Do produce shelf-life extenders actually prevent food waste? As produce suppliers and grocery store chains face increased competition and reduced margins, they turn their attention to finding ways to reduce fresh food waste.

About 12 percent of fruits and 10 percent of vegetables are wasted at the retail store, according to the NRDC. If one out of 10 heads of lettuce or clam shells of strawberries are being tossed because they spoiled prematurely, that’s a lot of money going to waste that significantly impacts profitability.

A Variety of Produce Shelf-life Extenders

A number of produce shelf-life extenders are on the market that try to address this problem but most of them don’t try to solve the problem at its source or they create greater issues across the supply chain.

Approaches like…

Coatings

Dipping or spraying a coating onto a product has been shown to help extend shelf-life on some types of produce, the most common example cited being avocados. By sealing the product with the coating, oxidation and respiration are slowed, extending shelf-life. There are, however a number of challenges associated with coatings including:

  • The impracticality for certain types of produce like lettuces and other leafy greens where it isn’t feasible to apply a coating. You can’t effectively seal a head of romaine lettuce or spinach leaves, for example.
  • Applying coatings to field-packed produce such as strawberries, lettuces or row crops would require a labor-intensive change to the field harvesting process as new equipment and steps would need to be managed in the field. With labor already in short supply, this makes them difficult or impractical to apply.
  • The still-unknown, actual shelf-life of the produce. Even by extending the produce’s shelf-life with a coating, there’s still an inherent mystery its remaining freshness. You still don’t know when it will spoil.

Hyperspectral Imaging

Hyperspectral imaging and photo analytics are another type of shelf-life extender that may reveal the current condition of the product, but it does not its previous history, handling or rate of aging. Again, this method does not convey the produce’s remaining shelf-life. You only get a snapshot of the current condition of the produce. If it experienced mishandling further up the supply chain, it may be aging at a much faster rate than if it was properly cooled and handled. You just don’t know. (We also have a Not Worth a Thousand Words about imaging applications for more detail.)

Pulping and Visual Inspection

Pulping and visual inspection are ways of identifying lagging indicators of freshness. That is, if you can look at a strawberry and see that it’s spoiling, well, it’s too late. And, these visual spoilage cues occur late in the supply chain – too late to do anything about preventing the waste.

Controlled Atmospheres

Controlling the atmosphere around some types of produce can be helpful. Managing ethylene is critical for handling bananas, for example. But not all produce reacts to ethylene. Controlled atmosphere environments (rooms or containers) can be of value but they still don’t tell you the condition of the produce and they can be expensive.

Not Bad, Just Not Complete

There’s nothing inherently wrong with using any of these produce shelf-life extender approaches except that they don’t focus on addressing the cause of food waste.

The primary cost of food waste has to do with harvest conditions and the impact of time and temperature on the produce from the moment of harvest.

Our research has shown that most of the impact occurs within the first 48 hours after harvest as produce sits in the field too long or if there are issues with cut-to-cool time or pre-cool efficiency. If a pallet of produce has to wait several hours to be cooled, it can lose several days of shelf-life.

You can’t tell the remaining freshness by looking at the produce. So, you may have one pallet with ten days of shelf-life and another with fifteen. If you coat both pallets, for example, you may extend the shelf-life, but you still won’t know what the remaining shelf-life is for each pallet.

What’s the Solution?

To monitor and manage the handling and condition of fresh produce, IoT sensors are unparalleled sources of information and require very little labor to apply and collect data. When you apply predictive analytics to IoT sensor data, from the time of harvest, this enables an accurate estimate of the actual remaining shelf-life of the produce We can know if a pallet of strawberries has 12 or eight days of shelf-life. With that knowledge, we can then ensure each pallet is shipped with sufficient freshness to meet the retailer’s requirements – preventing and eliminating waste.

This approach, which is what is used by Zest Fresh, can be applied to all manners and types of fruits and vegetables – from berries to leafy greens and row crops, whether they’re packed in the field or at the packing house – and it doesn’t impact the work and flow of the post-harvest supply chain as data collection and analysis is autonomous.

This approach can also be viewed as complementary to many of the produce shelf-life extenders described above. That is, Zest Fresh can work with products that are coated to know what that “extended shelf-life” value actually is or be used in controlled environment containers and provide growers, suppliers and retailers with the freshness insights they need to prevent waste at its source.

Read more about Zest Fresh and proactive shelf-life management.