The combined Ultraflo and Viscozyme treatment resulted in thegreatest reduction in insoluble cell wall fibre materials in the cake(Table 2). This indicates that complementary hydrolytic activitieswere obtained by Viscozyme and Ultraflo coupled with LAB fermentation. Also, all the enzymatic treatments of the cassava cakeresulted in a great reduction in the particle size of the fibre materials compared to the untreated control. Light microscopy of the cakeinsoluble solids after removal of starch also revealed considerabledifferences in the cell wall material appearance (Fig. 1b). With thecombined enzyme treatment, the thin parenchyma cell walls haddisappeared, and the remaining materials were thick, dark stainedcell walls, indicating lignified material. The concentration of thelignified cell walls shows that these were not degraded by theenzyme preparations. This is because lignified materials containfew hydrolysable bonds and are poorly susceptible to hydrolyticenzymes (Marsden and Gray, 1986). The thin parenchyma cell wallsare not lignified (McCluskey et al., 1984), which explains theircomplete degradation by the enzymes. In contrast, the untreated control still had clusters of intact thin parenchyma cell wall mate-rials present (Fig. 1b).