Optimization of Pectinase Assisted Extraction of Chironji (Buchanania Lanzan) Fruit Juice Using Response Surface Methodology and Artificial Neural Network

Figures & data

Table 1. Independent variables with their levels for rotatable central composite design

			Level
Variable	Symbol	Unit	−1.682	−1	0	+1	+1.682
Concentration of pectinase	X1	% w/w	0.01	0.03	0.06	0.08	0.1
Temperature for incubation	X2	°C	30	34	40	46	50
Time of incubation	X3	Minutes	20	40	70	100	120

Table 2. RCCD experimental design with experimental, RSM predicted, and ANN predicted results of juice yield

	Independent variables			Juice yield (%)
Run	X1	X2	X3	Experimental	RSM predicted	ANN predicted
1	0.08	34	40	65.94 ± 0.54	66.24	65.97
2	0.06	50	70	68.12 ± 0.61	68.38	68.09
3	0.08	34	100	69.2 ± 0.39	69.29	69.20
4	0.03	34	40	65.58 ± 0.58	65.22	64.84
5	0.03	46	40	65.18 ± 0.32	64.87	65.18
6	0.01	40	70	63.99 ± 0.51	64.77	64.00
7	0.03	46	100	67.9 ± 0.62	67.38	67.80
8	0.06	40	70	68.02 ± 0.29	67.97	68.17
9	0.1	40	70	68.91 ± 0.45	68.44	68.91
10	0.06	40	120	69.08 ± 0.72	69.33	69.06
11	0.06	40	20	64.58 ± 0.38	64.65	64.59
12	0.08	46	100	70.58 ± 0.32	70.72	71.27
13	0.08	46	40	66.52 ± 0.75	66.6	66.52
14	0.03	34	100	66.97 ± 0.64	66.67	66.47
15	0.06	40	70	68.84 ± 0.37	67.97	68.17
16	0.06	40	70	67.7 ± 0.41	67.97	68.17
17	0.06	30	70	67.42 ± 0.49	67.47	67.42
18	0.06	40	70	67.73 ± 0.45	67.97	68.17
19	0.06	40	70	67.59 ± 0.51	67.97	68.17
20	0.06	40	70	68 ± 0.29	67.97	68.17

X₁: Concentration of pectinase (% w/w), X₂: Temperature for incubation (°C), X₃: Time of incubation (Minutes)

Table 3. Analysis of variance (ANOVA) for the quadratic model

Source	Sum of squares	df	Mean square	F-value	p-value
Model	50.47	9	5.61	20.64	< .0001	significant
X1-Enzyme concentration	16.22	1	16.22	59.70	< .0001
X2-Temperature	0.9848	1	0.9848	3.62	.0861
X3-Time	26.43	1	26.43	97.26	< .0001
X1X2	0.2556	1	0.2556	0.9407	.3550
X1X3	1.29	1	1.29	4.74	.0545
X2X3	0.5671	1	0.5671	2.09	.1791
X1^2	3.36	1	3.36	12.36	.0056
X2^2	0.0037	1	0.0037	0.0138	.9090
X3^2	1.75	1	1.75	6.44	.0295
Residual	2.72	10	0.2717
Lack of Fit	1.68	5	0.3365	1.63	.3033	not significant
Pure Error	1.03	5	0.2069
Cor Total	53.19	19

P-values less than .05 indicate model terms are significant

Table 4. Validation of RSM and ANN-GA model

	Optimized conditions			Juice yield (%)
Methods	X1	X2	X3	Predicted	Experimental	p-value	AAD (%)
Control	-	-	-	-	53.86 ± 0.45	-	-
RSM	0.08	45.8	99.5	70.64	70.73 ± 0.37	.701	0.4
ANN-GA	0.09	48.7	118	72.68	72.52 ± 0.25	.391	0.34

Control: untreated sample, X₁: Concentration of pectinase (% w/w), X₂: Temperature for incubation (°C), X₃: Time of incubation (Minutes), P-values < .05 indicates significance, AAD: Absolute average deviation

Table 5. Physicochemical properties of the untreated juice (control) and pectinase treated juice at optimized conditions (RSM and ANN-GA)

Properties	Control	RSM optimized	ANN-GA optimized
Turbidity (NTU)	265.667 ^c ± 1.528	101.333^b ± 2.082	91.333^a ± 0.577
Viscosity (cP)	1.443^b ± 0.005	1.273^a ± 0.005	1.276^a ± 0.005
Clarity (%T)	0.633^a ± 0.058	0.766^b ± 0.057	0.966 ^c ± 0.057
pH	4.330^b ± 0.010	4.063^a ± 0.005	4.060^a ± 0
TSS (°Brix)	13.433^a ± 0.115	14.3^b ± 0.1	14.466^b ± 0.057
L*	15.146^c ± 0.040	11.573^b ± 0.032	10.243^a ± 0.015
a*	12.970^c ± 0.026	11.606^b ± 0.095	9.833^a ± 0.035
b*	5.583^b ± 0.075	4.183^a ± 0.032	4.180^a ± 0.036
∆E	-	4.073^a ± 0.026	5.988^b ± 0.094
Refractive index	1.353^a ± 0	1.354^b ± 0	1.354^b ± 0
Antioxidant activity (%)	77.665^a ± 0.906	80.250^b ± 0.803	79.710^b ± 0.816
Polyphenol (mg GAE/100 ml)	102.983^b ± 0.235	92.853^a ± 0.432	113.160 ^c ± 0.427

Values are presented in mean ± Standard deviation, Means in a row with not same superscripts are significantly different (P < .05)

Figure 1. RSM predicted vs. Experimental value of juice yield (%)

Figure 2. Influence of interaction of independent variables on juice yield (%) (a) concentration of pectinase (% w/w) and temperature for incubation (°C), (b) concentration of pectinase (% w/w) and time of incubation (minutes), (c) temperature for incubation (°C) and time of incubation (minutes)

Figure 3. ANN predicted (all data set) vs. Experimental value of juice yield (%)

Figure 4. Change in fitness value with the change in the number of generations during GA optimization