightly ammonium	1
		Putrid	2
	Firmness	Firm/Compact	0
		Soft/Crumbling	1
Total QIM Score			0–34

Figure 1. Linear correlation between QIM and storage time of Goldlined seabream Rhabdosargus sarba during the ice storage.

Figure 2. Partial least squares (PLS) regression for quality index method (QIM) of Goldlined seabream Rhabdosargus sarba during the ice storage and the predicted values.

Figure 3. Average scores for each quality parameters assessed with the QIM scheme for Goldlined seabream Rhabdosargus sarba stored in ice and the correlation to days in ice: (A) Overall appearance; (B) Eye (C) Gill (D) Fins (E) Caudal fin (F) Dorsal (G) Abdomen (Internal) (H) Abdomen (outside) (I) Flesh.

Table 2. Microbiological evaluation of Goldlined seabream Rhabdosargus sarba during ice storage (log CFU/g).

Days of storage	0	3	6	9	12	r
Mesophilic bacteria	4.27 ± 0.01^b	4.67 ± 0.27^b	4.71 ± 0.27^b	7.17 ± 0.01^a	7.39 ± 0.11^a	0.900*
Psychrotrophilic bacteria	2.62 ± 0.03^e	5.88 ± 0.03^d	6.39 ± 0.00^c	7.32 ± 0.01^b	7.83 ± 0.03^a	0.918*
Enterobacteriaceae	2.99 ± 0.02^e	4.35 ± 0.09^d	5.31 ± 0.37^c	6.44 ± 0.13^b	7.13 ± 0.00^a	0.979*

Data within the same row with different letters are significantly different (p < 0.05).

* indicates a significant correlation (p < 0.05).

Table 3. Goldlined seabream Rhabdosargus sarba physicochemical parameter changes during ice storage.

Days of storage	0	3	6	9	12	r
TVBN (mg N/100g muscle)	4.90 ± 1.21^b	6.30 ± 0.40^b	28.00 ± 1.61^a	21.00 ± 0.80^a	32.20 ± 8.89^a	0.782*
pH	6.67 ± 0.04^c	6.86 ± 0.02^ab	6.84 ± 0.02^ab	6.96 ± 0.06^a	6.78 ± 0.02^bc	0.410
TBARS (mg MDA/kg muscle)	0.20 ± 0.02^c	0.56 ± 0.17^bc	0.68 ± 0.15^b	1.39 ± 0.07^a	0.31 ± 0.04^c	0.331
FFA (% oleic acid)	2.13 ± 0.34^b	5.32 ± 0.33^ab	1.76 ± 0.07^b	5.15 ± 0.49^ab	7.46 ± 2.75^a	0.531*

Data within the same row with different letters are significantly different (p < 0.05).

* indicates a significant correlation (p < 0.05).

Table 4. Goldlined seabream Rhabdosargus sarba color parameters (a*, b*, L*, C*_ab, H^º_ab, W) changes during ice storage.

Days of storage	0	3	6	9	12	r
a*	10.04 ± 0.33^ab	8.07 ± 0.85^b	8.23 ± 1.02^b	13.03 ± 01.83^a	10.14 ± 1.05^ab	0.304
b*	16.87 ± 1.81^ab	14.50 ± 0.41^ab	16.96 ± 0.29^ab	17.91 ± 0.81^a	14.92 ± 0.59^b	−0.036
L*	56.90 ± 0.88^a	53.38 ± 3.86^a	54.47 ± 2.25^a	56.71 ± 1.54^a	44.17 ± 4.06^b	−0.510
C*ab	19.65 ± 1.72^abc	16.60 ± 0.77^c	20.80 ± 1.88^ab	22.31 ± 0.42^a	18.12 ± 0.11^bc	0.142
H^ºab	1.02 ± 0.03^a	1.06 ± 0.03^a	1.10 ± 0.06^a	0.94 ± 0.08^a	0.97 ± 00.06^a	−0.311
W	52.60 ± 1.51^a	50.16 ± 4.19^ab	49.86 ± 2.29^ab	51.29 ± 1.55^a	41.27 ± 3.89^b	−0.529*

Data within the same row with different letters are significantly different (p < 0.05).

* indicates a significant correlation (p < 0.05).

Table 5. Rotated factor loading matrix (VARIMAX) for the community attributes and values and factor statistics.

Time of storage		Factor 1	Factor 2	Factor 3	Factor 4	Factor	(%) Total variance	(%) Cumulative
Time of storage		0.917	−-0.037	0.326	0.229	1 2 3 4	41.602 22.126 19.529 16.743	41.602 63.728 83.257 100.000
Chemical analysis	TVBN	0.978	0.200	0.046	0.033
	pH	0.248	0.109	0.097	0.958
	TBA	0.099	0.447	0.267	0.848
	FFA	0.481	−0.646	0.555	0.207
color	a*	0.104	0.444	0.867	0.203
	b*	−0.115	0.968	0.179	0.132
	C*ab	0.120	0.949	0.202	0.209
	H^ºab	−0.226	−0.057	−0.971	−0.062
	L*	−0.747	0.592	−0.091	0.290
	W	−0.827	0.483	−0.135	0.256
Microbiological analysis	TMC	0.703	−0.025	0.673	0.227
	PTC	0.820	−0.158	0.115	0.538
	Enterobacteriaceae	0.895	−0.027	0.303	0.327
QIM		0.918	−0.022	0.285	0.275