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Food Science

The time is now for edible packaging

Companies are striving to address the problem of plastic pollution by developing edible wrappers, tableware, and more

by Prachi Patel, special to C&EN
January 26, 2020 | A version of this story appeared in Volume 98, Issue 4

 

A runner reaches for a lime-sized drink capsule filled with yellow liquid, held by a hand wearing a blue plastic glove.
Credit: Notpla
Start-up Notpla handed out sports drink capsules to London marathoners in April. Users could eat these seaweed-based capsules along with the liquid inside.

As tired runners passed mile 23 of the London Marathon in April, volunteers wearing blue plastic gloves offered them squishy, lime-sized bubbles to pop into their mouths. The edible drink pods, containing a sip of a sports drink, replaced thousands of cups that runners typically would have thrown onto the road, choking storm drains and creating a massive postmarathon cleanup job.

Called Ooho, the capsules encase liquid in a waterproof film made from seaweed. Users can gulp the drink and swallow the packaging. But if they choose to spit out the film, it will biodegrade in 4–6 weeks without a trace, according to its maker, London-based start-up Notpla.

Notpla wants its material to reduce the world’s plastic footprint. The company is part of a small but growing number of innovators and entrepreneurs who are looking at turning foodstuffs like seaweed, potato starch, and milk proteins into edible packaging and tableware. Some edible films, wrappers, and straws have found a small, specialty market and are starting to get attention from large food and beverage companies.

The idea of edible packaging has been around for a while, but the time is now ripe for it to take hold in the food industry. Concern about plastic waste is growing globally, and the most common items that wind up as litter and pollute the ocean are linked to food: wrappers, straws, cutlery, bottles, and more. Edible packaging offers hope, but with a healthy side of hype. For instance, plastic is hard to beat for packaging: it is cheap, light, and versatile and has excellent mechanical properties. Meanwhile, eating a food’s wrapper raises hygiene concerns—and not everyone wants to chase their burger and drink with the burger wrapper and straw.

Yet in the right contexts, edible packaging could help wean us from plastic. It comes from renewable sources. And even if it isn’t something people actually want to eat, it would still be hyperdegradable, disappearing much faster than single-use plastics or even compostable bioplastics. According to Transparency Market Research, a global research firm, demand for edible packaging could increase on average 6.9% yearly until 2024 and could become a market worth almost $2 billion worldwide.

“Edible packaging will find its place,” contends Carol Culhane, a food scientist and a member of the Institute of Food Technologists. With threats of plastic pollution escalating, she says that could happen soon.

Something to chew on

Nature does edible packaging well. Apple and grape skins protect the fruit from microbes and the environment. Humans have also been making consumable packaging for decades: sausage casings made of collagen and cellulose, and ice cream cones are examples. People in some parts of Asia use plates and bowls made of banana leaves that later become cattle feed.

But plastics such as polyethylene and polystyrene offer unmatched convenience and extended shelf life. They block germs, keep potato chips crisp, and protect berries shipped hundreds of kilometers. They can also be shrink-wrapped around a cucumber to quintuple its shelf life.

Bioplastics made from cornstarch and sugarcane are sold as more ecofriendly—renewable, though not edible—alternatives. But they can be just as bad as petroleum-based plastic for the environment, sitting around for hundreds of years in a landfill or floating in the ocean without breaking down. Edible packaging takes biodegradability to the next level; the same properties that make the materials edible also make them hypercompostable.

To make edible proxies for plastic, most researchers have turned to strong, natural polymers extracted from plants. The ideal edible packaging would be made from a mix of proteins and carbohydrates, the bases of biological polymers found in plant tissues. These polymers can be effective barriers to oxygen and liquids that spoil food, Culhane says. Food-grade plasticizers such as glycerol and sorbitol can make edible polymer films flexible and stretchy.

Blue straws sit on a surface.
Credit: Jessica Marshall/C&EN
Loliware straws made of algae and seaweed behave like plastic for 24 h once wet but degrade entirely within 2 months, the company says.

Companies developing such packaging keep their exact recipes and processes under wraps. But we do have a few clues. Notpla and several other edible-packaging makers prefer seaweed as their carbohydrate source. Notpla’s Ooho capsules begin as frozen, mouthful-sized balls of their desired contents, which a machine dips into a calcium chloride solution followed by a solution of the seaweed extract sodium alginate. Calcium ions cross-link the alginate to make calcium alginate fibers that form a waterproof membrane. Chefs that employ molecular gastronomy techniques make tiny, fluid-filled pearls that are smaller-scale versions of these capsules. Sixty-five London restaurants that work with online food-delivery company Just Eat are now offering ketchup and other condiments in Ooho sachets, and Glenlivet sold whisky cocktails in them at London Cocktail Week in October. According to a patent that Notpla filed in 2018, the firm can now extrude the waterproof film first and then fill it, paving the path to packaging dry foods like chips and pasta, an approach the company is testing.

New York–based Loliware is turning alginate from seaweed and agar from red algae into flavored straws that, unlike paper straws that get soggy, behave like plastic for 24 h once they become wet. You can eat them if you like; regardless, they will degrade in the environment within 2 months, according to the company. Marriott Hotels and alcoholic-beverage giant Pernod Ricard reportedly started using the straws last year, and Loliware plans to make up to 30 billion of them by the end of 2020.

Indonesian company Evoware has tested its edible seaweed-based packaging as a burger wrapper and is now selling it in small quantities for instant-noodle seasoning sachets and coffee pouches. In addition to cutting plastic use—Indonesia is the second-biggest source of ocean plastic waste—Evoware hopes to provide income to local seaweed farmers.

As consumer demand for better-for-the-planet packaging options increases, so too will the demand increase for manufacturers to meet these standards.
Melina Romero, trend insights manager, CCD Innovation

Some companies and academic researchers are trying carbohydrates from sources other than seaweed, using starches from potatoes, for instance, to make cupcake holders, transparent films, and food bags.

And instead of using carbohydrates, other groups are working with proteins to make edible packaging. At the US Department of Agriculture, chemical engineer Peggy Tomasula has made transparent films from the milk protein casein, which “behaves much like plastic and is a way to utilize a product of the dairy industry,” she says.

The films—made of tangles of calcium caseinate protein, with the citrus polysaccharide pectin added for strength and glycerol added as a plasticizer—are 500 times as effective at blocking oxygen as traditional plastic wrap, according to the USDA. Tomasula is now partnering with a few private companies to develop products made of these films, which could package powders or replace the disposable plastic films that wrap cheese slices and sticks.

Humans aren’t the only consumers that researchers are targeting for edible packaging. Mexico-based E6PR makes six-pack rings using fibrous wheat and barley remnants from beer brewing. They can fully degrade in the ocean in a few months, reducing the chances that the rings will ensnare marine animals or harm them if eaten.

Is the idea garbage?

Asian rice candy comes up frequently in edible-packaging discussions. Kids love to pop the gooey candy, which comes in a thin, edible rice paper wrapper, into their mouths. But the rice paper package is also wrapped in an outer layer of plastic or wax paper. That double layer illustrates a conundrum with edible packaging or tableware: if consumers are expected to eat it, it needs to be protected from dust, germs, and other contaminants.

Another hurdle is getting the customer comfortable with “the idea to eat something that conventionally is thrown away,” says Stefano Farris, food-packaging researcher at the University of Milan. That’s a big change in mind-set, he says.

There are ways to make this idea easier to swallow, though. Promoting nutritional value is one way. Evoware says its packaging is naturally high in fiber, vitamins, and minerals, and the USDA’s casein films would add a boost of protein to a person’s diet. Packaging could even add to the pleasure of eating the product, the Institute of Food Technologists’ Culhane says. “Think about Rice Krispies that snap, crackle, and pop,” she says. Packaging for cereal or crackers could be dry and snappy like that to add to mouthfeel.

We use packaging to protect food. We don’t use food to protect food.
Bruce Welt, chemical engineer and food-packaging researcher, University of Florida

Technical challenges still need to be overcome, though, before edible packaging can enjoy more widespread use. Moisture and heat remain nemeses of edible films, making long-term storage and transport a hurdle. Noodle packets and tea bags can be made to dissolve after being plopped in hot water, but they can’t get gooey beforehand. The casein films “can’t handle high humidity and will start gluing together in a hot warehouse,” Tomasula says. The USDA team is working to address the casein film’s moisture-stability problem.

Researchers and food industry experts all agree that edible packaging will require an outer layer, just like ice cream cones are wrapped in paper and sold in a box. Those outer materials could also be made from compostable or sustainable materials. But plastic packaging isn’t going away anytime soon, says Bruce Welt, a chemical engineer and food-packaging researcher at the University of Florida. “We use packaging to protect food. We don’t use food to protect food.”

The sustainability of edible packaging is also fuzzy. While it’s certainly a better option than using plastic, the materials or natural resources used to produce it are an important consideration, says Melina Romero, trend insights manager at CCD Innovation, a strategic consulting agency for the food and beverage industry. The materials shouldn’t compete with food sources or have a high environmental cost.

A higher price for such packaging compared with its fossil fuel–based counterparts could also limit its marketability, Farris points out. Loliware, for instance, plans to make its edible straws competitive in price with paper straws, which cost much more than plastic ones.

A six pack of beer is held together by a tan, cardboard-like holder instead of standard plastic rings.
Credit: E6PR
A six-pack ring made from the wheat and barley remains from beer brewing could cut plastic waste and could be eaten by animals if it ends up as debris.

Perfect for the right use

The developers of edible packaging recognize that plastic’s virtues are hard to duplicate. They do not intend to replace plastic but want to make a dent in its use. Our modern plastic-wrapped world offers many opportunities.

According to research by the Ellen MacArthur Foundation, the food-related items that are the least likely to be recycled include seasoning sachets, wrappers, and coffee cup lids. All these single-use items could be made from edible or hypercompostable materials—as could the boxed drink pouches and snack packs lining grocery shelves and the packets used in meal kits. Wraps for fast food and fresh goods are another prime application. “We have a lot of opportunity with beverages and snacks to address alternatives to their current plastic packaging,” Romero says.

Besides what’s in an edible package, where the package is meant to be used will be critical to its success. In October, design studio PriestmanGoode took a flight of fantasy with an airplane meal tray made of sustainable and edible materials. The tray itself was made of coffee grounds, and it held wheat bran plates for entrées, a coconut wood spork, a dessert lid made of an edible wafer, and seaweed-based capsules for sauces and milk. The point was to drive home the need to reduce the 5.7 million metric tons of plastic waste that passenger flights produce every year.

Air travel, ocean cruises, and space travel are indeed prime markets for edible ware, Culhane says. The extra cost of the packaging is negligible compared with the price of a ticket for these trips. Outdoor recreation is another high-value market; consumers might be willing to pay a little bit more for an environmental benefit. “People who like to go camping and leave less packaging behind could eat it or throw it into the campfire,” Culhane says. And while these markets might be niche, she says, “there’s nothing wrong with a long-standing niche at all.”

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When the situation is right, people will get over the idea of eating packaging, experts say. “There are conditions in which consumers are willing to not think about the yucky factor,” says Sylvain Charlebois, a food business researcher at Dalhousie University. “Like when you’re running and need to drink, putting a ball of water into your mouth where you eat the film along with water is fine.”

A combination of clever technology and savvy marketing might be the recipe for success for edible packaging. Five years ago, no one knew Burger King would be selling plant-based burgers, and then in 2019, they were added to the fast-food chain’s menu. Consumers had known about the health and environmental benefits of meat substitutes for years. But garnering a wide audience took an affordable product that emulated the taste and texture of meat plus a huge advertising push.

Food industry trend experts point to the growing base of consumers who are ecoconscious yet demand convenience and are willing to pay for that. “As consumer demand for better-for-the-planet packaging options increases,” Romero says, “so too will the demand increase for manufacturers to meet these standards.” The only limits for edible packaging, she adds, are creativity and innovation.

 

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Prachi Patel is a freelance writer. A version of this story first appeared in ACS Central Science: cenm.ag/ediblepackaging.

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