Methods for using phytase in ethanol production

A method for improving efficiency of ethanol production by yeast, the method comprising:

• (a) adding a variant polypeptide comprising an amino acid sequence that is at least 85% identical to the amino acid sequence as set forth in amino acid residues 23-434 of SEQ ID NO:2 or that is at least 85% identical to the amino acid sequence as set forth in SEQ ID NO:3 to an ethanol processing fluid in an ethanol production facility, wherein the ethanol processing fluid comprises phytic acid, wherein the addition of the phytase variant polypeptide improves ethanol production efficiency comprising one or more of:
• increased yeast cell count, yeast budding or yeast viability;
• increased ethanol yield, decreased glycerol levels, or decreased total sugar levels;
• decreased fouling rate;
• increased phosphorous levels;
• and
• increased operation time of the ethanol production facility when compared to a production process wherein a wild-type phytase consisting of the amino acid sequence as set forth in Seq ID No:
• 2 amino acid residues 23-434 of Seq ID No:
• 2 is added to the ethanol processing liquid.