Kinetic of Color Changes in Almond (Akbadem Variety) During Roasting and Storage

Figures & data

FIGURE 1 Examples of roasted and ground Akbadem.

TABLE 1 Initial characteristics of raw almonds

Chemical and physical composition		Size and gravimetric properties
Total oil (%)	53.93 ± 1.59	Surface area (mm^2)	533.90 ± 65.86
Protein (%)	20.57 ± 0.07	Length (mm)	28.25 ± 1.92
Moisture (%)	3.57 ± 0.15	Width (mm)	14.28 ± 1.17
Total ash (%)	3.19 ± 0.01	Thickness (mm)	6.87 ± 0.53
Water activity	0.38 ± 0.03	Weight (g)	1.38 ± 0.26
L	62.96 ± 1.81
A	5.11 ± 0.93
B	16.36 ± 0.76

FIGURE 2 Kinetics of L-values of roasted almonds.

TABLE 2 L-, a-, and b-values of roasted almonds at different temperatures (150, 160, and 170°C) and times (10, 20, 30, and 40 min)

	Roasting temperature and roasting time (minute)
	150°C				160°C				170°C
	10	20	30	40	10	20	30	40	10	20	30	40
L	61.77 ± 0.54	58.21 ± 1.86	56.69 ± 0.58	52.34 ± 2.52	61.05 ± 0.55	55.77 ± 0.09	55.12 ± 1.36	47.96 ± 1.35	60.11 ± 2.24	51.94 ± 1.83	46.36 ± 0.67	43.17 ± 0.09
a	5.46 ± 0.13	6.21 ± 0.27	7.65 ± 0.06	9.52 ± 0.03	5.79 ± 0.45	7.54 ± 0.29	8.78 ± 0.24	11.96 ± 0.01	5.61 ± 0.06	9.23 ± 0.23	12.15 ± 0.15	14.25 ± 0.26
b	16.55 ± 0.35	17.87 ± 0.63	21.58 ± 0.29	24.25 ± 0.87	17.95 ± 0.33	20.62 ± 0.04	24.82 ± 0.02	28.71 ± 0.39	17.40 ± 0.10	24.28 ± 0.37	28.21 ± 0.32	29.53 ± 0.06

TABLE 3 First-order kinetic parameters for total color change of almonds during roasting with different temperatures (150, 160, and 170°C) and times (10, 20, 30, and 40 minutes)

Color parameter	Temp. (ºC)	k×10^3 (min^−^1)	Q10 (150–170°C)	Ea (Kcal mol^−^1)	R^2
L	150	4.6 ± 0.0008	1.76 ± 0,29	14.80 ± 4.26	0.99 ± 0.0075
	160	6.5 ± 0.0009
	170	10.1 ± 0.0006
∆E	150	71.7 ± 0.0008	1.13 ± 0.05	3.16 ± 1.15	0.97 ± 0.0377
	160	76.0 ± 0.0038
	170	85.1 ± 0.0066
Metric chroma (C)	150	10.9 ± 0.0004	1.42 ± 0.03	9.57 ± 0.59	0.98 ± 0.0085
	160	15.0 ± 0.0001
	170	18.1 ± 0.0002
Hue angle	150	1.3 ± 0.0003	1.90 ± 0.33	16.62 ± 4.36	0.95 ± 0.0155
	160	1.7 ± 0.0002
	170	3.2 ± 0.0003
a	150	15.8 ± 0.0001	1.49 ± 0.03	10.79 ± 0.55	0.99 ± 0.0003
	160	21.1 ± 0.0005
	170	28.2 ± 0.0007
b	150	10.5 ± 0.0008	1.38 ± 0.06	8.65 ± 1.22	0.96 ± 0.0049
	160	14.5 ± 0.0005
	170	16.6 ± 0.0003
Metric saturation (S)	150	26.8 ± 0.0022	1.46 ± 0.08	10.31 ± 1.58	0.99 ± 0.0025
	160	33.6 ± 0.0061
	170	39.9 ± 0.0113

FIGURE 3 The results of L-value kinetics of roasting time against the storage time.

TABLE 4 First-order kinetic parameters for total color change during 4 and 22°C storage periods of almonds roasted with different temperatures (150, 160, and 170°C) and times (10, 20, 30, and 40 minutes)

Storage periods (min)
		10				20
Color parameter	Storage temprature (°C)	k×10^2	Q1ₒ	Eₐ	R^2	k×10^2	Q1ₒ	Eₐ	R^2
L		1.57 ± 0.005	1.46 ± 0.057	10.32 ± 0.976	0.96 ± 0.039	1.61 ± 0.005	1.64 ± 0.074	13.20 ± 1.243	0.95 ± 0.005
∆E		33.14 ± 0.043	1.96 ± 0.015	4.94 ± 0.376	0.97 ± 0.030	40.68 ± 0.030	1.11 ± 0.018	2.77 ± 0.445	0.96 ± 0.011
Metric chroma (C)		5.80 ± 0.013	1.39 ± 0.093	8.77 ± 1.804	0.94 ± 0.010	6.32 ± 0.005	1.12 ± 0.045	3.02 ± 1.111	0.99 ± 0.013
Hue angle	4	0.31 ± 0.001	2.56 ± 1,279	20.54 ± 3.442	0.95 ± 0.045	1.00 ± 0.004	1.74 ± 0.046	14.67 ± 0.661	0.96 ± 0.029
A		4.67 ± 0.006	1.18 ± 0.039	4.65 ± 0,911	0.98 ± 0.010	4.03 ± 0.003	1.12 ± 0.297	7.06 ± 0.275	0.96 ± 0.021
B		5.87 ± 0.016	1.46 ± 0.018	10.25 ± 0.284	0.95 ± 0.020	6.78 ± 0.007	1.14 ± 0.058	4.67 ± 1.405	0.99 ± 0.058
Metric saturation (S)		9.43 ± 0.017	1.28 ± 0.110	6.61 ± 220	0.97 ± 0.034	10.94 ± 0.005	1.07 ± 0.059	2.47 ± 1.195	0.98 ± 0.021
L		2.04 ± 0.005	0.73 ± 0.017	9.08 ± 0.624	0.96 ± 0.035	1.26 ± 0.002	0.83 ± 0.074	5.32 ± 1.693	0.97 ± 0.008
∆E		37.04 ± 0.18	0.93 ± 0.008	1.89 ± 0.245	0.95 ± 0.022	65.79 ± 0.436	0.46 ± 0.031	17.95 ± 2.114	0.99 ± 0.016
Metric chroma (C)		5.43 ± 0.006	1.15 ± 0.051	3.94 ± 1.196	0.97 ± 0.036	5.94 ± 0.006	1.17 ± 0.041	4.25 ± 0.982	0.99 ± 0.18
Hue angle	22	0.6 ± 0.004	1.95 ± 0.403	17.34 ± 3.127	0.95 ± 0.033	0.61 ± 0.005	3.29 ± 0.815	29.84 ± 4.283	0.96 ± 0.010
A		3.94 ± 0.008	1.37 ± 0.189	8.37 ± 2.516	0.96 ± 0.037	4.3 ± 0.009	0.79 ± 0.144	3.89 ± 1.152	0.99 ± 0.012
B		5.69 ± 0.007	1.18 ± 0.047	4.65 ± 1.090	0.96 ± 0.027	6.18 ± 0.008	1.20 ± 0.038	5.04 ± 0.861	0.96 ± 0.032
MetricSaturation (S)		9.4 ± 0.021	1.36 ± 0.104	8.23 ± 2.043	0.96 ± 0.015	10.65 ± 0.012	1.18 ± 0.067	4.56 ± 1.551	0.97 ± 0.032
		Sorage periods (min)
		30				40
Color parameter	Storage temprature (°C)	k×10^2	Q1ₒ	Eₐ	R^2	k×10^2	Q1ₒ	Eₐ	R^2
L		2.43 ± 0.008	1.65 ± 0.076	13.4 ± 1.134	0.97 ± 0.024	2.37 ± 0.118	2.28 ± 0.324	21.28 ± 3.388	0.95 ± 0.005
∆E		44.10 ± 0.029	1.09 ± 0.008	2.3 ± 0.261	0.99 ± 0.007	72.38 ± 0.367	0.51 ± 0.010	15.85 ± 1.432	0.96 ± 0.033
Metric chroma (C)		7.57 ± 0.006	1.11 ± 0.046	2.90 ± 1.156	0.97 ± 0.017	8.03 ± 0.014	1.26 ± 0.033	6.29 ± 0.715	0.99 ± 0.010
Hue angle	4	1.13 ± 0.002	1.29 ± .195	10.38 ± 2.161	0.96 ± 0.019	1.54 ± 0.004	1.45 ± 0.157	9.92 ± 1.054	0.95 ± 0.014
A		4.56 ± 0.007	1.22 ± 0.067	5.48 ± 1.491	0.99 ± 0.017	4.46 ± 0.010	1.34 ± 0.037	7.86 ± 0.715	0.95 ± 0.037
B		8.23 ± 0.009	1.15 ± 0.020	3.84 ± 0.495	0.98 ± 0.020	8.83 ± 0.017	1.49 ± 0.044	7.07 ± 0.902	0.98 ± 0.029
Metric saturation (S)		12.84 ± 0.010	1.11 ± 0.011	2.81 ± 0.282	0.96 ± 0.023	21.38 ± 0.119	2.10 ± 0.065	19.41 ± 0.615	0.95 ± 0.028
L		2.25 ± 0.005	0.75 ± 0.137	5.55 ± 1.085	0.98 ± 0.023	1.34 ± 0.002	1.23 ± 0.199	7.83 ± 1.319	0.96 ± 0.028
∆E		40.97 ± 0.045	1.17 ± 0.089	3.45 ± 1.781	0.96 ± 0.038	41.62 ± 0.036	1.13 ± 0.018	3.27 ± 0.459	0.97 ± 0.026
Metric chroma (C)		6.52 ± 0.006	1.14 ± 0.083	3.61 ± 2.000	0.98 ± 0.031	7.22 ± 0.007	1.14 ± 0.045	3.68 ± 1.077	0.98 ± 0.017
Hue angle	22	1.04 ± 0.004	1.87 ± 0.257	16.56 ± 2.454	0.99 ± 0.010	1.37 ± 0.005	1.76 ± 0.109	15.23 ± 1.658	0.99 ± 0.014
A		3.65 ± 0.002	0.94 ± 0.034	1.63 ± 1.007	0.95 ± 0.034	4.17 ± 0.004	0.88 ± 0.030	3.67 ± 0.916	0.94 ± 0.041
B		7.08 ± 0.009	1.19 ± 0.096	4.69 ± 2.218	0.98 ± 0.019	8.02 ± 0.010	1.19 ± 0.033	6.21 ± 2.262	0.95 ± 0.048
Metric saturation (S)		11.11 ± 0.017	1.25 ± 0.189	5.82 ± 2.936	0.95 ± 0.028	21.63 ± .132	2.24 ± 0.192	20.89 ± 2.143	0.97 ± 0.009

*Kinetic modeling was carried out almond samples stored in 6 months. L, a, and b color values was measured at 2, 4, and 6 months. k: min⁻¹; Ea: (Kcal/mol).