Physicochemical properties of eleven monofloral honey samples produced in Morocco

Figures & data

Figure 1. Production area of analysed honeys.

Table 1. Moisture, water activity, colour, diastase and proline data obtained from honey samples.

	Moisture (g/100g)	Water activity	HMF (mg /Kg)	Color (pfund scale mm)	Diastase (°Gothe)	Proline (mg/Kg)
Acacia	16.45 ± 0.39^bcd	0.535 ± 0.02^a	68.92 ± 0.41	107.12 ± 2.31	23.81 ± 0.45	900.91 ± 13.36^a
Carob	17.15 ± 0.19^cde	0.548 ± 0.01^c	17.88 ± 0.49	149.52 ± 2.81	7.40 ± 0.44	775.03 ± 9.44
Eucalyptus	19.54 ± 0.36^g	0.574 ± 0.02^e	32.77 ± 0.42	71.37 ± 1.27	19.11 ± 0.49	1207.55 ± 13.97
Harmal	14.55 ± 0.26^a	0.495 ± 0.02	25.06 ± 0.59	126.18 ± 2.55	29.29 ± 0.58	531.32 ± 10.45
Jujube	18.55 ± 0.32^fg	0.564 ± 0.02^d	20.95 ± 0.64	51.44 ± 1.62	22.30 ± 0.57	607.78 ± 10.83
Lavender	16.16 ± 0.31^bc	0.538 ± 0.02^ab	26.95 ± 0.44	45.96 ± 1.07^a	10.60 ± 0.42^a	1042.61 ± 14.14
Orange	17.92 ± 0.29^ef	0.561 ± 0.03^d	11.24 ± 0.52	13.33 ± 0.98	25.36 ± 0.75	842.12 ± 11.30
Reseda	20.99 ± 0.75	0.577 ± 0.02^e	42.31 ± 0.62	19.59 ± 0.95	11.46 ± 0.47^a	667.16 ± 10.02
Rosemary	15.43 ± 0.33^ab	0.525 ± 0.03	8.30 ± 0.45	41.49 ± 1.22^a	8.88 ± 0.37	961.21 ± 12.29
Spurge	14.78 ± 0.32^a	0.489 ± 0.02	39.39 ± 0.48	60.97 ± 1.72	14.40 ± 0.40	441.67 ± 11.62
Thyme	17.33 ± 0.39^de	0.544 ± 0.02^bc	56.98 ± 0.45	88.55 ± 1.51	16.61 ± 0.48	877.41 ± 12.87^a

Values are mean of triplicate determinations (n = 3) ± standard deviation. The results are statistically significant at p < 0.05; in the same column, the values with different letters are significantly different using post hoc Fisher's PLSD test (p < 0.001).

Table 2. Free acidity, pH, lactone acidity, and total acidity results obtained from honey samples.

	pH	Total acidity (meq/kg)	Free acidity (meq/kg)	Lactonic acidity (meq/kg)
Acacia	4.62 ± 0.02	24.57 ± 0.76^ab	10.93 ± 0.54	13.64 ± 0.30
Carob	4.04 ± 0.02	32.14 ± 0.87^d	25.94 ± 0.53	6.20 ± 0.36^ab
Eucalyptus	4.46 ± 0.01	24.54 ± 0.82^ab	12.84 ± 0.64	11.70 ± 0.36
Harmal	4.21 ± 0.02	26.84 ± 0.19^bc	17.46 ± 0.47^a	9.37 ± 0.34^e
Jujube	4.13 ± 0.02	27.00 ± 0.78 ^c	22.83 ± 0.69^c	4.17 ± 0.34
Lavender	4.90 ± 0.01	23.55 ± 0.98^a	15.90 ± 0.82^a	7.65 ± 0.28^cd
Orange	3.74 ± 0.02	33.99 ± 1.04^de	28.37 ± 0.81	5.61 ± 0.28^a
Reseda	3.54 ± 0.02^a	43.53 ± 0.90	36.67 ± 0.75	6.86 ± 0.30^bc
Rosemary	3.94 ± 0.02	35.67 ± 0.88^e	20.94 ± 0.51^b	14.73 ± 0.43
Spurge	3.83 ± 0.02	32.58 ± 0.49^d	22.15 ± 0.59^bc	10.43 ± 0.28
Thyme	3.59 ± 0.03^a	40.69 ± 0.57	32.21 ± 0.67	8.49 ± 0.35^de

Values are mean of triplicate determinations (n = 3)±standard deviation. The results are statistically significant at p < 0.05; in the same column, the values with different letters are significantly different using post hoc Fisher's PLSD test (p < 0.001).

Figure 2. Chromatogram of organic acid found in eucalyptus honey. Peak numbers: oxalic acid (1); malic acid (2); lactic acid (3); citric acid (4); succinic acid (5); fumaric acid (6).

Table 3. Sugar and organic acids content of honey samples.

	Citric acid^a	Fumaric acid^a	Lactic acid^a	Malic acid^a	Oxalic acid^a	Succinic acid^a	Glucose^b	Fructose^b	Sucrose^b
Acacia	ND	2.63 ± 0.02	162.63 ± 0.97	112.78 ± 0.56	32.46 ± 0.55	57.46 ± 0.72	380.33 ± 5.14	401.86 ± 5.24^b^c	1.96 ± 0.06
Carob	61.72 ± 0.67	1.14 ± 0.02	179.38 ± 1.35	119.12 ± 0.83	82.19 ± 0.50	37.89 ± 0.62	346.45 ± 3.67^b^c	351.29 ± 6.04^a	1.55 ± 0.06
Eucalyptus	81.06 ± 0.72	5.93 ± 0.03	130.27 ± 1.31	87.58 ± 0.68	69.46 ± 0.62	70.16 ± 0.82	256.82 ± 3.58	391.40 ± 3.96^b	0.92 ± 0.07^a
Harmal	143.86 ± 0.76	3.55 ± 0.03	124.55 ± 1.03	60.39 ± 0.71	139.26 ± 0.70	ND	358.11 ± 3.94^c	487.03 ± 4.40	1.26 ± 0.05^cd
Jujube	128.97 ± 0.78	0.93 ± 0.02	140.39 ± 1.46	142.48 ± 0.74	47.77 ± 0.65	53.14 ± 0.79	337.42 ± 4.33^b	463.70 ± 4.15	1.36 ± 0.06^d
Lavender	50.46 ± 0.89	0.26 ± 0.06	149.74 ± 1.96	160.28 ± 0.64	22.83 ± 0.54	ND	297.41 ± 4.63^a	352.90 ± 6.60^a	1.16 ± 0.04^b^c
Orange	172.71 ± 0.73	4.66 ± 0.04	103.99 ± 1.33	168.97 ± 0.72	95.19 ± 0.75	157.35 ± 0.60	315.48 ± 3.67	438.90 ± 3.29	2.35 ± 0.06
Reseda	298.48 ± 0.90	3.23 ± 0.02	108.51 ± 1.51^a	180.19 ± 0.84	53.91 ± 0.66	170.63 ± 0.72	236.03 ± 4.57	371.11 ± 5.44	ND
Rosemary	152.66 ± 0.65	0.54 ± 0.02	111.51 ± 1.07^a	122.10 ± 0.67	111.58 ± 0.61	98.30 ± 0.77	274.47 ± 5.22	339.55 ± 6.65^a	ND
Spurge	105.71 ± 0.62	0.68 ± 0.01	134.47 ± 1.43	105.64 ± 0.75	37.88 ± 0.78	150.49 ± 0.61	287.33 ± 4.96^a	397.14 ± 4.59^b	1.04 ± 0.07^a^b
Thyme	204.30 ± 0.76	1.94 ± 0.02	119.65 ± 1.39	129.35 ± 0.76	177.04 ± 0.51	190.06 ± 0.79	359.10 ± 4.06^c	415.60 ± 5.00^c	ND

Values are mean of triplicate determinations (n = 3)±standard deviation. The results are statistically significant at p < 0.05; in the same column, the values with different letters are significantly different using post hoc Fisher's PLSD test (p < 0.001).

^amg/kg.

^bg/kg.

Figure 3. Chromatogram of sugar found in orange honey. Peak numbers: fructose (1); glucose (2); sucrose (3).

Table 4. Electrical conductivity, ash and mineral content of honey samples.

	E. conductivity μS cm^–1	Ash (g/kg)	Cu (mg/kg)	Mn (mg/kg)	Fe (mg/kg)	Zn (mg/kg)	Ca (mg/kg)	Mg (mg/kg)	K (mg/kg)	Na (mg/kg)
Acacia	653.42 ± 1.22	4.90 ± 0.13^bc	1.39 ± 0.07^e	2.78 ± 0.24^a	15.01 ± 0.12	4.56 ± 0.32^bc	154.14 ± 2.96	86.58 ± 3.18	1374.67 ± 20.36	115.46 ± 2.34
Carob	780.52 ± 1.02	5.70 ± 0.10^c	0.74 ± 0.04^ab	4.41 ± 0.23^c	9.66 ± 0.46^c	5.25 ± 0.15^cd	242.36 ± 4.06	113.60 ± 2.62	1487.71 ± 19.55	296.68 ± 4.41
Eucalyptus	623.29 ± 0.99	4.73 ± 0.12^b	0.85 ± 0.04^bc	6.70 ± 0.25^d	9.29 ± 0.46^c	3.13 ± 0.17^a	89.34 ± 2.43^c	68.32 ± 2.54^c	1023.78 ± 20.12	159.66 ± 5.55
Harmal	824.45 ± 1.24	5.20 ± 0.15	0.96 ± 0.04^cd	8.54 ± 0.36	10.88 ± 0.64	6.87 ± 0.28^f	184.11 ± 3.42	97.18 ± 2.75	1244.39 ± 20.44	252.32 ± 4.42
Jujube	322.80 ± 1.20	3.30 ± 0.10	2.33 ± 0.07	3.08 ± 0.19^ab	5.64 ± 0.31^b	4.33 ± 0.26^b	75.48 ± 2.20^a	27.03 ± 2.95^a	562.66 ± 5.04	97.70 ± 2.30^b
Lavender	488.18 ± 0.95	4.00 ± 0.10^a	0.64 ± 0.06^a	5.31 ± 0.23	4.35 ± 0.26^a	5.87 ± 0.24^de	86.88 ± 1.98^c	55.17 ± 2.62	788.53 ± 8.47	88.32 ± 4.59^b
Orange	208.11 ± 0.68	2.33 ± 0.06	1.10 ± 0.04^d	9.93 ± 0.35^e	2.44 ± 0.29	9.47 ± 0.42	44.39 ± 0.90	31.94 ± 2.05^ab	311.57 ± 7.11	45.71 ± 1.72^a
Reseda	137.12 ± 0.73	1.70 ± 0.10	0.59 ± 0.03^a	9.33 ± 0.31^e	3.73 ± 0.25^a	1.16 ± 0.03	84.83 ± 1.63^bc	36.39 ± 2.69^b	263.40 ± 5.05	54.71 ± 3.15^a
Rosemary	466.23 ± 0.97	3.63 ± 0.12	1.30 ± 0.09^e	2.35 ± 0.16^a	5.79 ± 0.16^b	4.97 ± 0.18^bc	115.03 ± 2.54	69.73 ± 3.08^c	647.97 ± 7.33	66.62 ± 2.47
Spurge	531.65 ± 1.03	4.13 ± 0.06^a	1.68 ± 0.07	7.37 ± 0.29^d	7.88 ± 0.36	6.42 ± 0.27^ef	97.52 ± 2.43	73.36 ± 2.63^c	874.94 ± 14.77	172.65 ± 3.26
Thyme	593.38 ± 1.19	4.27 ± 0.12^a	1.45 ± 0.07^e	3.64 ± 0.22^bc	16.62 ± 0.36	2.59 ± 0.15^a	78.21 ± 2.02^ab	36.09 ± 2.81^b	1163.45 ± 11.95	131.77 ± 3.37

Values are mean of triplicate determinations (n = 3)±standard deviation. The results are statistically significant at p < 0.05; in the same column, the values with different letters are significantly different using post hoc Fisher's PLSD test (p < 0.001).

Table 5. Toxic metals content of honey samples.

	Al	Cd	Pb	Ni
Acacia	10.11 ± 0.16^a	ND	ND	0.010 ± 0.01^a
Carob	4.40 ± 0.12	0.019 ± 0.001^b	0.08 ± 0.009	0.163 ± 0.03^f
Eucalyptus	7.91 ± 0.09	0.042 ± 0.003	0.25 ± 0.02	0.33 ± 0.03
Harmal	9.19 ± 0.15	ND	ND	0.093 ± 0.01^de
Jujube	11.89 ± 0.13	ND	ND	0.062 ± 0.01^bcd
Lavender	9.77 ± 0.12^b	ND	0.047 ± 0.01^b	0.137 ± 0.01^ef
Orange	12.90 ± 0.14	0.023 ± 0.003^b	0.036 ± 0.005^ab	0.085 ± 0.01^cd
Reseda	6.82 ± 0.13	ND	ND	0.039 ± 0.01^abc
Rosemary	8.69 ± 0.16	ND	0.14 ± 0.01	0.017 ± 0.006^ab
Spurge	3.44 ± 0.16	0.010 ± 0.001^a	0.013 ± 0.002^a	ND
Thyme	7.49 ± 0.15	0.008 ± 0.002^a	0.19 ± 0.01	0.186 ± 0.02^f

Values are mean of triplicate determinations (n = 3)±standard deviation. The results are statistically significant at p < 0.05; in the same column, the values with different letters are significantly different using post hoc Fisher's PLSD test (p < 0.001).