|Grohmann, Karel - RETIRED, USDA|
Submitted to: American Society of Agricultural Engineers
Publication Type: Abstract Only
Publication Acceptance Date: November 26, 2004
Publication Date: N/A
Technical Abstract: In the United States, over 1 million short tons of grapefruit were processed to produce juice during the 2003/04 growing season, most of which were processed in the state of Florida. Grapefruit juice processing results in approximately 50,000 short tons of peel waste, which is generally ground and dried to produce a low value cattle feed. Previous studies have utilized enzymes to hydrolyze pectin and cellulose in orange peel to produce sugars that can be fermented to produce ethanol, a biofuel whose use has substantially increased in recent years. This study explores using these enzymes to hydrolyze grapefruit peel. Pectinase, cellulase and beta-glucosidase enzymes were added to slurries of grapefruit peel and water and incubated for 24 h at 45 °C at an initial pH of 4.8. Total dissolved solids and sugar yields were determined for several enzyme loadings. Dissolved solids and sugar yields were similar to previous studies using orange peel, indicating grapefruit peel waste has potential has a feedstock for ethanol production.