The capacity of CGTase for using bCD (beta cyclodextrin) as glucosyl donor and transferring it to sucrose molecules was investigated. We showed that this enzyme was able to produce polyglucosyl-fructosides (G n F) by a coupling reaction between bCD and sucrose. Maltooligosaccharides were also synthesised but in lesser amounts. The degree of polymerisation (DP) of the different products was limited to a value of 8 and this allowed us to purify all of them by size exclusion chromatography. Mass spectrometry and NMR analysis of the unknown products revealed that they consisted of linear maltooligosaccharides of various DP bound to the glucose moiety of a sucrose molecule by a a(10/4) linkage.