Fresh fruit is available as a diverse, delicious, and healthy option for most American consumers. Some fruits are only in stores on a seasonal basis, but many are found throughout the year thanks to a collection of technologies that enhance storage life and quality, allow energy-efficient shipping, and prevent food waste. Within the post-harvest portfolio, there is one particularly interesting and effective technology called SmartFresh™ and since 2003 it has revolutionized the fruit industry’s ability maintain just-picked quality all the way to the consumer. It has just passed the 20-year mark since commercialization by AgroFresh and it remains a top choice for preventing waste and keeping apples – as well as other fresh produce – crisp and flavorful year-round.
With fresh fruit, the basic challenge is how to manage the ripening process. The crops need to be kept on the tree/vine/bush long enough to achieve full flavor, but then it’s somewhat of a race to get it to the consumer before the quality begins to break down and/or the fruit ends up as food waste. Cold temperature during storage or shipping buys time, but the dynamics of the ripening process often come down to ethylene, a natural chemical which plants themselves make to control various processes, including ripening, flowering, and senescence. SmartFresh™ puts the ripening process “on hold” so that softening and ripening occur much more slowly as part of the produce’s normal freshness cycle. You have probably experienced the way that ethylene speeds up the rate at which avocados ripen on your counter if they are next to bananas. That is because both fruits produce ethylene, which accelerates the ripening of each.
The twenty-year-old, SmartFresh technology mentioned above works through control of ethylene signaling, with its first major application in the apple industry. Over the past two decades, it has made it possible to deliver millions of tons of high quality, crisp, and flavorful apples to the grocery store, and be enjoyed at home, that might otherwise have been wasted. There are now additional applications of this technology in more than 30 other crops including mangoes and limes, stone fruit, bananas, and avocados.
The SmartFresh story is an excellent example of the synergies that can come from public/private connections between agriculturally focused land grant universities and the private sector. This particular technology came out of research conducted by two scientists at North Carolina State University in 1994: Edward Sisler, a biochemist and Sylvia Blankenship, a horticulturalist. They discovered a relatively simple, volatile, non-toxic solution called 1-Methylcyclopropene (1-MCP), which binds to the ethylene receptors in plants to slow the natural ripening process. For apples, that means that the fruit stays crisp and juicy and retains higher vitamin and flavonoid concentrations. As Dr. Blankenship describes in this interview, this was a surprising finding, but it was clear that it could have major applications in the fruit and vegetable industry. The University filed patents and those were licensed by Rohm & Haas. In 1996, the AgroFresh division of that company was founded to do the work to commercialize SmartFresh™ and get it registered through the EPA. The first commercial launch in Chile, the United States, and New Zealand was in 2003 and it is now approved for use in more than 50 countries and is used in multiple crops, including pears, plums, avocados, mangos, and stone fruit. AgroFresh recently became a private company under the Paine Schwartz Partners (PSP) umbrella, a sustainable agricultural technology company.
The Reasons We Can Enjoy “An Apple A Day”
SmartFresh™ plays a critical role during storage. In North America, apples are harvested over a few months in the Fall and, prior to the introduction of refrigeration in the early 1900s, they were only available for a short period, which was extended slightly by placing them in a “root cellar” or “ice box.” Apples lasted longer in refrigerated storage, but their quality declined within a few months until the introduction of a technology called “controlled atmosphere,” or “CA storage,” in the 1960s. That system is used in sealed, refrigerated storage facilities where the air supply is altered to have extra carbon dioxide and very little oxygen. Under those conditions, the apples have lowered metabolic activity and can stay fresh and flavorful for months. However, if there is much ethylene present in that CA storage, the apples become “mealy” and generally less desirable. The song “One Bad Apple” made famous by the Osmonds in the 1970s had the famous line, “one bad apple don’t spoil the whole bunch, girl,” but that is not accurate when it comes to real apples. A rotting apple generates a great deal of ethylene and, although many measures are taken in the orchard and on the way into storage to prevent decay, some occurs, and the effect is a decline in the firmness and juiciness of the rest of the apples. SmartFresh™ is now used to prevent that outcome on around 75% of U.S. apples. This means that apples can be stored for longer time periods and still have the taste, texture, aroma, and health benefits they did straight from the tree.
There are now many additional applications of SmartFresh™ around the world. A field-applicable version of 1-MCP called Harvista 1.3 SC