Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Wet Fractionation for Improved Utilization of Alfalfa Leaves

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan

Citation:  Biological Engineering Transactions. 6(1): 29-42. (doi: 10.13031/2013.42631) @2013
Authors:   M. F. Digman, T. M. Runge, K. J. Shinners, R. D. Hatfield
Keywords:   Alfalfa, Fermentation, Fractionation, Lucerne, Protein, Silage, Wet fractionation

Utilization of alfalfa could be greatly improved if the protein-rich leaves were efficiently separated and preserved from the fibrous stems. This work envisions a new harvest scheme combining three processes: mechanical leaf separation, pressing, and anaerobic storage. To quantify the effectiveness of leaf dewatering, experiments were conducted in which leaves were pressed in a replicated factorial design, including maceration and four levels of backpressure. The amount of press filtrate extracted varied proportionally with press backpressure from 211 to 612 L Mg-1 fresh leaves and was composed of about 90% water. The resulting partially dewatered leaves were successfully ensiled and were found to be chemically similar to high-quality, whole-plant alfalfa silages. Additionally, we demonstrated that nutritionally valuable components in the press filtrate could be conserved by anaerobic storage. Based on our work, protein and lactic acid could be obtained from the ensiled press filtrate in quantities as high as 300 and 143 kg ha-1, assuming an average annual leaf yield of 10 Mg ha-1 and optimal process conditions. However, more work is necessary to determine these values.

(Download PDF)    (Export to EndNotes)