US 11,937,626 B2
Method for whitening tobacco
Bas Castelijn, Groningen (NL); Lars Olov Sundvall, Domsjö (SE); Richard Svensson, Vårgårda (SE); and David Neil McClanahan, Winston-Salem, NC (US)
Assigned to Nicoventures Trading Limited, London (GB)
Filed by Nicoventures Trading Limited, London (GB)
Filed on Sep. 4, 2020, as Appl. No. 17/012,439.
Prior Publication US 2022/0071272 A1, Mar. 10, 2022
Int. Cl. A24B 15/42 (2006.01); A24B 15/24 (2006.01); A24B 15/26 (2006.01)
CPC A24B 15/42 (2013.01) [A24B 15/26 (2013.01)] 27 Claims
OG exemplary drawing
 
1. A method of preparing a whitened tobacco material, comprising:
(i) extracting a tobacco material with a first extraction solution to provide a tobacco solids material and a tobacco extract;
(ii) cooking the tobacco solids material in an alkaline cooking liquid comprising sodium sulfide and having a pH of greater than 11 to form a tobacco pulp;
(iii) treating the tobacco pulp with an acid to lower the pH of the tobacco pulp and provide a neutralized tobacco pulp;
(iv) extracting the neutralized tobacco pulp with a second extraction solution comprising at least one chelating agent to provide an extracted tobacco pulp; and
(v) bleaching the extracted tobacco pulp with a bleaching solution to provide a whitened tobacco material.