Table 2.
Effect of impregnation and steam explosion condition on color values of P. densiflora

Severity factor (Ro)	Color values
	L1)	a2)	b3)	whiteness
	Untreated	77.7 ± 0.9 a4)	6.1 ± 0.5 f	26.8 ± 0.6 a	-
Non-impregnation
3.68	51.1 ± 0.5 d	8.6 ± 0.1 de	20.0 ± 0.1 ef	28.8 e
4.16	47.5 ± 0.3 e	10.1 ± 0.2 c	22.9 ± 0.2 b	32.0 d
4.53	44.7 ± 0.3 f	10.6 ± 0.1 b	21.7 ± 0.3 c	35.0 c
4.79	38.3 ± 0.6 h	11.1 ± 0.2 a	20.8 ± 0.5 d	41.4 a
Water-impregnation
3.68	61.6 ± 0.7 b	6.5 ± 0.2 f	19.5 ± 0.3 f	18.8 h
4.16	53.7 ± 0.6 c	8.5 ± 0.0 e	21.8 ± 0.4 c	25.9 g
4.53	51.4 ± 0.2 d	8.9 ± 0.1 d	21.6 ± 0.3 c	28.2 f
4.79	42.4 ± 0.1 g	9.9 ± 0.1 c	20.4 ± 0.3 de	37.3 b

L : lightness
a : green–red coordinate
b : blue–yellow coordinate
In each column, values with different letters indicate statistically significant differences(p<0.05) by Duncan’s test