Protein feed compositions and methods of making same
View Patent ↗Protein feed compositions and methods of making the protein feed compositions are disclosed herein. The protein feed compositions may comprise zein and are derived from a starch-based feedstock-to-ethanol fermentation conversion process such as a corn-to-ethanol conversion process. Methods of making the compositions include performing a starch-based feedstock-to-ethanol fermentation process in a manner that reduces the total heat exposure of the components of the protein composition as compared to a similar process which uses a cooking process to saccharify starch and/or a distillation process to separate the fermentation beer into ethanol and whole stillage. The process may include centrifugation of the fermentation beer resulting in a bulk solids mixture, extraction of a protein composition from the resulting bulk solids mixture, and desolventizing the extracted protein composition.
1. A process, comprising:
a. separating a fermentation beer composition comprising a solids fraction and a liquids fraction into a first mixture comprising bulk solids and a minority portion of the liquids and a second mixture comprising fine solids and a majority portion of the liquids fraction;
b. using a solvent to extract a protein from the first mixture to form an extracted composition;
c. separating the extracted composition into an extracted solids fraction and an extracted liquids fraction, wherein the extracted liquids fraction comprises the protein; and,
d. at least partially de-solventizing the extracted liquids fraction to form a protein feed composition comprising the protein, wherein the process is performed in a manner that reduces the total heat exposure of the protein as compared to a process using distillation to initially separate the fermentation beer composition into ethanol and whole stillage and that the protein is not exposed to temperatures greater than 180° F.
2. A process according to claim 1 , wherein the protein is at least a zein.
3. A process according to claim 2 , further comprising saccharifying starch derived from a starch-based feedstock into sugar and fermenting the sugar into the beer composition.
4. A process according to claim 3 , wherein the process is performed in a manner that reduces the total heat exposure of the zein as compared to a process wherein saccharifying is done using a cooking process and a distillation is used to initially separate the beer composition into ethanol and whole stillage.
5. A process according to claim 4 , wherein separating the beer composition comprises centrifuging.
6. A process according to claim 4 , wherein separating the extracted composition comprises centrifuging.
7. A process according to claim 4 , further comprising adding liquid to the protein feed composition.
8. A process according to claim 4 , wherein the fine solids have an average particle size of about 30 μm or less, and the bulk solids have an average particle size of greater than about 30 μm.
9. A process according to claim 4 , wherein the fine solids have an average particle size of about 10 μm or less, and the bulk solids have an average particle size of greater than about 10 μm.
10. A process according to claim 4 , wherein the feed composition comprises, on a dry weight basis:
a. about 75% weight or greater crude protein;
b. about 10% weight or less crude fat;
c. about 20% weight or less neutral detergent fiber;
d. about 1% weight or less starch; and,
e. about 1% weight or less sugars.
11. A process according to claim 10 , wherein the amount of crude protein is about 95% weight or greater.
12. A process according to claim 10 , wherein the amount of crude protein ranges from about 78% to about 91%; the amount of crude fat ranges from about 1% weight to about 12%; and the feed composition further comprises 3% weight or less ash.
13. A process according to claim 4 , wherein saccharifying and fermenting are conducted at temperatures of about 100° F. or less.