Table 3. Effect of cooking methods on sweetness of sweetpotato storage roots.

Variety	Raw sweetpotatoes (%)	Baking (fold)	Boiling (fold)	Steaming (fold)
Jinyu	0.77 ± 0.03 d (100)	6.50 ± 0.12 c (8.44)	3.57 ± 0.09 c (4.64)	4.40 ± 0.15 d (5.71)
Xinxiang	0.62 ± 0.05 c (80.5)	2.60 ± 0.07 b (4.19)	1.75 ± 0.12 a (2.82)	4.03 ± 0.05 c (6.50)
Yuzishu263	0.43 ± 0.02 a (55.8)	2.90 ± 0.16 b (6.74)	2.37 ± 0.05 b (5.51)	3.60 ± 0.12 b (8.37)
Zimei	0.50 ± 0.03 b (64.9)	1.80 ± 0.06 a (3.60)	4.12 ± 0.21 d (8.24)	2.74 ± 0.05 a (5.48)

Note: The numbers in the table represent the index of sweetness of raw sweetpotatoes and those under different cooking conditions followed by the fold of sweetness in the cooked sweetpotatoes relative to those in raw sweetpotatoes. Different lower-case letters besides the numbers in the table represent significant difference at 0.05 levels among all cultivars under the same cooking treatment.