Slowly digesting starch and fermentable fiber

Abstract

Compositions which provide slowly digestible starch and a source of fermentable dietary fiber. Microparticles in which starch is entrapped in a crosslinked matrix to provide dietary benefit. Such microparticles are used to deliver glucose to targeted regions in the small intestine for beneficial physiological effects, and fermentable dietary fiber to the colon to improve colon health and to treat diseases of the colon. Microparticles can be employed to selectively deliver fermentable dietary fiber to targeted portions of the colon.

We claim: 
     
         1 . Microparticles comprising a crosslinked polymer matrix with entrapped starch made by a method for preparation of a starch composition to slow starch digestion comprising
 mixing an ionically crosslinkable polymer, a starch, and water to form a mixture, and   forming crosslinked microparticles from the mixture, where each microparticle comprises starch entrapped within the crosslinked polymer matrix to slow digestion of the starch,   wherein the ionically crosslinkable polymer is a polysaccharide gum,   wherein the ionically crosslinkable polymer is alginate, pectin, gellan, or mixtures thereof,   wherein the weight ratio of the ionically crosslinkable polymer to starch is about 0.01 to about 0.5 in the mixture,   wherein the polymer is ionically crosslinkable with divalent cations and the forming step comprises introducing drops or droplets of the mixture into a calcium chloride solution,   wherein the mixture further comprises non-starch based fiber, and   wherein the non-starch based fiber is a prebiotic.   
     
     
         2 . The composition of  claim 1  wherein starch represents 50% or more of the dry weight of the composition. 
     
     
         3 . A food product containing a composition of  claim 1  or  2 . 
     
     
         4 . A therapeutic or prophylactic composition comprising an effective amount of a composition of  claim 1  or  2 . 
     
     
         5 . A method for controlling blood glucose levels in an individual who will benefit from such control which comprises periodic oral administration of a composition of  claim 1  or  2 . 
     
     
         6 . A method for selective delivery of fermentable fiber to the colon which comprises administration of starch-containing microparticles of  claim 1  or  2 . 
     
     
         7 . A slowly fermentable fiber prepared by a method for preparing a fermentable fiber which comprises the steps of
 mixing an ionically crosslinkable polymer, a starch, and water to form a mixture, and   forming crosslinked microspheres from the mixture, where each microsphere comprises starch entrapped within the crosslinked polymer matrix a portion of which entrapped starch remains undigested on ingestion and passage through the stomach and small intestine,   wherein the ionically crosslinkable polymer is alginate, pectin, gellan, or mixtures thereof,   wherein the weight ratio of the ionically crosslinkable polymer to starch is about 0.01 to about 0.5 in the mixture,   wherein the mixture further comprises non-starch based fiber   wherein the non-starch based fiber is a prebiotic, and   wherein the starch containing crosslinked microspheres are measured to have 10% or more resistant starch.   
     
     
         8 . A method for maintaining colon health which comprises periodic ingestion of a slowly fermentable fiber of  claim 7  or a food product containing the slowly fermentable fiber. 
     
     
         9 . A method for treating a disease of the colon which comprises periodic oral administration of a slowly fermentable fiber of  claim 7 . 
     
     
         10 . A low GI food product which also exhibits slow glucose release which comprises microparticles having a crosslinked polymer matrix with entrapped starch therein. 
     
     
         11 . Microparticles consisting essentially of a crosslinked polymer matrix with starch entrapped in the matrix. 
     
     
         12 . The microparticles of  claim 11  wherein the polymer is alginate crosslinked with calcium ions.