Journal of Chemistry

Research Article

Melissopalynological and Volatile Compounds Analysis of Buckwheat Honey from Different Geographical Origins and Their Role in Botanical Determination

Table 5

Volatile compounds identified in investigated honey samples expressed as percentages. M1–M3: multifloral honeys from Italy (Teglio-Valtellina); M4–M6: multifloral honeys from Italy (Valtellina); A1–A3: acacia honeys from Italy (Valtellina); R1–R3: rhododendron honeys from Italy (Valtellina).


Compounds	RT^a	Identification^b	Sample code
Compounds	RT^a	Identification^b	M1^c	M2^c	M3^c	M4^c	M5^c	M6^c	A1^c	A2^c	A3^c	R1^c	R2^c	R3^c

Alcohols
Ethanol	3.97	MS, LRI	25.83	15.01	6.66	30.82	28.20	34.48	13.11	15.69	9.54	40.55	32.60	38.42
2,3-Butanedione	4.98	MS, LRI	2.97	nd	0.21	nd	0.78	0.39	0.48	0.27	0.60	0.25	0.30	0.22
2-Methyl-3-buten-2-ol	7.39	MS, LRI	0.03	0.05	nd	nd	0.10	0.05	0.04	nd	0.07	0.07	0.06	0.08
1-Butanol	12.67	MS, LRI	0.08	0.06	0.08	0.5	0.68	0.41	0.45	0.11	0.78	0.38	0.25	0.68
2-Methylbutanol	14.46	MS, LRI	0.05	0.02	0.04	0.01	0.03	0.02	0.04	0.02	0.06	0.03	0.02	0.05
2-Methylpropanol	15.02	MS, LRI	nd	nd	0.05	nd	nd	nd	0.02	0.02	0.01	nd	nd	nd
3-Methylbutanol	15.41	MS, LRI	0.58	0.47	0.56	0.39	0.51	0.55	0.54	0.25	0.92	0.51	0.35	0.60
2-Methyl-2-buten-1-ol	16.78	MS, LRI	0.14	0.06	0.10	0.01	0.10	0.09	0.10	0.07	0.14	0.12	0.08	0.10
3-Methyl-2-buten-1-ol	16.94	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
2-Methylbutenol	19.09	MS, LRI	0.02	0.01	0.04	0.01	0.02	nd	0.02	0.03	0.02	0.01	nd	0.01

Total			29.70	15.68	7.74	31.73	30.42	35.99	14.80	16.46	12.14	41.92	33.66	40.16

Phenols
2-Caren-10-al	29.28	MS, LRI	0.09	nd	0.19	0.10	nd	nd	nd	nd	nd	nd	nd	nd
p-Cymen-8-ol	30.46	MS, LRI	0.06	0.05	0.08	0.05	0.10	0.07	nd	nd	nd	0.03	0.03	0.02
Phenol	32.53	MS, LRI	0.04	0.03	0.04	0.01	0.02	0.01	0.01	nd	0.02	0.02	0.05	0.01
p-Cresol	33.26	MS, LRI	0.01	0.01	nd	nd	0.01	0.01	0.01	0.01	0.01	nd	nd	0.01
Thymol	34.34	MS, LRI	nd	0.01	nd	nd	0.02	0.01	0.01	0.01	0.01	0.02	0.03	nd

Total			0.20	0.10	0.31	0.16	0.15	0.10	0.03	0.02	0.043	0.07	0.11	0.04

Ketones
2-Butanone	6.61	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
3-Hydroxy-2-butanone	17.65	MS, LRI	1.04	1.47	0.62	1.44	0.44	0.84	1.10	1.72	1.50	0.47	0.49	0.44
Hydroxyacetone	18.08	MS, LRI	1.02	0.72	1.62	1.16	0.71	nd	2.92	1.27	2.57	1.65	2.55	1.56
2-Hydroxy-3-pentanone	19.90	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
1-Hydroxy-2-butanone	20.29	MS, LRI	0.04	0.07	nd	0.01	0.10	0.05	0.05	0.02	0.10	0.11	0.08	0.10
2-Methyl-butyrolactone	25.20	MS, LRI	nd	0.05	nd	0.15	0.27	0.21	0.16	0.14	0.13	0.06	0.05	0.04
4-Oxoisophorone	27.42	MS, LRI	0.16	0.07	0.06	0.04	0.01	nd	0.02	0.01	0.01	0.06	0.01	nd

Total			2.36	2.49	2.35	2.87	1.68	1.21	4.40	3.26	4.51	3.29	3.55	2.48

Free fatty acid
Acetic acid	22.14	MS, LRI	27.4	31.32	30.48	18.50	40.64	32.56	48.12	41.40	44.83	25.63	21.53	29.74
Formic acid	23.36	MS, LRI	2.58	3.13	3.03	12.08	5.49	6.29	8.29	5.56	5.03	7.53	12.25	6.82
Propanoic acid	24.28	MS, LRI	0.72	0.75	0.79	0.16	0.41	0.78	0.71	0.43	0.99	0.40	0.41	0.40
Isobutyric acid	24.95	MS, LRI	1.00	1.20	1.80	1.22	2.30	1.26	1.30	0.49	1.11	0.49	0.32	0.35
Butanoic acid	26.19	MS, LRI	1.30	1.26	1.34	0.43	0.46	0.94	1.22	1.30	1.20	1.20	1.50	1.90
2-Propanoic acid	26.28	MS, LRI	0.05	0.02	0.08	nd	0.01	nd	0.05	0.02	0.08	0.01	0.01	nd
Isovaleric acid	27.05	MS, LRI	2.73	1.70	3.74	1.41	1.47	2.94	3.50	3.17	3.82	1.71	1.43	1.99
Pentanoic acid	28.35	MS, LRI	0.43	0.03	0.23	0.07	0.18	0.18	0.24	0.25	0.28	nd	0.02	nd
2-Butenoic acid	28.95	MS, LRI	0.02	0.03	0.02	nd	0.01	nd	nd	nd	nd	0.02	0.01	0.03
3-Methylpentanoic acid	29.40	MS, LRI	0.04	0.02	0.04	0.01	0.03	0.07	0.10	0.08	0.10	0.11	0.02	0.10
4-Methylpentanoic acid	29.58	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
4-Pentanoic acid	30.84	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
Benzyl nitrile	31.63	MS, LRI	nd	0.02	nd	nd	nd	0.01	nd	nd	nd	0.02	0.03	nd
Heptanoic acid	31.96	MS, LRI	0.10	0.08	0.10	0.02	0.05	0.04	0.10	0.11	0.18	0.12	0.11	0.14
Octanoic acid	33.05	MS, LRI	0.07	0.03	0.03	nd	0.01	0.01	0.03	0.04	0.04	0.01	0.02	nd
Nonanoic acid	34.12	MS, LRI	0.03	0.02	0.03	nd	0.02	nd	0.02	nd	0.02	0.01	0.01	nd
Benzoic acid	37.83	MS, LRI	0.07	0.08	0.07	0.03	0.05	0.04	0.07	0.07	0.07	0.08	0.08	0.08

Total			36.54	39.69	41.78	33.93	51.13	45.12	63.75	53.37	57.76	37.34	37.75	41.55

Esters
Ethyl acetate	3.04	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	0.04	0.08	0.05
Butanoic acid 3-methyl-ethyl ester	8.60	MS, LRI	nd	0.02	0.01	0.05	nd	0.03	nd	nd	0.03	nd	nd	nd
Ethyl lactate	19.65	MS, LRI	0.03	0.04	nd	0.01	nd	0.01	nd	0.02	nd	0.02	nd	0.04
Vinyl 2,2-dimethyl pentanoate	21.70	MS, LRI	0.13	0.10	0.25	nd	0.1	nd	nd	nd	nd	nd	nd	nd
Propylene carbonate	30.14	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	0.01	0.02	0.01

Total			0.16	0.16	0.26	0.06	0.10	0.04	nd	0.02	0.03	0.07	0.10	0.10

Aldehydes
Acetaldehyde	1.75	MS, LRI	0.46	0.52	0.40	0.91	0.41	0.45	nd	nd	nd	0.37	0.20	0.46
Butanal	2.86	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
2-Methylbutanal	3.37	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
3-Methylbutanal	3.45	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	0.05	0.10	0.05
Pentanal	4.79	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
Hexanal	9.01	MS, LRI	nd	nd	nd	nd	nd	nd	0.04	nd	0.07	nd	nd	0.01
2-Pentanal	11.54	MS, LRI	nd	nd	nd	nd	nd	nd	0.01	0.01	nd	nd	nd	nd
Heptanal	14.09	MS, LRI	0.03	0.01	0.02	nd	0.03	0.02	nd	nd	nd	nd	nd	nd
Nonanal	21.00	MS, LRI	0.06	0.02	0.05	0.05	nd	nd	0.08	0.15	nd	nd	nd	nd
Benzaldehyde	23.89	MS, LRI	1.19	1.06	0.70	0.40	0.96	0.53	0.86	0.60	1.11	1.70	1.10	1.30
Lilac aldehyde A	24.88	MS, LRI	1.00	1.20	0.80	0.22	1.30	1.26	0.02	0.02	0.01	nd	nd	nd
Lilac aldehyde B	25.37	MS, LRI	0.10	0.08	nd	0.02	0.06	0.04	0.07	0.09	0.07	0.16	0.03	0.10
Benzeneacetaldehyde	26.42	MS, LRI	nd	0.01	nd	0.01	0.02	0.04	0.05	0.04	0.07	0.06	0.03	0.04
Nicotinaldehyde	27.61	MS, LRI	0.50	0.34	0.60	nd	0.04	nd	nd	nd	nd	0.22	0.10	0.14
2-Methyl-2-octenedial	29.18	MS, LRI	0.10	0.03	0.10	0.01	0.10	0.11	nd	nd	nd	0.02	0.03	0.01
Phenylacetaldehyde	31.31	MS, LRI	0.03	nd	0.07	nd	nd	nd	nd	0.02	nd	nd	nd	nd
2-Pyrrolecarbaldehyde	32.69	MS, LRI	nd	0.03	nd	0.01	nd	0.01	0.02	0.02	0.01	0.01	0.02	nd
Cinnamaldehyde	32.83	MS, LRI	0.03	nd	0.02	0.03	0.05	0.01	0.01	nd	0.02	nd	0.02	nd

Total			3.50	3.30	2.76	1.65	2.97	2.47	1.16	0.96	1.37	2.59	1.63	2.11

Furans
Furan	2.19	MS, LRI	0.18	nd	0.03	nd	0.02	nd	nd	nd	nd	nd	nd	nd
Methylfuran	3.15	MS, LRI	0.81	0.27	0.30	0.25	0.15	nd	nd	nd	nd	0.13	0.10	0.25
Dihydro-2-methyl-3(2H)-furanone	17.04	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
Furfural	22.61	MS, LRI	1.42	1.71	1.13	1.07	1.30	2.19	3.41	2.06	4.77	2.56	2.53	2.50
1-(2-Furanyl)-ethanone	23.54	MS, LRI	0.05	0.10	nd	0.05	0.10	0.08	0.10	0.05	0.15	0.5	0.08	0.01
5-Methylfurfural	25.03	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
Dihydro-5-methyl-2(3H)-furanone	25.65	MS, LRI	0.75	nd	0.09	0.01	0.05	0.03	0.05	0.05	0.05	nd	nd	0.01
Dihydro-3-methyl-2(3H)-furanone	25.72	MS, LRI	0.40	0.38	0.70	0.04	0.09	0.07	nd	nd	nd	0.44	0.87	0.50
2(5H)-Furanone	28.49	MS, LRI	nd	0.03	nd	nd	0.04	0.02	nd	nd	0.02	0.01	0.02	nd
4,5-Dimethyl-2-furaldehyde	32.19	MS, LRI	nd	0.02	nd	0.02	0.03	0.02	0.04	0.02	0.05	0.07	0.08	0.05

Total			3.56	2.41	2.25	1.39	1.68	2.33	3.50	2.13	4.89	3.25	3.60	3.31

Terpenes
Verbenene	10.74	MS, LRI	nd	nd	nd	nd	0.03	0.01	nd	nd	nd	nd	nd	nd
-Phellandrene	12.91	MS, LRI	0.03	nd	0.05	nd	0.03	nd	nd	nd	nd	nd	nd	nd
-Terpinene	13.62	MS, LRI	0.06	0.01	0.03	0.04	0.02	nd	nd	0.05	0.07	nd	nd	nd
-Terpinene	16.45	MS, LRI	nd	nd	nd	nd	nd	nd	nd	0.01	nd	nd	nd	nd
Cymene	17.24	MS, LRI	0.05	0.01	0.05	nd	0.01	nd	nd	nd	nd	nd	nd	nd
cis-Linalool oxide	22.24	MS, LRI	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd	nd
trans-Linalool oxide	22.87	MS, LRI	0.19	0.10	0.25	0.03	nd	0.01	0.11	0.08	0.04	0.14	0.06	0.10
Menthofuran	23.06	MS, LRI	0.26	nd	0.50	nd	0.10	nd	nd	nd	nd	nd	nd	nd
Linalool	24.70	MS, LRI	0.75	0.20	0.23	0.12	0.18	nd	0.47	0.65	0.20	0.91	0.12	0.67
Damascenone	29.96	MS, LRI	0.02	0.02	nd	0.01	nd	0.01	nd	0.02	nd	0.13	0.10	0.12
-Terpinolene	31.77	MS, LRI	0.14	nd	0.25	nd	0.11	0.05	nd	nd	0.03	0.01	0.02	nd
Carvacrol	34.66	MS, LRI	nd	nd	0.01	nd	0.07	0.03	nd	nd	nd	nd	nd	nd

Total			1.5	0.34	1.37	0.20	0.55	0.11	0.58	0.00	0.34	1.19	0.30	0.89

Miscellanous
Dimethyl sulfide	1.93	MS, LRI	1.07	1.14	0.70	nd	1.00	nd	nd	nd	nd	0.72	0.15	1.20
Eugenol	34.45	MS, LRI	nd	0.01	nd	nd	0.01	0.01	0.01	0.02	0.01	nd	nd	nd

Total			1.07	1.15	0.70	nd	1.01	0.01	0.01	0.02	0.01	0.72	0.15	1.20

Retention time; ^bMS: mass spectrum tentatively identified using NIST 05 and Wiley 275 libraries; LRI: linear retention index.
^cNormalized amount of volatile compounds (percentage) (peak of volatile compound/total peak area of all volatile compounds) of multifloral, acacia, and rhododendron honey from Italy (Valtellina).
nd: not detected.