Abstract: This invention concerns methods for synthesis and accumulation of fructose polymers in seed, tubers or leaves of transgenic plants by selective expression of a bacterial fructosyltransferase gene. Selective expression includes coordination of timing, tissue specific expression and especially subcellular location. Successful transformants utilize sucrose to synthesize and accumulate fructan in the vacuole of the cell, in established crops, without loss of co-products or concern for yield loss due to degradation during maturation, harvest or storage of the plant. Enhanced fructan production will benefit the fructose sweetener industry and add value to grain used for feed.