Fruit coatings made from reformulated shellac and sucrose ester have been shown to help maintain fruit quality after harvest by promoting the growth of beneficial natural yeast and bacteria populations on fruits. In trials at ARS Subtropical Horticulture Research Station in Miami, Florida, in cooperation with Mantrose Haeuser Co Inc. of Westport, Connecticut, application of shellac formulations to grapefruits (cv. Marsh) facilitated higher epiphytic populations on the fruit surface and delayed fruit decay in storage. The bacterial and yeast populations help maintain fruit quality by competing more efficiently than pathogens for nutrients, such as sugars and proteins, at a critical early stage in the pathogen's development. Preliminary test results also indicated that the coatings prevented off-flavours by allowing for a better exchange of oxygen and carbon dioxide than commercial chemicals permit.
For further information contact:
Raymond G. McGuire, ARS Subtropical Horticulture Research Station, Miami, Florida, USA.
Tel: (305) 254 3641.Fax (305) 238 9330.Email:

Improved Potato Storage in Madagascar

The Vakinankaratra region of Madagascar produces about 60% of the national potato harvest. Three crops are grown per year: the main crop, rainfed from October to February: the second rainfed crop of limited acreage from January to May; and the irrigated crop from June to September. Prices are lowest in January-February when the main crop is harvested. With adequate storage facilities, farmers would not be obliged to sell their harvest immediately but could store it until market prices improve. Experiments with storage systems have shown consistently good results.
Under the ASARACA (Association for Strengthening Agricultural Research in Eastern and Central Africa) Technology Transfer Project, the Centre de dévelopment Rural et de Recherche Appliquée (FFIAMANOR), with the support of scientists from Centro Internacional de la Papa (CIP), is undertaking a project with the aim of storing consumption potatoes for longer periods to fetch better prices. The beneficiaries are the members of the farmers associations in Vakinankaratra region where potatoes are the principal crop.
Selected farmer groups were sensitized on improved storage systems and informed about their own contribution towards the construction of the stores. The farmers were trained and they contributed local materials, about a tenth of the total material cost, plus their labour towards the construction of the storage buildings. Five naturally ventilated potato stores were constructed. Strong partnerships were established between the project and the farmer associations. The latter were involved in the initiation of the project and the planning stages. On average, 72% of the total cost was met by the project itself while the beneficiaries contributed 28%.
Many other regions have expressed demand for improved storage facilities. The availability of these facilities has greatly reduced demand on transportation. Only small recurrent costs for the maintenance of the storage chambers are needed, which the farmers association themselves can meet.
This storage system could be expanded to other crops.

For further information contact:
Director, FIFAMANOR, BP 198, Antsirabe 110, Madagascar. Tel: 261 2 4448954. Fax: 261 2 4449964.

From: AgriForum

Fresh-cut Mangoes for the Market

Mangoes could be an attractive addition to the growing market for fresh-cut produce, but browning and drying have prevented such marketing. Researchers at the USDA-ARS Horticultural Crops Quality Laboratory found that fresh-cut mangoes could be preserved by treating the slices with a combination of hexylresorcinol, isoascorbic acid and potassium sorbate (all food-safe compounds derived from natural products) and storing the slices in plastic containers to prevent drying.
Treating whole fruits with methyl jasmonate (an inexpensive product derived from plant essential oils) prevented the development of chilling injury during cold storage and hence markedly increased fruit quality after storage. The treatment worked on fruits at various stages of maturity and had no effect on ripening or softening processes or water loss.
For further information contact: Chien Y. Wang, USDA-ARS Horticultural Crops Laboratory, Beltsville, Maryland, USA. Tel: (301) 5046128 Email:

FAIR Project Assesses Mealiness in Apples

Participants in the European FAIR project (CT 95-302) developed non-destructive techniques for the measurement of mealiness in apples and studied the factors affecting mealiness and its effects on consumers.
Mealiness is described as the tendency of fruits to disintegrate, combined with a sensation of lack of juiciness and dryness in the mouth, as well as the absence of flavour. In December 1996, researchers from the Universidad Politécnica de Madrid (UPM), from Katholieke Universiteit Leuven (KU) and from the Institute of Food Research in the UK carried out trials to determine correlations between the assessment of mealiness by a panel and objective measurements (mechanical resonance and confined compression). The results allowed the development of techniques for determining crispness (the absence of which is correlated with mealiness), hardness and juiciness (also correlated with mealiness) without the need for taste panels.
A scale for determining mealiness was used by UPM, in collaboration with IRTA (Spain), for studying factors which could affect the incidence of mealiness in apples. The studies concluded that (i) large-size Top Red apples harvested late showed a high incidence of mealiness, and (ii) no effect of harvesting date on mealiness was observed in Golden Delicious apples, although fruit size and mealiness were linked. Similar studies carried out at KU and VCBT (Flemish Centre for Storage of Agricultural Products), combining harvesting dates, fruit size and the concentration of oxygen in the storage atmosphere, showed that, after 6 months' storage, apples stored in air showed a higher incidence of mealiness than those held in a low-oxygen atmosphere.
Surveys of producers, distributors and consumers indicated that all groups perceived mealiness as detrimental to fruit quality, although there was a segment of older consumers who preferred mealy fruits because they were softer and overmature. The quality characteristic rated highest was taste, followed by appearance and firmness.

Hawaiian Bananas Free from Fruit Flies

Research carried out by John W. Armstrong and colleagues at the US Pacific Basin Agricultural Research Center in Hilo, Hawaii has allowed the USDA's Animal and Plant Health Inspection Service to approve new, workable regulations for shipping bananas grown in Hawaii to the US mainland. Since the ban on ethylene dibromide was imposed in 1984, bananas have not been shipped to the mainland due to the threat of fruit fly infestation. Mediterranean (Ceratitis capitata) and oriental fruit flies (Bactrocera dorsalis) are established in Hawaii and pose a threat to mainland agriculture where they can attack more than 200 fruits and vegetables.
Using laboratory-reared fruit flies, thousands of bananas from nearly 2 dozen plantations throughout the State were tested. The research, carried out in the laboratory and outdoors, demonstrated that bananas won't harbour these pests if shipped full-size, green-skinned and without cuts or punctures. Shipments to other markets such as Japan are now on the horizon.
For further information contact:
John Armstrong, USDA-ARS,  US Pacific Basin Agricultural Research Center, Stainback Highway,

PO Box 4459, Hilo, HI 96720, USA.Tel: (808) 959 4336, Fax: (808) 959 4323