USE OF HELIANTHUS-TUBEROSUS FOR FRUCTOSE PRODUCTION AND CARBOHYDRATE CONTENTS IN RELATION WITH TUBERS SIZE

Carbohydrate contents of Jerusalem artichoke (Helianthus tuberosus L.) changed with the size of tubers, the highest content being found in s mall tubers. This would be an important factor in the production of a high quality fructose syrup. In the Jerusalem artichoke, besides sucro se, glucose and fructose, glucofructosans have been detected at all st ages of development of the tubers. The carbohydrate contents averages 55 to 75% of the dry matter, that is to say a production amounting to 6,5 T/ha (5,9-7,2). The tubers lose a fraction of their carbohydrates in winter: 32,3% for the Kharkov and 45,1% for the Violet de Rennes cu ltivar.