Reaction catalyzed by inulin fructotransferase (DFA-I-forming) (4.2.2.17)

		=			+
	beta-D-fructofuranosyl-(2->1)-beta-D-fructofuranosyl-(2->1)-beta-D-fructofuranosyl-(2->1)-beta-D-fructofuranosyl-(2->1)-alpha-D-glucopyranoside	=		di-D-fructofuranose-1,2':2,1'-dianhydride	+		1-kestose