Volatile compounds produced by Bacillus species alkaline fermentation of bambara groundnut (Vigna subterranean (L.) Verdc) into a dawadawa-type African food condiment using headspace solid-phase microextraction and GC × GC–TOFMS

Figures & data

Table 1. Volatile compounds in the headspace of dawadawa-type condiment produced from Bacillus fermented bambara groundnut using GC × GC–TOFMS.

			Mean concentration (µg kg^−1 of product by dried weight basis) n = 2
	Compounds	RIexp*	SFBA3^†	PALB7	OALB2	SFBA2
	Aldehydes (12)
1	Butanal, 3-methyl-	<800	15^b¶ ± 4	14^b ± 2	49^a ± 29	38^a ± 14
2	Hexanal	<800	41^a ± 1	54^a ± 21	53^a ± 49	38.6^a ± 0.8
3	3-Furaldehyde	<800	27^a ± 2	2.2^b ± 0.2	54^a ± 70	6.2^b ± 0.2
4	Heptanal	<800	30^a ± 14	3.2^b ± 0.4	3^b ± 2	3.40^b ± 0.08
5	2-Heptenal, (Z)-	871	2.8^a ± 0.8	ND	ND	ND
6	2-Heptenal, (E)-	873	ND	0.8^a ± 0.3	ND	ND
7	Benzaldehyde	878	1206^ab ± 178	2711^a ± 312	1013^b ± 333	1783^ab ± 219
8	Octanal	945	5^a ± 1	5^a ± 1	4^a ± 3	5.7^a ± 0.7
9	Benzeneacetaldehyde	1009	8^a ± 4	0.8^b ± 0.5	2.1^ab ± 0.3	3.5^ab ± 0.8
10	Benzaldehyde, 2-hydroxy-	1014	ND	ND	ND	6^a ± 2
11	Nonanal	1096	16^a ± 6	17.5^a ± 0.6	16^a ± 9	22^a ± 2
12	Decanal	1237	1.4^a ± 0.7	3.4^a ± 0.6	4^a ± 3	5.19^a ± 0.03
	Total		1352.20	2811.90	1198.10	1911.59
	Acids (16)
13	Methyl isobutyrate	<800	8^a ± 5	ND	ND	ND
14	Acetic acid	<800	658^a ± 264	ND	11^b ± 14	ND
15	Propanoic acid	<800	52^a ± 7	ND	ND	ND
16	Methyl isovalerate	<800	67^a ± 5	ND	ND	ND
17	Propanoic acid, 2-methyl-	<800	607^a ± 41	32^b ± 4	23^b ± 4	15^b ± 8
18	Butanoic acid	<800	14^a ± 7	ND	ND	ND
19	Butanoic acid, 3-methyl-	<800	1653^a ± 299	42^b ± 13	192^b ± 56	15^b ± 6
20	Butanoic acid, 2-methyl-	806	1649^a ± 355	23^ab ± 4	39^ab ± 4	11^b ± 2
21	4-Methyl-2-oxovaleric acid	849	8.2^a ± 0.3	ND	ND	ND
22	l-Lactic acid	899	ND	ND	6.2^a ± 0.2	ND
23	Isobutyl isovalerate	950	0.5^a ± 0.2	ND	ND	ND
24	Acetic acid, anhydride	1175	247^a ± 263	ND	211^a ± 34	ND
25	Isobornyl formate	1343	ND	0.9^a ± 0.3	1^a ± 1	0.6^a ± 0.1
26	4-tert-Butylcyclohexyl acetate	1345	ND	1.1^a ± 0.1	ND	1.1^ab ± 0.3
27	Pentanoic acid	1933	0.9^a ± 0.7	ND	ND	ND
28	Acetic acid, methoxy-	1940	5^a ± 5	ND	120^b ± 169	ND
	Total		4969.60	99.00	603.20	42.70
	Ketones (20)
29	2,3-Dihydroindole-2-one, 5-methoxy-1,3-dimethyl-3-(dimethylamino) methyl	<800	ND	ND	ND	50^a ± 14
30	2-Butanone	<800	1.4^a ± 0.1	ND	ND	7.9^a ± 0.7
31	Acetoin	<800	121^b ± 37	ND	875^a ± 88	ND
32	2-Pentanone, 4-hydroxy-4-methyl-	<800	11^a ± 5	1.6^b ± 0.8	ND	1.4^b ± 0.8
33	2-Heptanone	<800	ND	1.3^a ± 0.4	ND	ND
34	3-(Methylthio)-2-butanone	<800	ND	ND	0.7^a ± 0.5	0.07^b ± 0.02
35	Butyrolactone	820	0.35^a ± 0.08	ND	ND	ND
36	2-Heptanone, 4-methyl-	840	0.5^a ± 0.3	ND	ND	0.12^b ± 0.02
37	2(3H)-Furanone, dihydro-3-methyl-	873	0.3^a ± 0.1	ND	ND	ND
38	5-Hepten-2-one, 6-methyl-	916	2.8^a ± 0.3	2.4^a ± 0.2	1.9^a ± 0.1	3^a ± 1
39	3-Octanone	919	0.6^a ± 0.2	ND	1^a ± 1	ND
40	2-Octanone	926	4 ^a ± 4	ND	0.7^a ± 0.7	ND
41	2(3H)-Furanone, 5-ethyldihydro-	1029	5.98^a ± 0.01	ND	ND	ND
42	Acetophenone	1041	2.8^a ± 0.4	3.4^a ± 0.1	3.5^a ± 0.1	4.0^a ± 0.2
43	2-Nonanone	1079	ND	ND	ND	0.6^a ± 0.0
44	Bicyclo[2.2.1]heptan-2-one, 1,7,7-trimethyl-, (1S)-	1158	4.4^ab ± 0.5	4.1^ab ± 0.4	6 ^a ± 2	3.2^b ± 0.4
45	2-Decanone	1175	ND	1.1^a ± 0.2	ND	1.9^a ± 0.9
46	1,2-Propanedione, 1-phenyl-	1185	0.52^a ± 0.06	ND	ND	ND
47	2-Dodecanone	1347	0.20^a ± 0.07	ND	ND	0.50^a ± 0.04
48	2-Tridecanone	1427	ND	ND	ND	0.3^a ± 0.1
	Total		155.85	13.90	888.80	72.99
	Esters (17)
49	Propanoic acid, ethyl ester	<800	8^a ± 10	ND	ND	ND
50	Propanoic acid, 2-methyl-, ethyl ester	<800	25^a ± 2	ND	ND	ND
51	Butanoic acid, 2-methyl-, ethyl ester	<800	36.8^a ± 0.8	2.3^b ± 0.8	ND	1.2^b ± 0.5
52	Butanoic acid, 3-methyl-, ethyl ester	<800	75^a ± 4	0.9^b ± 0.8	ND	2.2^ab ± 0.5
53	Butanoic acid, 2-methyl-, propyl ester	854	0.5^a ± 0.2	ND	ND	ND
54	Butanoic acid, 3-methyl-, propyl ester	861	0.41^a ± 0.08	ND	ND	ND
55	Pentanoic acid, 4-methyl-, ethyl ester	885	1.1^a ± 0.4	ND	ND	ND
56	Pentanoic acid, 4-methyl-, methyl ester	935	1.14^a ± 0.03	ND	ND	ND
57	Butanoic acid, 2-methyl, 2-methylpropyl ester	945	0.94^a ± 0.08	ND	ND	ND
58	Propanoic acid, 2-methyl, 3-methylbutyl ester	959	6.9^a ± 2.3	ND	ND	ND
59	Butanoic acid, 2-methyl-, 3-methylbutyl ester	1088	3.82^a ± 0.01	ND	ND	0.26^b ± 0.01
60	Butanoic acid, 3-methyl-, 3-methylbutyl ester	1099	2.0^a ± 0.4	ND	ND	ND
61	Acetic acid, phenyl methyl ester	1180	2.07^a ± 0.07	ND	ND	ND
62	Propanoic acid, 2-methyl-, phenylmethyl ester	1353	2.09^a ± 0.09	ND	ND	ND
63	Propanoic acid, 2-methyl-, 3-hydroxy-2,2,4-trimethylpentyl ester	1446	ND	1.5^a ± 0.2	2^a ± 2	0.6^b ± 0.2
64	Butanoic acid, 3-methyl-, phenylmethyl ester	1463	1^a ± 0.3	ND	ND	ND
65	2,2,4-Trimethyl-1,3-pentanediol diisobutyrate	1686	ND	2.1 ^a ± 0.8	ND	ND
	Total		166.77	6.80	2.00	4.26
	Pyrazines (7)
66	Pyrazine	<800	ND	ND	5^a ± 4	ND
67	Pyrazine, methyl-	<800	6.5^b ± 0.9	8^b ± 3	15^a ± 5	7.2^b ± 0.9
68	Pyrazine, 2,5-dimethyl-	808	12.4^b ± 0.7	55^a ± 13	31^ab ± 4	36^ab ± 2
69	Pyrazine, trimethyl-	950	8.82^b ± 0.04	13^b ± 3	89^a ± 35	18^b ± 2
70	Pyrazine, 3-ethyl-2,5-dimethyl-	1060	ND	2^b ± 2	ND	4^a ± 1
71	Pyrazine, tetramethyl-	1072	7.2^b ± 0.3	3^b ± 1	196^a ± 86	5^b ± 1
72	2,3,5-Trimethyl-6-ethylpyrazine	1171	ND	ND	3^a ± 2	ND
	Total		34.92	81.00	339.00	70.20
	Alcohols (28)
73	Ethanol	<800	191^a ± 7	280^a ± 80	144^a ± 11	212^a ± 27
74	1-Butanol, 3-methyl-	<800	135 ^a ± 24	42.0^b ± 0.5	ND^c	59^b ± 83
75	1-Pentanol	<800	ND	ND	88^a ± 103	2^a ± 2
76	1-Butanol, 2-methyl-	<800	ND	ND	ND	51^a ± 68
77	Isopropyl alcohol	<800	ND	ND	25^a ± 33	ND
78	4-Penten-1-ol, 2-methyl-	<800	ND	ND	56^a ± 20	ND
79	5-Hexyn-3-ol	<800	2^a ± 2	ND	ND	ND
80	dl-2,3-Butanediol	<800	ND	ND	19^a ± 24	ND
81	Ethanol, 2-(methylthio)-	<800	1.6^b ± 0.5	ND	3.1^a ± 0.5	ND
82	1-Hexanol	<800	ND	11^a ± 3	ND	11.5^a ± 0.4
83	3-Furanmethanol	<800	6^a ± 2	ND	ND	ND
84	2,3-Butanediol	<800	ND	ND	683^a ± 60	ND
85	Ethanol, 2-butoxy-	<800	ND	2.4^a ± 0.3	11^a ± 9	1.3^a ± 0.4
86	4-Heptanol, 3,5-dimethyl-	858	6^a ± 1	ND	9^a ± 7	ND
87	2,3-Butanediol, [S-(R*,R*)]-	871	ND	ND	39^a ± 28	ND
88	2-Heptanol, 5-methyl-	887	ND	0.7^a ± 0.5	ND	ND
89	1-Butanol, 3-methyl-, propanoate	892	1.8^a ± 0.3	ND	ND	ND
90	1-Heptanol	899	1.3^a ± 0.2	ND	ND	ND
91	1-Octen-3-ol	912	2.63^a ± 0.05	2.6^a ± 0.7	3^a ± 1	3.2^a ± 0.4
92	1-Hexanol, 2-ethyl-	986	ND	12^a ± 15	22^a ± 7	27^a ± 1
93	Benzyl alcohol	1000	349^a ± 9	86^b ± 17	77^b ± 24	234^a ± 15
94	7-Octen-2-ol, 2,6-dimethyl-	1050	ND	3^a ± 1	ND	ND
95	Phenylethyl alcohol	1113	26.6^b ± 0.5	6^c ± 5	65 ^a ± 25	15^bc ± 3
96	Levomenthol	1201	0.43^b ± 0.05	0.74^a ± 0.02	0.9^a ± 0.8	ND
97	1,6-Octadien-3-ol,3,7-dimethyl-, formate	1293	1.0^a ± 0.2	ND	ND	1.0^a ± 0.3
98	1-Octanol, 2-butyl-	1369	1.1^a ± 0.2	ND	0.6^a ± 0.2	1.5^a ± 0.2
99	n-Tridecan-1-ol	1379	0.8^a ± 0.3	ND	ND	ND
100	2,2,4-Trimethyl-1,3-pentanediol diisobutyrate	1686	0.29^a ± 0.02	ND	2^a ± 2	0.8^a ± 0.3
	Total		726.55	446.44	1247.60	619.30
	Nitrogen-containing compounds (10)
101	N-Dimethylamino methyl-tert.-butyl-isopropylphosphine	<800	145^b ± 4	483^a ± 4	ND	ND
102	2-Butanamine, 2-methyl-	<800	ND	ND	ND	9^a ± 6
103	Dimethylamine	<800	7^a ± 10	ND	ND	ND
104	Urea	<800	3^a ± 2	ND	ND	ND
105	Methylamine, N,N-dimethyl-	<800	8^b ± 12	ND	ND	35^a ± 16
106	Dimethylamine	876	ND	ND	0.35^a ± 0.06	ND
107	N,Nʹ-Dibenzylidene ethylenediamine	1117	ND	ND	ND	0.5^a ± 0.3
108	Aziridine, 2-phenyl-	1317	1.3^a ± 0.8	ND	ND	ND
109	Indole	1353	ND	ND	ND	37^a ± 2
110	1-Butanamine, 3-methyl-N-(2-phenylethylidene)-	1453	ND	1.9^a ± 0.4	ND	ND
	Total		164.30	484.90	0.35	81.50
	Sulphur compounds (5)
111	Methanethiol	<800	0.6^b ± 0.1	31^a ± 42	31^a ± 11	29^a ± 3
112	Disulphide, dimethyl	<800	30^a ± 2	7.8^b ± 0.5	ND	41^a ± 15
113	Methional	<800	0.49^b ± 0.06	ND	ND	1.1^a ± 0.3
114	Benzo[b]thiophene	1221	0.41^b ± 0.09	0.59^a ± 0.01	ND	0.7^a ± 0.1
115	2-Phenyl-1-phenylsulphonylaziridine	1295	ND	2.5^b ± 0.9	ND	14^a ± 18
	Total		31.50	41.89	31.00	85.80
	Sesquiterpenes (3)
116	α-Copaene	1453	1.16^a ± 0.08	1.8^a ± 0.3	1.5^a ± 0.6	1.56^a ± 0.03
117	Aromandendrene	1552	ND	ND	0.7^a ± 0.2	1.04^a ± 0.08
118	trans-Calamenene	1619	ND	0.22^a ± 0.02	ND	0.28^a ± 0.01
	Total		1.16	2.02	2.20	2.88
	Monoterpenes (5)
119	β-Pinene	901	ND	ND	0.8^a ± 0.2	0.33^a ± 0.01
120	β-Myrcene	923	0.06^a ± 0.01	0.15^a ± 0.00	ND	0.10^a ± 0.06
121	Limonene	983	28^a ± 2	24^a ± 4	ND	26.3^a ± 0.6
122	o-Cymene	1027	2.1^b ± 0.9	7^ab ± 7	17^a ± 5	2^b ± 1
123	(+)-2-Carene	1070	ND	0.8^a ± 0.4	ND	ND
	Total		30.16	31.95	17.80	28.73
	Furans (2)
124	Furfural	<800	0.8^a ± 0.2	ND	ND	ND
125	Furan, 2-pentyl-	923	2.4^a ± 0.2	2.8^a ± 0.6	3.5^a ± 0.5	2.4^a ± 0.2
	Total		3.20	2.80	3.50	2.40

^† SFBA3: B. subtilis subsp. subtilis; PALB7: B. cereus; OALB2: B. licheniformis; SFBA2: B. amyloliquefaciens subsp. plantarum.

* RI_exp: Experimental Retention Index on an Rxi-5SilMS × Rxi-17SilMS column system using C₈–C₂₈ as external references.

^¶ Different letters in the same row indicate significant differences (p < 0.05).

ND: not detected.

Figure 1. Principal component loadings and scores of concentrations of volatile compounds in dawadawa-type condiments produced from alkaline fermentation of bambara groundnut. PALB7: with B. cereus PALB7; SFBA2: with B. amyloliquefaciens subp. plantarum SFBA2; OALB2: with B. licheniformis OALB2; and SFBA3: with B. subtilis subsp. subtilis SFBA3. Compounds 1–125, see Table 1.

Table 2. Odour thresholds and odour activity values (OAVs) of volatile compounds in dawadawa-type condiments.

	Odour threshold (µg kg^−1)*	Concentration (µg kg^−1)				OAV^¶
		SFBA3^†	PALB7	OALB2	SFBA2	SFBA3	PALB7	OALB2	SFBA2
Hexanal	4.5	40.6	53.5	52.7	38.6	9	12	12	9
Benzaldehyde	350	1205.5	2710.6	1012.8	1782.8	3	8	3	5
Benzeneacetaldehyde	4	7.6	0.8	2.1	3.5	2	<1	1	1
Nonanal	1	16.2	17.5	16.0	22.1	16	18	16	22
Heptanal	3	30.2	3.2	2.8	3.4	10	1	1	1
Decanal	0.1	1.4	3.4	3.9	5.2	14	34	39	52
Butanoic acid, 3-methyl-	120	1653.0	42.5	191.9	14.6	14	<1	2	<1
Butanoic acid, 2-methyl-	100	1649.4	23.0	39.3	11.3	16	<1	<1	<1
Acetoin	800	120.5	0.0	875.4	0.0	<1	<1	1	<1
Dimethyl disulphide	0.33	30.3	7.8	0.0	40.5	92	24	0	123

* Data taken from van Gemert and Netternbreijer^[29] and Park et al.^[23]

^¶ Odour-activity values (OAV) were calculated by dividing the concentrations by the respective odour threshold.

^† SFBA3: B. subtilis subsp. subtilis; PALB7: B. cereus; OALB2: B. licheniformis; SFBA2: B. amyloliquefaciens subsp. plantarum.

Van Gemert, L. J.; Netternbreijer, A. H. Compilation of Odour Threshold Values in Air and Water; TNO Central Institute for Nutrition and Food Research: Zeist, The Netherlands, 1977.

 Google Scholar

Park, H.-J.; Lee, S. M.; Song, S. H.; Kim, Y.-S. Characterization of Volatile Components in Makgeolli, a Traditional Korean Rice Wine, With or Without Pasteurization, During Storage. Molecules 2013, 18(5), 5317–5325. DOI: 10.3390/molecules18055317.

 PubMed Web of Science ®Google Scholar