Studies on the Optimization and Stability of Low-Fat Biscuit Using Carbohydrate-Based Fat Replacers

Figures & data

TABLE 1 Experimental variables for biscuits, their coded and uncoded (actual) values

	Coded form				Uncoded form
					X1	X2			X3	X4
Expt. No.	X1	X2	X3	X4	Sugar*	Fat*	PD*	GG*	A.B.*	Water*
First order part
1	−1	−1	−1	−1	27	21	13.8	0.2	1	21
2	+1	−1	−1	−1	33	21	13.8	0.2	1	21
3	−1	+1	−1	−1	27	14	20.6	0.4	1	21
4	+1	+1	−1	−1	33	14	20.6	0.4	1	21
5	−1	−1	+1	−1	27	21	13.8	0.2	2	21
6	+1	−1	+1	−1	33	21	13.8	0.2	2	21
7	−1	+1	+1	−1	27	14	20.6	0.4	2	21
8	+1	+1	+1	−1	33	14	20.6	0.4	2	21
9	−1	−1	−1	+1	27	21	13.8	0.2	1	23
10	+1	−1	−1	+1	33	21	13.8	0.2	1	23
11	−1	+1	−1	+1	27	14	20.6	0.4	1	23
12	+1	+1	−1	+1	33	14	20.6	0.4	1	23
13	−1	−1	+1	+1	27	21	13.8	0.2	2	23
14	+1	−1	+1	+1	33	21	13.8	0.2	2	23
15	−1	+1	+1	+1	27	14	20.6	0.4	2	23
16	+1	+1	+1	+1	33	14	20.6	0.4	2	23
Second order part
17	−α	0	0	0	24	17.5	17.2	0.3	1.5	22
18	+ α	0	0	0	36	17.5	17.2	0.3	1.5	22
19	0	−α	0	0	30	24.5	10.4	0.1	1.5	22
20	0	+ α	0	0	30	10.5	24	0.5	1.5	22
21	0	0	−α	0	30	17.5	17.2	0.3	0.5	22
22	0	0	+ α	0	30	17.5	17.2	0.3	2.5	22
23	0	0	0	−α	30	17.5	17.2	0.3	1.5	20
24	0	0	0	+ α	30	17.5	17.2	0.3	1.5	24
Center point
25	0	0	0	0	30	17.5	17.2	0.3	1.5	22
26	0	0	0	0	30	17.5	17.2	0.3	1.5	22
27	0	0	0	0	30	17.5	17.2	0.3	1.5	22
28	0	0	0	0	30	17.5	17.2	0.3	1.5	22
29	0	0	0	0	30	17.5	17.2	0.3	1.5	22
30	0	0	0	0	30	17.5	17.2	0.3	1.5	22
31	0	0	0	0	30	17.5	17.2	0.3	1.5	22
32	0	0	0	0	30	17.5	17.2	0.3	1.5	22

*g/100 g flour;

PD: Polydextrose; GG: Guar gum; A.B.: Ammonium bicarbonate.

TABLE 2 Regression coefficients of full second order model and significant terms for different properties of low-fat soft dough biscuits containing polydextrose and guar gum

Factor	Spread ratio	Hardness	Stress-strain ratio	Overall acceptability
Intercept	10.977	32.005	0.939	3.259
X1	0.254***	−1.071	−0.121**	−0.160***
X2	0.064	4.048***	−0.012	−0.249***
X3	0.384***	−5.084***	−0.186***	−0.207***
X4	−0.150*	−2.234*	−0.104**	0.102*
X1 X2	−0.147	−0.782	−0.095	0.138*
X1 X3	−0.014	−0.486	−0.071	0.141**
X1 X4	0.033	1.228	−0.000	−0.079
X2 X3	−0.069	0.371	0.076	0.019
X2 X4	−0.197*	1.765	0.118*	−0.001
X3 X4	0.153	0.557	0.093	0.039
X1^2	0.204**	0.505	0.034	0.056
X2^2	0.005	2.114*	0.013	−0.001
X3^2	0.137*	2.479**	0.063	0.087*
X4^2	0.165**	1.957*	0.010	0.123**
R^2	76.44	73.63	70.53	79.93
F-value	3.94***	3.39***	2.91**	4.83***
Adequate precision	7.34	6.59	7.13	10.03

Significant at ***1%; **5%; *10%;

X₁: Sugar; X₂: Composite fat; X₃: Ammonium bicarbonate; X₄: Water;

X₁, X₂, X₃, and X₄ are in coded form.

FIGURE 1 Contour plot representing the effect of different variables on quality of biscuits (X₁: sugar; X₂: composite fat; X₃: ammonium bicarbonate; X₄: water).

TABLE 3 Physical characteristics of different types of biscuits*

Products	Diameter (cm)	Thickness (cm)	Spread ratio	Hardness (N)	Stress-strain ratio
A	5.98 ± 0.01^a	0.62 ± 0.00^a	9.64 ± 0.01^a	32.52 ± 1.53^a	0.73 ± 0.08^a
B	6.51 ± 0.01^b	0.58 ± 0.004^b	11.25 ± 0.07^b	48.44 ± 3.21^b	1.74 ± 0.78^b

*Average of six determinations;

Figures followed by different letters in the same column are significantly different from each other (p < 0.05);

A: Control biscuits;

B: Low-fat biscuit containing carbohydrate based fat replacers (polydextrose and guar gum).

TABLE 4 Chemical characteristics of different types of biscuits*

Products	Moisture (%)	Crude protein (%)	Crude fat (%)	Total ash (%)	Crude fiber (%)	Carbohydrates (by difference) (%)	Calorific value (kcal/100 g)
A	5.21 ± 0.06^a	7.57 ± 0.24^a	21.47 ± 0.2^a	0.99 ± 0.00^a	0.57 ± 0.03^a	64.19 ± 0.41^a	480.28 ± 0.83^a
		(7.99)	(22.65)	(1.04)	(0.60)	(67.72)	(506.68)
B	7.20 ± 0.12^b	7.49 ± 0.03^b	6.45 ± 0.05^b	1.00 ± 0.00^b	0.68 ± 0.02^b	77.18 ± 0.06^b	396.72 ± 0.33^b
		(8.07)	(6.95)	(1.07)	(0.74)	(83.16)	(427.5)

Values given in parenthesis are on dry weight basis;

*Average of six determinations;

Figures followed by different letters in the same column are significantly different from each other (p < 0.05);

A: Control biscuits;

B: Low-fat biscuit containing carbohydrate based fat replacers (polydextrose and guar gum).

TABLE 5 Changes in moisture content (%) of biscuits during storage*

	Storage period (days)
Products	0	15	30	45	60	75	90	SEM	CD at 5%
A	5.21 ± 0.06	5.22 ± 0.02	5.26 ± 0.02	5.26 ± 0.03	5.31 ± 0.00	5.34 ± 0.03	5.36 ± 0.03	0.01	0.05
B	7.20 ± 0.12	7.21 ± 0.04	7.23 ± 0.02	7.24 ± 0.03	7.24 ± 0.01	7.25 ± 0.03	7.25 ± 0.14	0.03	0.09

*Average of three determinations;

A: Control biscuits;

B: Low-fat biscuit containing carbohydrate based fat replacers (polydextrose and guar gum).

FIGURE 2 Changes in peroxide value (meq of O₂/kg of fat) of biscuits during storage.

FIGURE 3 Changes in free-fatty acid content (%) of biscuits during storage.

TABLE 6 Changes in hardness (N) of biscuits during storage*

	Storage period (in months)
Products	0	1	2	3	SEM	CD at 5%
A	32.52 ± 1.54	31.44 ± 0.69	31.19 ± 0.91	28.74 ± 1.29	0.47	1.39
B	48.44 ± 3.20	45.24 ± 1.31	40.89 ± 1.51	38.21 ± 0.71	0.84	2.47

*Average of three determinations;

A: Control biscuits;

B: Low-fat biscuit containing carbohydrate based fat replacers (polydextrose and guar gum).

FIGURE 4 Changes in taste scores of optimized products during storage.

FIGURE 5 Changes in flavor scores of optimized products during storage.

FIGURE 6 Changes in overall acceptability (OAA) scores of biscuits during storage.