Research expands ability to delay harvest, maintain fruit quality
By DAN WHEAT
Packers and processors are always looking for technological improvements to production lines, but one of the biggest advancements in the last decade has been use of a molecule to keep fruits and vegetables fresh longer.
That technology has improved efficiencies and grower returns, particularly in the apple industry, and is being considered for field applications. Among the other uses are reducing drought damage to rice in countries near the equator.
Use of the molecule, known as 1-Methylcyclopropene or 1-MCP, to slow ripening was discovered at North Carolina State University in the mid-1990s. Researchers were studying the natural ripening process of apples and found 1-MCP slows ethylene, a natural compound that causes fruit maturity and ripening.
AgroFresh Inc. of Spring House, Pa., patented it as SmartFresh, began marketing it to the apple industry in 2002. Most apple shippers have been using it since 2004, said Welcome Sauer, AgroFresh global vice president of horticultural products.
SmartFresh has been as significant a development for the apple industry as controlled atmosphere storage was in the 1960s, said Jim McFerson, manager of the Washington Tree Fruit Research Commission in Wenatchee, Wash.
"It's a paradigm shift that changed the nature of our industry for the better," McFerson said.
It complemented controlled atmosphere storage to improve the storability of apples, helping them maintain crunchy, juicy qualities longer for a better eating experience for consumers and better returns to growers, McFerson said.
It not only made fresh apples better but improved the quality of apples for processing into juice and applesauce, he said.
A lot of the original work on 1-MCP was supported by the Research Commission and done in Wenatchee at the USDA Agricultural Research Service Tree Fruit Research Laboratory by research leader Jim Mattheis.
SmartFresh is applied as a gas shortly after apples enter controlled atmosphere storage, biodegrades and is gone shortly after the application, said Sauer, who works in AgroFresh's Wenatchee service center and research lab and is former president of the Washington Apple Commission and a former apple marketer.
The treatment maintains apple starches and acids, retaining flavor, firmness and freshness, he said.
Studies of apples in grocery stores in 2007 by Eugene Kupferman, postharvest specialist at the Washington State University Tree Fruit Research and Extension Center in Wenatchee, showed SmartFresh actually increases firmness of apples during the sales season.
Packouts -- apples packed for fresh sales versus those culled for juice -- increased 8 percent between 2002 and 2008, according to the USDA, meaning better return for the grower on more of his crop, Sauer said.
USDA statistics show inflation-adjusted, grower-return prices for Red Delicious are 40 percent higher from 2007 to 2009 than from 1997 to 1999, Sauer said.
It isn't all due to SmartFresh, he quickly noted.
The apple market was depressed from 1997 to 2000 and the international economy was robust in 2007 to 2009, he said.
"In the past decade, Washington apple growers have retooled their industry using advances in growing techniques, rootstocks, greater varietal mix and quality-enhancing technologies to increase productivity, quality and returns," he said. "SmartFresh technology is one of the many improvements.
"As apple marketers, we have always known that the single biggest marketing weapon is fantastic eating experience, especially in the form of crunch. The industry has delivered crunch and consumers have responded with increased demand."
AgroFresh, owned by Dow Chemical Co.'s Dow Agro Sciences division, is testing Harvista, a 1-MCP technology sprayed on apples about one week before harvest to delay it, Sauer said. Harvista delays ethylene from softening the bond between apple stem and limb. The idea is to give growers more time to harvest instead of being rushed when fruit ripens all at once, he said. It means better labor management and better fruit in the bin for storage, he said.
"We're still a ways away from launching a commercial product. There's great promise with it for Bartlett pears and Gala apples," he said.
SmartFresh is used in pears and plums. It delays banana ripening two to three days but is not widely used with bananas, Sauer said.
"We can treat tomatoes at pink stage and hold them an extra 10 days easily, but the industry moves product so fast that it's been hard to break in," he said.
SmartFresh is used on kiwifruit in Chile. EthylBloc, a sister product, is used a lot on cut flowers shipped into Florida from Colombia and Kenya, he said.
AgroFresh is working with Syngenta on 1-MCP-based Invinsa for rice, cotton, corn and soybeans to allow them to grow and produce high yields under drought stress, Sauer said.
Ethylene shuts down a plant under heat stress and Invinsa counters that.
Researchers have seen up to a 10 percent yield increase in rice under heat stress in countries near the equator, he said.