Thermal kinetics of physical and sensory changes in baby carrot under pasteurization conditions

Figures & data

Table 1. Experimental conditions

Temperature (°C)	Heating time (min)
65	1	3	5	7	10	13	23	33	48	63
70	1	3	5	7	11	19	27	35	43
75	1	2	4	7	10	12	14	16	18	20
80	1	3	5	6	9	12	15	18
85	1	2	4	5	6	7	9	11	13
90	1	2	3	4	5	7	9	12

Figure 1. Carrot color degradation (L*, a* and b* parameters) during pasteurization process at different temperatures (65°C (○), 70°C (*), 75°C (◊), 80°C (∆), 85°C (□), 90°C (×)) (N = 3) .

Table 2. Kinetic parameters at different temperatures as zero-order and second-order models for L*, a*, b*, ∆E, firmness and energy for carrot treated under pasteurization conditions

Color parameters	Temperature	k (min^−1)	R^2	Ea (KJ/mol)
L*^b	65	0.0001	0.85	106.43
	70	0.0001	0.99
	75	0.0001	0.98
	80	0.0001	0.97
	85	0.001	0.96
	90	0.001	0.98
a*^a	65	0.275	0.81	82.02
	70	0.208	0.91
	75	0.599	0.97
	80	0.598	0.99
	85	1.211	0.96
	90	1.600	0.97
b*^b	65	0.0001	0.80	106.43
	70	0.0001	0.98
	75	0.0001	0.95
	80	0.0001	0.98
	85	0.001	0.94
	90	0.001	0.99
∆E*^a	65	0.347	0.79	92.31
	70	0.546	0.96
	75	1.304	0.99
	80	1.455	0.99
	85	2.665	0.96
	90	3.075	0.97
Firmness(N) ^b	65	0.0002	0.93	110.08
	70	0.0003	0.90
	75	0.0008	0.88
	80	0.0009	0.89
	85	0.0019	0.97
	90	0.0028	0.89
Energy (J) ^b	65	0.0001	0.87	73.54
	70	0.0002	0.96
	75	0.0003	0.97
	80	0.0004	0.99
	85	0.0006	0.96
	90	0.0006	0.98

a: Zero-order, b: Second-order

Figure 2. Pasteurization temperature (65°C (○), 70°C (*), 75°C (◊), 80°C (∆), 85°C (□), 90°C (×)) and time effects on carrot texture (firmness and energy) parameters (N = 3) .

Figure 3. FESEM graphs of non-heated and heated (1, 2, 3, 4) carrot samples, (a) Control, (b) 70°C for 43 min, (c) 80°C for 18 min and (d) 90°C for 12 min.

Table 3. Effect of pasteurization temperature and time effects on carrot sensory attributes (N = 3)

Temperature (^°C)	65°C	70°C	75°C	80°C	85°C	90°C
Time (min)	63	43	43	18	20	12
Color	2.80^bc±0.06	2.80^bc±0.06	3.00^b ±0.04	2.80^bc ±0.04	3.00^b±0.02	3.70^a±0.05
Appearance	2.82^bc ±0.03	2.82^bc ±0.03	2.20^c ±0.02	2.20^c±0.02	2.96^b ±0.06	3.96^a ±0.06
Texture	2.56^bc ±0.04	2.56^bc ±0.04	3.00^b ±0.02	2.31^d ±0.02	2.45^c ±0.04	3.45^a ±0.04
Flavor	2.96^bc ±0.04	2.88^c ±0.04	2.30^d ±0.02	3.20^b ±0.02	2.80^c ±0.04	3.45^a ±0.04
Overall acceptance	2.80^d±0.07	2.60^c±0.02	3.00^b±0.03	2.80^bc±0.03	2.80^bc±0.03	3.80^a±0.03

a, b and c: represents significant difference between different temperatures within the same attribute