Filtration of subcritical water hydrolysates from red macroalgae byproducts with ultraporous ceramic membranes for oligosaccharide and peptide fractionation

An ultrafiltration-based process for oligosaccharide and peptide fractionation from a macroalgae subcritical water hydrolysate was studied. A wide range of separation results obtained depending on the membrane pore. 100 kDa cut-off size enough clarification with total retention colloidal materials. Oligosaccharides present in showed highest all membranes, glucans mostly, followed by galactans, finally arabinans. Peptides after treatment were some lowest rejected compounds, even using 5 membrane. The increase temperature 20 to 50 °C feed flow rate 6.6 11.2 L/h enhanced permeate flux membrane, without perturbing retention. Hermia's models identified cake layer resistance as major fouling filtrations at °C, but standard pore blockage principal mechanism °C. sequential filtration stages TMP = 1.1 bar examined. fractionated retentates 100, 1 membranes. final collected freeze-dried obtain peptide-rich solid (71 wt%) that could be used different applications.