TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Components: The feedstock comprises one or more fermentable sugars chosen from corn grain, corn cobs, crop residues such as corn husks, corn stover, grasses, wheat, rye, wheat straw, barley, barley straw, hay, rice straw, switchgrass, waste paper, sugar cane bagasse, sorghum, sugar cane, soy, components obtained from milling of grains, cellulosic material, lignocellulosic material, trees, branches, roots, leaves, wood chips, sawdust, shrubs and bushes, vegetables, fruits, flowers, animal manure, and their mixtures. Preferred Method: The method further involves converting at least a portion of the oil obtained from the oil stream into carboxylic acid. The feedstock slurry is separated by decanter bowl centrifugation, tricanter centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, beltfilter, pressure filtration, screen filtration, screen separation, grating, porous grating, flotation, hydroclone, filter press, screw press, gravity settler, vortex separator or their combinations. The carboxylic acid comprises 12-22C fatty acids. The method further involves adding additional carboxylic acid to the fermentation vessel. The method involves converting the obtained oil to carboxylic acid after the step of adding the additional carboxylic acid. The carboxylic acid is chosen from corn oil fatty acid, soybean oil fatty acid and their mixtures. The oil comprises glycerides and one or more catalysts hydrolyze the glycerides into fatty acids. The catalyst is an enzyme, preferably esterase, lipase, phospholipase, or lysophospholipase capable of esterifying the carboxylic acid with the butanol to form butyl esters of the carboxylic acid. The method involves recovering butanol from the butyl esters by hydrolyzing the esters into carboxylic acid and butanol and transesterifying the butyl esters into butanol and other fatty acid alkyl esters or acylglycerides. The butyl esters are hydrolyzed in presence of hydrolysis catalyst. The hydrolysis catalyst comprises an acid catalyst, organic acid, water-soluble acid, water-insoluble acid or base and an enzyme capable of hydrolyzing the butyl esters to form a carboxylic acid and butanol. The other fatty acid alkyl esters are chosen from fatty acid methyl esters, fatty acid ethyl esters and fatty acid propyl esters. The solids are processed to form animal feed product. Preferred Composition: The composition further comprises oil, where the oil comprises glycerides. The oil, free fatty acids and fermentable carbon substrate are derived from biomass. The oil and fermentable carbon substrate are derived from the same biomass source or from different biomass sources. The free fatty acids are formed from hydrolysis of at least a portion of the glycerides in the oil using catalyst. The composition further comprises at least one of diglycerides and monoglycerides formed from the partial hydrolysis of a portion of the glycerides in the oil using catalyst, glycerol, saccharification enzyme capable of converting starch into fermentable sugar, where the alcohol is butanol. EXAMPLE - No suitable example given.