Q: Is there a white paper that outlines the data shown regarding “cost savings of 50%” and “using 40% less water?”
A: Yes, there is a case study on our website showing this data from a US-based whey processor using Evolution RO to concentrate effluent streams.
Q: Has ZwitterCo experienced an application where Evolution membranes were irreversibly fouled by organics (not considering blocking of feed channels), meaning an application where Evolution membranes were not able to be cleaned sufficiently? If so, what type of foulants caused this?
A: We have not experienced an application where Evolution membranes were irreversibly fouled by organics.
Q: Have Evolution reverse osmosis (RO) membranes been used for water recovery and the concentration of sugars and solubles side streams in plant protein manufacturing? If so, how do they handle fouling due to leftover insoluble proteins left in the product stream?
A: In terms of concentration sugars and other solubles, we do have an installation at a corn refiner using a superfiltration (SF)-RO treatment train. The feed has high solids and high viscosity, and they are doing product concentration. The treatment train utilizing our membranes has performed quite well.
In terms of water recovery in general, this is a huge potential application for ZwitterCo, both in plant protein and many other applications. Our membranes can recover water that is currently being sent to wastewater, including diafiltration water, rinse water, or process water. By utilizing our membranes in these applications, plants can reduce their freshwater demand and decrease the amount of wastewater being treated. With the coming food-grade certification, we plan to pursue water reuse for process and would gladly discuss trials with any plant that is interested.
Q: What is the upper limit of dry matter in concentrated skim milk that Evolution RO can handle (e.g. 30%, 35%, 40%, etc.)?
A: Thanks to the anti-fouling nature of the membrane, we believe we can achieve higher solids with Evolution RO versus conventional RO. While we do not have specific data on this application yet, we would happily run a trial with you at your plant to demonstrate this.
Q: If Evolution RO were to be used to concentrate sweet whey or milk, what would be the approximate BOD in the RO permeate?
A: The ZwitterShield™ technology in Evolution RO membranes improves fouling resistance and cleanability; however, it does not alter the rejection properties of the polyamide barrier layer in the membrane. Thus, we expect the BOD in the RO permeate to be roughly the same as what you are seeing with your conventional RO membranes.
Q: Regarding the graph on Slide 14 (showing field operation in a WPI process): can you explain why the flow of the conventional polyethersulfone (PES) ultrafiltration (UF) membrane is not continuous?
A: The graph contained data provided by our customer. On some days, data was only provided for the ZwitterCo Evolution SF membranes.
Q: What is your confidence in using Evolution membranes for nanofiltration (NF) applications for the desalination of salt whey?
A: Evolution SF is not designed to reject salt or lactose, so while it will retain protein, both lactose and salt will pass into the permeate. Because this will likely make disposal of the permeate an issue, desalination of salt whey is not seen as an ideal application for Evolution SF.
Q: You mention FDA-compliance for Evolution membranes, but will you also get USDA certification as well?
A: Evolution SF elements are already FDA-compliant for whey and milk processing, and FDA-compliant Evolution PCM and Evolution RO elements will be available by the end of 2025. We are pursuing additional certifications, including USDA, 3A Sanitary Standard 45-03, Halal, and Kosher for Evolution membranes. We have also begun working on European Regulation (EC) 1935/2004 for 2026.
Q: What is the status of EU food grade compliance for Evolution membranes? Is there any risk of zwitterions migrating or leaching into product?
A: ZwitterCo has begun pursuing European Regulation (EC) 1935/2004, with a target completion data in 2026. See the question above for further information on regulatory certifications.
A significant amount of analytical work has been performed while pursuing FDA compliance. These data confirmed that the potential constituents of the zwitterionic copolymer are present at such low levels, if at all, as to be safe to a reasonable certainty.
Evolution SF membrane elements, including their individual subcomponents, have been determined to comply fully with the Federal Food, Drug, and Cosmetic Act and applicable food additive regulations, including but not limited to 21 C.F.R. 174.5 (“General provisions applicable to indirect food additives”), when used consistent with guidelines.