Aroma features of honey measured by sensory evaluation, gas chromatography-mass spectrometry, and electronic nose

Figures & data

Table 1. The sensory evaluation results (Mean ± standard deviation) of five different honey.

Sensory attributes	H1	H2	H3	H4	H5
Fresh	7.2 ± 1.15^c	6.00 ± 1.98^ab	6.00 ± 1.33^ab	7.07 ± 1.28^bc	5.40 ± 1.06^a
Sweet	7.67 ± 1.43^c	6.27 ± 1.43^b	6.07 ± 0.65^b	8.00 ± 1.07^c	5.07 ± 1.41^a
Mellow	7.53 ± 0.83^c	6.20 ± 1.61^b	6.93 ± 1.58^c	6.13 ± 1.47^b	4.27 ± 1.19^a
Fruity	5.07 ± 2.09^b	5.33 ± 1.51^b	6.87 ± 2.21^c	5.47 ± 2.43^b	3.80 ± 1.20^a
Fermented	5.47 ± 1.64^a	5.20 ± 1.32^a	5.27 ± 1.16^a	5.40 ± 1.60^a	7.47 ± 1.86^b

Values in the same row with different letters (a, b, c) are significantly different (p < 0.05) according to Duncan’s multiple comparison test (n = 30: 15 panellists with 2 replications).

Table 2. Volatile compounds in the five honey samples (mg kg⁻¹, n = 3) identified by SPME/GC-MS.

Compound		ID^A	RI^B	RIcal ^C	Odor description ^D	H1	H2	H3	H4	H5
Alcohols (13)
1	Ethanol	RI, MS	898	893	Alcohol	0.981^d ± 0.014^E	0.441^b ± 0.001	0.779^c ± 0.024	0.838^c ± 0.052	0.146^a ± 0.007
2	1-propanol	RI, MS	994	990	Alcohol, ripe, fruit	0.007^c ± 0.001	nd^a	0.003^b ± 0.001	0.004^bc ± 0.001	nd^a
3	2-methyl-1-propanol	RI, MS	1121	1119	wine, Solvent, bitter	0.093^c ± 0.004	0.034^b ± 0.001	0.053^b ± 0.005	0.046^b ± 0.003	0.01 ± 0.002
4	1-butanol	RI, MS	1087	1092	Medicinal, phenolic	0.004^a ± 0.001	0.003^a ± 0.001	0.004^a ± 0.001	0.004^a ± 0.002	0.006^a ± 0.001
5	1-butanol, 3-methyl-	RI, MS	1154	1152	Fusel, alcohol, sweet, fruity	0.26^b ± 0.01	0.003^a ± 0.001	0.004^a ± 0.001	0.004^a ± 0.002	0.006^a ± 0.001
6	1-pentanol	RI, MS	1083	1080	Sweet, burning	0.003^b ± 0.001	nd^a	0.16^c ± 0.002	nd^a	0.012^b ± 0.004
7	leaf alcohol	MS		1168	Grassy-green	nd^a	0.001^b ± 0.001	nd^a	nd^a	nd^a
8	2-ethylhexanol	MS		1463	Rose, sweet	0.021^b ± 0.001	nd^a	nd^a	nd^a	nd^a
9	2,3-butanediol	RI, MS	1250	1246	burning	0.12^c ± 0.026	0.121^c ± 0.001	0.073^b ± 0.017	0.089^b ± 0.02	0.004^a ± 0.001
10	2-(4-methylphenyl)propan-2-ol	MS		1491		nd^a	0.002^b ± 0.001	nd^a	nd^a	nd^a
11	2-bornanol	RI, MS	1375	1377	Piney, camphor-like	nd^a	0.004^b ± 0.001	nd^a	nd^a	nd^a
12	furfuryl alcohol	RI, MS	1181	1178	Burnt	0.064^c ± 0.007	nd^a	nd^a	nd^a	0.031^b ± 0.005
13	2-phenylethanol	RI, MS	1946	1949	flowery, rose, honey	0.075^c ± 0.004	0.005^a ± 0.001	0.01^a ± 0.002	0.022^b ± 0.007	nd^a
Total content						1.506	0.609	1.057	0.968	0.156
Esters (9)
14	ethyl hydrogen oxalate	MS		760		nd^a	nd^a	nd^a	0.009^b ± 0.002	nd^a
15	ethyl acetate	RI, MS	864	868	Pineapple	0.149^a ± 0.006	0.042^a ± 0.001	0.156^a ± 0.008	0.153^a ± 0.011	0.017^a ± 0.002
16	ethenyl ethanoate	MS		889		0.006^b ± 0.001	nd^a	nd^a	nd^a	nd^a
17	ethyl-2-methylbutyrate	MS		939	green-fruity, apple-like	nd^a	nd^a	nd^a	nd^a	0.004^b ± 0.001
18	ethyl 3-methyl butyrate	RI, MS	1050	1049	Fruit	nd^a	nd^a	nd^a	nd^a	0.004^b ± 0.001
19	ethyl lactate	RI, MS	1347	1344	Fruit	0.029^b ± 0.012	0.012^a ± 0.001	0.009^a ± 0.001	0.047^a ± 0.009	0.002^a ± 0.001
20	ethyl benzoate	RI, MS	1558	1560	Camomile, flower, celery, fruit	0.012^ab ± 0.003	nd^a	0.015^ab ± 0.002	0.02^c ± 0.004	nd^a
21	γ-valerolactone	MS		1323	sweet, herbaceous	nd^a	nd^a	0.002^a ± 0.001	nd^a	0.014^b ± 0.001
22	bis(2-ethylhexyl) adipate	MS		2004		0.014^b ± 0.002	nd^a	nd^a	nd^a	nd^a
Total content						0.218	0.054	0.176	0.227	0.062
Aldehydes (11)
23	acetaldehyde	RI, MS	665	668	Pungent, ether	0.156^c ± 0.004	0.021^a ± 0.001	0.022^a ± 0.001	0.097^b ± 0.014	0.016^a ± 0.005
24	3-methyl-butanal	RI, MS	873	869	Fruity, fatty	0.011^a ± 0.001	0.003^a ± 0.001	nd^a	nd^a	0.079^b ± 0.002
25	hexanal	RI, MS	1061	1062	Grass, tallow, fat	0.007^b ± 0.001	0.003^ab ± 0.001	0.003^ab ± 0.001	0.005^b ± 0.001	nd^a
26	octanal	RI, MS	1280	1277	Fat, soap, lemon, green	0.008^b ± 0.001	nd^a	nd^a	nd^a	nd^a
27	1-nonanal	RI, MS	1400	1395	Fatty, citrus-like	0.003^b ± 0.001	0.001^ab ± 0.001	nd^a	0.001^ab ± 0.001	0.001^ab ± 0.001
28	furfural	RI, MS	1429	1425	Bread, almond, sweet	0.532^c ± 0.005	0.544^c ± 0.002	0.172^a ± 0.014	0.377^b ± 0.166	0.873^d ± 0.037
29	benzaldehyde	RI, MS	1460	1464	Almond, burnt sugar	0.063^b ± 0.007	0.074^b ± 0.001	0.083^b ± 0.001	nd^a	0.007^a ± 0.001
30	5-methyl furfural	MS		1594	Sweet, spicy	0.009^a ± 0.003	0.011^a ± 0.001	0.007^a ± 0.003	nd^a	0.004^a ± 0.001
31	2-phenylacetaldehyde	RI, MS	1648	1644	Hawthorne, honey, sweet	0.034^a ± 0.003	0.134^b ± 0.001	0.007^a ± 0.001	0.047^a ± 0.007	0.012^a ± 0.004
32	2-phenyl-2-butenal	MS		1573	Green, floral, woody	nd^a	0.003^b ± 0.001	nd^a	nd^a	nd^a
33	anisaldehyde	RI, MS	1674	1670	Mint, sweet	nd^a	nd^a	0.003^b ± 0.001	nd^a	nd^a
Total content						0.809	0.859	0.285	0.357	1.104
Ketones (4)
34	acetone	RI, MS	791	792	sweet, fruit	nd^a	0.023^c ± 0.001	0.005^ab ± 0.001	nd^a	0.01^b ± 0.005
35	2-pentanone	RI, MS	985	988	Ethereal, fruity	nd^a	0.013^b ± 0.001	nd^a	nd^a	nd^a
36	2,3-pentenedione	RI, MS	1047	1046	Sweet	0.006^b ± 0.001	0.006^b ± 0.001	0.003^ab ± 0.001	0.002^ab ± 0.001	nd^a
37	2-octanone	RI, MS	1106	1105	Floral and bitter, green, fruity	0.199^a ± 0.004	0.241^a ± 0.001	0.235^a ± 0.109	0.242^a ± 0.025	0.208^a ± 0.004
Total content						0.206	0.281	0.232	0.222	0.225
Acids (10)
38	acetic acid	RI, MS	1410	1412	Sour, vinegar	0.14^b ± 0.005	0.06^ab ± 0.001	0.128^ab ± 0.002	0.046^ab ± 0.003	0.04^a ± 0.002
39	sarcolactic acid	MS		1267		nd^a	nd^a	nd^a	nd^a	0.004^b ± 0.001
40	butyric acid	RI, MS	1628	1626	Rancid, cheese, sweat	nd^a	nd^a	0.004^a ± 0.001	nd^a	0.014^b ± 0.001
41	isovaleric acid	MS		1651	Sweat, acid, rancid	nd^a	nd^a	nd^a	nd^a	0.088^b ± 0.007
42	propylmalonic acid	MS		1407		nd^a	nd^a	nd^a	nd^a	0.008^b ± 0.001
43	hexanoic acid	RI, MS	1848	1851	Sharp, sour, rancid Odor. goat-like odor	nd^a	nd^a	0.002^b ± 0.001	nd^a	nd^a
44	octanoic acid	RI, MS	2063	2064	Sweat, cheese	nd^a	0.004^a ± 0.001	0.003^a ± 0.001	nd^a	0.017^b ± 0.003
45	nonanoic acid	MS		2213	Green, fat	0.006^ab ± 0.001	0.003^ab ± 0.001	0.004^ab ± 0.001	0.011^c ± 0.005	nd^a
46	6-octenoic acid, 3,7-dimethyl-	MS		1868	Green-grassy	nd^a	0.004^b ± 0.001	nd^a	nd^a	nd^a
47	geranic acid	RI, MS	1965	1966	Sweet, floral	nd^a	0.019^b ± 0.001	nd^a	nd^a	nd^a
Total content						0.151	0.091	0.138	0.049	0.181
Heterocyclic compounds (3)
48	dimethyldisulfide	RI, MS	1060	1056	Onion, cabbage, putrid	nd^a	0.003^b ± 0.001	0.003^b ± 0.001	nd^a	nd^a
49	2-acetylfuran	MS		1251	Coffee-like	0.02^c ± 0.002	0.019^ab ± 0.002	0.004^a ± 0.001	0.007^ab ± 0.003	0.016^ab ± 0.003
50	2,5-furandicarboxaldehyde	MS		1621		0.023^b ± 0.001	0.028^b ± 0.002	0.017^ab ± 0.001	nd^a	nd^a
Total content						0.04	0.05	0.024	0.026	0.019
Alkanes(2)
51	cyclohexene, 3,3,5-trimethyl-	MS		1059		nd^a	0.003^b ± 0.001	nd^a	nd^a	nd^a
52	isoprene	MS		1115		0.01^b ± 0.001	nd^a	nd^a	nd^a	nd^a
Total content						0.011	0.003	0	0	0
Phenols (3)
53	carvacrol	RI, MS	2130	2132	Pungent	nd^a	0.002^b ± 0.001	nd^a	nd^a	nd^a
54	phenol, 4-methyl-	RI, MS	2053	2049	medicine, Phenol, smoke	0.004^b ± 0.001	0.004^b ± 0.001	0.005^b ± 0.001	nd^a	0.005^b ± 0.002
55	2,4-di-tert-butylphenol	MS		1927		0.094^d ± 0.003	nd^a	0.027^bc ± 0.003	0.006^ab ± 0.001	0.04^c ±0.002
Total content						0.094	0.005	0.029	0.006	0.045

^AIdentification method: MS: identification by comparison of the experimental mass spectra with those from the Wiley7n.1 library search system; RI: identification by comparison of calculated RI of unknown compounds in samples with those of authentic reference compounds.

^BLinear retention indices of authentic reference compounds were obtained on an HP-INNOWAX capillary column (60 × 0.25 mm × 0.25 μm) with a homologous series of n-alkanes (C7-C30).

^CLinear retention indices of unknown compounds were obtained on an HP-INNOWAX capillary column (60 × 0.25 mm × 0.25 μm) with a homologous series of n-alkanes (C7-C30).

^DOdor descriptions are mainly sourced from the following literature: http://flavornet.org/flavornet.html and http://www.odour.org.uk/.

^EThe values are expressed as mean standard ± deviation (average of triplicate) and values in the same row with different letters (a, b, c, and d) are significantly different (p < 0.05) according to Duncan’s multiple comparison test.

nd: not found.

Figure 1. TIC profiles for five honey samples fractionated by SPME using DVB/CAR/PDMS fiber coating.

Figure 2. PLSR correlation loading plot of sensory attributes and volatile compounds identified by GC-MS from different honey samples. The model was derived from volatile compounds data as the X-matrix and sensory attributes and honey samples as the Y-matrix. Elipses represent R² = 0.5 and 1.0, respectively.

Figure 3. The radar fingerprints of five different honey samples. ▲ = H3; ■ = H2; ● = H5; ⋆ = H1; － = H4.

Figure 4. PLSR correlations loading plot of sensory attribute and electronic nose sensors from five honey samples. The model was derived from electronic nose sensors as the X-matrix and sensory attributes as the Y-matrix. Ellipses represent R²=0.5 and 1.0, respectively.