Rheological Behaviors of Sumac Concentrate

Figures & data

Table 1 Analytical data for 70°Brix sumac concentrate

pH	3.2
Density (g/cm^3)	1.315
Hunter color values
L	2.43
a	4.47
b	0.36
Total phenolic matter as gallic acid (mg/l)	0.398
Monomeric anthocyanin content (mg/l)	325
Total moisture content (%)	28.53

Table 2 Parameters of the Hershley-Bulkey model describing dependency of viscosity TSS at different temperatures for sumac concentrate

TSS (°Brix)	Temperature (°C)	K (Pa.s^n)	n	σ0 (Pa)	R^2
70.0	20	2.4689 ± 0.110	0.8530 ± 0.008	3.0518 ± 0.860	0.9997
	30	0.9001 ± 0.004	0.9273 ± 0.008	1.5230 ± 0.440	0.9997
	40	0.4026 ± 0.020	0.9754 ± 0.009	0.7181 ± 0.260	0.9996
	50	0.1882 ± 0.010	1.0281 ± 0.0078	0.0996 ± 0.130	0.9998
60.0	20	0.1860 ± 0.010	1.0150 ± 0.009	0.0932 ± 0.130	0.9997
	30	0.1025 ± 0.010	1.0311 ± 0.010	0.0553 ± 0.100	0.9994
	40	0.0521 ± 0.020	1.0798 ± 0.010	0.1103 ± 0.060	0.9995
	50	0.0340 ± 0.030	1.0950 ± 0.014	0.1328 ± 0.010	0.9992
56.0	20	0.0806 ± 0.005	1.0579 ± 0.012	0.0767 ± 0.009	0.9994
	30	0.0440 ± 0.003	1.0845 ± 0.011	0.1366 ± 0.050	0.9994
	40	0.0521 ± 0.003	1.0798 ± 0.010	0.1103 ± 0.060	0.9995
	50	0.0340 ± 0.003	1.0950 ± 0.014	0.1328 ± 0.050	0.9992
50.0	20	0.0806 ± 0.005	1.0579 ± 0.012	0.0767 ± 0.009	0.9994
	30	0.0440 ± 0.003	1.0845 ± 0.011	0.1366 ± 0.050	0.9994
	40	0.0318 ± 0.004	1.0742 ± 0.021	0.1307 ± 0.070	0.9983
	50	0.0196 ± 0.020	1.1077 ± 0.020	0.1736 ± 0.050	0.9984

Figure 1 Flow behaviors of sumac concentrate with TSS of 70°Brix at different temperatures.

Figure 2 Changes of viscosity coefficient with total soluble solid at 20, 30, 40, and 50°C.

Figure 3 Changes of flow behavior index with total soluble solid at 20, 30, 40 and 50°C.

Table 3 Viscosity values of the sumac concentrate obtained from Newtonian model at different TSS and temperature

TSS (°Brix)	T (°C)	η (Pa.s)	r^2
70.0	20	118.0720	0.9914
	30	63.3392	0.9984
	40	35.5431	0.9995
	50	21.8728	0.9992
60.0	20	20.2211	0.9995
	30	11.7761	0.9988
	40	7.9385	0.9979
	50	5.6323	0.9974
56.0	20	10.6651	0.9984
	30	6.8922	0.9979
	40	7.9385	0.9979
	50	5.6347	0.9974
50.0	20	10.6651	0.9984
	30	6.9922	0.9979
	40	4.7634	0.9974
	50	3.5296	0.9970

Table 4 Parameters of the power law model describing dependency of viscosity on TSS at different temperatures for sumac concentrate

Temperature (°C)	η1(mPa.s)	b1(°Brix)	R^2
20	4.308 × 10^−19	1.167 × 10^1	0.9969
30	3.488 × 10^−17	1.047 × 10^1	0.9956
40	5.359 × 10^−16	9.684 × 10^0	0.9947
50	3.069 × 10^−14	8.613 × 10^0	0.9931

Table 5 Parameters of the exponential model describing dependency of viscosity on TSS at different temperatures for sumac concentrate

Temperature (°C)	η2 (mPa.s)	b2(°Brix)	R^2
20	1.882 × 10^−3	1.942 × 10^−1	0.9986
30	3.753 × 10^−3	1.742 × 10^−1	0.9979
40	7.945 × 10^−3	1.548 × 10^−1	0.9969
50	1.643 × 10^−2	1.372 × 10^−1	0.9961

Table 6 Parameters of Arrhenius equation for sumac concentrate with different total soluble solids

TSS (°Brix)	η∞(mPa.s)	Ea × 10^3 (kj/mol)	R^2
50.0	2.272 × 10^−3	24.78	0.9965
56.0	3.825 × 10^−4	30.55	0.9946
60.0	1.116 × 10^−4	35.05	0.9968
70.0	2.581 × 10^−6	48.72	0.9989