Incorporating iron fortificant in ultrasonicated waxy rice led to its stickier and firmer characteristics

Figures (6) Tables (2)

Figure 1.
Postharvest iron fortification of waxy rice using ultrasonic treatment.
Figure 2.
Photographs of raw, sonicated, and iron-soaked (non-sonicated and sonicated) IR65 rice.
Figure 3.
Iron content of uncooked and cooked fortified rice. Values with different letters are significantly different (* p < 0.01).
Figure 4.
Textural properties of cooked raw and iron-fortified IR65 rice. (a) Hardness, (b) stickiness, (c) cohesiveness, (d) springiness, (e) gumminess, (f) chewiness. Values with different letters are significantly different (* p < 0.01, ** p < 0.05).
Figure 5.
Dynamic shear curves of IR65 rice samples during temperature ramp experiment showing (a) elastic (G') and viscous moduli (G"); and (b) tan δ. For the color version of the figure, the reader is referred to the online version of this article.
Figure 6.
Dynamic viscoelasticity of IR65 as a function of frequency.

	Samples
	Raw IR65	Iron soaked IR65	Sonicated iron-fortified IR65
Heating
G'_max	333.73 ± 79.11^a	760.50 ± 145.24^b**	833.23 ± 199.95^b*
G"_max	107.84 ± 14.34^a	175.57 ± 30.09^a	194.43 ± 39.46^b**
tan δ_G'max	0.33 ± 0.04^a	0.23 ± 0.01^a	0.23 ± 0.01^a
G'_95°C	264.17 ± 23.05^a	405.33 ± 56.47^b**	456.20 ± 59.25^b*
G"_95°C	76.58 ± 2.23^a	88.88 ± 14.52^a	98.74 ± 0.71^b**
tan δ_95°C	0.29 ± 0.02^a	0.22 ± 0.01^b*	0.22 ± 0.01^b*
Cooling
G'_35°C	329.53 ± 12.26^a	474.27 ± 69.27^b**	529.03 ± 37.37^b*
G"_35°C	93.62 ± 2.82^a	111.29 ± 11.82^b**	127.97 ± 6.33^b*
tan δ_35°C	0.28 ± 0.00^a	0.24 ± 0.01^b*	0.24 ± 0.01^b*
Data presented as mean ± standard deviation of duplicate determinations. Values with different letters in the same group are significantly different (* p < 0.01, ** p < 0.05).

Table 1.

Dynamic rheological properties of waxy rice in the presence of FeSO₄.

Samples	Consistency index (K)	Flow behavior index (n)
Raw IR65	6.80 ± 0.77^a	0.030 ± 0.00^a
Iron soaked IR65	6.98 ± 2.99^a,b	0.037 ± 0.01^a
Sonicated iron-fortified IR65	13.0 ± 1.33^b	0.027 ± 0.00^a
Data presented as mean ± standard deviation of duplicate determinations. Values with different letters in the same group are significantly different.

Table 2.

Derived parameters from frequency sweep experiment of IR65 rice samples.