초록
<P><B>Abstract</B></P> <P>Food waste landfilling causes environmental degradation, and this work assesses a sustainable food valorization technique. In this study, food waste is converted into lactic acid in a batch assembly by dark fermentation without pH control and without the addition of external inoculum at 37 °C. The effect of total solid (TS), enzymatic and aeration pretreatment was investigated on liquid products concentration and product yield. The maximum possible TS content was 34% of enzymatic pretreated waste, and showed the highest lactic acid concentration of 52 g/L, with a lactic acid selectivity of 0.6 g<SUB>lactic</SUB>/g<SUB>totalacids</SUB>. The results indicated that aeration pretreatment does not significantly improve product concentration or yield. Non-pretreated waste in a 29% TS system showed a lactic acid concentration of 31 g/L. The results showed that enzymatic pretreated waste at TS of 34% results in the highest production of lactic acid.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Increase of total solids increased the total organic acids product concentration. </LI> <LI> Enzymatic pretreatment helps to increase to total solid content from 29% to 34% </LI> <LI> Enzymatic pretreatment increased by 55% the product yield to a 0.28 g<SUB>liqprod</SUB>/g<SUB>TS.</SUB> </LI> <LI> Enzymatic pretreated waste produced highest amount of 52 g/L lactic acid. </LI> <LI> Aeration pretreatment has not significantly improved lactic acid production. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>