Private research program focuses on practical issues

Researchers in the public sector, including the U.S. Department of Agriculture (USDA) and Washington State University (WSU), are addressing basic industry needs, he said.

And what the industry needs is more information on fruit quality enhancement, tree maintenance, variety selection, integrated pest management, storage regimes for existing varieties, and biocontrol agents for postharvest diseases. It also needs rapid detection methods for fruit pathogens and an on-line nondestructive quality sensor, Reed suggested during a seminar he gave at WSU's Tree Fruit Research and Extension Center in Wenatchee.

Practical

Stemilt's own research and development department focuses on practical issues. Its customers are Stemilt's growers and employees, and the people it sells fruit to. "There are a lot of people out there with questions they want answered," Reed said.

In response to public concern about agricultural chemicals in the late 1980s, Stemilt developed an environmental awareness program called Responsible Choice, which is based on the European integrated fruit production (IFP) system. Information to develop the program came from many sources, including the USDA and state institutions.

Reed said Stemilt has tried to assimilate that knowledge into a package that can be used to promote environmental awareness and target buyers who respond to those issues.

Quality assessment

Stemilt's research and development department is involved in quality assessment. The normal procedure is to test incoming fruit for pressure, sugar and starch levels, and physiological disorders to assess how it can be stored.

The fruit is also assessed for size and color. When apples arrive at the warehouse from the orchard, a sample of one full lug per 16 bins is taken and run over a custom grader. Fruit is returned to the bins so that the grower is paid for the fruit. Information on size and color goes into the warehouse's inventory forecast, so that the marketing department has an idea of the size and grade of apples in a particular storage room even before the fruit has been presized. This allows the marketing department to plan ahead and maximize returns to the growers, Reed said.

Intranet

Stemilt is setting up an Intranet, based on its grower list. It will include databases with spray records, weather data from 45 weather stations, and packout and production statistics. The grower acreage was surveyed using a Global Positioning System, so that a particular piece of land can be tracked from year to year even if the grower number changes. This will enable the company to identify commonalities across growers in terms of problems or production, to predict what future production will be, and to develop future marketing strategies, Reed said.

Filter

His department also acts as a filter for new products that are sold to the industry. "There are so many products available on the market, but if all these products were to work, I guarantee the industry would not have any problems, and part of our function is to ascertain which of these products are worth being studied and pursued, and put into practice if they prove fruitful," he explained.

Successes

Some new developments have proven successful, such as modified atmosphere packaging (MAP) for cherries, which Stemilt uses routinely now to maintain and preserve the quality of cherries. The packages have been improved with new membranes to the point that they are "true smart bags," Reed said.

The company bought 28 gas flushing and sealing machines for two of its plants at a cost of $250,000.

Stemilt also is using two systems for testing cherry firmness, one called a Momentum Transfer Generator (MTG) and a robotic method called FirmTech. Reed said the FirmTech seems more consistent, and software has been added so that it can determine size as well as firmness of cherry samples.

Methyl bromide

In 1994, Stemilt tested recycling of methyl bromide, which is being phased out because of its effect on the earth's ozone layer. The recycling system involved using zeolite to capture methyl bromide from cherry fumigation chambers instead of venting it into the atmosphere. The methyl bromide was then desorbed from the zeolite and pumped back into the fumigation chamber to treat the next batch of cherries. Between 90 and 95% of the methyl bromide could be recycled.

"This had great potential," Reed said.

However, it has not yet become a commercial option, partly because of liability issues concerning the recycling of the product. Methyl bromide manufacturers have suggested that the recaptured methyl bromide be returned to them to be checked before being reused. There are also questions concerning the process that would be used to certify such a recycling system is working properly.

Eliza test

An Eliza test for TBZ (thiabendazole) was developed to test residues on apples, following complaints about residues on apples that were shipped to Japan two years ago. The test could detect residues in parts per billion and could help show packers if apples were picking up residues from the packing equipment. Since the Washington State industry is no longer shipping apples to Japan, the test is not being used.

Promising developments

Some new procedures that show promise include postharvest biocontrols, devices for testing apple firmness nondestructively (see "Sensor monitors firmness of apples in CA storage," page 25), and a method of cleaning dump tank water based on electro-coagulation. Reed said the latter is effective on a small scale, but questions remain concerning the cost on a commercial scale, how frequently it can be used, and if it can be scaled up successfully.

Not successful

New procedures that have not been successful include use of ozone in the dump tank to purify the water. Reed said the process works, but, in practice, it is impossible to put enough ozone in the system to keep up with the need in the initial dump tank, where debris from the orchard is brought in with the fruit. He said it may be more practical to use it in flume systems where the water is usually cleaner.

Stemilt also tested an internal defect sorter that did not work.

"The claims some people make don't stand up when you take a close look at them," he warned.

Reed said what he looks for when people pitch products to him is good data and a willingness to be involved in the testing.

Copyright, January 15, 1998, Good Fruit Grower,105 South 18th Street, Suite 217, Yakima, Washington 98901
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