UWRF Assistant Professor Grace Lewis is researching potential new uses for milk ingredients and byproducts in the Dairy Plant.

UWRF Dairy Innovation Hub researches potential new uses for milk ingredients and byproducts

June 15, 2022 – University of Wisconsin-River Falls Assistant Professor Grace Lewis is looking to find value-added products for milk proteins.

Lewis, who is part of the College of Agriculture, Food and Environmental Sciences, was hired and started in August through funding from the Dairy Innovation Hub to specialize in dairy processing. Her position is 60% research and 40% teaching.

The Dairy Innovation Hub, which launched in 2019, harnesses research and development at UW–Madison, UW–Platteville and UW–River Falls to keep Wisconsin’s dairy community at the global forefront of producing nutritious dairy products in economically, environmentally and socially sustainable ways. It is supported by a $7.8 million annual investment by the State of Wisconsin. Lewis has recently received support from the Dairy Innovation Hub on two research projects.

The Dairy Innovation Hub awarded Lewis $50,000 funding in April for a two-year study that will investigate high-pressure homogenization and other processing aids to alter the most abundant protein in milk, casein. The goal is to optimize the process of using casein proteins as an encapsulation compound for use in the food or pharmaceutical industries. Casein is highly digestible and could help protect food compounds, medicines, or vitamins from heat and light stressors while also increasing the bioavailability of the encapsulated compound.

Finding uses for whey

Lewis is also working with Youngmi Kim, associate professor in the Agricultural Engineering Technology Department, on another two-year project funded through the hub for $100,000 that will study the use of whey proteins from milk in combination with other food waste products to create biodegradable food packaging or food container materials.

Kim pointed out that whey is generated in large volumes as a by-product of cheese manufacturing but because of its high organic load can be difficult to dispose of. It contains 55% of the total nutrients of milk and has been used as a protein source in the food and beverage industry.

“Diversifying whey protein applications and expanding markets for whey is important for a sustainable dairy economy,” Kim said. “Our research focuses on developing a food packaging film/coating material based on whey protein. We particularly are interested in improving the properties of whey-based film/coating by incorporating lignin, a renewable polymer derived from plants. We expect that lignin will improve the mechanical strength and water barrier properties of whey-based film/coating. The whey-based film/coating can be used as a packaging material for dairy products -- liquid milk, soft cheese, yogurt, etc. -- to improve the overall sustainability of dairy products. The long-term potential outcomes of this project include diversifying whey protein applications and expanding markets for whey, reducing whey disposal and its associated pollution problems and fostering the growth and sustainability of whey market and economy.”

The DIH funding will purchase a texture analyzer that can be used in several food science and food process engineering courses at UWRF. The funding will benefit students not directly involved in the research, Kim said.

“I am excited to be working with the Dairy Innovation Hub collaboratively,” Lewis said. “It is all about helping the dairy industry. We are trying to find ways to move the dairy industry into the future and to find new uses for dairy ingredients. The Dairy Innovation Hub is investing in the future.”

Two students, Yihong Deng, of River Falls, and Kate Petersen, of Clear Lake, both food science and technology majors, will be conducting research this summer with Lewis on the projects specified above in a newly renovated lab space.

Lewis, in collaboration with UW-Madison, has also received funding from the National Dairy Council to research the use of a milk lactose-derived sweetener in various food products. The $163,000 two-year project, funded in February, will begin in September. The UWRF Dairy Plant is an asset to this research project as it will be used to create test chocolate milks and ice creams using this sweetener.

The Dairy Plant is undergoing nearly a $6.5 million renovation to modernize the 30-year-old plant and provide more effective teaching and training through the introduction of food products and security technology. Fundraising is continuing for the plant project. To learn more about fundraising efforts, email Julie Stucky in University Advancement at julie.stucky@uwrf.edu.

Dairy Products Evaluation Team competes

While at UWRF, Lewis has taught undergraduate courses in dairy manufacturing and food science with an emphasis on dairy processing and human health. She also is the coach for the Dairy Products Evaluation Team.

This past spring, the team competed at the 98th National Collegiate Dairy Products Evaluation Contest. The Wisconsin Cheese Makers Association hosted the event at the Wisconsin Center in Milwaukee.

The students evaluated six dairy products – 2% fluid milk, butter, cheddar cheese, vanilla ice cream, cottage cheese and strawberry-flavored Swiss-style yogurt. The team placed second in cheddar cheese evaluation and third in milk evaluation.

Team members Kaitlin Pescinski placed third in the individual cottage cheese evaluation and Carlie Nelson garnered a fourth individual award in milk evaluation. Nelson was also honored with the Joe Larson Merit Award which recognizes undergraduate competitors who best uphold the ideals of the contest including potential leadership, professionalism, mature behavior and an understanding of the importance of dairy sensory evaluation.

Nelson, of Stanley, who graduated in May with a bachelor’s degree in food science and technology, is working for Foremost Farms in their management trainee program in Marshfield.

Nelson said she enjoyed Lewis’s enthusiasm for dairy and her willingness to share her knowledge on the future of the dairy processing industry.

The hardest part of the competition was tasting eight samples right in a row because there are many different defects to learn for each product and they sometimes can be difficult to discern, Nelson said.

“It was very exciting for our team to place so well considering we were all so new to the competition and weren’t able to practice as much as other teams,” Nelson said. “It was also cool being the first UWRF team there.” 

Pescinski, of Shawano, who graduated in May with a degree in food science and technology emphasizing in dairy management, said Lewis is a “very dedicated and hardworking professor who provides quality lecture and lab experiences. She makes a great addition to the Food Sciences Department and the Dairy Innovation Hub.”

Pescinski said she was proud of the team as first-time competitors taking on universities from across the nation.

“A lot of the other universities spend many more semesters or even years preparing, but Dr. Lewis's teaching of the concept of the competition and dedication to getting us quality samples of the six different dairy products proved successful,” Pescinski said. 

Oddly, Pescinski, who is working as a landscape/horticulture intern for the city of Cottage Grove, Minn., placed in the creamed cottage cheese contest, a food she does not like. Dairy competitions can be difficult, she noted.

“There are so many defects that the general consumer would not be able to pick out and certain dairy products have a very subtle flavor or texture differences, while others have a very strong flavor that needs to be distinguished as a defect or not,” Pescinski said “It can also be difficult as a competitor to be good at all the products when they are unique in flavor, texture and appearance. It takes a combination of trained senses and memorization of how the scorecard works in reference to rating.”