Can ‘touchless’ preservation extend shelf life without adding ingredients?

In the current clean label era, chemical-sounding preservatives are increasingly demonized, yet consumers remain unwilling to compromise on shelf life – creating a conundrum for food companies that want to keep food fresh longer without adding another ingredient to the label.

Simply going without preservation isn’t a viable solution given that currently about a third, or 1.3 billion tons, of food produced annually is wasted annually, with spoilage and expiration playing major roles across the supply chain, according to the World Resources Institute. While the bulk of this occurs in consumers’ homes, upwards of 20% is lost at the retail or food service level, according to the UN Environment Programme, and about 14% is lost during harvest, storage and transportation before it reaches retail, according to the Food and Agriculture Organization of the United Nations.

This has created a need for preservation technologies that can protect food, but which are not added as an ingredient, and therefore appear on labels.

A small but growing group of startups is answering this call with a range of “touchless” options that extend shelf life by treating the environment around a product, rather than adding a preservative directly to the product.

This category includes BioBlends, which uses gas-based compounds derived from bacteria to extend shelf life without the additives – an advancement that helped the startup become a runner up in the Global Food Tech Awards Americans heat this year.

Two other startups are pursuing the concept from very different directions: food-tech startup Onza Corp., which developed a way to capture and deploy ozone in a solid state around food, and Natures Frequencies, which created a US patented Food Freshness Card that can be placed in storage environments and which the innovators say can keep food fresher up to 50% longer than without.

Onza ‘harnesses the power of ozone’ in packaging to extend shelf life

Onza’s approach starts with a familiar antimicrobial that is already approved by FDA for direct contact on food – ozone – but in an unfamiliar format: a solid state.

“Ozone is in the stratosphere and may be the best oxidizing gas in the world. It pokes holes in bacteria, yeast and mold,” and is often used to “wash” a space by filing it with the gas to kill microbes, explained Stephen Goldman, chief science officer at Onza.

But, while effective, this technique is very expensive, he acknowledged.

“The downside is you need a huge pallet-sized ozone generator that will probably cost you about $70,000 and source of oxygen and electricity. So, it is very intensive to produce, but only lasts about 10 to 20 minutes as a gas before it reacts with something and is gone,” he said. “That means you can’t use it in a farm field or take it where you want to use it.”

Until now.

Onza has developed a proprietary technology to trap ozone gas in clathrates, or molecular cages made of salt or sugar, which are generally regarded as safe in hundreds of food, according to Goldman.

The captured gas can be sold in bulk and mixed with water to use as a rinse in the field or in processing plants, or placed in sachets that can be adhered to clamshells or bags with produce, where Goldman said they far outperform absorbent pads or desiccant pads.

“The current solutions are not active, so they will claim a benefit in shelf life by removing water, or by removing ethylene, which is the gas that fruit uses to ripen. Neither of those solutions actually kill organisms,” he explained. “Our solution is hydroscopic, meaning it will absorb moisture, so it can replace those, but also additive in that it will actually inhibit ethylene, so it delays ripening.”

Tests by the company show blueberries remained fresh by consumer standards by up to 20 days – reducing post-harvest losses by as much as 40%, which he said translates to 40% more revenue.

The ozone also improves the quality of the food, Goldman said. For example, in blueberry trials, the color and firmness stayed better for longer.

Over the past year, the company has de-risked its product, scaled about 20x from the initial prototype and is undergoing trial with a couple of “behemoth companies,” Goldman said. But, he added, to meet anticipated demand the company will need to scale an additional 100 to 200 times.

“It is a very steep acceleration in our manufacturing capabilities that we are currently undergoing,” but should be completed “on a timescale of months, not years,” he added.

Natures Frequencies offer flexible applications

Like Onza, Natures Frequencies’ The Food Freshness Card can be used at any point in the supply chain to extend shelf life and prolong freshness of produce and bread, according to the company.

With three US patents and 14 international awards, including the Gold Medal Edison Award, the laminated cards have a “specialized holographic medium programmed with longitudinal electromagnetic waves” with different frequencies that slow the growth rate of mold and bacteria, said RJ Hassler, who developed the card with his father Rick.

“It works of ambient electromagnetic waves, similar to an RFID chip,” so it doesn’t need an outside power, he said.

Nor does it need to touch the food. Simply place it the storage room, in a refrigerator, transport vehicle or on store shelves to protect the surrounding food, he added. The protection zone depends on the size of the card.

According to the company, the cards can extend shelf life by 50% or more.

In a three month case study conducted at Bridgewater State University where 36 Food Freshness Cards were installed in the commercial kitchen facilities, there was zero spoilage compared to a loss of about $500 per month prior to the installation, according to the company.

More recently, the company has installed the cards in supermarket chains where it has tracked shrink reduction of 26% to 40%, “which is really just a profit issue,” said Mike Hassler, RJ’s brother.

He added that customers typically recoup the cost of he cards within months, while the cards themselves are designed to last about three years.