Innovative Uses of Whey: From Byproduct to Biodegradable Solutions

The typical American consumes over 30 pounds of cheese annually, which generates about 270 pounds of whey per person each year. Whey, the liquid byproduct remaining after curds form, has traditionally been used in products like candy, pasta, baked goods, animal feed, and pharmaceuticals. However, recent research has focused on innovative uses for whey, aiming to develop eco-friendly products and reduce environmental waste.

One major innovation involves creating biodegradable plastics from whey. This addresses the increasing concern over plastic pollution by providing a sustainable alternative. Reactive extrusion, a process that involves melting plastic material and combining it with a chemical agent in a heating chamber, has been pivotal in this research. This method has led to the production of biodegradable plastic items, such as utensils, which decompose much faster than conventional plastics, thereby reducing their environmental impact and contributing to the mitigation of global plastic waste.

In another groundbreaking initiative, scientists have devised a way to produce biodegradable films from dairy and biofuel byproducts. By mixing casein, a milk protein, with water and glycerol (a byproduct of biodiesel production), and using carbon dioxide as an eco-friendly solvent, they have created water-resistant films. Carbon dioxide, a byproduct of glucose fermentation in ethanol production, enhances the water resistance of these edible films. This innovative application of CO2 not only repurposes waste from various industries but also offers a green solution for food packaging.

These biodegradable films present numerous benefits: they are glossy, transparent, and fully edible, extending food shelf life, protecting products from damage, and preventing exposure to moisture and oxygen while improving their appearance. By using renewable resources instead of petrochemicals, these innovations help reduce waste and environmental impact. Moreover, the edibility of these films adds a layer of functionality, particularly advantageous in food packaging where preservation and safety are crucial.

These advancements represent a shift towards a circular economy, where waste products are transformed into valuable resources. As research progresses, the potential applications of whey-based materials could broaden, offering more sustainable solutions across various industries. This approach not only promotes environmental sustainability but also creates economic opportunities by turning waste into wealth.
Innovative Uses of Whey: From Byproduct to Biodegradable Solutions

The fluid of buttermilk

Originally, buttermilk was the fluid remaining after cream was churned into butter. Buttermilk has been drink and used in American cooking since colonial times.

Dutch settlers in New York had it with their breakfast. Today, cultured buttermilk is made by adding acid lactic bacteria to milk, usually low-fat (1% milk fat) or fat free milk.

Lactic acid is a byproduct naturally produced by fermenting lactose. As the natural bacteria in the milk produce lactic acid at room temperature, the pH of the milk decreases and the casein precipitates, which cause the curdling or clabbering.

And that is why buttermilk is thicker than plain milk. Buttermilk is used in buttermilk biscuits and certain other baked goods primarily for flavor, although it can whiten, tenderize and leaven in some cases.

As a drink, buttermilk is tangy, highly flavored, and very nutritious. Like cream, buttermilk is thick and full bodies and like wine it fills the mouth with lasting, tart flavor.
The fluid of buttermilk

New uses for dairy byproducts

New uses for dairy byproducts
The average American consumes more than 30 pounds of cheese every year. Every pound produced creates an estimated 9 pounds of whey, the liquid byproduct that remains after the curds, or solids, coagulate.

Where does all the whey go? It's used in a range of products such as candy, pasta, baked goods, animal feed--and even pharmaceuticals.

Since its inception, ARS's Dairy Processing and Products Research Unit at the Eastern Regional Research Center (ERRC) in Wyndmoor, Pennsylvania, has investigated uses for whey and other dairy byproducts. Today, thanks in part to ERRC research, cheesemakers have markets for over 1 billion pounds of whey every year.

New research shows that whey can also be used to create eco-friendly products. For example, using a process called "reactive extrusion," food technologist Charles Onwulata supplements polyethylene--a common nonbiodegradable plastic--with whey proteins.

Reactive extrusion involves forcing plastic material through a heating chamber, where it melts and combines with a chemical agent that strengthens it before it's molded into a new shape. Onwulata showed that by combining dairy proteins with starch during this process, it's possible to create a biodegradable plastic product that can be mixed with polyethylene and molded into utensils.

Working with laboratory chief Seiichiro Isobe, of the Japanese National Food Research Institute, Onwulata created a bioplastic blend by combining whey protein isolate, cornstarch, glycerol, cellulose fiber, acetic acid, and the milk protein casein and molded the material into cups. Onwulata observed that dairy-based bioplastics were more pliable than other bioplastics, making them easier to mold.

Bioplastic blends can replace only about 20 percent of the polyethylene in a product, so resulting materials are only partially biodegradable. But Onwulata and his colleagues are currently applying this process to polylactide (PLA), a biodegradable polymer.

"Blending dairy-based bioplastics with PLA could eventually allow producers to make completely biodegradable materials," he says.

In a separate project, research leader Peggy Tomasula and her colleagues have developed technology to create biodegradable films from byproducts of both dairy processing and biofuels production. Tomasula found that combining casein with water and glycerol--a byproduct of biodiesel production--produces a water-resistant film that can be used as an edible coating for groceries and other products.

"We use carbon dioxide as an environmentally friendly solvent to isolate dairy proteins from milk, instead of harsh chemicals or acids, which can be difficult to dispose of," Tomasula says. Carbon dioxide is a byproduct of the glucose fermentation that is used to make ethanol, and she says it makes the edible film more water resistant.

The resulting food coatings are glossy, transparent, and completely edible. Like traditional food packaging, edible films can extend the shelf life of many foods, protect products from damage, prevent exposure to moisture and oxygen, and improve appearance. By using renewable resources instead of petrochemicals, the scientists can create more biodegradable products and reduce waste.
New uses for dairy byproducts
Source: Agricultural Research, May-June, 2007 by Laura McGinnis