Food and Beverages

Sugarcane bagasse, the fibrous residue from raw sugar production mostly consists of cellulose, hemicellulose and lignin. It is a potential source of carbohydrates if valorized in the food industry rather than burning for energy production. For pre-treatments, HTL at subcritical conditions (<374°C and <22 MPa) is favored because chemical and biological treatments produce undesirable by-products, are expensive and time-consuming. As natural emulsifi ers, the oligosaccharides liquefi ed by HTL treatment can be suitable candidates to replace synthetic surfactants, provided that they have amphiphilic ability to stabilize emulsions. Th e objective was to formulate O/W emulsions stabilized by liquefi ed oligosaccharides from HTL. In the HTL reactor, 3% (w/w) grinded bagasse (50 μm) was treated at 220°C, 30 min and 1 MPa. Th e liquefi ed portion was vacuum fi ltrated and freeze-dried for 48 h, before redissolving it in 5 mM Phosphate buff er solution (0.5-4 wt%) as continuous phase. Polytron (10,000 rpm, 5 min) and high-pressure homogenization (100 MPa, 4 passes) achieved O/W emulsions with soybean oil before storage at 25°C. By increasing emulsifi er concentration the interfacial tension decreased from 26 mN/m to 18 mN/m. Th erefore, the HTL liquefi ed oligosaccharides can reduce the interfacial tension between oil and water, so that reducing their tendency to separate. Droplet sizes showed that O/W emulsions with 3% emulsifi er had better stability with d3,2 diameter of 272 nm aft er 6 days. Th us O/W emulsion with HTL treated bagasse was successfully prepared and showed stability, proving it has good emulsifying capability.