Source: UNIVERSITY OF ILLINOIS submitted to NRP
VALORIZATION OF PROTEINS IN WHEY WASTE THROUGH ELECTROCHEMICALLY-DRIVEN CONTINUOUS SEPARATIONS FOR SUSTAINABLE DAIRY MANUFACTURING
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1030644
Grant No.
2023-67017-39833
Cumulative Award Amt.
$504,000.00
Proposal No.
2022-09193
Multistate No.
(N/A)
Project Start Date
May 1, 2023
Project End Date
Apr 30, 2026
Grant Year
2023
Program Code
[A1364]- Novel Foods and Innovative Manufacturing Technologies
Recipient Organization
UNIVERSITY OF ILLINOIS
2001 S. Lincoln Ave.
URBANA,IL 61801
Performing Department
(N/A)
Non Technical Summary
Whey waste is a major challenge for waste treatment due to its large production globally. Whey contains key nutrient proteins which can be recovered and valorized as food products. However, recovering high-purity food-grade protein from whey can be very challenging, due to the complexity of the whey composition. Current protein purification technologies are highly costly step for whey valorization, due to the high consumption of chemicals, water, and the large number of separation processes required. The development of new purification technologies tailored at whey protein recovery can greatly benefit the environment, agriculture, and society by providing a sustainable source of food products, while at the same time treating a major waste ource. Electrochemically-mediated technologies have the potential to greatly improve sustainability of protein separations by removing the need for regeneration chemicals, extensive elution, or thermal input.Redox-electrodialysis can provide a modular platform for whey protein valorization, due to the use of low voltage - allowing for control of pH, low energy-consumption, and selective recovery. Here, we seek to develop a modular, molecularly-selective system for the recovery of whey proteins from acid, sweet, and salty whey, through desalination of the inorganic salts and the purification of valuable nutrient proteins. We design a new modular membrane-electrode arrangement for multicomponent recovery, and study the structure-function relationship of size and charge of proteins with selectivity. Finally, we seek to improve the robustness of the redox-flow moiety to eliminate crossover and enable long-term operation. The combination of these tasks will lead to a modular, energy and resource efficient method for producing valuable food products from whey streams. Our project involves a close partnership with food manufacturing end-users, including dairy manufacturers and food waste.
Animal Health Component
30%
Research Effort Categories
Basic
50%
Applied
30%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5013470202060%
1110210202020%
5013470200020%
Knowledge Area
111 - Conservation and Efficient Use of Water; 501 - New and Improved Food Processing Technologies;

Subject Of Investigation
0210 - Water resources; 3470 - Other dairy cattle products;

Field Of Science
2020 - Engineering; 2000 - Chemistry;
Goals / Objectives
The overarching goal of the project is to innovate agricultural food manufacturing in the U.S. by developing more efficient technologies for dairy manufacturing, through the recovery and valorization of proteins from whey waste. We propose to develop redox-polymer driven electrodialysis flow cellsto enable multi-component separation of whey proteins and salts for food manufacturing through the rational arrangement of selective membranes and redox-channels. The project pursues an integrated approach between process engineering, systems design, and redox materials synthesis, for the implementation of a novel separation technology in food manufacturing through whey protein recovery and purification. The following objectives will be followed in the current proposal:Objective 1.Investigate various whey waste compositions (e.g., acid, sweet, salty whey) to screen and source whey proteins that are selectively separable for valorization.Objective 2.Develop electrochemically-mediated flow system based on redox electrolyte for continuous and selective salt and protein separation of whey waste stream.Objective 3.Synthesize and engineer green redox polymers to facilitate usage of nanofiltration membranes and minimize crossover and interactions with proteins.Objective 4.Technoeconomic analysis of the redox-ED system and evaluation of the multi-channel system for relevant food manufacturing samples from the dairy industry.
Project Methods
Methodology for Objective 1: First, we seek to select, characterize, and create a library of whey waste compositions to benchmark both industrial whey samples from collaborators, and formulate a model to represent various types of acid, sweet, and salty whey wastes. We then aim to establish characterization methods to understand the composition and separation parameters of whey waste based on the charge, mass, and polarity of complex molecules present in whey. Next, we seek to: (i) Benchmark compositions from industrial whey samples from dairy manufacturers, and (ii) Gather data to formulate synthetic whey waste of target components. Accurate quantitation of the composition of whey before and after treatment will be key for the remainder of the project. Analytical accuracy >95% for both salt and protein concentration measurements are envisioned using chromatography and ion-conductivity measurements.Methodology Objective 2: We aim to fabricate, design and develop continuous and scalable electrochemically-driven redox flow system to separate salt and protein by providing multiple flow channels that are distinguished by membrane separators. We seek to draw structure-function correlations between operating conditions of flow, membrane properties, and protein parameters (isoelectric point, size, charge, and hydrophobicity), as well as identify potential ranges for protein stability. In addition, we will achieve fractionation of proteins using membranes with a wide range of molecular weight cut off and functionality. Target protein recovery from the total whey mixture will be aimed at 80%, with individual component protein purity >95% by the end of the project.Methods/Efforts from Objective 3:Research Task 3a: Design and synthesize water soluble redox-active polymers with tunable size, which can be effectively retained by low-cost nanofiltration membranes. Research Task 3b: Tuning of charge and electrochemical properties of redox polymers to minimize denaturation of valuable proteins and maximize long term operational stability. Expected Outcomes of Objective 3: Successful completion of Objective 3 will result in a versatile platform of watersoluble redox copolymers for usage in nanofiltration membrane based electrochemically-mediated flow systems, with a structure optimized for high separation performance, low membrane crossover and improved compatibility with a wide range of proteins. We will aim at non-detectable cross-over (100% retention) of the redox-species and >95% retention of charge for >10,000 hours of operational stability in redox-cycling.Methods/Efforts from Objective 4: Research Task 4a. Operate developed flow system using conditions suitable for industry, including real world whey protein waste sourced from industrial collaborators. Research Task 4b. Develop a process model for scaleup, and conduct preliminary technoeconomic analysis (TEA) for estimation of cost, recovery yields and operating costs for whey protein separation for end-user food manufacturing. Expected Outcomes of Objective 4: Successful completion of research Tasks 4a and 4b will provide economic feasibility and inform optimal electrochemical system arrangements of the system based on the whey waste sources. The combination of real whey waste valorization in Task 4a with techno-economic analysis in Task 4b will provide a comparative landscape to evaluate the industrial applicability of the electrochemically-mediated ED system.

Progress 05/01/24 to 04/30/25

Outputs
Target Audience:During this reporting period, our efforts primarily reached academic audiences, including scientists, engineers, and researchers in sustainable food waste valorization, electrochemical science and engineering, redox polymers and chemical engineering through presentations and publications. In addition, we engaged our industry collaboratorsin preliminary discussions about potential applications of the redox-ED system. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?1. To characterize the membranes, we received training in the X-ray laboratory on Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR). This is in addition to training already received in the first year on high-performance liquid chromatography (HPLC), ion chromatography (IC), and circular dichroism (CD). 2. In addition to the existing project team, we recruited and trained a new graduate researcher to work on organic acid recovery using the redox-ED system. The project remains engaged with now two graduate students, a postdoc, and an undergaduate. How have the results been disseminated to communities of interest?The project over the past year has yielded one published peer-reviewed paper, one submitted paper, and 5 conference presentations. The project was disseminated by the students in oral presentations at major conferences including the ACS, AIChE, and MRS conferences in 2024-2025 timeframe. What do you plan to do during the next reporting period to accomplish the goals?The next year of the project will focus on scaling up the redox-ED system to handle larger volumes of whey, moving us closer to industrially relevant applications. Specifically, we will investigate the effects of cell size, cell stacking, and electrode count on system productivity, energy efficiency, and membrane durability. These efforts will help provide insights into optimizing the redox-ED system for large-scale whey demineralization and implementing its real-world implementation. We also plan to extend the technologies for application in broader protein separation case scenarios.

Impacts
What was accomplished under these goals? Objective 1.Investigate various whey waste compositions (e.g., acid, sweet, salty whey) to screen and source whey proteins that are selectively separable for valorization. We analyzed skimmed whey sourced from our collaborators in Leprino, the dairy food and ingredient company. Our investigation comprised both laboratory analysis and nutritional analysis of demineralized whey. In the lab, protein content in the whey was quantified using high-performance liquid chromatography (HPLC) and salt levels were measured through ion chromatography (IC). In addition, protein structures were examined using circular dichroism to help us assess how our redox electrodialysis system impacted protein functionality. Since the key project centered on demineralizing whey proteins to enhance their application in dairy-based foods, we evaluated the nutritional contents of the demineralized whey produced using our redox electrodialysis system. We utilized the Nutrient Rich Foods (NRF) 9.3 index - a metric of the nutrient density in food based on regulatory frameworks and dietary guidance. This index considers nine recommended nutrients (protein, fiber, vitamins A, C, and E, calcium, iron, potassium, and magnesium) and three nutrients to limit (saturated fat, added sugar, and sodium). Our findings revealed that demineralized whey, particularly the 50% demineralized, retains a strong nutritional profile while offering a reduced mineral content. This makes it a valuable ingredient for formulating nutritionally balanced products. Objective 2.Develop electrochemically mediated flow system based on redox electrolyte for continuous and selective salt and protein separation of whey waste stream. Redox electrodialysis (redox-ED) is an emerging flow-based separation technology that utilizes redox reactions to drive ion removal from feed solutions, whey in our case. While promising, the commercialization of redox-ED has been hindered by its reliance on costly and fouling-prone ion exchange membranes (IEMs). To address these limitations, we explored the use of nanofiltration membranes (NF) as a cost-effective and energy-efficient alternative within the redox-ED system. Our approach involved integrating NF membranes into the redox-ED cell in place of conventional IEMs. We investigated the effects of membrane configuration - specifically, the number and placement of NFs - on key performance metrics, including demineralization efficiency, protein retention, and energy consumption. The most effective setup was identified as the NF-CEM-NF configuration, which combines nanofiltration membranes with a cation exchange membrane in the middle. This optimized configuration demonstrated high demineralization efficiency (up to 90%), excellent protein retention (over 95%), and reduced energy consumption compared to systems relying solely on IEMs. Furthermore, the system was validated using real skimmed whey from our collaborators in Leprino, achieving 50% demineralization while maintaining protein integrity and structure. Importantly, unlike anion exchange membranes (AEMs), the NF membranes showed no signs of fouling during operation. This suggests a potential for improved long-term membrane performance, reduced maintenance frequency, and lower overall system costs through extended membrane lifespan. Objective3.Synthesize and engineer green redox polymers to facilitate usage of nanofiltration membranes and minimize crossover and interactions with proteins. The water-soluble redox polymer synthesized in the first year was poly(ferrocenylpropylmethacrylamide-co-[2-(methacryloyloxy)ethyl]trimethylammonium chloride), P(FPMAm-co-METAC). The high molecular weight of the polymer enabled effective retention by the nanofiltration membranes. More recently, we optimized the copolymer composition to a 25:75 ratio, balancing sufficient ferrocene units to support the redox reaction while properly maintaining water solubility. Objective4.Technoeconomic analysis of the redox-ED system and evaluation of the multi-channel system for relevant food manufacturing samples from the dairy industry. A technoeconomic analysis was conducted for the redox-ED system utilizing the NF-CEM-NF membrane configuration. Replacing IEMs with NFs led to a 58% reduction in total membrane costs from $1,091 for an all-IEM setup to $459 for the NF-CEM-NF configuration. This cost reduction was as result of the significantly lower price of NFs, which are 85-90% cheaper than IEMs. As a result, the capital cost of the system decreased by 54%, and operating costs were reduced by 48%. Overall, the technoeconomic assessment confirmed that the NF-CEM-NF redox-ED system presents a cost-effective, energy-efficient, and high-performing solution for whey demineralization.

Publications

  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: N. Kim, A. Aguda, C. Kim, X. Su, ACS Energy Lett. 2024, 9, 8, 38873912
  • Type: Other Journal Articles Status: Under Review Year Published: 2025 Citation: A. Aguda, N. Kim, E.F. Harbut, J. Elbert, J. Li, R. Merrill, C. Kim, X. Su. Architecture design of Nanofiltration-based Redox Electrodialysis for Whey Protein Valorization
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: N. Kim, J. Lee, J. Jeon, J. Elbert, X. Su. Electrochemical Recovery of Biomolecules in Redox-Mediated Electrodialysis Platform. 245th Electrochemical Society Meeting, San Francisco, California, May 26-30, 2024.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: N. Kim, J. Elbert, X. Su. Electrochemical Separations Through Redox Polymer Design. 98th ACS Colloid and Surface Science Symposium, Seattle, Washington, June 23-26, 2024.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: N. Kim, J. Elbert, X. Su. Advances in Redox-Electrodialysis for Desalination and Water Remediation. American Institute of Chemical Engineers, San Diego, October 27-30, 2024.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: W. Oh, N. Kim, H. Kim, R. Mackie, X. Su, Nanostructured Thin-Film Composite Membranes for Redox Flow Electrochemical Separations. Materials Research Society Fall Meeting, Boston, Massachusetts, December. 1-6, 2024.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: J. Elbert, N. Kim, X. Su. Redox-polymer electrodialysis: Energy efficient desalination and PFAS removal enabled by copolymer design. American Chemical Society (ACS) Spring 2025 Meeting & Expo, San Diego, California, March 23  27, 2025.


Progress 05/01/23 to 04/30/24

Outputs
Target Audience:The target audience for the work is the scientific community on bioseparations, food manufacturing, and polymer design. We are also targeting relevant industry in dairy manufacturing, as well as the general public for the extended outreach of the work. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?1. For whey and cell culture characterization, we were trained on high-performance liquid chromatography (HPLC), ionic chromatography (IC) and inductively coupled plasma - opticalemission spectrometry (ICP-OES). We also collaborated with the X-ray Laboratory on campus to conduct circular dichroism on whey proteins and proteins in cell culture media to investigate their stability. 2. We recruited and trained one undergraduate researcher on colorimetry, chronoamperometry and chronopotentiometry experiments. How have the results been disseminated to communities of interest?As of April 2024, we have two publications (one has been submitted and one is under preparation) and have submitted the abstract for one conference presentation Presentations A. Aguda, N. Kim, J. Elbert, X. Su. Valorization of Whey Proteins via Redox-Mediated Electrodialysis. Division of Agricultural and Food Chemistry at ACS Fall 2024, Denver, CO, United States (Submitted for Aug 2024) N. Kim, A. Aguda, J. Lee, J. Jeon, J. Elbert, X. Su. Advancements in Redox-Mediated Electrodialysis for Valorization of Biomolecules. F01 - Advances in Industrial Electrochemistry and Electrochemical Engineering at ECS PRiME 2024, Honolulu, HI, United States (Submitted for Oct 2024) Publications Lee, J., Huang, K., Knust, K., Kim, N., Oh, W., Fernandes, S. M., Hatz, S., Fennelly, C., Kong, H., Su, X., Recycling spent cell culture media through redox-mediated electrodialysis. (Submitted) Kim, N., Aguda, A., Kim, C., Su, X. Redox-Electrodialysis for Desalination, Environmental Remediation, and Resource Recovery. (Submitted) Aguda, A., Kim, N., Elbert, J., Su, X., Valorization of Whey Proteins using Nanofiltration Membranes. (In preparation) What do you plan to do during the next reporting period to accomplish the goals?1. Understand the impact of different operating conditions on the redox-ED and perate our flow system at industrially suitable conditions with whey sourced from Leprino 2. Conduct a preliminary technoeconomic analysis on our system and compare with existing technologies for whey purification 2. Expand on this research by applying our redox-ED system to valorize or separate other relevant agricultural components

Impacts
What was accomplished under these goals? Objective 1.Investigate various whey waste compositions (e.g., acid, sweet, salty whey) to screen and source whey proteins that are selectively separable for valorization. High performance liquid chromatography was used to characterize the proteins and organic acids present in sweet whey sourced from industrial cheese-manufacturing plant, Leprino. Circular dichroism was also used to assess and understand the stability and conformational changes of the proteins. Objective 2.Develop electrochemically mediated flow system based on redox electrolyte for continuous and selective salt and protein separation of whey waste stream. We developed a redox electrodialysis flow system with three independent channels (feed, accumulating and redox channels) separated by membranes. The feed channel contains the waste stream, which is demineralized under an applied voltage, thereby purifying, and concentrating the proteins. The ions migrate to and are concentrated in the accumulating channel while the redox channel contains the redox electrolyte which is continuously circulated to drive the system. The flow system was successfully utilized to demineralize whey waste and selectively segregate metabolic byproducts from cell culture media for protein purification. Redox-ED achieved >90% demineralization of synthetic whey solutions and cell culture media was also demineralized up to 80% while preserving the proteins and their structure. Objective3.Synthesize and engineer green redox polymers to facilitate usage of nanofiltration membranes and minimize crossover and interactions with proteins. We synthesized a water-soluble redox copolymer containing ferrocene as the redox couple - poly(ferrocenylpropylmethacrylamide-co-[2-(methacryloyloxy)ethyl]trimethylammonium chloride), P(FPMAm-co-METAC). The macromolecular structure of the copolymer enables the usage of nanofiltration membranes in our redox-ED system. We also optimized the polymer design based on desired electrochemical and material properties. Objective4.Technoeconomic analysis of the redox-ED system and evaluation of the multi-channel system for relevant food manufacturing samples from the dairy industry. The feasibility of redox-ED for the refinement of proteins in cell culture media was investigated. Our redox-ED system decreased the material usage efficiency by up to 34% indicating an environmentally and economically beneficial system.

Publications

  • Type: Conference Papers and Presentations Status: Submitted Year Published: 2024 Citation: A. Aguda, N. Kim, J. Elbert, X. Su. Valorization of Whey Proteins via Redox-Mediated Electrodialysis. Division of Agricultural and Food Chemistry at ACS Fall 2024, Denver, CO, United States
  • Type: Conference Papers and Presentations Status: Submitted Year Published: 2024 Citation: N. Kim, A. Aguda, J. Lee, J. Jeon, J. Elbert, X. Su. Advancements in Redox-Mediated Electrodialysis for Valorization of Biomolecules. F01 - Advances in Industrial Electrochemistry and Electrochemical Engineering at ECS PRiME 2024, Honolulu, HI, United States (Submitted for Oct 2024)
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2024 Citation: Kim, N., Aguda, A., Kim, C., Su, X. Redox-Electrodialysis for Desalination, Environmental Remediation, and Resource Recovery. (Submitted)
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Lee, J., Huang, K., Knust, K., Kim, N., Oh, W., Fernandes, S. M., Hatz, S., Fennelly, C., Kong, H., Su, X. Recycling spent cell culture media through redox-mediated electrodialysis. (In Preparation)
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Aguda, A., Kim, N., Elbert, J., Su, X. Valorization of Whey Proteins using Nanofiltration Membranes. (In preparation)