J Food Bioact

Journal of Food Bioactives, ISSN 2637-8752 print, 2637-8779 online

Journal website www.isnff-jfb.com

Original Research

Volume 25, March 2024, pages 25-41

A comprehensive characterization of phenolics, amino acids and other minor bioactives of selected honeys and identification of botanical origin markers

Figure 1. MS/MS spectra of selected phenolic compounds and 5-HMF. (a) p-Hydroxybenzoic acid; (b) Caffeic acid; (c) p-Coumaric acid; (d) Isoferulic acid; (e) Hesperidin; (f) Pinobanksin-5-methyl ether; (g) Pinobanksin; (h) Kaempferol; (i) Pinocembrin; (j) Chrysin; (k) Galangin; (l) 5-HMF.

Figure 2. Principal component analysis biplots of phenolics (a) and free amino acids (b) contents in honey varieties. CA: caffeic acid, CHR: Chrysin, GAL: Galangin, HES: hesperidin, IFA: isoferulic acid, KAE: Kaempferol, pCMA: p-coumaric acid, pHBA: p-hydroxybenzoic acid, P5ME: pinobanksin-5-methyl ether, PBK: Pinobanksin, PCB: Pinocembrin. Ala: alanine, Arg: arginine, Asn: asparagine, Asp: aspartic acid, Cys: cysteine, Gln: glutamine, Glu: glutamic acid, Gly: glycine, His: histidine, Ile: isoleucine, Leu: leucine, Lys: lysine, Met: methionine, Nva: norvaline, Phe: phenylalanine, Pro: proline, Ser: serine, Thr: threonine, Trp: tryptophan, Tyr: tyrosine, Val: valine.

Figure 3. HPLC chromatograms of amino acid standards (A) and free amino acids with spiked internal standard of L-norvaline in honey varieties of alfalfa (B), clover (C), orange (D), wildflower (E), and buckwheat (F), as well as buckwheat honey without internal standard of norvaline (G). The HPLC peaks represent L-amino acid of histidine (1), asparagine (2), arginine (3), serine (4), glycine (5), glutamine (6), aspartic acid (7), glutamic acid (8), threonine (9), alanine (10), proline (11), lysine (12), cysteine (13), methionine (14), tyrosine (15), valine (16), norvaline (17), isoleucine (18), leucine (19), phenylalanine (20), and tryptophan (21).

Figure 4. MS/MS spectra of diluted buckwheat honey samples (a), L-norvaline standard (b) and an unknown compound eluted earlier than L-norvaline but contributing a background at m/z 118.0864 (c).

**Table 1.** Total phenolic and protein contents of honeys
	Mean ± SD
Means followed by a common letter within the same row are not significantly different by the Tukey’s HSD test at the 5% level of significance.
TPC (µg GAE/g)	379.4 ± 42.2a	1269.1 ± 275.3b	425.4 ± 89.1a	414.6 ± 34.8a	507.0 ± 120.5a
Protein (µg/g)	3807.9 ± 420.0a	8830.7 ± 537.3b	4172.3 ± 357.3a	4346.6 ± 804.7a	5158.6 ± 252.1a

Table 1. Total phenolic and protein contents of honeys

Mean ± SD

Alfalfa

Buckwheat

Clover

Orange

Wildflower

Means followed by a common letter within the same row are not significantly different by the Tukey’s HSD test at the 5% level of significance.

TPC (µg GAE/g)

379.4 ± 42.2a

1269.1 ± 275.3b

425.4 ± 89.1a

414.6 ± 34.8a

507.0 ± 120.5a

Protein (µg/g)

3807.9 ± 420.0a

8830.7 ± 537.3b

4172.3 ± 357.3a

4346.6 ± 804.7a

5158.6 ± 252.1a

**Table 2.** Identification of phenolic compounds, abscisic acid, furfural, and 5-HMF in honey by LC-MS
Peak	t_R (min)	λ_max (nm)	Formula	[M-H]^- m/z	Major fragment ions
*Positive ionization mode was used ([M+H]⁺).
Gallic acid	4.63	270	C₇H₆O₅	169.0141	125.0245
Protocatechuic acid	7.00	260	C₇H₆O₄	153.0194	109.0296
5-HMF	7.49	285	C₆H₆O₃	127.0390*	109.0286, 81.0340
Furfural	8.24	275	C₅H₄O₂	97.0286*	69.0342
Neochlorogenic acid	8.65	325	C₁₆H₁₈O₉	353.0878	191.0564, 179.0353, 135.0452
p-Hydroxybenzoic acid	9.70	255	C₇H₆O₃	137.0242	93.0348
Vanillic acid	12.66	260	C₈H₈O₄	167.0348	152.0118, 123.0452, 108.0220
Caffeic acid	13.00	320	C₉H₈O₄	179.0352	135.0452
Chlorogenic acid	13.10	325	C₁₆H₁₈O₉	353.0878	191.0563
Syringic acid	15.09	270	C₉H₁₀O₅	197.0452	182.0223
p-Coumaric_acid	17.81	310	C₉H₈O₃	163.0401	119.0502
trans-Ferulic acid	19.79	320	C₁₀H₁₀O₄	193.0505	178.0274, 149.0611, 134.0374
Isoferulic acid	21.34	320	C₁₀H₁₀O₄	193.0506	178.0274, 134.0374
o-Coumaric acid	22.83	275	C₉H₈O₃	163.0401	119.0502
Ellagic acid	25.59	250	C₁₄H₆O₈	300.9990	155.1080
Hesperidin	25.66	280	C₂₈H₃₄O₁₅	609.1825	301.0723
Myricetin	26.35	250, 370	C₁₅H₁₀O₈	317.0305	178.9989, 151.0039, 137.0245
Kaempferol-rutinoside	27.47	265, 345	C₂₇H₃₀O₁₅	593.1512	285.0407, 284.0328
Abscisic acid	27.75	260	C₁₅H₂₀O₄	263.1289	219.1394, 204.1159, 151.0768
Pinobanksin-5-methyl ether	28.80	285	C₁₆H₁₄O₅	285.0768	267.0663, 252.0430
Pinobanksin	29.56	290	C₁₅H₁₀O₇	301.0354	253.0507
Quercetin	29.73	250, 370	C₁₅H₁₂O₅	271.0612	178.9989, 151.0039
Naringenin	29.97	290	C₁₅H₁₂O₅	271.0612	151.0039, 119.0502
Luteolin	31.18	250, 350	C₁₅H₁₀O₆	285.0406	133.0293
Hesperetin	31.34	285	C₁₆H₁₄O₆	301.0718	286.0485, 151.0039
Kaempferol	32.59	265, 365	C₁₅H₁₀O₆	285.0406	151.0039
Apigenin	33.23	265, 340	C₁₅H₁₀O₅	269.0455	151.0038
Isohamnetin	33.51	250, 370	C₁₆H₁₂O₇	315.0512	300.0282
Pinocembrin	35.31	285	C₁₅H₁₂O₄	255.0663	213.0560, 151.0039
Chrysin	36.73	265	C₁₅H₁₀O₄	253.0507	209.0611
Galangin	36.91	265, 360	C₁₅H₁₀O₅	269.0453	-
Acacetin	37.25	265, 330	C₁₆H₁₂O₅	283.0613	268.0377

Table 2. Identification of phenolic compounds, abscisic acid, furfural, and 5-HMF in honey by LC-MS

Peak

t_R (min)

λ_max (nm)

Formula

[M-H]^- m/z

Major fragment ions

*Positive ionization mode was used ([M+H]⁺).

Gallic acid

4.63

270

C₇H₆O₅

169.0141

125.0245

Protocatechuic acid

7.00

260

C₇H₆O₄

153.0194

109.0296

5-HMF

7.49

285

C₆H₆O₃

127.0390*

109.0286, 81.0340

Furfural

8.24

275

C₅H₄O₂

97.0286*

69.0342

Neochlorogenic acid

8.65

325

C₁₆H₁₈O₉

353.0878

191.0564, 179.0353, 135.0452

p-Hydroxybenzoic acid

9.70

255

C₇H₆O₃

137.0242

93.0348

Vanillic acid

12.66

260

C₈H₈O₄

167.0348

152.0118, 123.0452, 108.0220

Caffeic acid

13.00

320

C₉H₈O₄

179.0352

135.0452

Chlorogenic acid

13.10

325

C₁₆H₁₈O₉

353.0878

191.0563

Syringic acid

15.09

270

C₉H₁₀O₅

197.0452

182.0223

p-Coumaric_acid

17.81

310

C₉H₈O₃

163.0401

119.0502

trans-Ferulic acid

19.79

320

C₁₀H₁₀O₄

193.0505

178.0274, 149.0611, 134.0374

Isoferulic acid

21.34

320

C₁₀H₁₀O₄

193.0506

178.0274, 134.0374

o-Coumaric acid

22.83

275

C₉H₈O₃

163.0401

119.0502

Ellagic acid

25.59

250

C₁₄H₆O₈

300.9990

155.1080

Hesperidin

25.66

280

C₂₈H₃₄O₁₅

609.1825

301.0723

Myricetin

26.35

250, 370

C₁₅H₁₀O₈

317.0305

178.9989, 151.0039, 137.0245

Kaempferol-rutinoside

27.47

265, 345

C₂₇H₃₀O₁₅

593.1512

285.0407, 284.0328

Abscisic acid

27.75

260

C₁₅H₂₀O₄

263.1289

219.1394, 204.1159, 151.0768

Pinobanksin-5-methyl ether

28.80

285

C₁₆H₁₄O₅

285.0768

267.0663, 252.0430

Pinobanksin

29.56

290

C₁₅H₁₀O₇

301.0354

253.0507

Quercetin

29.73

250, 370

C₁₅H₁₂O₅

271.0612

178.9989, 151.0039

Naringenin

29.97

290

C₁₅H₁₂O₅

271.0612

151.0039, 119.0502

Luteolin

31.18

250, 350

C₁₅H₁₀O₆

285.0406

133.0293

Hesperetin

31.34

285

C₁₆H₁₄O₆

301.0718

286.0485, 151.0039

Kaempferol

32.59

265, 365

C₁₅H₁₀O₆

285.0406

151.0039

Apigenin

33.23

265, 340

C₁₅H₁₀O₅

269.0455

151.0038

Isohamnetin

33.51

250, 370

C₁₆H₁₂O₇

315.0512

300.0282

Pinocembrin

35.31

285

C₁₅H₁₂O₄

255.0663

213.0560, 151.0039

Chrysin

36.73

265

C₁₅H₁₀O₄

253.0507

209.0611

Galangin

36.91

265, 360

C₁₅H₁₀O₅

269.0453

Acacetin

37.25

265, 330

C₁₆H₁₂O₅

283.0613

268.0377

**Table 3.** Quantification of phenolic compounds, abscisic acid, furfural, and 5-HMF in honey by LC-MS
	Concentration (µg/g Honey), Mean ± SD
n.d. = not detected. Means followed by a common letter within the same row are not significantly different by the Tukey’s HSD test at the 5% level of significance.
Phenolic compounds
Gallic acid	0.049 ± 0.028^a	0.034 ± 0.001^a	0.038 ± 0.040^a	0.046 ± 0.021^a	0.017 ± 0.004^a
Protocatechuic acid	0.297 ± 0.076^ab	0.400 ± 0.021^ab	0.266 ± 0.112^a	0.695 ± 0.288^b	0.338 ± 0.056^ab
Neochlorogenic acid	0.025 ± 0.003^a	0.128 ± 0.083^a	0.037 ± 0.014^a	0.100 ± 0.078^a	0.321 ± 0.339^a
p-Hydroxybenzoic acid	1.734 ± 0.494^a	12.483 ± 4.230^b	2.562 ± 0.394^a	1.166 ± 0.625^a	3.139 ± 1.415^a
Vanillic acid	0.148 ± 0.028^a	0.232 ± 0.025^a	0.583 ± 0.071^b	0.266 ± 0.080^ac	0.507 ± 0.190^bc
Caffeic acid	6.884 ± 0.320^a	1.092 ± 0.082^b	1.945 ± 1.259^b	0.384 ± 0.232^b	1.185 ± 0.603^b
Chlorogenic acid	0.084 ± 0.006^a	0.336 ± 0.208^a	0.093 ± 0.028^a	0.104 ± 0.032^a	0.811 ± 0.728^a
Syringic acid	0.179 ± 0.066^a	0.221 ± 0.120^a	0.283 ± 0.058^a	0.157 ± 0.094^a	0.283 ± 0.029^a
p-Coumaric acid	1.673 ± 0.313^ab	4.910 ± 1.224^c	3.230 ± 0.714^ac	0.847 ± 0.672^b	1.993 ± 0.447^ab
Trans-Ferulic acid	0.360 ± 0.017^a	0.346 ± 0.048^a	0.731 ± 0.170^b	0.222 ± 0.163^a	0.493 ± 0.135^ab
Isoferulic acid	3.262 ± 0.228^a	0.179 ± 0.080^b	0.615 ± 0.677^b	n.d.	0.214 ± 0.174^b
o-Coumaric acid	0.019 ± 0.008^a	0.029 ± 0.006^a	0.118 ± 0.046^b	0.003 ± 0.002^a	0.063 ± 0.029^ab
Ellagic acid	0.040 ± 0.008^a	0.089 ± 0.066^a	0.098 ± 0.086^a	0.122 ± 0.034^a	0.157 ± 0.153^a
Hesperidin	0.063 ± 0.109^a	n.d.	0.011 ± 0.013^a	1.981 ± 0.234^b	n.d.
Myricetin	0.089 ± 0.093^a	0.129 ± 0.095^a	0.058 ± 0.024^a	0.016 ± 0.018^a	0.126 ± 0.073^a
Kaempferol-rutinoside	0.020 ± 0.019^ab	0.008 ± 0.014^a	0.035 ± 0.012^ab	0.049 ± 0.014^b	0.038 ± 0.016^ab
P5ME	1.448 ± 0.482^ab	1.997 ± 0.421^a	2.497 ± 0.804^a	0.337 ± 0.419^b	0.979 ± 0.111^ab
Pinobanksin	7.259 ± 1.003^a	5.155 ± 1.694^ac	7.481 ± 1.527^a	1.012 ± 1.298^b	2.539 ± 0.333^bc
Quercetin	0.625 ± 0.148^a	0.950 ± 0.211^a	0.929 ± 0.170^a	0.496 ± 0.284^a	1.076 ± 0.181^a
Naringenin	0.037 ± 0.064^a	0.033 ± 0.056^a	0.111 ± 0.079^a	0.023 ± 0.039^a	0.055 ± 0.077^a
Luteolin	0.143 ± 0.013^a	0.118 ± 0.024^a	0.150 ± 0.048^a	0.185 ± 0.099^ab	0.348 ± 0.130^a
Hesperetin	0.037 ± 0.011^a	0.007 ± 0.000^a	0.012 ± 0.006^a	0.218 ± 0.075^b	0.009 ± 0.001^a
Kaempferol	3.444 ± 1.052^ab	4.380 ± 0.343^a	4.784 ± 0.801^a	0.906 ± 0.338^b	4.369 ± 2.180^a
Apigenin	0.876 ± 0.340^a	0.531 ± 0.157^ab	0.653 ± 0.042^a	0.123 ± 0.103^b	0.589 ± 0.023^ab
Isorhamnetin	0.469 ± 0.076^ab	0.590 ± 0.075^a	0.765 ± 0.100^a	0.209 ± 0.187^b	0.464 ± 0.035^ab
Pinocembrin	6.468 ± 1.570^ab	5.618 ± 1.309^ab	7.514 ± 1.503^a	0.985 ± 1.322^c	2.794 ± 0.028^bc
Chrysin	2.052 ± 0.269^ab	1.883 ± 0.295^ab	2.159 ± 0.455^a	0.229 ± 0.215^c	1.116 ± 0.096^bc
Galangin	1.932 ± 0.227^a	1.656 ± 0.206^ab	2.005 ± 0.431^a	0.194 ± 0.199^c	0.875 ± 0.057^bc
Acacetin	0.263 ± 0.439^a	0.287 ± 0.209^a	0.024 ± 0.008^a	0.006 ± 0.004^a	0.008 ± 0.001^a
Sub-total	39.982 ± 4.252^ab	43.820 ± 8.674^a	39.786 ± 4.316^ab	11.080 ± 6.862^c	24.903 ± 2.246^bc
Non-phenolics
5-HMF	10.059 ± 5.582^a	4.407 ± 4.744^a	6.317 ± 4.609^a	9.658 ± 1.285^a	4.131 ± 2.466^a
Furfural	0.956 ± 0.331^a	8.124 ± 2.575^b	0.858 ± 0.419^a	0.873 ± 0.324^a	0.977 ± 0.078^a
Abscisic acid	1.147 ± 0.595^a	1.080 ± 0.774^a	1.354 ± 0.945^a	7.634 ± 2.400^b	0.849 ± 0.172^a

Table 3. Quantification of phenolic compounds, abscisic acid, furfural, and 5-HMF in honey by LC-MS

Concentration (µg/g Honey), Mean ± SD

Alfalfa

Buckwheat

Clover

Orange

Wildflower

n.d. = not detected. Means followed by a common letter within the same row are not significantly different by the Tukey’s HSD test at the 5% level of significance.

Phenolic compounds

Gallic acid

0.049 ± 0.028^a

0.034 ± 0.001^a

0.038 ± 0.040^a

0.046 ± 0.021^a

0.017 ± 0.004^a

Protocatechuic acid

0.297 ± 0.076^ab

0.400 ± 0.021^ab

0.266 ± 0.112^a

0.695 ± 0.288^b

0.338 ± 0.056^ab

Neochlorogenic acid

0.025 ± 0.003^a

0.128 ± 0.083^a

0.037 ± 0.014^a

0.100 ± 0.078^a

0.321 ± 0.339^a

p-Hydroxybenzoic acid

1.734 ± 0.494^a

12.483 ± 4.230^b

2.562 ± 0.394^a

1.166 ± 0.625^a

3.139 ± 1.415^a

Vanillic acid

0.148 ± 0.028^a

0.232 ± 0.025^a

0.583 ± 0.071^b

0.266 ± 0.080^ac

0.507 ± 0.190^bc

Caffeic acid

6.884 ± 0.320^a

1.092 ± 0.082^b

1.945 ± 1.259^b

0.384 ± 0.232^b

1.185 ± 0.603^b

Chlorogenic acid

0.084 ± 0.006^a

0.336 ± 0.208^a

0.093 ± 0.028^a

0.104 ± 0.032^a

0.811 ± 0.728^a

Syringic acid

0.179 ± 0.066^a

0.221 ± 0.120^a

0.283 ± 0.058^a

0.157 ± 0.094^a

0.283 ± 0.029^a

p-Coumaric acid

1.673 ± 0.313^ab

4.910 ± 1.224^c

3.230 ± 0.714^ac

0.847 ± 0.672^b

1.993 ± 0.447^ab

Trans-Ferulic acid

0.360 ± 0.017^a

0.346 ± 0.048^a

0.731 ± 0.170^b

0.222 ± 0.163^a

0.493 ± 0.135^ab

Isoferulic acid

3.262 ± 0.228^a

0.179 ± 0.080^b

0.615 ± 0.677^b

n.d.

0.214 ± 0.174^b

o-Coumaric acid

0.019 ± 0.008^a

0.029 ± 0.006^a

0.118 ± 0.046^b

0.003 ± 0.002^a

0.063 ± 0.029^ab

Ellagic acid

0.040 ± 0.008^a

0.089 ± 0.066^a

0.098 ± 0.086^a

0.122 ± 0.034^a

0.157 ± 0.153^a

Hesperidin

0.063 ± 0.109^a

n.d.

0.011 ± 0.013^a

1.981 ± 0.234^b

n.d.

Myricetin

0.089 ± 0.093^a

0.129 ± 0.095^a

0.058 ± 0.024^a

0.016 ± 0.018^a

0.126 ± 0.073^a

Kaempferol-rutinoside

0.020 ± 0.019^ab

0.008 ± 0.014^a

0.035 ± 0.012^ab

0.049 ± 0.014^b

0.038 ± 0.016^ab

P5ME

1.448 ± 0.482^ab

1.997 ± 0.421^a

2.497 ± 0.804^a

0.337 ± 0.419^b

0.979 ± 0.111^ab

Pinobanksin

7.259 ± 1.003^a

5.155 ± 1.694^ac

7.481 ± 1.527^a

1.012 ± 1.298^b

2.539 ± 0.333^bc

Quercetin

0.625 ± 0.148^a

0.950 ± 0.211^a

0.929 ± 0.170^a

0.496 ± 0.284^a

1.076 ± 0.181^a

Naringenin

0.037 ± 0.064^a

0.033 ± 0.056^a

0.111 ± 0.079^a

0.023 ± 0.039^a

0.055 ± 0.077^a

Luteolin

0.143 ± 0.013^a

0.118 ± 0.024^a

0.150 ± 0.048^a

0.185 ± 0.099^ab

0.348 ± 0.130^a

Hesperetin

0.037 ± 0.011^a

0.007 ± 0.000^a

0.012 ± 0.006^a

0.218 ± 0.075^b

0.009 ± 0.001^a

Kaempferol

3.444 ± 1.052^ab

4.380 ± 0.343^a

4.784 ± 0.801^a

0.906 ± 0.338^b

4.369 ± 2.180^a

Apigenin

0.876 ± 0.340^a

0.531 ± 0.157^ab

0.653 ± 0.042^a

0.123 ± 0.103^b

0.589 ± 0.023^ab

Isorhamnetin

0.469 ± 0.076^ab

0.590 ± 0.075^a

0.765 ± 0.100^a

0.209 ± 0.187^b

0.464 ± 0.035^ab

Pinocembrin

6.468 ± 1.570^ab

5.618 ± 1.309^ab

7.514 ± 1.503^a

0.985 ± 1.322^c

2.794 ± 0.028^bc

Chrysin

2.052 ± 0.269^ab

1.883 ± 0.295^ab

2.159 ± 0.455^a

0.229 ± 0.215^c

1.116 ± 0.096^bc

Galangin

1.932 ± 0.227^a

1.656 ± 0.206^ab

2.005 ± 0.431^a

0.194 ± 0.199^c

0.875 ± 0.057^bc

Acacetin

0.263 ± 0.439^a

0.287 ± 0.209^a

0.024 ± 0.008^a

0.006 ± 0.004^a

0.008 ± 0.001^a

Sub-total

39.982 ± 4.252^ab

43.820 ± 8.674^a

39.786 ± 4.316^ab

11.080 ± 6.862^c

24.903 ± 2.246^bc

Non-phenolics

5-HMF

10.059 ± 5.582^a

4.407 ± 4.744^a

6.317 ± 4.609^a

9.658 ± 1.285^a

4.131 ± 2.466^a

Furfural

0.956 ± 0.331^a

8.124 ± 2.575^b

0.858 ± 0.419^a

0.873 ± 0.324^a

0.977 ± 0.078^a

Abscisic acid

1.147 ± 0.595^a

1.080 ± 0.774^a

1.354 ± 0.945^a

7.634 ± 2.400^b

0.849 ± 0.172^a

**Table 4.** Intrinsic free amino acid and hydrolyzed amino acid concentrations in honey by HPLC
	Alfalfa	Buckwheat	Clover	Orange	Wildflower
n.d. = not detected. Means followed by a common letter within the same row are not significantly different by the Tukey’s HSD test at the 5% level of significance.
Intrinsic free amino acids (µg/g Honey), Mean ± SD
Ala	13.37 ± 2.54^ab	31.67 ± 6.70^c	12.52 ± 2.30^ab	10.21 ± 0.64^b	29.48 ± 15.52^ac
Arg	14.76 ± 5.02^a	15.05 ± 4.29^a	17.00 ± 3.62^a	16.81 ± 4.62^a	14.53 ± 2.77^a
Asn	40.76 ± 11.78^a	49.29 ± 12.67^a	52.98 ± 36.76^a	34.18 ± 7.05^a	71.59 ± 44.39^a
Asp	37.65 ± 2.13^a	24.49 ± 4.43^a	21.86 ± 4.45^a	16.86 ± 0.66^a	30.27 ± 8.29^a
Cys	n.d.	0.50 ± 0.87	n.d.	n.d.	n.d.
Gln	7.51 ± 0.96^a	72.00 ± 31.07^a	20.69 ± 6.44^a	12.01 ± 1.81^a	69.52 ± 64.61^a
Glu	26.11 ± 5.20^a	22.21 ± 3.25^ab	23.92 ± 5.48^a	10.04 ± 3.73^b	28.51 ± 9.67^a
Gly	18.90 ± 12.41^a	30.78 ± 11.53^a	12.70 ± 0.52^a	18.08 ± 11.15^a	14.14 ± 1.06^a
His	16.46 ± 2.26^a	15.89 ± 2.06^a	18.20 ± 5.59^a	14.73 ± 2.31^a	23.64 ± 9.17^a
Ile	4.70 ± 0.94^a	98.26 ± 36.83^b	11.70 ± 6.12^a	3.88 ± 0.57^a	20.39 ± 13.14^a
Leu	5.89 ± 0.99^a	115.26 ± 47.07^b	15.58 ± 8.15^a	5.90 ± 0.75^a	22.59 ± 12.45^a
Lys	12.83 ± 0.50^ab	14.04 ± 2.43^ab	17.34 ± 2.90^a	8.50 ± 1.89^b	15.13 ± 1.43^a
Met	n.d.	0.47 ± 0.81	n.d.	n.d.	n.d.
Nva	n.d.	38.98 ± 13.21	n.d.	n.d.	n.d.
Phe	32.17 ± 15.22^a	147.10 ± 7.10^a	252.65 ± 272.37^a	60.82 ± 31.64^a	152.04 ± 26.32^a
Pro	449.26 ± 117.20^ab	473.33 ± 18.42^ab	367.73 ± 68.07^ab	286.94 ± 33.57^a	547.05 ± 162.43^b
Ser	17.48 ± 3.52^a	34.82 ± 4.65^a	19.87 ± 2.50^a	18.28 ± 1.74^a	35.82 ± 19.83^a
Thr	8.25 ± 0.23^a	21.52 ± 1.46^a	8.41 ± 1.74^a	5.84 ± 0.22^a	28.10 ± 25.85^a
Trp	n.d.	n.d.	9.88 ± 14.69^a	0.28 ± 0.48^a	2.37 ± 0.00^a
Tyr	13.32 ± 2.86^a	153.26 ± 35.56^b	77.82 ± 77.82^ab	19.48 ± 10.27^a	63.83 ± 21.18^ab
Val	8.27 ± 0.87^a	63.03 ± 12.36^b	14.15 ± 6.98^a	6.98 ± 0.69^a	19.86 ± 7.26^a
Total	727.68 ± 133.58^ab	1421.93 ± 53.53^a	975.01 ± 496.75^ab	549.82 ± 72.71^b	1188.86 ± 442.49^ab
Amino acids after hydrolysis (µg/g Honey), Mean ± SD
Ala	55.44 ± 13.80^a	177.78 ± 38.20^b	60.77 ± 7.57^a	46.26 ± 11.83^a	103.33 ± 34.11^a
Arg	40.82 ± 23.44^a	115.89 ± 8.45^b	46.80 ± 12.29^a	41.25 ± 3.94^a	68.80 ± 8.31^a
Asn	n.d.	n.d.	n.d.	n.d.	n.d.
Asp	214.19 ± 28.04^a	517.61 ± 135.17^b	218.58 ± 43.49^a	149.42 ± 31.30^a	340.40 ± 144.19^ab
Cys	18.06 ± 3.72^a	25.81 ± 1.40^a	20.84 ± 2.13^a	25.15 ± 5.87^a	28.80 ± 4.62^a
Gln	n.d.	n.d.	n.d.	n.d.	n.d.
Glu	182.59 ± 29.73^ab	510.71 ± 58.82^c	175.50 ± 19.44^ab	130.85 ± 24.62^a	396.76 ± 249.22^bc
Gly	74.69 ± 33.20^a	223.50 ± 7.03^b	58.32 ± 7.88^a	75.41 ± 37.57^a	78.72 ± 25.83^a
His	21.45 ± 1.60^a	66.00 ± 5.04^b	28.57 ± 7.98^a	25.22 ± 4.29^a	52.33 ± 28.65^ab
Ile	47.46 ± 9.29^a	290.31 ± 121.12^b	59.80 ± 11.22^a	37.20 ± 7.42^a	109.21 ± 15.21^a
Leu	72.55 ± 11.86^a	440.89 ± 166.35^b	88.96 ± 15.60^a	58.02 ± 10.82^a	138.27 ± 41.57^a
Lys	62.43 ± 11.01^a	135.83 ± 1.66^b	71.85 ± 14.99^a	55.50 ± 3.66^a	91.57 ± 28.20^a
Met	21.59 ± 4.40^a	68.44 ± 28.82^b	24.64 ± 5.93^a	25.20 ± 9.15^a	39.07 ± 0.62^ab
Nva	n.d.	40.08 ± 13.63	n.d.	n.d.	n.d.
Phe	95.33 ± 38.46^a	421.42 ± 56.81^a	325.09 ± 276.17^a	132.04 ± 48.79^a	300.36 ± 81.98^a
Pro	450.57 ± 106.69^ab	624.57 ± 63.12^a	400.83 ± 76.80^ab	313.10 ± 45.34^b	614.20 ± 237.51^ab
Ser	75.63 ± 12.49^a	243.24 ± 36.73^b	77.29 ± 9.98^a	59.12 ± 5.17^a	126.10 ± 47.49^a
Thr	50.64 ± 9.38^a	208.31 ± 45.25^b	52.45 ± 7.17^a	39.80 ± 4.42^a	101.53 ± 51.10^a
Trp	n.d.	n.d.	n.d.	n.d.	n.d.
Tyr	37.72 ± 15.45^a	221.64 ± 82.85^b	90.91 ± 38.34^a	51.27 ± 25.95^a	109.82 ± 16.94^ab
Val	58.00 ± 9.68^a	296.08 ± 86.44^b	68.71 ± 13.77^a	52.10 ± 3.56^a	107.82 ± 35.99^a
Total	1579.16 ± 299.20^a	4628.11 ± 918.98^b	1869.91 ± 451.09^a	1316.89 ± 186.77^a	2807.10 ± 1041.06^a

Table 4. Intrinsic free amino acid and hydrolyzed amino acid concentrations in honey by HPLC

Alfalfa

Buckwheat

Clover

Orange

Wildflower

n.d. = not detected. Means followed by a common letter within the same row are not significantly different by the Tukey’s HSD test at the 5% level of significance.

Intrinsic free amino acids (µg/g Honey), Mean ± SD

Ala

13.37 ± 2.54^ab

31.67 ± 6.70^c

12.52 ± 2.30^ab

10.21 ± 0.64^b

29.48 ± 15.52^ac

Arg

14.76 ± 5.02^a

15.05 ± 4.29^a

17.00 ± 3.62^a

16.81 ± 4.62^a

14.53 ± 2.77^a

Asn

40.76 ± 11.78^a

49.29 ± 12.67^a

52.98 ± 36.76^a

34.18 ± 7.05^a

71.59 ± 44.39^a

Asp

37.65 ± 2.13^a

24.49 ± 4.43^a

21.86 ± 4.45^a

16.86 ± 0.66^a

30.27 ± 8.29^a

Cys

n.d.

0.50 ± 0.87

n.d.

Gln

7.51 ± 0.96^a

72.00 ± 31.07^a

20.69 ± 6.44^a

12.01 ± 1.81^a

69.52 ± 64.61^a

Glu

26.11 ± 5.20^a

22.21 ± 3.25^ab

23.92 ± 5.48^a

10.04 ± 3.73^b

28.51 ± 9.67^a

Gly

18.90 ± 12.41^a

30.78 ± 11.53^a

12.70 ± 0.52^a

18.08 ± 11.15^a

14.14 ± 1.06^a

His

16.46 ± 2.26^a

15.89 ± 2.06^a

18.20 ± 5.59^a

14.73 ± 2.31^a

23.64 ± 9.17^a

Ile

4.70 ± 0.94^a

98.26 ± 36.83^b

11.70 ± 6.12^a

3.88 ± 0.57^a

20.39 ± 13.14^a

Leu

5.89 ± 0.99^a

115.26 ± 47.07^b

15.58 ± 8.15^a

5.90 ± 0.75^a

22.59 ± 12.45^a

Lys

12.83 ± 0.50^ab

14.04 ± 2.43^ab

17.34 ± 2.90^a

8.50 ± 1.89^b

15.13 ± 1.43^a

Met

n.d.

0.47 ± 0.81

n.d.

Nva

n.d.

38.98 ± 13.21

n.d.

Phe

32.17 ± 15.22^a

147.10 ± 7.10^a

252.65 ± 272.37^a

60.82 ± 31.64^a

152.04 ± 26.32^a

Pro

449.26 ± 117.20^ab

473.33 ± 18.42^ab

367.73 ± 68.07^ab

286.94 ± 33.57^a

547.05 ± 162.43^b

Ser

17.48 ± 3.52^a

34.82 ± 4.65^a

19.87 ± 2.50^a

18.28 ± 1.74^a

35.82 ± 19.83^a

Thr

8.25 ± 0.23^a

21.52 ± 1.46^a

8.41 ± 1.74^a

5.84 ± 0.22^a

28.10 ± 25.85^a

Trp

n.d.

9.88 ± 14.69^a

0.28 ± 0.48^a

2.37 ± 0.00^a

Tyr

13.32 ± 2.86^a

153.26 ± 35.56^b

77.82 ± 77.82^ab

19.48 ± 10.27^a

63.83 ± 21.18^ab

Val

8.27 ± 0.87^a

63.03 ± 12.36^b

14.15 ± 6.98^a

6.98 ± 0.69^a

19.86 ± 7.26^a

Total

727.68 ± 133.58^ab

1421.93 ± 53.53^a

975.01 ± 496.75^ab

549.82 ± 72.71^b

1188.86 ± 442.49^ab

Amino acids after hydrolysis (µg/g Honey), Mean ± SD

Ala

55.44 ± 13.80^a

177.78 ± 38.20^b

60.77 ± 7.57^a

46.26 ± 11.83^a

103.33 ± 34.11^a

Arg

40.82 ± 23.44^a

115.89 ± 8.45^b

46.80 ± 12.29^a

41.25 ± 3.94^a

68.80 ± 8.31^a

Asn

n.d.

Asp

214.19 ± 28.04^a

517.61 ± 135.17^b

218.58 ± 43.49^a

149.42 ± 31.30^a

340.40 ± 144.19^ab

Cys

18.06 ± 3.72^a

25.81 ± 1.40^a

20.84 ± 2.13^a

25.15 ± 5.87^a

28.80 ± 4.62^a

Gln

n.d.

Glu

182.59 ± 29.73^ab

510.71 ± 58.82^c

175.50 ± 19.44^ab

130.85 ± 24.62^a

396.76 ± 249.22^bc

Gly

74.69 ± 33.20^a

223.50 ± 7.03^b

58.32 ± 7.88^a

75.41 ± 37.57^a

78.72 ± 25.83^a

His

21.45 ± 1.60^a

66.00 ± 5.04^b

28.57 ± 7.98^a

25.22 ± 4.29^a

52.33 ± 28.65^ab

Ile

47.46 ± 9.29^a

290.31 ± 121.12^b

59.80 ± 11.22^a

37.20 ± 7.42^a

109.21 ± 15.21^a

Leu

72.55 ± 11.86^a

440.89 ± 166.35^b

88.96 ± 15.60^a

58.02 ± 10.82^a

138.27 ± 41.57^a

Lys

62.43 ± 11.01^a

135.83 ± 1.66^b

71.85 ± 14.99^a

55.50 ± 3.66^a

91.57 ± 28.20^a

Met

21.59 ± 4.40^a

68.44 ± 28.82^b

24.64 ± 5.93^a

25.20 ± 9.15^a

39.07 ± 0.62^ab

Nva

n.d.

40.08 ± 13.63

n.d.

Phe

95.33 ± 38.46^a

421.42 ± 56.81^a

325.09 ± 276.17^a

132.04 ± 48.79^a

300.36 ± 81.98^a

Pro

450.57 ± 106.69^ab

624.57 ± 63.12^a

400.83 ± 76.80^ab

313.10 ± 45.34^b

614.20 ± 237.51^ab

Ser

75.63 ± 12.49^a

243.24 ± 36.73^b

77.29 ± 9.98^a

59.12 ± 5.17^a

126.10 ± 47.49^a

Thr

50.64 ± 9.38^a

208.31 ± 45.25^b

52.45 ± 7.17^a

39.80 ± 4.42^a

101.53 ± 51.10^a

Trp

n.d.

Tyr

37.72 ± 15.45^a

221.64 ± 82.85^b

90.91 ± 38.34^a

51.27 ± 25.95^a

109.82 ± 16.94^ab

Val

58.00 ± 9.68^a

296.08 ± 86.44^b

68.71 ± 13.77^a

52.10 ± 3.56^a

107.82 ± 35.99^a

Total

1579.16 ± 299.20^a

4628.11 ± 918.98^b

1869.91 ± 451.09^a

1316.89 ± 186.77^a

2807.10 ± 1041.06^a

**Table 5.** Concentrations of organic acids, minerals, vitamins and enzyme activities in honeys
	Organic acid concentration (µg/g Honey), Mean ± SD
n.d. = not detected. Organic acids were quantified by GC (1), LC-MS (2), or specific assay kit (3).
Acetic acid¹	223.37 ± 13.08	94.03 ± 4.14	259.55 ± 2.81	243.85 ± 7.57	305.32 ± 3.74	245.37 ± 9.08	279.07 ± 15.06	256.49 ± 11.63
Citric acid²	56.01 ± 1.38	83.43 ± 0.80	79.61 ± 1.88	59.30 ± 0.41	131.51 ± 2.83	80.29 ± 0.29	253.27 ± 2.02	139.50 ± 0.13
Formic acid³	7.47 ± 2.65	7.70 ± 3.14	7.94 ± 2.89	8.88 ± 2.23	12.05 ± 3.55	8.23 ± 1.03	10.29 ± 2.55	7.82 ± 0.67
Gluconic acid²	3,171.56 ± 62.04	3,760.88 ± 19.96	3,163.84 ± 21.90	2,574.58 ± 34.40	3,810.69 ± 106.84	3,838.48 ± 83.97	6,430.92 ± 55.44	3,719.23 ± 82.36
Gluctaric acid²	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
Glycolic acid²	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
Lactic acid²	48.49 ± 4.10	45.38 ± 7.09	48.97 ± 4.95	22.35 ± 2.38	47.03 ± 2.55	82.14 ± 1.89	114.75 ± 5.74	47.91 ± 0.96
Maleic acid²	1.94 ± 0.20	2.36 ± 0.19	2.25 ± 0.09	1.52 ± 0.24	1.94 ± 0.28	2.16 ± 0.13	2.03 ± 0.19	1.48 ± 0.08
Malic acid²	54.90 ± 0.30	29.13 ± 0.71	78.44 ± 3.02	40.23 ± 1.37	69.14 ± 1.28	342.37 ± 6.50	75.75 ± 1.56	94.38 ± 1.61
Malonic acid²	46.56 ± 5.82	98.92 ± 6.64	69.53 ± 4.33	46.10 ± 8.96	63.09 ± 4.72	30.39 ± 3.43	74.64 ± 5.01	60.00 ± 3.65
Oxalic acid³	124.59 ± 0.83	155.32 ± 3.51	181.52 ± 0.63	193.70 ± 2.84	147.50 ± 0.32	149.69 ± 1.14	217.89 ± 1.67	152.23 ± 2.38
Propionic acid¹	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.
Succinic acid²	10.31 ± 0.67	10.15 ± 1.14	15.61 ± 0.68	9.12 ± 1.37	13.09 ± 0.38	35.81 ± 0.44	17.53 ± 1.89	16.98 ± 0.86
n.d. = not detected. Organic acids were quantified by GC (1), LC-MS (2), or specific assay kit (3).
Mineral contents (Mean ± SD)
Calcium	%	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03
Iron	ppm	<7	<7	<7	<7	<7	<7	7.05 ± 0.07	<7
Magnesium	%	<0.012	<0.012	<0.012	<0.012	<0.012	<0.012	<0.012	<0.012
Phosphorus	%	<0.014	<0.014	<0.014	<0.014	<0.014	<0.014	<0.014	<0.014
Potassium	%	0.03 ± 0.00	<0.03	<0.03	0.03 ± 0.00	0.03 ± 0.00	<0.03	0.05 ± 0.00	0.04 ± 0.00
Sodium	%	<0.013	<0.013	<0.013	<0.013	<0.013	<0.013	<0.013	<0.013
Zinc	ppm	<7	7.84 ± 1.19	<7	<7	<7	<7	7.44 ± 0.39	<7
Enzyme activity (Mean ± SD)
Amylase	U/100g	1.279 ± 0.000	1.525 ± 0.090	1.824 ± 0.104	2.825 ± 0.128	1.270 ± 0.052	1.215 ± 0.148	1.644 ± 0.130	2.616 ± 0.074
Diastase	Diastase unit	5.24 ± 0.20	7.07 ± 0.11	8.86 ± 0.32	7.75 ± 0.19	7.01 ± 0.09	4.79 ± 0.06	7.37 ± 0.06	6.82 ± 0.08
Glucose Oxidase	U/100	0.679 ± 0.013	0.685 ± 0.008	0.765 ± 0.008	0.965 ± 0.032	1.277 ± 0.008	1.174 ± 0.020	1.007 ± 0.022	0.918 ± 0.027
Catalase	U/100g	43.44 ± 1.59	171.9 ± 4.3	163.9 ± 13.2	53.80 ± 0.61	157.8 ± 1.7	39.59 ± 4.38	156.2 ±7.2	91.34 ± 2.05
Invertase	mU/100g	16.08 ± 0.50	28.20 ± 2.09	26.59 ± 0.42	19.50 ± 0.714	34.40 ± 1.83	25.37 ± 1.31	53.87 ± 4.11	24.64 ± 0.87
Acid Phosphatase	mg P/100g /24 h	52.13 ± 3.90	55.49 ± 1.64	58.78 ± 2.11	60.04 ± 1.55	57.96 ± 2.09	60.23 ± 0.44	50.93 ± 1.16	58.40 ± 2.20
n.d. = not detected. Organic acids were quantified by GC (1), LC-MS (2), or specific assay kit (3).
Riboflavin (B2)	0.054 ± 0.079^ab	0.187 ± 0.010^a	0.022 ± 0.025^b	0.031 ± 0.045^b	0.098 ± 0.092^ab
Nicotinic acid (B3)	0.228 ± 0.048^a	0.849 ± 0.108^b	0.381 ± 0.015^cd	0.250 ± 0.040^ac	0.437 ± 0.059^d
Pantothenic acid (B5)	0.045 ± 0.019^a	0.162 ± 0.069^a	0.154 ± 0.079^a	0.071 ± 0.041^a	0.183 ± 0.108^a
Pyridoxine (B6)	0.011 ± 0.003^a	0.037 ± 0.015^ab	0.064 ± 0.021^b	0.017 ± 0.005^ab	0.073 ± 0.044^b
Ascorbic acid	n.d.	n.d.	n.d.	n.d.	n.d.

Table 5. Concentrations of organic acids, minerals, vitamins and enzyme activities in honeys

Organic acid concentration (µg/g Honey), Mean ± SD

Alfalfa1

Clover1

Clover2

Clover3

Golden1

Orange1

Wildflower1

Wildflower2

n.d. = not detected. Organic acids were quantified by GC (1), LC-MS (2), or specific assay kit (3).

Acetic acid¹

223.37 ± 13.08

94.03 ± 4.14

259.55 ± 2.81

243.85 ± 7.57

305.32 ± 3.74

245.37 ± 9.08

279.07 ± 15.06

256.49 ± 11.63

Citric acid²

56.01 ± 1.38

83.43 ± 0.80

79.61 ± 1.88

59.30 ± 0.41

131.51 ± 2.83

80.29 ± 0.29

253.27 ± 2.02

139.50 ± 0.13

Formic acid³

7.47 ± 2.65

7.70 ± 3.14

7.94 ± 2.89

8.88 ± 2.23

12.05 ± 3.55

8.23 ± 1.03

10.29 ± 2.55

7.82 ± 0.67

Gluconic acid²

3,171.56 ± 62.04

3,760.88 ± 19.96

3,163.84 ± 21.90

2,574.58 ± 34.40

3,810.69 ± 106.84

3,838.48 ± 83.97

6,430.92 ± 55.44

3,719.23 ± 82.36

Gluctaric acid²

n.d.

Glycolic acid²

n.d.

Lactic acid²

48.49 ± 4.10

45.38 ± 7.09

48.97 ± 4.95

22.35 ± 2.38

47.03 ± 2.55

82.14 ± 1.89

114.75 ± 5.74

47.91 ± 0.96

Maleic acid²

1.94 ± 0.20

2.36 ± 0.19

2.25 ± 0.09

1.52 ± 0.24

1.94 ± 0.28

2.16 ± 0.13

2.03 ± 0.19

1.48 ± 0.08

Malic acid²

54.90 ± 0.30

29.13 ± 0.71

78.44 ± 3.02

40.23 ± 1.37

69.14 ± 1.28

342.37 ± 6.50

75.75 ± 1.56

94.38 ± 1.61

Malonic acid²

46.56 ± 5.82

98.92 ± 6.64

69.53 ± 4.33

46.10 ± 8.96

63.09 ± 4.72

30.39 ± 3.43

74.64 ± 5.01

60.00 ± 3.65

Oxalic acid³

124.59 ± 0.83

155.32 ± 3.51

181.52 ± 0.63

193.70 ± 2.84

147.50 ± 0.32

149.69 ± 1.14

217.89 ± 1.67

152.23 ± 2.38

Propionic acid¹

n.d.

Succinic acid²

10.31 ± 0.67

10.15 ± 1.14

15.61 ± 0.68

9.12 ± 1.37

13.09 ± 0.38

35.81 ± 0.44

17.53 ± 1.89

16.98 ± 0.86

Unit

Alfalfa1

Clover1

Clover2

Clover3

Golden1

Orange1

Wildflower1

Wildflower2

n.d. = not detected. Organic acids were quantified by GC (1), LC-MS (2), or specific assay kit (3).

Mineral contents (Mean ± SD)

Calcium

<0.03

Iron

ppm

7.05 ± 0.07

Magnesium

<0.012

Phosphorus

<0.014

Potassium

0.03 ± 0.00

<0.03

0.03 ± 0.00

<0.03

0.05 ± 0.00

0.04 ± 0.00

Sodium

<0.013

Zinc

ppm

7.84 ± 1.19

7.44 ± 0.39

Enzyme activity (Mean ± SD)

Amylase

U/100g

1.279 ± 0.000

1.525 ± 0.090

1.824 ± 0.104

2.825 ± 0.128

1.270 ± 0.052

1.215 ± 0.148

1.644 ± 0.130

2.616 ± 0.074

Diastase

Diastase unit

5.24 ± 0.20

7.07 ± 0.11

8.86 ± 0.32

7.75 ± 0.19

7.01 ± 0.09

4.79 ± 0.06

7.37 ± 0.06

6.82 ± 0.08

Glucose Oxidase

U/100

0.679 ± 0.013

0.685 ± 0.008

0.765 ± 0.008

0.965 ± 0.032

1.277 ± 0.008

1.174 ± 0.020

1.007 ± 0.022

0.918 ± 0.027

Catalase

U/100g

43.44 ± 1.59

171.9 ± 4.3

163.9 ± 13.2

53.80 ± 0.61

157.8 ± 1.7

39.59 ± 4.38

156.2 ±7.2

91.34 ± 2.05

Invertase

mU/100g

16.08 ± 0.50

28.20 ± 2.09

26.59 ± 0.42

19.50 ± 0.714

34.40 ± 1.83

25.37 ± 1.31

53.87 ± 4.11

24.64 ± 0.87

Acid Phosphatase

mg P/100g /24 h

52.13 ± 3.90

55.49 ± 1.64

58.78 ± 2.11

60.04 ± 1.55

57.96 ± 2.09

60.23 ± 0.44

50.93 ± 1.16

58.40 ± 2.20

Vitamins (µg/g Honey), Mean ± SD

Alfalfa

Buckwheat

Clover

Orange

Wildflower

n.d. = not detected. Organic acids were quantified by GC (1), LC-MS (2), or specific assay kit (3).

Riboflavin (B2)

0.054 ± 0.079^ab

0.187 ± 0.010^a

0.022 ± 0.025^b

0.031 ± 0.045^b

0.098 ± 0.092^ab

Nicotinic acid (B3)

0.228 ± 0.048^a

0.849 ± 0.108^b

0.381 ± 0.015^cd

0.250 ± 0.040^ac

0.437 ± 0.059^d

Pantothenic acid (B5)

0.045 ± 0.019^a

0.162 ± 0.069^a

0.154 ± 0.079^a

0.071 ± 0.041^a

0.183 ± 0.108^a

Pyridoxine (B6)

0.011 ± 0.003^a

0.037 ± 0.015^ab

0.064 ± 0.021^b

0.017 ± 0.005^ab

0.073 ± 0.044^b

Ascorbic acid

n.d.

**Table 6.** Concentrations of individual carbohydrates and sugar contents of honeys
	Carbohydrate concentration (g/100g Honey), Mean ± SD
n.t. = not tested; n.d. = not detected.
Fructose	38.48 ± 0.57	37.84 ± 1.55	40.36 ± 1.89	40.69 ± 1.60	38.25 ± 0.41	39.44 ± 1.15	36.60 ± 1.28	39.66 ± 1.70	40.2 ± 1.87	41.53 ± 1.90	37.51 ± 0.60	37.47 ± 1.53
Glucose	34.57 ± 0.25	32.8 ± 1.32	32.03 ± 0.95	36.94 ± 1.62	31.78 ± 0.34	33.50 ± 0.89	32.49 ± 0.90	36.08 ±2.35	34.37 ± 0.88	36.98 ± 0.82	33.62 ± 0.33	33.56 ± 1.04
Sucrose	0.72 ± 0.01	1.1 ± 0.05	0.58 ± 0.02	0.13 ± 0.003	0.68 ± 0.02	0.16 ± 0.003	0.42 ± 0.04	0.17 ± 0.002	0.26 ± 0.02	0.11 ± 0.01	0.61 ± 0.08	0.12 ± 0.01
Trehalose	n.t.	0.06 ± 0	0.42 ± 0.03	n.t.	n.t.	n.t.	n.t.	n.t.	0.15 ± 0.01	n.t.	0.1 ± 0	n.t.
Kojibiose	n.t.	1.47 ± 0.02	1.68 ± 0.03	n.t.	n.t.	n.t.	n.t.	n.t.	1.58 ± 0.02	n.t.	1.57 ± 0.02	n.t.
Turanose	n.t.	1.42 ± 0.03	1.53 ± 0.03	1.57 ± 0.06	n.d.	2.36 ± 0.09	n.d.	1.99 ± 0.04	1.46 ± 0.07	1.31 ± 0.07	1.46 ± 0.05	n.t.
Maltose	n.t.	2.47 ± 0.03	2.2 ± 0.03	1.41 ± 0.06	n.d.	1.39 ± 0.04	n.d.	1.12 ± 0.01	1.81 ± 0.07	1.31 ± 0.04	1.45 ± 0.04	n.t.
Isomaltose	n.t.	0.51 ± 0.01	0.55 ± 0.01	0.56 ± 0.02	n.d.	0.79 ± 0.03	n.d.	0.56 ± 0.01	0.54 ± 0.03	0.41 ± 0.02	0.53 ± 0.01	n.t.
Palatinose (isomaltulose)	n.t.	0.15 ± 0.01	0.15 ± 0.01	0.24 ± 0.007	n.d.	0.43 ± 0.03	n.d.	0.33 ± 0.01	0.23 ± 0.02	0.17 ± 0.02	0.22 ± 0.01	n.t.
Nigerose	n.t.	0.28 ± 0.01	0.31 ± 0.01	0.31 ± 0.02	n.d.	0.39 ± 0.02	n.d.	0.29 ± 0.01	0.30 ± 0.01	0.23 ± 0.01	0.25 ± 0.01	n.t.
Melezitose	n.t.	2.35 ± 0.22	1.29 ± 0.1	n.d.	n.d.	n.d.	n.d.	n.d.	1.81 ± 0.31	n.d.	1.29 ± 0.1	n.d.
Isomaltotriose	n.t.	0.02 ± 0.01	0.01 ± 0	n.d.	n.d.	n.d.	n.d.	n.d.	0.03 ± 0	n.d.	0.01 ± 0	n.d.
Maltotriose	n.t.	0.32 ± 0.01	0.48 ± 0.01	n.d.	n.d.	n.d.	n.d.	n.d.	0.37 ± 0.01	n.d.	0.48 ± 0.01	n.d.
Total sugars	78.52 ± 2.28	81.22 ± 4.77	81.14 ± 2.98	79.30 ± 2.80	78.34 ± 2.27	80.57 ± 0.90	79.30 ± 5.23	81.81 ± 2.21	81.78 ± 2.79	80.67 ± 1.67	81.87 ± 2.2	78.94 ± 2.52
Moisture	17.73 ± 0.42	16.67 ± 1.39	15.53 ± 0.64	15.27 ± 0.47	17.93 ± 0.46	15.33 ± 0.05	17 ± 0.001	15.57 ± 0.19	16.13 ± 1.43	15.76 ± 0.51	16.8 ± 0	19.2 ± 0.72

Table 6. Concentrations of individual carbohydrates and sugar contents of honeys

Carbohydrate concentration (g/100g Honey), Mean ± SD

Clover 1

Clover 2

Clover 3

Clover 4

Orange 1

Orange 2

Alfalfa 1

Alfalfa 2

Wildflower 1

Wildflower 2

Golden

Buckwheat

n.t. = not tested; n.d. = not detected.

Fructose

38.48 ± 0.57

37.84 ± 1.55

40.36 ± 1.89

40.69 ± 1.60

38.25 ± 0.41

39.44 ± 1.15

36.60 ± 1.28

39.66 ± 1.70

40.2 ± 1.87

41.53 ± 1.90

37.51 ± 0.60

37.47 ± 1.53

Glucose

34.57 ± 0.25

32.8 ± 1.32

32.03 ± 0.95

36.94 ± 1.62

31.78 ± 0.34

33.50 ± 0.89

32.49 ± 0.90

36.08 ±2.35

34.37 ± 0.88

36.98 ± 0.82

33.62 ± 0.33

33.56 ± 1.04

Sucrose

0.72 ± 0.01

1.1 ± 0.05

0.58 ± 0.02

0.13 ± 0.003

0.68 ± 0.02

0.16 ± 0.003

0.42 ± 0.04

0.17 ± 0.002

0.26 ± 0.02

0.11 ± 0.01

0.61 ± 0.08

0.12 ± 0.01

Trehalose

n.t.

0.06 ± 0

0.42 ± 0.03

n.t.

0.15 ± 0.01

n.t.

0.1 ± 0

n.t.

Kojibiose

n.t.

1.47 ± 0.02

1.68 ± 0.03

n.t.

1.58 ± 0.02

n.t.

1.57 ± 0.02

n.t.

Turanose

n.t.

1.42 ± 0.03

1.53 ± 0.03

1.57 ± 0.06

n.d.

2.36 ± 0.09

n.d.

1.99 ± 0.04

1.46 ± 0.07

1.31 ± 0.07

1.46 ± 0.05

n.t.

Maltose

n.t.

2.47 ± 0.03

2.2 ± 0.03

1.41 ± 0.06

n.d.

1.39 ± 0.04

n.d.

1.12 ± 0.01

1.81 ± 0.07

1.31 ± 0.04

1.45 ± 0.04

n.t.

Isomaltose

n.t.

0.51 ± 0.01

0.55 ± 0.01

0.56 ± 0.02

n.d.

0.79 ± 0.03

n.d.

0.56 ± 0.01

0.54 ± 0.03

0.41 ± 0.02

0.53 ± 0.01

n.t.

Palatinose (isomaltulose)

n.t.

0.15 ± 0.01

0.24 ± 0.007

n.d.

0.43 ± 0.03

n.d.

0.33 ± 0.01

0.23 ± 0.02

0.17 ± 0.02

0.22 ± 0.01

n.t.

Nigerose

n.t.

0.28 ± 0.01

0.31 ± 0.01

0.31 ± 0.02

n.d.

0.39 ± 0.02

n.d.

0.29 ± 0.01

0.30 ± 0.01

0.23 ± 0.01

0.25 ± 0.01

n.t.

Melezitose

n.t.

2.35 ± 0.22

1.29 ± 0.1

n.d.

1.81 ± 0.31

n.d.

1.29 ± 0.1

n.d.

Isomaltotriose

n.t.

0.02 ± 0.01

0.01 ± 0

n.d.

0.03 ± 0

n.d.

0.01 ± 0

n.d.

Maltotriose

n.t.

0.32 ± 0.01

0.48 ± 0.01

n.d.

0.37 ± 0.01

n.d.

0.48 ± 0.01

n.d.

Total sugars

78.52 ± 2.28

81.22 ± 4.77

81.14 ± 2.98

79.30 ± 2.80

78.34 ± 2.27

80.57 ± 0.90

79.30 ± 5.23

81.81 ± 2.21

81.78 ± 2.79

80.67 ± 1.67

81.87 ± 2.2

78.94 ± 2.52

Moisture

17.73 ± 0.42

16.67 ± 1.39

15.53 ± 0.64

15.27 ± 0.47

17.93 ± 0.46

15.33 ± 0.05

17 ± 0.001

15.57 ± 0.19

16.13 ± 1.43

15.76 ± 0.51

16.8 ± 0

19.2 ± 0.72