RediRipe CEO Bob Klein in a pear orchard with his stickers

So When Is Fruit Ripe?

August / September 2008 By: Eric Billingsley Volume 6 Number 4

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How do you know when a piece of fruit is perfectly ripe and ready to eat? Not too hard, not too soft, and when you bite into it, it's certain to be an experience that leaves you wanting more. Some people knock on the fruit, smell it and analyze every square inch of it to determine ripeness. The only problem is these techniques are not an exact science. You might be lucky, you might not.

Enter Bob Klein, CEO and co-founder of a startup named RediRipe LLC in Albuquerque. He and University of Arizona researcher Mark Riley have developed a thumbnail-sized flat sticker that will tell you if the fruit is ripe.

The patent-pending device self-adheres to individual pieces of fruit—€”just like a Chiquita sticker—€”and captures the plant hormone, ethylene, as it is emitted during the ripening process. The sticker remains white if the fruit is un-ripe, and turns blue when it reaches optimum maturation.

"It actually wasn't a very ingenious idea," says Klein. "I just thought there must be a better way to tell if fruit is ready to eat." It can potentially be used on all ethylene-emitting produce such as apples, pears, peaches, avocado, melon and tomatoes.

Fruit marketers are eagerly awaiting the RediRipe sticker. They say it will give consumers a foolproof way of choosing certain varieties of fruit, cut down on waste in the industry and increase consumption.

Klein says he and Riley have been exploring possible uses of the technology for homeland security, strange as that may seem. The RediRipe sticker could be used for detecting viral terrorism attacks on fruit imported to the United States. Research conducted at the University of Guelph in Canada indicates there are spikes in ethylene in diseased fruit, he says. With tobacco, for example, a disease does not fully set in for 72 hours. But within the first 24 hours of contamination, ethylene jumps.

"There might be reason to move forward with research on tobacco, tomatoes and flowers," says Klein. "The goal would be to develop a tool for quick understanding of a pathogen attack and the exact pathogen involved."

"Our industry has been dreaming of something like this for many years," says Kevin Moffitt, president of the Pear Bureau Northwest, a non-profit marketing organization for the pear industry. "The sticker would allow us to overcome consumer reluctance, because if consumers don't know how to properly select or use the fruit, they won't buy it."

RediRipe was formed in 2004. Klein, now a retired psychologist, says he came up with the idea because he was curious about the psychology behind consumer's fruit choices. Not having a background in chemistry, he spent several years searching out a scientist to develop the sticker. He teamed up with Mark Riley, a professor in the department of agricultural and biosystems engineering at the University of Arizona in Tucson. RediRipe has an exclusive licensing agreement with the university for research and development of the sticker.

The two secured more than $200,000 in R&D funding from the Washington Tree Fruit Research Commission, a grower-sponsored organization that provides seed funding for research in the industry, and the USDA's Small Business Innovation Research Program.

"The tree fruit industry jumped on it," says Klein, adding after going through a competitive proposal process, "One of their first questions was, —€˜When can we get this?'"

RediRipe has also received in-kind research and development support from the New Mexico Small Business Assistance Program at Sandia National Labs. Technology Ventures Corporation in Albuquerque helped the company develop its business plan and present at its 2007 Equity Capital Symposium.

Most of the research and development, to date, has focused on the sticker's use on pears and apples. The idea is to sell the device to producers and/or packinghouses. One sticker would be placed on every piece of fruit before shipment to retailers, and it may eventually be sold directly to retailers.

The sticker works, according to Klein, but needs further field-testing and some refining in the areas of stability and predictability of change.

"The market is just salivating for us to finish," says Klein. "People know what this is going to do for them. It's not a complicated machine or something."
Pears are one of the top 10 selling fruits in supermarkets nationwide, according to Moffitt. Some pear varieties change color when they ripen, but one of the most popular types of Anjou pears does not.

"One of the main barriers to more movement of pears is the fact that most consumers have never eaten a truly ripe Anjou pear," says Neil Galone, vice president of marketing for Diamond Fruit Growers in Hood River Valley, Ore. "And they usually get it wrong because pears ripen from the inside out."

"The advantage of the sticker is it kind of dummy-proofs it," he says. "If I can get a truly ripe pear into consumer's hands, then their eating experience will be better and they will want to purchase more."

And the sticker may have broader implications, according to Jim McFerson, manager of the Washington Tree Fruit Research Commission. He says understanding the biochemistry of maturation is key for developing ways to preserve the quality and longevity of fruit with temperature, chemicals and other methods. It can also cut down on waste in the industry.

"If you can measure it, you can manage it," says McFerson. A ripeness indicator can also make it easier for producers to decide whether to ship fruit to supermarkets or manufacturing facilities for use in products like juice.
"All of this returns dollars to our growers," says McFerson. "Bob's sticker is not a magic bullet, but it is part of the larger picture."

Klein says numerous investors have expressed interest in the technology and RediRipe is receiving inquiries from fruit growers and retailers worldwide. The company is applying for additional research and development funding from the New Mexico Small Business Assistance program at Los Alamos National Laboratory.

Eric Billingsley is a freelance writer based in Albuquerque.