Chemical Composition and Antioxidant Properties of Five White Onion (Allium cepa L.) Landraces

Table 3

Organic acids (mg/100 g fw; mean ± SD), sugars (g/100 g fw; mean ± SD) content, and pungency (mol/g fresh weight) of Bianca di Pompei onion landraces.

	Febbrarese	Marzatica	Aprilatica	Maggiaiola	Giugnese
Organic acids
Malic acid	60.43 ± 6.53	66.33 ± 6.61	61.85 ± 4.50	57.61 ± 3.34	78.94 ± 2.10
Citric acid	63.32 ± 5.90	57.05 ± 3.24	54.55 ± 5.43	34.46 ± 5.38	19.70 ± 3.95
Tartaric acid	13.93 ± 2.75	6.10 ± 1.21	16.15 ± 1.25	25.88 ± 4.57	12.02 ± 2.85
Oxalic acid	30.43 ± 2.97	19.93 ± 1.51	13.60 ± 1.41	12.21 ± 1.90	10.68 ± 2.92
Ascorbic acid	4.63 ± 0.85	4.85 ± 0.15	21.65 ± 2.80	17.69 ± 1.96	14.80 ± 1.73
Succinic acid	11.55 ± 1.04	9.28 ± 2.72	19.40 ± 0.89	23.35 ± 2.21	14.34 ± 0.82
Pyruvic acid	1.07 ± 0.44	1.18 ± 0.66	0.35 ± 0.09	0.76 ± 0.21	0.50 ± 0.10
Total	185.36 ± 52.83	164.72 ± 30.07	187.55 ± 55.79	171.96 ± 52.16	150.98 ± 21.79
Pungency (EPY)	9.31 ± 0.97	10.01 ± 0.31	14.34 ± 0.13	13.00 ± 0.84	12.53 ± 0.27
Soluble sugars
Fructose	1.74 ± 0.42	1.66 ± 0.62	2.11 ± 0.23	2.00 ± 0.60	2.26 ± 0.70
Glucose	1.09 ± 0.18	0.88 ± 0.43	1.97 ± 0.09	1.79 ± 0.54	2.00 ± 0.27
Sucrose	0.90 ± 0.11	0.81 ± 0.21	1.76 ± 0.36	1.04 ± 0.27	1.21 ± 0.24
Total	3.73 ± 0.64	3.35 ± 1.16	5.83 ± 0.67	4.84 ± 1.32	5.46 ± 1.09

Different letters (a, b, c, etc.) correspond to significant differences () among onion landraces.