As tired runners passed mile 23 of the London Marathon in April,
volunteers wearing blue 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 post-marathon cleanup job.Startup Notpla handed out sports drink capsules to London
marathoners in April. Consumers could eat these seaweed-based capsules
along with the liquid inside. Credit: Notpla.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,
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.
In Asia and Southeast Asia, some 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 sugar cane 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.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 who employ molecular gastronomy techniques make tiny, fluid-filled
pearls that are smaller-scale versions of these capsules. Sixty-five London restaurants that work with the 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 have reportedly started using the straws
this 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.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.An edible plastic film made from the milk protein casein
could replace the disposable plastic used to wrap cheese while providing
added nutrition. Credit: Headline Science/American Chemical Society.And instead of using carbohydrates, other groups
are working with proteins to make edible packaging. At the U.S. 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 are not the only consumers 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. 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.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 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. Credit: E6PR.
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 items that are the least likely to be recycled include seasoning sachets, food wrappers, straws, 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 used could 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.”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 eco-conscious 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.
Prachi Patel is a freelance contributor to
Chemical & Engineering News, the weekly newsmagazine of the American Chemical
Society.