Methods and systems for producing ethanol using raw starch and fractionation

A fermentation method comprising:

• dry fractionating plant material comprising endosperm into components including fiber, germ and endosperm;
• separating the germ and fiber components of the fractionated plant material to form a remaining portion which includes the endosperm;
• reducing the size of particles in the remaining portion to form a reduced portion, wherein more than 50% of the particles fit through a sieve with a 0.5 min mesh;
• mixing the reduced portion with liquid comprising stillage;
• and
• fermenting the reduced portion in a reaction mixture under acidic conditions to form an aqueous component comprising ethanol and a solid material, wherein the reaction mixture comprises acid stable fungal alpha amylase and yeast.

A method of producing distiller's dried grains (DDG) and/or distiller's dried grains plus solubles (DDGS), the method comprising:

• dry fractionating plant material comprising endosperm into components including fiber, germ and endosperm;
• separating the germ and fiber components of the fractionated plant material to form a remaining portion which includes the endosperm;
• reducing the size of particles in the remaining portion to form a reduced portion, wherein more than 50% of the particles fit through a sieve with a 0.5 mm mesh;
• mixing the reduced portion with liquid comprising stillage;
• fermenting the reduced portion in a reaction mixture under acidic conditions to form an aqueous component comprising ethanol and a solid material, wherein the reaction mixture comprises acid stable fungal alpha amylase and yeast;
• and
• removing the aqueous component comprising ethanol and drying the solid material to produce distiller's dried grains and/or distiller's dried grains plus solubles.

A method of fermenting corn into a fermentation product comprising the steps of:

• dry fractionating the corn into a fractionated corn comprising a fiber component, a germ component and an endosperm component;
• inducing cavitation or disruption in the fractionated corn;
• separating at least a portion of the germ component and at least a portion of the fiber component of the fractionated corn so that the fractionated corn substantially comprises the endosperm component;
• mixing the fractionated corn with liquid comprising stillage;
• and
• simultaneously saccharifying and fermenting the fractionated corn substantially comprising the endosperm component in an aqueous composition under conditions to form the fermentation product.