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This work combines physical and biochemical analyses to scrutinize liquefaction and saccharification of complex lignocellulose materials. A multilevel analysis (macroscopic: rheology, microscopic: particle size and morphology and molecular: sugar product) was conducted at the lab-scale with three matrices: microcrystalline cellulose (MCC), Whatman paper (WP) and extruded paper-pulp (PP). A methodology to determine on-line viscosity is proposed and validated using the concept of Metzner and Otto (1957) and Rieger and Novak's (1973). The substrate suspensions exhibited a shear-thinning behaviour with respect to the power law. A structured rheological model was established to account for the suspension viscosity as a function of shear rate and substrate concentration. The critical volume fractions indicate the transition between diluted, semi-diluted and concentrated regimes. The enzymatic hydrolysis was performed with various solid contents: MCC 273.6 gdm/L, WP 56.0 gdm/L, PP 35.1 gdm/L. During hydrolysis, the suspension viscosity decreased rapidly. The fibre diameter decreased two fold within 2 h of starting hydrolysis whereas limited bioconversion was obtained (10-15%).

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Rice papers made of non-glutinous rice are a common food item in Vietnam and Thailand. Called as Banh Da Nem in Vietnam, rice papers are used very often in the making of a traditional dish called Nem, i.e., Vietnamese spring rolls. The amino acid content in the rice papers extracted with water was found to be 2 to 3 fold higher than that in cooked rice, showing that the protein was resolved by microbial enzymes during the rice paper processing. Among organic acids, Iactic acid is most common in rice papers, indicating that lactic bacteria is involved in the nranufacturing. Many Gram-positive bacteria: Streptococcus constellatus, Streptococcus acldominimus, Staphylococcus capitis, Lactobacillus curvatus, Lactobacillus salivarius, and Gram-negative bacteria: Enterobacter cloacae, Klebsiella sp., Pseudomonas sp., along with wild type yeast were isolated from the milled-rice.