Methods of treating biomass to produce oligosaccharides and related compositions

A method for producing an ingredient for human consumption, the method comprising:

• (a) subjecting a biomass to a first pretreatment to reduce an average size of the biomass to produce a pretreated biomass;
• (b) subjecting the pretreated biomass to a second pretreatment comprising:
• (i) incubating the pretreated biomass in an aqueous solution to solubilize monosaccharides and/or disaccharides from the pretreated biomass;
• and
• (ii) removing a portion of the aqueous solution comprising solubilized monosaccharides and/or disaccharides to produce a second pretreated biomass;
• (c) subjecting the second pretreated biomass to a third pretreatment to increase a digestibility of the biomass to produce a third pretreated biomass, wherein the third pretreatment is performed after the second pretreatment;
• (d) contacting, in a solution or a suspension, one or more polysaccharide-cleaving enzymes and the third pretreated biomass to form one or more oligosaccharides;
• and
• (e) enriching the solution or suspension to increase a concentration of the one or more oligosaccharides to form the ingredient.