Skip to main content


Official Journal of the Japan Wood Research Society

Journal of Wood Science Cover Image

Table 2 In vitro model of ellagitannins chemistry during duraminisation process: influence of oxidation (1 vs. 2)1; influence of association of oxidised ellagitannins and polysaccharides (a vs. b)2 (initial extract from acetone/water (7/3, v/v) extraction of Q. robur outer heartwood)

From: Origin and characterisation of the extractable colour of oak heartwood used for ageing spirits

 Dry extract colourChromatic values
%O.D 420 nmL*a*b*C*h*
1—Fresh extract
 b—EP complex29.60.3532.95.517.918.71.3
2—Oxidised extract1
 b—EP complex72.40.6225.13.79.910.51.2
  1. 130 days at 20 °C with air exposition in solution: 12% vol. EtOH, 5 g/L tartaric acid, pH 3.5, NaF, 100 mg/L
  2. 2a: soluble in EtOH/water 9/1, b: insoluble in EtHOH/water 9/1