Skip to main content

Table 6 Volatile compounds in soymilk before and after enzyme treatment

From: A statistical strategy for optimizing the production of α-galactosidase by a newly isolated Aspergillus niger NRC114 and assessing its efficacy in improving soymilk properties

Volatile compound KRIa Soymilk b Descriptionc
Control Enzyme treatment
Aldehydes
 2-Methylbutanal 914 2.08 4.22  
 3-Methylbutanal 918 0.45 1.12 Dark chocolate
 Pentanal 975 0.59 1.33 Grass, green
 Hexanal 1074 10.53 2.86  
 Heptanal 1183 5.24 2.36 Rancid
 Octanal 1282 4.35 2.43 Lemon, fruity
 Nonanal 1387 5.87 4.87 Floral, citrus
 Benzaldehyde 1513 5.14 0.84 Almond
Subtotal   34.25 20.03  
Alcohols
 Ethanol 931 0.48 4.69  
 2-Butanol 1025 1.09 3.63  
 2-Methyl-1-propanol 1088 2.53 1.35  
 3-Pentanol 1102 0.13 1.13  
 1-Butanol 1143 0.02 0.98  
 1-Penten-3-ol 1157 0.21 2.96  
 3-Methyl-1-butanol 1203 0.17 0.84  
 1-Hexanol 1352 0.98 0.23  
Subtotal   4.63 15.58  
Esters
 Ethyl butanoate 1031 0.95 3.02  
 Ethyl 2-methylbutanoate 1049 0.67 3.11  
 Ethyl 3-methylbutanoate 1061 0.49 2.86  
 Ethyl hexanoate 1224 1.05 1.21  
 Ethyl lactate 1327 0.95 1.50  
 Ethyl hexadecanoate 2205 0.41 1.03  
Subtotal   4.52 12.73  
Acids
 Acetic acid 1415 33.73 1.03 Sour
 Propanoic acid 1513 4.51 1.94  
 2-Methyl-propanoic acid 1538 1.48 0.89  
 Butanoic acid 1597 3.38 1.27  
 Pentanoic acid 1714 0.62 1.68  
 Hexanoic acid 1822 1.32 1.01  
Subtotal   45.04 7.82  
Ketones
 2-Butanone 906 0.19 1.56  
 2-Pentanone 973 2.14 0.90  
 2-Hexanone 1072 0.50 1.34  
 (E)-3-Penten-2-one 1116 0.14 1.73  
Subtotal   2.97 5.53  
Furans and furan derivatives
 2-Methylfuran 873 4.03 3.78  
 2-Ethylfuran 954 1.15 0.7 Burnt
 2-Butylfuran 1128 0.60 1.78  
 2-Pentylfuran 1225 0.15 1.46  
 Furfural 1457 0.86 11.60  
 2-Furanmethanol 1654 0.35 7.02  
Subtotal   7.14 26.34  
Sulfur-containing compounds
 4-Methylthiazole 1625 0.19 0.25  
 2-Acetylthiazole 1636 0.13 0.71  
 3-(Methylthio)-1-propanol 1704 0.11 10.48  
Subtotal   0.43 11.44  
  1. aKovats retention index
  2. bvalues are expressed as relative area percentages
  3. ccited from Lv et al. [37]