4. Conclusions
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.