Color Characteristics of Carrots: Effect of Drying and Rehydration

Figures & data

Figure 1 Effect of drying and rehydration on (a) color parameters: L*, a*, b*; (b) color indices: ΔE*, ΔC*, ΔH*. Means ± standard error.

Table 1 The statistical analyses of the main effects (drying and rehydration) on the color parameters (L*, a*, b*) of processed carrots

Sample	L*	a*	b*
D60	—	x	x
D70	—	x	x
D80	—	x	x
D90	x	x	x
R60	—	x	x
R70	—	x	x
R80	x	x	x
R90	x	x	x
x = significant difference between the experimental and reference samples (p ≤ 0.05).

Figure 2 Kinetic changes of color parameter: (a) a* (redness); (b) b* (yellowness); and (c) L* (lightness) for carrot cubes during drying. Means ± standard error.

Figure 3 Kinetic changes of color indices: (a) ΔE* (total color difference); (b) ΔC* (total saturation difference); and (c) ΔH* (total hue difference) for carrot cubes during drying. Means ± standard error.

Table 2 The parameters of model (5) of color kinetics of dried carrots

	a*				b*				ΔE*			ΔC*
			K × 10^2				K × 10^2			K × 10^2			K × 10^2
T, °C	X 0	Xe	(1/min)	R ^2	X 0	Xe	(1/min)	R ^2	Xe	(1/min)	R ^2	Xe	(1/min)	R ^2
60	46.3^a	23.1	2.29^b	0.990	50.4^b	23.1^a	2.53^b	0.999	27.2^a	1.40^a	0.954	27.6^a	1.24^a	0.926
70	39.8^a	21.2	2.01^b	0.945	40.3^a	19.3^a	1.48^a	0.985	26.6^a	1.55^a	0.996	27.3^a	1.41^a	0.987
80	41.7^a	20.4	2.44^b	0.979	54.8^b	21.1^a	3.65^b	0.977	27.2^a	1.87^b	0.930	30.2^a	1.38^a	0.935
90	42.5^a	13.6	1.57^a	0.969	49.9^b	18.8^a	3.33^b	0.977	37.8^b	1.31^a	0.975	40.2^b	1.14^a	0.969
The values with the same letters in columns did not differ significantly (p ≤ 0.05).

Figure 4 Kinetic changes of color parameters: (a) a* (redness); (b) b* (yellowness); and (c) L* (lightness) for carrot cubes during rehydration. Means ± standard error.

Figure 5 Kinetic changes of color indices: (a) ΔE* (total color difference); (b) ΔC* (total saturation difference); and (c) ΔH* (total hue difference) for carrot cubes during rehydration. Means ± standard error.

Table 3 Total carotenoids content for raw, blanched, and dried carrot samples

Sample	Total carotenoids (mg/100 g d.b.)	β-carotene (mg/100 g d.b.)
R	191.05 ± 0.27	117.29 ± 0 53
Bl	189.34 ± 0.26	116.35 ± 0.55
D60	158.70 ± 0.41	96.60 ± 0.21
D70	140.41 ± 0.42	79.29 ± 0.44
D80	134.52 ± 0.55	78.08 ± 0.20
D90	122.68 ± 0.63	66.85 ± 0.47