Prediction of the Mould-Free Shelf Life of Muffins

Figures & data

Table 1 Composition ^a of cake samples in experimental design.

Ingredient	1^st	2^nd	3^rd	4^th	5^th ^c	Control
Flour	80	80	80	80	80	80
Starch	20	20	20	20	20	20
Water	75	75	75	75	75	75
Baking powder	3	3	3	3	3	3
Sunflower oil	33	33	33	33	33	33
Emulsifier	1	1	1	1	1	1
Eggs	30	30	30	30	30	30
Milk	12	12	12	12	12	12
Salt	1.5	1.5	1.5	variable	variable	1.5
Sugar	variable	variable	variable	variable	variable	75
Glycerol	variable	variable	variable	variable	variable
Potassium Sorbate	variable	variable	variable	variable	variable
Citric acid	variable	0	0	variable	variable
Sodium diacetate	0	variable	0	0	0
Tartaric acid	0		variable	0	0
Ethanol ^b	0	0	0	variable	variable
^ag/100 g of (flour + starch); ^bg/100 g of muffin; ^cmuffin samples were pasteurized.

Table 2 Coded and natural values of design factors.

	Design factors	Coded (−1,0, + 1) and natural levels ^a
Symbol	Ingredient	−1	0	+1	Jj
	Sugar	60.0	90.0	120.0	30.00
	Glycerol 1,2,3 design	1.0	4.00	7.0	3.00
	4,5 design	0.5	1.25	2.0	0.75
	Potassium sorbate	0.1	0.55	1.0	0.45
	Citric acid	0.1	0.55	1.0	0.45
	Sodium diacetate	0.1	0.55	1.0	0.45
	Tartaric acid	0.1	0.55	1.0	0.45
	Salt	1.0	4.00	7.0	3.00
	Ethanol ^b	0.5	1.00	1.5	0.50
^ag/100 g of (flour + starch); ^bg/100 g of muffin.

Table 3 Shelf life of muffin with citric acid as acidic agent (first design).

Trial no.	x1 Sugar ^a	x2 Glycerol ^a	x3 K Sorbate ^a	x4 Citric acid ^a	Shelf life ^b (days)	Relative shelf life ^c (y1)
Control	75	0	0	0	7.3	1.00
1	120	7	1.0	1.0	31.8	4.36
2	120	7	1.0	0.1	26.8	3.67
3	120	7	0.1	0.1	13.1	1.79
4	120	1	0.1	0.1	12.7	1.74
5	120	7	0.1	1.0	20.0	2.74
6	120	1	0.1	1.0	18.4	2.52
7	120	1	1.0	1.0	19.3	2.64
8	120	1	1.0	0.1	17.7	2.42
9	60	7	1.0	1.0	14.4	1.97
10	60	1	1.0	1.0	10.7	1.47
11	60	1	0.1	1.0	9.3	1.27
12	60	1	0.1	0.1	8.2	1.12
13	60	1	1.0	0.1	10.2	1.40
14	60	7	0.1	1.0	10.6	1.45
15	60	7	0.1	0.1	8.7	1.19
16	60	7	1.0	0.1	10.4	1.42
Basic level	90	4	0.55	0.55	14.6	2.00
^a Natural values of factors (g/100 g flour + starch); ^b Mean, ± SD was in the range 0.5–1; ^c ± SD was in the range 0.08 – 0.18.

Table 4 Shelf life of muffin with sodium diacetate as acidic agent (second design)

Trial no.	x1 Sugar ^a	x2 Glycerol ^a	x3 K Sorbate ^a	x4 Na diacetate ^a	Shelf life ^b (days)	Relative shelf life ^c (y1)
Control	75	0	0	0	8.2	1.00
1	120	7	1.0	1.0	33.8	4.12
2	120	7	1.0	0.1	27.7	3.38
3	120	7	0.1	0.1	14.4	1.76
4	120	1	0.1	0.1	13.9	1.70
5	120	7	0.1	1.0	18.4	2.24
6	120	1	0.1	1.0	16.9	2.06
7	120	1	1.0	1.0	19.9	2.43
8	120	1	1.0	0.1	18.1	2.21
9	60	7	1.0	1.0	16.0	1.95
10	60	1	1.0	1.0	11.4	1.39
11	60	1	0.1	1.0	10.0	1.22
12	60	1	0.1	0.1	7.9	0.96
13	60	1	1.0	0.1	11.4	1.39
14	60	7	0.1	1.0	11.7	1.43
15	60	7	0.1	0.1	8.0	0.98
16	60	7	1.0	0.1	11.6	1.41
Basic level	90	4	0.55	0.55	15.6	1.90
^a Natural values of factors (g/100 g flour + starch); ^b Mean, ± SD was in the range 0.5–1.1; ^c ± SD was in the range 0.08–0.19.

Table 5 Shelf life of muffin with tartaric acid as acidic agent (third design).

Trial no.	x1 Sugar ^a	x2 Glycerol ^a	x3 K Sorbate ^a	x5 Tartaric acid ^a	Shelf life ^b (days)	Relative shelf life ^c (y1)
Control	75	0	0	0	8.3	1.00
1	120	7	1.0	1.0	33.6	4.05
2	120	7	1.0	0.1	26.0	3.13
3	120	7	0.1	0.1	14.5	1.75
4	120	1	0.1	0.1	14.0	1.69
5	120	7	0.1	1.0	19.2	2.31
6	120	1	0.1	1.0	16.4	1.98
7	120	1	1.0	1.0	20.3	2.45
8	120	1	1.0	0.1	18.6	2.24
9	60	7	1.0	1.0	15.6	1.88
10	60	1	1.0	1.0	11.3	1.36
11	60	1	0.1	1.0	10.3	1.24
12	60	1	0.1	0.1	8.1	0.98
13	60	1	1.0	0.1	11.5	1.39
14	60	7	0.1	1.0	11.9	1.43
15	60	7	0.1	0.1	8.5	1.02
16	60	7	1.0	0.1	11.6	1.40
Basic level	90	4	0.55	0.55	15.2	1.83
^aNatural values of factors (g/100 g flour + starch); ^bMean, ± SD was in the range 0.5–1.1; ^c± SD was in the range 0.08 – 0.20.

Table 6 Shelf life of muffin with citric acid and ethanol (fourth design).

Trial no.	x1 Sugar ^a	x2 Glycerol ^a	x3 K Sorbate ^a	x4 Citric acid ^a	x7 Salt ^a	x8 Ethanol ^b	Shelf life ^c (days)	Relative shelf life (y1)
Control	75	0	0	0	1.5	0	8.5	1.0
49	60	2.0	1.0	1.0	7	0.5	>50	>5.88
50	60	2.0	1.0	1.0	1	0.5	>50	>5.88
51	60	2.0	0.1	1.0	7	0.5	22	2.6
52	60	2.0	1.0	0.1	7	0.5	>50	>5.88
53	60	0.5	1.0	1.0	7	0.5	>50	>5.88
54	60	2.0	0.1	1.0	1	0.5	16	1.9
55	60	2.0	1.0	0.1	1	0.5	>50	>5.88
56	60	0.5	1.0	1.0	1	0.5	>30	>3.53
57	60	2.0	0.1	0.1	7	0.5	21	2.47
58	60	0.5	0.1	1.0	7	0.5	14	1.65
59	60	0.5	1.0	0.1	7	0.5	>50	>5.88
60	60	2.0	0.1	0.1	1	0.5	15	1.76
61	60	0.5	1.0	0.1	1	0.5	30	3.53
62	60	0.5	0.1	1.0	1	0.5	10.2	1.20
63	60	0.5	0.1	0.1	7	0.5	11.0	1.29
64	60	0.5	0.1	0.1	1	0.5	9.0	1.06
Basic level	90	1.25	0.55	0.55	4	1.0	>80	>9.41
^aNatural values of factors (g/100 g flour + starch); ^bg/100 g of muffin; ^cMean.

Figure 1 Effect of acidic agent on the relative shelf life of muffin (sugar, glycerol, and K sorbate fixed at their maximum levels 120 g, 7 g, and 0.55 g, respectively, by 100 g of flour and starch).

Figure 2 Dependence of the relative shelf life of muffin (contour lines) on citric acid and potassium sorbate contents with sugar and glycerol fixed at their basic levels (90 g and 4 g, respectively, by 100 g flour and starch). Control shelf life 7.3 days. Coded values 1 to + 1 correspond to 0.1 to 1 g/100 g of flour and starch.

Figure 3 Dependence of the relative shelf life of muffin (contour lines) on Na diacetate and potassium sorbate contents with sugar and glycerol fixed at their basic levels (90 g and 4 g, respectively, by 100 g of flour and starch). Control shelf life 7.3 days. Coded values 1 to + 1 correspond to 0.1 to 1 g/100 g of flour and starch.

Figure 4 Dependence of the relative shelf life of muffin (contour lines) on tartaric acid and potassium sorbate contents with sugar and glycerol fixed at their basic levels (90 g and 4 g, respectively, by 100 g flour and starch). Control shelf life 8.3 days. Coded values 1 to + 1 correspond to 0.1 to 1 g/100 g of flour and starch.

Figure 5 Shelf life of muffins containing potassium sorbate as preservative with different methods.

Figure 6 Effect of acidic agent on the pH of muffin (sugar, glycerol, and K sorbate fixed at their basic levels 90 g, 4 g, and 0.55 g, respectively, by 100 g flour and starch).