Protein recovery from potato processing water using ultrafiltration membrane
Hundreds of megaliters per annum of wastewater can be generated as a by-product of vegetable processing in a single plant and pose a costly stream for treatment. However, these waste streams contain commercially valuable proteins and provide an important opportunity for waste utilization. For example native potato proteins have high functionality and nutritional value and are considered as one of the best plant proteins. They can be utilized in food applications if recovered in native form with high quality and be isolated by the methods that do not result in denaturation. Patatin, the major protein of potato of high functionality, forms around 40% of the whole protein for different cultivars of potato. Essential amino acid index of patatin is 89% which is relatively high comparing to EAAI of many animal and plant proteins. However, traditional concentration, heat-coagulation and precipitation methods often produce poor protein functionality and usability. The objective of this research is to investigate the recovery of proteins from potato processing water using a combination of membrane processes to preserve protein value. Membrane technology has been used successfully to recover proteins from dilute waste streams such as cheese whey, utilizing a combination of concentration and diafiltration steps. In this study, the focus will be on potato protein recovery and processing while mitigating the fouling. Membrane fouling by protein has always been a challenge for membrane use in the food industry due to environmental and economic factors. A reduction in separation efficiency and consecutive replacement of the fouled membrane can be minimised by regular chemical cleaning. For this purpose, conventional membrane configurations to handle high solids concentrations will be explored in addition to different pre-treatments. Characterization of protein fractions/functionality, membrane fouling, protein denaturation and recovery will be incorporated.
Collaborators: Simplot Australia
Funding body: ARC training centre for Advanced Technologies in Food Manufacture