Effect of Preservation Methods on Physicochemical Quality, Phenolic Content, and Antioxidant Activity of Stevia Leaves

Table 1

Proximate composition (g/100 g) and mineral elements (mg/kg dm) of commercial, freeze-dried, and gamma-irradiated stevia.

	Commercial (C)	Freeze-dried (FD)	Gamma-irradiated (GI)
			0.5 kGy	1 kGy	2 kGy
Moisture content	9.93 ± 0.9^a	6.86 ± 0.2^c	8.99 ± 0.9^b	9.22 ± 0.9^b	8.89 ± 1^b
Fat content	3.41 ± 0.04^a	2.34 ± 0.03^b	2.13 ± 0.03^c	1.96 ± 0.02^c	1.63 ± 0.02^c
Ash content	8.72 ± 1^a	9.12 ± 0.9^a	8.49 ± 0.8^a	8.58 ± 0.8^a	9.36 ± 1^a
Mineral content (ppm) K	4458 ± 38^c	9000 ± 50^a	7819 ± 53^b	7796 ± 37^b	7633 ± 56^b
Ca	8360 ± 48^a	9104 ± 55^a	9614 ± 55^a	8943 ± 52^a	8940 ± 53^a
P	1031 ± 41^a	1091 ± 43^a	1041 ± 41^a	1024 ± 42^a	1038 ± 46^a
Mn	304 ± 18^b	402 ± 21^a	483 ± 21^a	443 ± 19^a	431 ± 25^a
Fe	541 ± 17^b	515 ± 15^b	954 ± 22^a	950 ± 17^a	945 ± 24^a
Zn	36 ± 2^a	34 ± 2^a	39 ± 2^a	37 ± 2^a	32 ± 2^a

The results are presented as the mean ± standard deviation (SD; n = 3). Different letters in the same row indicate significant differences at  ≤ 0.05.