2003 Annual Report for FW02-008
Increasing Marketable Production of Exotic Tropical Fruit with Protective Covering
Summary
OBJECTIVES
This study is investigating the effects of using protective bags on tropical fruit as a means of increasing production and quality and developing new markets for Hawaii. Results are being measured by the economic impact through market development and the horticultural value of using protective fruit wrapping as an alternative to chemical treatment.
SUMMARY
Asian farmers have been covering their fruit for hundreds of years to protect its appearance and increase the time the fruit is on the tree to make it sweeter. In some locations, the bags protect against pests. More than 3,000 types of bags are manufactured in Japan alone with variations in size, color, light permeability, wax coverings and chemical impregnation, for example with 0.05% diazinon. The bags typically have a small wire at the top to ease wrapping and slits in the bottom to drain rainwater.
The bags used in this Western SARE-funded project were made in Nigata, Japan, and typically used to cover apples, Asian pear, loquat, peaches, grapes and mango to control ripening time, achieve desired color and prevent pests. Members of the Hawaii Tropical Fruit Growers, West Hawaii Chapter; Kona Pacific Farmers Cooperative; and Kona Young Farmers participated in several tests to determine the best time for bagging. Fruit bagged included loquat, white sapote, mango, lychee, figs and rambutan. Some collaborators also tested abiu, pineapple, strawberry guava, tomato, zucchini and eggplant.
In all cases, the bags effectively controlled pests. They also increased fruit value by improving coloration and lengthening tree-hanging time, making fruit available off season. A surprise result was reduced labor, with the bags’ success drastically reducing inspection and culling time. Also, the bags protected fruit typically not found in stores because of bird or insect damage, expanding the market potential for loquat, white sapote and abiu. Marketable lychee also increased as did its price per pound. Bagging mango, figs and guava was also beneficial, but more testing is needed to determine the best type of bags to use.
RESULTS
A number of collaborators tested various fruits, and results are reported by type of fruit bagged:
Loquat. Loquat, popular in many countries, has yet to find favor in Hawaii or U.S. markets, mainly because birds and other pests destroy the fruit before it ripens. The fruit was bagged after thinning. Results show far less damage on bagged fruit than on fruit not bagged. In the absence of a local market for loquat, the project team sent samples to several hotels, grocers and the cooperative farmers market. One chef called to say he would buy all loquats that could be supplied. Based on these results, the team sought and received a permit to import new varieties from Japan, expected to be in full production in four years.
Lychee. This fruit underwent the most extensive testing, with fruit bagged on trees at five locations.
Translucent white bags with 50% light transmission promoted more even ripening and allowed the fruit to remain on the trees three weeks longer than usual, allowing it to ripen more fully and sell fruit beyond the normal season. An unexpected benefit was found in labor. Part-time labor for bagging cost $10-12 compared with $12-15 during harvest, and the average time to harvest and prepare an order of lychee was cut in half because of reduced culling.
“We believe that the increase in labor cost and the cost of the bag is more than offset by the greater number of fruit that is marketable and by the time saved during the culling process,” says Love. He said bagged lychee fetches $3.50 a pound compared with $2.75 a pound for unbagged fruit. Translated into 1,000 lychee, the added profit is $75, or $3,750 per acre using the bags.
Figs. The bagged figs in this project, five trees at three locations, were thought to be the first in Hawaii. Previously, to protect the fruit against birds and fruit flies growers strung CDs, aluminum foil or Christmas tinsel and left a half dozen fruit fly traps around the tree. With the bags, however, the percentage of undamaged figs increased, and figs inside bags with less light transmission remained green but ripened, becoming soft and sweet. Love says fresh bagged figs represent a potential market. Currently, some fresh figs are sold to the local grocery and farmers market, with some processed into jam for two local shops and a shop in Japan. However, wholesalers, hotels and West Coast distributors have been asking for quantities.
Abiu. The popularity of this fruit is growing in local and mainland markets, warranting expanded production. Love says five prolific trees are unable to supply the demand of just one customer. Abui’s attractive yellow color appeals to consumers as well as to birds, fruit flies and many other pests. The fruit was bagged at two locations with a light brown wax-coated bag with 61% light transmission. The bagged fruit had little insect damage or visible imperfections while all of the fruit not bagged had damage, mainly bird and fruit fly stings, that would prevent it from being sold.
“In previous years,” says Love, “we have been able to get few fruit to market that had not been bagged. Our conclusion is that bagging abiu is the only way to make it marketable in West Hawaii.”
White Sapote. This fruit thrives at higher elevations, but sensitive skins often prevent marketing. Also, white sapote fruit often aborts or is knocked from the trees by strong winds. Some of the 200 fruit bagged at four locations fell off the branch and into the bag, but the 184 fruit harvested had more even color and less skin damage, with just less than half being of marketable quality. Loves says white sapote will ripen after harvest, and the use of bags, along with evidence from taste tests, mean this fruit has a potential market.
Mango. Mangoes are successfully bagged in Japan and elsewhere in Asia, but their pest problems may not be as severe as in Hawaii. Bags with open bottoms were free of pests, but those with closed bottoms suffered pest problems, including roaches and borers. While the bagged mangoes tended to provide a greater amount of marketable fruit than those not bagged, more research is needed to determine the types of bags to use for different varieties and the best time to bag them.
Other tests. Tests on other fruit clearly show the need for more testing. However, preliminary tests on tomato, white pineapple, cucumber and guava are encouraging.
IMPACT ON AGRICULTURE
Love says that while many farmers are slow to adopt change, evidence from this fruit-wrapping project provides obvious appeal, especially economic benefits. The time saved in the culling process outweighs the time taken to bag the fruit. The difference in quality is both visible and marketable.
“We believe that as farmers adopt the use of the protective bags, the value of the crop will increase both from quality and quantity,” says Love. “Use of the bags enables farmers to increase production while staying chemical- and pesticide-free in what they grow and bring to the market, thus promoting good stewardship of the land.”
Love adds that sales of the bags should help the Kona Pacific Farmers Cooperative increase equity for members. And the increased availability of unusual fruit will help with consumer awareness in developing extended markets for farmers choosing to expand their crop diversity.
PRODUCER ADOPTION
In response to the weekly display at the Kona Pacific Cooperative Farmers Market and a presentation at the International Hawaii Tropical Fruit Growers conference in October 2002, several growers have inquired about buying the bags and requested shipments from Japan. New farmers are given samples, some of which are used on home-grown tomatoes and cucumber, both susceptible to fruit fly. Many growers are reluctant to buy the bags until they are certain of results, and the Western SARE grant has enabled the project team to distribute 100 bags to farmers for their own testing.
RECOMMENDATIONS
With more than 3,000 types of bags being made, further testing is needed to find the optimum bag for each type of fruit. Publicity in publications about the bags could encourage their use, as would testimonials from chefs or fruit buyers about the quality they engender.
OUTREACH
Results of the project were presented during the International Hawaii Tropical Fruit conference in October 2002, providing attendees from the islands as well as Southeast Asia and Florida with information and bag samples. The presentation is also on the Internet, as are reports and photos from the project, www.mycoffee.net/fruitindex.html. The project coordinator has also been asked to present information about bag use during a conference in Indonesia in August 2003. A display appears at the weekly farmers market, including bags and bagged fruit.