Ethylene Management Breakthroughs

It’s also interesting to note that ethylene gas is a byproduct of combustion engines, so using electric forklifts rather than gas-powered ones can help reduce the presence of the gas. Trucks and gas forklifts should not be left idling near fresh produce, and proper ventilation of storage areas is another important factor.

Turning to Materials Science Solutions

Beyond these process lessons and improvements, there have been several advances made in the field of ethylene management over the years.

Modified Atmosphere Packaging (MAP) is a technique in which fruits and vegetables are allowed to respire in a more enclosed environment, to slow their respiration rate. Membranes are used to allow some carbon dioxide to escape and some oxygen to enter. But for many ethylene-producing foods, MAP becomes a more tricky issue, as ethylene buildup can occur. Allowing the growth hormone to stay while lowering the oxygen is like breaking and accelerating a car at the same time. This generates confusion in the fruit’s metabolic processes. Some refer to this as “fruit freak-out” as the food exhibits dramatic respiration levels and rapid degradation upon being removed from its controlled atmosphere and forced to acclimate to new environments.

Ethylene inhibitor 1-methylcyclopropene (1-MCP) is a gaseous ethylene inhibitor used in enclosed commercial environments, such as inside truck trailers, coolers. and storage facilities. 1-MCP is a chemical application that binds to the ethylene receptors on fruit surfaces. The danger here is that in many cases 1-MCP can permanently stop fruits and vegetables from ripening. That may be good for crunchy apples, but it’s less desirable in the instance of hard avocados, for example. Blocking ethylene receptor sites also involves chemically spraying the produce, which can be unpopular with consumers. And it doesn’t stop ethylene peel damage, like scald on pear skin, nor does it halt ethylene’s involvement in the pathways of rots and molds in wounded fruit.

Ethylene-scrubbing filters, usually containing the inorganic (but toxic) compound Potassium permanganate, may also be used within cold chain storage areas as an oxidizing agent to convert ethylene into carbon dioxide and water. When using these filters, it’s crucial for the oxidizing process to be fully complete as incomplete oxidation may potentially result in undesirable byproducts. And while there are various scrubber solutions on the market—some use Potassium permanganate pellets, others have ozone-based systems, and still others offer photocatalytic oxidation where UV light is used as a catalyst to break down ethylene—it’s important to keep in mind that most all cannot be used in-store or at home, where more than 60 percent of waste occurs.

Recent materials science developments also provide new and effective deterrents against ethylene-induced ripening.

For example, It’sFresh! has developed an ethylene adsorption sheet capable of extending natural shelf life and the quality of fresh produce by up to three extra days in-store and at home. The paper-thin sheet, which can be inserted into fruit and vegetables crates and containers, includes a patented mixture of minerals and clay designed to capture ethylene and minimize ripening and other damaging effects. The sheet acts as a “scavenger”-type method that seeks out, adsorbs, and traps nearby ethylene molecules as they are released at any stage of the supply chain from immediately upon postharvest through to the consumer’s home. The technology is effective in all temperatures and atmospheres, and can be used in harmony with MAP.

The produce and retail industry’s efforts to extend shelf life will obviously have great commercial benefits. Shelf-life extension increases store availability of fresh produce, offering retailers more freedom to sell their stock, thereby reducing loss of inventory and increasing sales.

Ecological sustainability is another added benefit of using the latest materials science solutions to delay the ripening process. After all, less waste means greater efficiencies and an overall reduction of agricultural inputs, such as water usage and transport emissions, over time.

A Team Effort

Certainly, the problem of food waste will not be solved by any single technology, law or campaign. This global issue will require a multi-faceted, global solution with contributions from scientists, regulators, academics, businesses, and consumers.