Physicochemical, Morphological, Pasting, and Rheological Properties of Tamarind (Tamarindus indica L.) Kernel Starch

Figures & data

TABLE 1 Amylose content, swelling power, solubility and light transmittance of tamarind kernel, corn, and mung bean starches

Parameter	Tamarind kernel starch	Corn starch	Mung bean starch
Amylose content (g/100g)	14.2^a ± 0.09	18.3^b ± 0.10	25.7^c ± 0.12
Swelling power (g/g) at 90°C	19.2^b ± 0.15	16.3^a ± 0.29	16.8^a ± 0.18
Solubility (g/100g) at 90°C	6.2^a ± 0.06	18.3^b ± 0.09	20.1^c ± 0.08
Light transmittance (%)	2.2^a ± 0.09	3.7^b ± 0.09	11.1^c ± 0.09

Mean ± SD with different superscripts in a row differ significantly (p < 0.05; n = 3).

FIGURE 1 Scanning electron micrographs of tamarind kernel starch.

FIGURE 2 X-ray diffraction pattern of tamarind kernel starch.

TABLE 2 Pasting properties of tamarind kernel, corn, and mung bean starches

Starch source	Peak viscosity (cP)	Trough viscosity (cP)	Breakdown viscosity (cP)	Final viscosity (cP)	Set back (cP)	Pasting temperature (°C)
Tamarind kernel	2163^c ± 0.09	1805^c ± 0.09	358^c ± 0.09	2173^b ± 0.09	368^a ± 0.09	72.4^b ± 0.09
Corn	1529^a ± 0.09	1319^a ± 0.09	210^b ± 0.09	1698^a ± 0.09	379^a ± 0.09	73.0^c ± 0.09
Mung bean	1857^b ± 0.09	1746^b ± 0.09	111^a ± 0.09	3697^c ± 0.09	1951^b ± 0.09	68.9^a ± 0.09

Mean ± SD with different superscripts in a row differ significantly (p < 0.05; n = 3).

TABLE 3 Rheological properties of tamarind kernel, corn, and mung bean starches

Starch source	Peak Gʹ (Pa)	Peak Gʹʹ (Pa)	tan δ	Breakdown in Gʹ (Pa)	TGʹ (°C)
Tamarind kernel	2295^a ± 0.09	517^c ± 0.09	0.22^c ± 0.09	590^a ± 0.09	77.5^b ± 0.09
Corn	3200^c ± 0.09	285^a ± 0.09	0.08^a ± 0.09	1139^b ± 0.09	75.0^a ± 0.09
Mung bean	2708^b ± 0.09	458^b ± 0.09	0.16^b ± 0.09	1491^c ± 0.09	75.0^a ± 0.09

Mean ± SD with different superscripts in a row differ significantly (p < 0.05; n = 3).

FIGURE 3 (A) Changes in G′ for starches during heating; (B) Changes in G″ for starches during heating; (C) Changes in tan δ for starches during heating.

FIGURE 4 (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 G′ at 95°C for starches; (D) Angular frequency dependence of G″ at 95°C for starches.

FIGURE 5 (A) Changes in G′ for starches during cooling, holding at 10°C for 10 h and heating; (B) Changes in G′ during holding at 10°C for 10 h for starches.