SBIR-STTR Award

Chinese chestnuts have the potential for greatly expanded commercial production in the U.S.A. Locally produced chestnuts could replace imported chestnuts in the marketplace as well as exploit new markets. One barrier to commercial production is lack of harvest technology. We propose determining efficacy and costs of 2 harvesting methods: 1) allowing ripe chestnuts to naturally fall onto tarps placed under trees; and 2) using a mechanical trunk shaker to shake chestnuts onto tarps. We will also determine: I) changes that occur in chestnuts immediately before ripening; 2) changes that occur in chestnuts after ripening; 3) length and distribution of natural nut drop; and 4) effect of weather parameters on ripening and nut drop.

Commercial chestnut production in the U.S. could be greatly expanded, displacing our 12 million per year importation, as well as exploiting new markets. Chestnuts are a highvalue, low-input crop, well adapted to many U.S. growing conditions. Prerequisites for competing in the U.S. and world market are mechanization of harvesting and handling operations while maintaining high quality of this perishable crop. In Phase I, we found that successful shake-harvesting is limited to "easy shaking" clones and no more that a 3-4 day harvest window. Also, we found that sugar content of chestnuts ranged from 5-25%, depending on storage conditions. For Phase II, we will explore mechanical pick-up harvesting and develop machinery to thrash (remove burs) and peel (remove shells) chestnuts. Also, we will further explore the effects of storage on sugar formation and study postharvest molding, including mycotoxin risks. A major goal is to develop knowledge and technology for production of high quality peeled chestnuts, which will greatly increase marketing and processing options. Also, we will develop grading standards for chestnuts which may form the basis for USDA grades (none presently exist).Applications:With proper storage and handling technology, we will be able to pursue our Phase III goal of developing and marketing high quality peeled chestnut products. Such products will provide a market for small-sized chestnuts which are already locally produced, but arc not easily marketed. The results of this research will be applicable in all regions of the country, including the Pacific Northwest and fruit-growing region of Michigan, both of which are beginning to expand chestnut production.