Effects of Gum Arabic Concentration and Soy Proteins on the Flow and Viscoelasticity of their Dispersion

Figures & data

Figure 1 Flow behavior of dispersions of (a) gum arabic (GA): (15%), (25%), (35%), (45%); and (b) soy protein (SP): (1%), (3%), (5%), (8%).

Table 1 Rheological parameters according to the Ostwald de Waele model for mixtures of gum arabic/soy protein (GA/SP), at varying concentrations

Dispersion GA/SP (%, w/v)	η ap (mPas)	K (mPas^n)	n	Increase of viscosity (%)
0/1	10 ± 2.4	499	0.385	—
0/3	12 ± 1.7	619	0.459	20
0/5	17 ± 3.9	676	0.470	70
0/8	54 ± 4.3	1916	0.470	440
15/0*	16 ± 0.16	—	—	—
15/1	18 ± 0.90	8	0.918	13
15/3	22 ± 0.23	15	0.920	38
15/5	22 ± 0.68	17	0.972	38
15/8	28 ± 0.60	31	0.974	75
25/0*	28 ± 0.81	—	—	—
25/1	41 ± 1.53	42	0.937	46
25/3	56 ± 0.29	67	0.945	100
25/5	68 ± 0.78	96	0.973	143
25/8	75 ± 3.49	112	0.949	168
35/0*	125 ± 0.34	—	—	----
35/1	127 ± 2.85	212	0.906	2
35/3	148 ± 4.37	237	0.922	18
35/5	204 ± 5.09	383	0.926	63
35/8	310 ± 0.67	352	0.978	148
45/0*	374 ± 4.37	—	—	—
45/1	377 ± 0.64	1291	0.775	1
45/3	491 ± 6.11	1307	0.818	31
45/5	725 ± 4.27	1693	0.852	94
45/8	1269 ± 6.54	2132	0.902	239
*Value according to Newton Law.
GA/SP = relationship gum arabic/soy protein; η ap = apparent viscosity; K = consistency coefficient; n = flow behavior index (dimensionless).

Figure 2 Amplitude sweep on the storage moduli (G′) and loss moduli (G″) for dispersions (a) GA at 15, 25, 35, and 45%; (b) SP at 1, 3, 5, and 8%; (c) GA/SP mixtures, 15% GA and up to 8% of SP; (d) GA/SP mixtures, 25% GA and up to 8% of SP; (e) GA/SP mixtures, 35% GA and up to 8% of SP; (f) GA/SP mixtures, 45% GA and up to 8% of SP.

Figure 3 Behavior of dynamic moduli (G′, G″) in function of the frequency in gum arabic/soy protein mixtures (GA/SP) with 15 and 25% of GA, and 0% SP (, ); 1% SP (, ); 3% SP (, ); 5% SP (, ); and 8% SP (, ).

Figure 4 Behavior of dynamic moduli (G′, G″) in function of the frequency in gum arabic/soy protein mixtures (GA/SP) with 35 and 45% of GA, and 0% SP (, ); 1% SP (, ; 3% SP (, ); 5% SP (, ); and 8% SP (, ).

Table 2 Dynamic parameters in gum arabic/soy protein mixtures (GA/SP) at varying concentrations. Dependency of G′ and G″ on the frequency

Dispersion GA/SP (%, w/v)	Torque amplitude (mNm)	G′ (Pa)	G″ (Pa)	tan δ
15/0	3.303	147 α ω^2.02	7 α ω^0.70	0.05
15/1	2.601	145 α ω^2.02	8 α ω^0.72	0.06
15/3	2.438	145 α ω^2.02	28 α ω^0.76	0.19
15/5	1.066	142 α ω^2.02	69 α ω^0.84	0.48
15/8	0.327	63 α ω^1.47	414 α ω^1.12	6.57
25/0	3.094	145 α ω^2.06	9 α ω^1.20	0.06
25/1	1.190	145 α ω^2.02	17 α ω^0.82	0.15
25/3	0.926	142 α ω^2.00	36 α ω^0.76	0.25
25/5	0.889	140 α ω^2.00	288 α ω^0.96	1.99
25/8	0.720	132 α ω^2.05	574 α ω^0.92	4.38
35/0	2.218	147 α ω^2.02	9 α ω^0.77	0.06
35/1	2.090	144 α ω^2.00	36 α ω^0.76	0.26
35/3	1.753	141 α ω^2.00	45 α ω^0.84	0.28
35/5	1.080	141 α ω^2.04	187 α ω^0.94	1.30
35/8	0.121	140 α ω^2.00	337 α ω^0.96	2.39
45/0	3.465	150 α ω^2.03	18 α ω^0.77	0.13
45/1	0.241	148 α ω^2.03	84 α ω^0.93	0.60
45/3	0.132	139 α ω^2.00	128 α ω^0.92	0.87
45/5	0.098	138 α ω^2.01	348 α ω^0.95	2.32
45/8	0.086	120 α ω^2.05	587 α ω^0.94	4.89
GA/SP = relationship gum arabic/soy protein; G′ = storage modulus; G″ = loss modulus; δ = phase angle.