Ukers's chemistry chapter shows that putting the pulp to use is nothing new. Trigg lists there “various schemes” proposed to use “the large quantity of pulp” coming from coffee preparation. Most rely on fertilizer, the fresh pulp containing 2.61% nitrogen, 0.81% P2O5, 2.38% potassium and 0.57% calcium.

A Mexican process (Sencial, El Hacendado Mexicano) consists of mixing the pulp with sawdust, urine and a little lime, then leaving it all covered in a pit for a year. The pulp also contains about 0.88% caffeine and 18 to 37% sugars; R. Pique, in the Bulletin de l'Association des chimistes de sucrerie et de distillerie, proposes extracting the caffeine with chloroform and the sugars with acidulated water, fermenting the solution into alcohol, burning the insoluble residue as fuel and spreading the ash as fertilizer.

Compost, caffeine extraction, bioethanol, combustion: four of the routes the ICO presents in 2024 are described, with their figures, a century earlier. What was missing was not the idea but the equipment, the outlet and the intermediary.

Ukers 1922, ch. XVII (Trigg), p. 155 sq., n. 105-107 (Gorter; Schulte; Loew, Ann. Rep. Porto Rico Agr. Expt. Sta. 1907, p. 41-55; Sencial; Pique, Bull. Assoc. Chim. sucr. dist., xxiv, p. 1210-1213)

Mulching with husks has remained the basic peasant practice. The Uganda canephora handbook (2019) ranks coffee husks among the organic mulching residues with bean vines, corn stalks and banana leaves, but it warns that husks from infected cherries can carry coffee wilt disease (wilting of the coffee plant, see the diseases) and advises against mulching coffee plantations with coffee husks as long as the disease has not been eradicated from the country. The simplest by-product to recycle on site is also a sanitary vector.

UCDA, Robusta Coffee Handbook (2019), § 3.2.2 Mulching and § 7.1 Coffee wilt disease