Silver Carp (Hypophthalmichthys molitrix) Surimi Acid-Induced Gel Extract Characteristics: A Comparison with Heat-Induced Gel

Figures & data

FIGURE 1 Protein solubility of silver carp surimi in water with or without 3% NaCl as related to pHs.

TABLE 1 Moisture content, pH, breaking force, and deformation of acid- and heat-induced gels from silver carp surimi

	Acetic acid concentration (%)	Moisture content (%)	pH	Breaking force (g)	Deformation (mm)
Acid-induced gel	1	81.73 ± 0.22^d	4.80 ± 0.05^c	250.54 ± 15.49^b	11.23 ± 1.07^a
	2	81.12 ± 0.07^c	4.51 ± 0.04^b	315.14 ± 28.49^c	14.33 ± 1.35^b
	3	81.00 ± 0.11^c	4.26 ± 0.04^a	320.78 ± 18.49^c	15.72 ± 1.47^b
	4	80.74 ± 0.04^b	4.27 ± 0.05^a	305.36 ± 22.49^c	15.45 ± 1.36^b
Heat-induced gel (control)		79.01 ± 0.23^a	6.82 ± 0.05^d	199.49 ± 20.88^a	10.92 ± 1.32^a

Note: Any two means in the same column followed by the same letter are not significantly different (p > 0.05). Data are expressed as mean ± standard deviation.

FIGURE 2 SDS-PAGE of soluble protein fractions from silver carp surimi at different pHs with or without salt. M: Standard molecular weight mixture.

FIGURE 2 SDS-PAGE of soluble protein fractions from silver carp surimi at different pHs with or without salt. M: Standard molecular weight mixture.

TABLE 2 Color values (L*, a*, b*) and whiteness of acid- and heat-induced gels from silver carp surimi

	Acetic acid concentration (%)	L*	a*	b*	Whiteness
Acid-induced gel	1	67.53 ± 0.53^ab	−2.87 ± 0.56^a	0.43 ± 0.17^a	67.40 ± 0.51^ab
	2	68.46 ± 0.64^b	−3.02 ± 0.43^a	0.42 ± 0.22^a	68.31 ± 0.47^b
	3	70.37 ± 0.79^c	−3.00 ± 0.23^a	0.37 ± 0.14^a	70.22 ± 0.64^c
	4	70.82 ± 0.86^c	−2.97 ± 0.37^a	0.30 ± 0.11^a	70.67 ± 0.72^c
Heat-induced gel (control)		66.48 ± 0.70^a	−2.75 ± 0.72^a	1.70 ± 0.34^b	66.32 ± 0.73^a

Note: Any two means in the same column followed by the same letter are not significantly different (p > 0.05). Data are expressed as mean ± standard deviation.

FIGURE 3 The expressible water content of acid- and heat-induced gels from silver carp surimi. Con: Heat-induced surimi gel.

FIGURE 4 SDS-PAGE patterns of surimi paste, heat-induced surimi gel, and acid-induced gel. M: Standard molecular weight mixture; 1: Surimi paste; 2: Heat-induced surimi gel; 3: acid-induced gel.

FIGURE 5 SDS-PAGE of soluble protein fractions of surimi paste, heat-, and acid-induced gel in different protein denaturant solutions. M: Standard molecular weight mixture; 1: Surimi paste; 2: Heat-induced surimi gel; 3: acid-induced gel.

FIGURE 6 SEM images of (A) surimi pastes, (B) heat-induced surimi gels, and (C) acid-induced surimi gels (5000× magnifications).