Table 4.
Extraction Yields and Extract pH Values with Varying Amounts of NaOH

Liquor ratio	NaOH (g)	Extraction time (min)	Extraction yield (%)	pH
5	0.125	60	56.99	N.D
	0.17		60.91	11.9
	0.18		62.26	12.1

N.D.: Not determined, Radiata pine bark: 1 g (o.d)