Water consumption and wastewaters in fresh-cut vegetable production

Abstract

Controlled water use is an important component of sustainable fresh-cut vegetable production because of limited water resources, and also for controlling the quality of wastewater re-used in vegetable processing or for irrigating on fields. In our study the water consumption in vegetable processing plants varied from 1.5 to 5.0 m3 t-1 of finished product. In one plant, monitored over three years, almost 90% of water was used for washing and rinsing of vegetables, but more than 90% of the organic load of the wastewater was generated from the processing stage. The results including organic load and the microbial quality of the wastewaters showed that the wastewater should be treated before re-use. Separate treating of wastewaters from processing stage is recommended. Pre-treatment of wastewater using precipitation chemicals and sedimentation in basins decreased the organic load and total solids in the water, allowing further treatment of the waters.