Impact of Osmotic Distillation on the Sensory Properties and Quality of Low Alcohol Beer
Table 4
Volatile compounds concentration, loss percentage, physical and chemical properties, flavour unit (FU) in original (OB), and low alcohol beer samples (LAB, LAB+).
Compounds
OB
LAB
Loss (%)
LAB+
Loss (%)
MW (g/mol)
Bp (°C)
Vp (hPa)
Ft (mg/L)
Fb
FU OB
FU LAB
FU LAB+
n-Propanol
79
78
60.1
97
19.3
800
Alcohol
0.02
0.00
0.00
Isobutanol
70
70
74.12
108
8.0
200
Alcohol
0.10
0.03
0.03
Amyl alcohols
66
66
88.15
102
3.0
70
Alcohol, banana, sweetish, aromatic
0.77
0.26
0.26
Furfuryl alcohol
34
35
98.1
170
0.7
3000
Sugar Cane, Wood
0.00
0.00
0.00
2-Phenylethanol
39
41
122.16
219
0.11
125
Roses, sweetish, aromatic
0.20
0.12
0.12
Sum of alcohols (mg/L)
61
62
Ethyl acetate
79
78
88.11
76
97.3
33
Solvent, fruity, sweetish
0.13
0.03
0.03
Ethyl butanoate
85
85
116.16
120
17.0
0.4
Papaya, butter, apple
0.08
0.01
0.01
Isoamyl acetate
86
86
130.18
142
7.5
1.6
Banana, apple, solvent
0.08
0.01
0.01
Ethyl hexanoate
73
70
144.21
168
1.44
0.23
Apple, fruity, aniseed
0.33
0.09
0.10
Ethyl octanoate
56
53
172.26
206
0.15
0.9
Apple, sweetish, fruity
0.09
0.04
0.04
Sum of esters (mg/L)
78
78
Acetaldehyde
42
9
44.05
21
1009
25
Green apple, fruity
0.29
0.17
0.26
2-Methylbutanal
53
−8
86.13
90
48
1.25
Green grass, fruity, sour, medicinal
0.02
0.01
0.02
3-Methylbutanal
54
8
88.15
130
40
0.6
Unripe banana, apple, cherry, cheese
0.14
0.07
0.13
Hexanal
−56
−463
100.16
130
13
0.35
Bitter, astringent, green leaves
0.00
0.00
0.02
Furfuraldehyde
−9
±
−95
96.08
162
2.3
150
Paper, husk
0.00
0.00
0.00
3-Methylpropionaldehyde
−1
−54
58.08
46
0.53
0.25
Mashed potato, warm, soup-like
0.12
0.13
0.19
2-Phenylacetaldehyde
−19
−71
120.15
195
0.52
1.6
Hyacinth, lilac, aldehyde
0.02
0.02
0.03
Sum of aldehydes (μg/L)
41
8
Diacetyl
−131
−454
86.1
88
69.59
0.15
Butter, scotch
0.03
0.06
0.14
2,3-Pentanedione
100.12
110
28.53
0.9
Diacetyl, fruity
0.00
0.00
0.00
Sum of ketones (μg/L)
−131
−558
MW, molecular weight; Bp, boiling point; Vp, vapour pressure; Ft, flavour threshold; FB, flavour in beer, FU, flavour unit; data represent the mean of 2 replicates ± SD. Different letters correspond to statistically significant differences among original beer (OB) and low alcohol beer (LAB) and low alcohol beer added with hop extract and pectin solution (LAB+) according to one-way ANOVA followed by -test ().
