Texture characteristics of chilled prepared Mandarin fish (Siniperca chuatsi) during storage

Figures & data

Figure 1. Total volatile basic nitrogen (TVBN) (mg /100 g fish muscle) of fish during cold storage at 4°C.

Table 1. Texture changes in raw and cooked fish during cold storage at 4°C.

Time (day)		1	2	3	4	5
Raw	Hardness (g)	3145 ± 301^a	2739 ± 318^b	2493 ± 302^c	1498 ± 293^d	958 ± 186^e
	Springiness	0.7 ± 0.1^a	0.7 ± 0.1^ab	0.64 ± 0.09^bc	0.6 ± 0.1^cd	0.5 ± 0.1^de
	Cohesiveness	0.50 ± 0.05^a	0.49 ± 0.07^a	0.49 ± 0.06^a	0.47 ± 0.05^a	0.48 ± 0.06^a
	Gumminess (g)	1574 ± 168^a	1351 ± 208^b	1214 ± 198^b	710 ± 151^c	464 ± 105^d
	Chewiness (g)	1163 ± 193^a	982 ± 227^b	784 ± 168^c	417 ± 105^d	255 ± 80^e
Cooked	Hardness (g)	572 ± 190^a	349 ± 60^b	341 ± 106^b	340 ± 116^b	285 ± 116^b
	Springiness	1.0 ± 0.4^a	0.9 ± 0.2^ab	0.9 ± 0.5^ab	0.9 ± 0.3^ab	0.77 ± 0.08^b
	Cohesiveness	0.4 ± 0.1^c	0.63 ± 0.09^a	0.6 ± 0.1^a	0.6 ± 0.1^ab	0.5 ± 0.1^b
	Gumminess (g)	261 ± 124^a	220 ± 53^a	210 ± 73^a	219 ± 116^a	157 ± 83^b
	Chewiness (g)	245 ± 118^a	207 ± 88^ab	193 ± 136^ab	197 ± 133^ab	124 ± 70^b

a-e: Values with unlike superscript letters in the same line are significantly different (P < 0.05).

Figure 2. Changes in TCA-soluble peptide contents of fish during cold storage at 4°C.

Figure 3. SDS-PAGE patterns of fish during cold storage at 4°C. Numbers designate the storage time (days). Marker: molecular weight marker.

Table 2. Moisture content, cooking loss, and centrifugal loss of fish during cold storage at 4°C.

Time (day)	1	2	3	4	5
Moisture content (%)	82.5 ± 0.1^b	83.5 ± 0.2^a	83.4 ± 0.4^a	83.3 ± 0.3^a	82.2 ± 0.4^b
Cooking loss (%)	10 ± 2^b	10.3 ± 0.3^ab	11 ± 1^ab	9 ± 1^b	11.8 ± 0.7^a
Centrifugation loss (%)	11.5 ± 0.2^e	14.0 ± 0.2^d	15.5 ± 0.3^c	16.00 ± 0.08^b	16.6 ± 0.2^a

a-e: Values with unlike superscript letters in the same line are significantly different (P < 0.05).

Figure 4. Typical NMR T2 curve of fish during cold storage at 4°C. P1, bound water; P2, immobilized water; P3, free water.

Figure 5. The changes in A2(a) and T2(b) of fish during cold storage at 4°C.

Table 3. PPMCCs of NMR (A₂₁, A₂₂, A₂₃, T₂₁, T₂₂, T₂₃) and texture (hardness, springiness, cohesiveness, gumminess, and chewiness).

PPMCC	A21	A23	A23	T21	T22	T23
Hardness	0.723	0.957	0.342	0.302	0.933	0.664
Springiness	0.809	0.965	0.221	0.501	0.966	0.720
Cohesiveness	0.650	0.877	0.127	0.010	0.799	0.730
Gumminess	0.736	0.960	0.319	0.306	0.935	0.683
Chewiness	0.780	0.970	0.253	0.364	0.948	0.727

A₂₁, A₂₂, A₂₃ represent the water content of bound water, immobilized water and free water, respectively.

PPMCC: Pearson product-moment correlation coefficient; NMR: nuclear magnetic resonance.

Figure 6. Intermolecular bonds changes of fish during cold storage at 4°C.

Table 4. PPMCCs of immobilized water and intermolecular bonds (hydrophobic interactions and disulfide bonds).

PPMCC	Hydrophobic interactions	Disulfide bonds
A22	−0.903	−0.870
T22	−0.910	−0.866

PPMCC: Pearson product-moment correlation coefficient.