Global grape production could generate up to 13. Mt/yr of wasted biomass. The compositions of Cabernet Sauvignon (red marc) and Sauvignon Blanc (white marc) were analyzed with a view to using marc as raw material for biofuel production. On a dry weight basis, 31-54% w/w of the grape marc consisted of carbohydrate, of which 47-80% was soluble in aqueous media. Ethanol insoluble residues consisted mainly of polyphenols, pectic polysaccharides, heteroxylans and cellulose. Acid and thermal pre-treatments were investigated for their effects on subsequent cellulose saccharification. A 0.5. M sulfuric acid pre-treatment yielded a 10% increase in the amount of liberated glucose after enzymatic saccharification. The theoretical amount of bioethanol that could be produced by fermentation of grape marc was up to 400. L/t. However, bioethanol from only soluble carbohydrates could yield 270. L/t, leaving a polyphenol enriched fraction that may be used in animal feed or as fertilizer.
|Number of pages||8|
|State||Published - Oct 1 2015|
Bibliographical noteFunding Information:
This work was financially supported by the Australian Research Council , NSF EPSCoR Grant (S.D.) and USDA Hatch funds (J.S.). Thanks to Waite Analytical Services for assistance with elemental and nitrogen measurements, Professor Peter Hoffmann at the Adelaide Proteomics Centre for assistance with mass spectrometry, and Professor Vincent Bulone (University of Adelaide) for critical reading of the manuscript.
- Grape marc
ASJC Scopus subject areas
- Environmental Engineering
- Renewable Energy, Sustainability and the Environment
- Waste Management and Disposal