Rheological and structural properties of starches from different Indian wheat cultivars and their relationships

Figures & data

Table 1. Amylose content, swelling power, and solubility of starches from different wheat cultivars.

	Cultivars
Parameter	C-306	PBW-373	WH-147	WH-1025	PBW-343	PBW-502
Amylose content (%)	18.35^a ± 0.33	18.78^a ± 0.67	20.10^b ± 0.27	18.92^a ± 0.20	19.35^ab ± 0.27	20.58^b ± 0.27
Swelling power (g/g)	12.22^bc ± 1.25	11.81^b ± 0.38	9.27^a ± 0.71	13.35^c ± 0.31	12.52^bc ± 0.04	12.57^bc ± 0.06
Solubility (%)	6.82^a ± 2.11	10.13^bc ± 0.15	6.48^a ± 0.26	9.10^b ± 0.90	11.98^c ± 0.21	9.72^b ± 0.26

The values expressed are means of n = 3 ± standard deviation.

Means in the rows with superscripts viz. a–c are significantly different at p ≤ 0.05.

Table 2. Light transmittance (%) property of starches isolated from different wheat cultivars.

	Cultivars
Time (h)	C-306	PBW-373	WH-147	WH-1025	PBW-343	PBW-502
0	11.65^aq ± 0.03	11.30^aq ± 0.03	13.39^bq ± 0.002	15.13^cq ± 0.04	13.28^bq ± 0.001	13.11^bq ± 0.002
24	4.64^cq ± 0.01	3.62^bq ± 0.01	2.51^aq ± 0.01	5.04^cq ± 0.02	4.67^cq ± 0.003	6.86^dq ± 0.002
48	2.71^ap ± 0.001	2.08^ap ± 0.001	1.57^ap ± 0.002	2.85^ap ± 0.003	2.63^ap ± 0.002	2.85^ap ± 0.004
72	1.91^ap ± 0.003	1.74^ap ± 0.01	1.36^ap ± 0.01	2.31^ap ± 0.01	2.28^ap ± 0.01	2.39^ap ± 0.001
96	1.66^ap ± 0.003	1.63^ap ± 0.001	1.31^ap ± 0.003	1.98^ap ± 0.02	2.10^ap ± 0.004	2.18^ap ± 0.01
120	1.54^ap ± 0.004	1.54^ap ± 0.002	1.27^ap ± 0.001	1.91^ap ± 0.01	1.99^ap ± 0.004	2.04^ap ± 0.002

The values expressed are means of n = 3 ± standard deviation.

Means in the rows with superscripts viz. a–d and columns with superscripts viz. p–q are significantly different at p ≤ 0.05.

Figure 1. Scanning electron micrographs of starches from different wheat cultivars. (A) C-306, (B) PBW-373, (C) WH-147, (D), WH-1025, (E) PBW-343, and (F) PBW-502.

Table 3. Structural characteristics of different wheat cultivar starches as determined by XRD and FTIR.

Cultivar	Diffraction spacing (d-spacing) (Å) at 2θ angle (°)					CI (%)	IR ratio 1047/1022	IR ratio 1022/995
C-306	5.88 (15.04)	5.17 (17.12)	4.95 (17.90)	4.44 (19.96)	3.89 (22.86)	31.37	0.8666	1.1117
PBW-373	NA	NA	4.90 (18.08)	4.40 (20.14)	3.87 (22.98)	26.61	0.8312	1.1808
WH-147	5.84 (15.16)	5.16 (17.16)	4.92 (18.02)	4.44 (19.98)	3.86 (23.00)	31.01	0.8470	1.1666
WH-1025	5.91 (15.00)	5.20 (17.06)	4.96 (17.88)	NA	3.89 (22.84)	30.43	0.8496	1.1115
PBW-343	5.85 (15.12)	5.08 (17.44)	NA	4.42 (20.06)	3.87 (22.96)	28.21	0.8385	1.1913
PBW-502	5.85 (15.12)	5.17 (17.12)	4.93 (17.96)	4.44 (19.96)	3.87 (22.96)	31.10	0.8493	1.1786

NA: not available; CI: crystalline index; and IR: infrared.

Figure 2. X-ray diffraction patterns of starches from different wheat cultivars at 2 θ (4–30°).

Figure 3. FTIR spectroscopy of starches from different wheat cultivars. (A) FTIR spectra from 400 to 4000 cm⁻¹. (B) Deconvoluted FTIR spectra from 800 to 1200 cm⁻¹.

Figure 4. Pasting curves of starches from different wheat cultivars. (A) C-306, (B) PBW-373, (C) WH-147, (D) WH-1025, (E) PBW-343, and (F) PBW-502.

Table 4. Dynamic rheological properties of starches isolated from different wheat cultivars.

	Cultivars
Parameters	C-306	PBW-373	WH-147	WH-1025	PBW-343	PBW-502
Rheological properties during heating
Peak Gʹ (Pa)	8924^b ± 257.39	8912^b ± 246.07	9067^b ± 270.11	8481^b ± 251.73	5674^a ± 162.63	5052^a ± 168.29
Peak Gʹʹ (Pa)	874^b ± 10.54	1064^d ± 11.55	885^b ± 11.38	1025^c ± 12.93	563^a ± 7.52	1463^e ± 13.79
Breakdown in Gʹ (Pa)	2503^c ± 18.17	3567^d ± 23.05	2556^c ± 19.80	2368^b ± 17.82	931^a ± 11.48	909^a ± 11.53
tan δ	0.10^a ± 0.002	0.12^a ± 0.002	0.10^a ± 0.002	0.12^a ± 0.002	0.10^a ± 0.002	0.29^b ± 0.007
TGʹ (°C)	77.58^a ± 0.17	80.09^b ± 0.16	77.57^a ± 0.14	77.57^a ± 0.14	82.58^c ± 0.21	85.06^d ± 0.23
Rheological properties at 6.28 rad/s at 25 °C
Gʹ (Pa)	5685^a ± 148.49	7370^c ± 188.09	6094^ab ± 186.68	6416^b ± 134.35	6860^bc ± 152.74	6818^b ± 151.32
Gʹʹ (Pa)	320^b ± 5.94	360^c ± 6.51	290^a ± 3.25	352^c ± 5.44	348^c ± 5.59	347^c ± 6.15
tan δ	0.06^d ± 0.0004	0.05^a ± 0.0004	0.05^a ± 0.001	0.05^c ± 0.0003	0.05^b ± 0.0003	0.05^b ± 0.0002
η* (Pa s)	906^a ± 10.61	1174^e ± 12.16	971^b ± 9.76	1022^c ± 11.31	1093^d ± 11.46	1086^d ± 11.17

Values expressed are means of n = 3 ± standard deviation. Means in the rows with different superscript (a–e) are significantly different at p ≤ 0.05.

Peak Gʹ: storage modulus; peak Gʹʹ: loss modulus; tan δ: damping factor (Gʹʹ/Gʹ); and TGʹ: temperature at peak Gʹ; Gʹ: storage modulus; Gʹʹ: loss modulus; η*: complex viscosity; and Pa: Pascal.

Figure 5. (A): Changes in G’ for wheat cultivar starches during heating. (B): Changes in G” for starches during heating. Here: (A) C-306, (B) PBW-373, (C) WH-147, (D) WH-1025, (E) PBW-343, and (F) PBW-502.

Figure 6. (A): Angular frequency dependence of G’ at 25 °C for starches; (B): angular frequency dependence of G” at 25 °C for starches; (C) angular frequency dependence of tan δ at 25 °C for starches. Here: (A) C-306, (B) PBW-373, (C) WH-147, (D) WH-1025, (E) PBW-343, and (F) PBW-502.

Table 5. The power law function parameters of different wheat cultivar starches.

Cultivar	K (Pa s)	n	R^2
C-306	33.44^a ± 2.19	0.25^ab ± 0.02	0.999
PBW-373	42.43^a ± 2.97	0.24^a ± 0.02	0.999
WH-147	56.40^b ± 4.26	0.25^ab ± 0.02	0.992
WH-1025	53.19^b ± 4.44	0.23^a ± 0.02	0.999
PBW-343	37.74^a ± 4.03	0.32^b ± 0.03	0.984
PBW-502	62.03^b ± 5.44	0.22^a ± 0.02	0.991

Values expressed are means of n = 3 ± standard deviation. Means in the column with different superscript (a–b) are significantly different at p ≤ 0.05.

K: Consistency coefficient; n: flow behavior indices; and R²: coefficients of determination.