Methods and systems for pre-fermentation treatment of organic waste

A method for pretreating organic waste prior to large-scale production of lactic acid or a salt thereof from the organic waste, the method comprising:

• (a) providing a non-sterile slurry of organic waste comprising non-reducing polysaccharides and reducing sugars;
• (b) maintaining the non-sterile slurry of organic waste of step (a) at a temperature in the range of 55° C. to 65° C. and at a pH in the range of 3.5 to 5.5 for a first time duration of at least 1 hour, to thereby suppress endogenous microbial activity in the organic waste;
• (c) raising the temperature of the non-sterile slurry of organic waste of step (b) to a temperature above the temperature of step (b) and between 65° C. to 85°° C. for a second time duration of at least 0.5 hour;
• (d) optionally adjusting the temperature to a temperature between 45° C. to 65° C.;
• and
• (e) adding one or more saccharifying enzymes to the non-sterile slurry of organic waste of step (c) or step (d) for hydrolyzing polysaccharides in the organic waste to release reducing sugars, to obtain saccharified organic waste.