Emulsifying Properties of Cross-Linking Between Proteins Extracted from Cold/Hot Pressed Peanut Meal and Hydrolysed Fish (Decapterus Maruadsi) Proteins

Figures & data

Figure 1  SDS-PAGE profile of samples without (lanes 1, 2, 5, 6) and with (lanes 3, 4, 7, 8) TGase treatment. Lane M: Molecular markers; Lane 1: CPPP; Lane 2: mMixture of CPPP and DPH; Lane 3: cCross-linked CPPP; Lane 4: cCross-linked CPPP and DPH; Lane 5: HPPP; Lane 6: mMixture of HPPP and DPH; Lane 7: cCross-linked HPPP; Lane 8: cCross-linked HPPP and DPH (CPPP: cold-pressed peanut protein; HPPP: hot-pressed peanut protein; DPH: Decapterus maruadsi hydrolysates).

Table 1  The amino acid composition of CPPP, HPPP, and DPH

	Composition (g amino acid/100 g protein)
Amino acids	CPPP	HPPP	DPH
Asp^a	12.0 ± 1.1	11.1 ± 0.9	8.8 ± 0.8
Glu^b	22.1 ± 1.9	22.8 ± 2.1	15.8 ± 1.6
Ser	4.9 ± 0.4	4.5 ± 0.3	4.0 ± 0.3
Gly	4.4 ± 0.7	4.1 ± 0.2	6.0 ± 0.8
His	2.0 ± 0.3	2.4 ± 0.4	7.2 ± 0.6
Arg	12.1 ± 1.4	11.0 ± 1.5	6.9 ± 0.4
Thr	2.4 ± 0.2	2.2 ± 0.3	4.3 ± 0.3
Ala	3.7 ± 0.5	3.1 ± 0.2	6.5 ± 0.7
Pro	4.1 ± 0.3	4.6 ± 0.5	4.0 ± 0.5
Tyr	4.3 ± 0.4	4.0 ± 0.3	3.1 ± 0.4
Val	3.7 ± 0.2	3.2 ± 0.4	4.6 ± 0.4
Met	0.9 ± 0.1	0.8 ± 0.1	2.7 ± 0.3
Cys	0.7 ± 0.2	0.4 ± 0.1	0.4 ± 0.1
Ile	3.1 ± 0.5	2.8 ± 0.3	3.7 ± 0.3
Leu	5.3 ± 0.4	5.6 ± 0.2	6.7 ± 0.5
Phe	5.2 ± 0.3	4.8 ± 0.5	3.1 ± 0.3
Lys	2.8 ± 0.2	2.0 ± 0.2	8.9 ± 0.6

^aAspartic acid + asparagine. ^bGlutamic acid + glutamine.

Figure 2  Particle size distribution of the emulsions made with (a) CPPP samples and (b) HPPP samples.

Figure 3  Effect of TGase treatment on the mean particle size d₃₂ of emulsions. The columns having the same letter are insignificantly different (p > 0.05).

Figure 4  Microscopic structure of emulsions made with samples without (a, c, e, g) or with TGase (b, d, f, h) treatment observed by optical microscope at a magnification of 400×: (a) and (b), are cold-pressed peanut protein; (c) and (d), are hot-pressed peanut protein; (e) and (f), are cold-pressed peanut protein and Decapterus maruadsi hydrolysates; (g) and (h), are hot-pressed peanut protein and Decapterus maruadsi hydrolysates.

Figure 5  The changes in the mean particle size d₄₃ of emulsions made with samples stored at room temperature for 20 days. The columns having the same letter are insignificantly different (p > 0.05).

Figure 6  The changes in the creaming rate of emulsions made with samples stored at room temperature for 20 days. The columns having the same letter are insignificantly different (p > 0.05).