| Abstract
| - Effects of a 20-h fermentation on cell wall polysaccharides from the mucilage of pulped coffee beanswere examined and compared to those of unfermented beans, on alcohol insoluble residues (AIRs),their hot-water-soluble crude pectic substances (PECTs), and their hot-water-insoluble residues(RESs). Yields and compositions were very similar: AIRs, which consisted of ∼30% highly methylatedpectic substances, ∼9% cellulose, and ∼15% neutral noncellulosic polysaccharides, exhibited noapparent degradation. However, PECTs from fermented beans were shown to have undergone aslight reduction of their intrinsic viscosity and weight-average molecular weight by capillaryviscosimetry and high-performance size-exclusion chromatography. After fermentation, hot-water-insoluble pectic substances of RES exhibited partial de-esterification. Removal of coffee bean mucilageby natural fermentation seems to result from a restricted pectolysis, the mechanism of which remainsto be elucidated. Keywords: Coffee; Coffea arabica L. var. typica Cramer; mucilage; fermentation; cell wallpolysaccharides
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