This study established that the three studied yeasts were able
to grow on date by-products (an agri-food residues) leading to
ethanol production in batch fermentation. However, the
choice of the strain affected the bioproduction of ethanol.
Production of high levels of ethanol could be achieved by
using osmotolerant yeasts, such as Z. rouxii from concentrated
date syrup. However, it was preferable to use S. cerevisiae if the
culture medium is less concentrated in sugar.
Results of alcohol fermentation showed that date juice can
be a good feedstock for ethanol production, and it did not
negatively affect human food. However, some questions
remain to confirm the relevance of the proposed valorization
and before any transposition on an industrial scale. Indeed,
30,000 tons per year of “low quality” dates is it sufficient for an
industrial production of biofuel? Is it more interesting to
produce high added value products like glycerol? An economic
study is therefore needed before any industrial scale-up.