Process for gelatinising starch using a biodegradable polymer material bearing aldehyde groups

Abstract

The invention provides a process wherein starch and/or a starch derivative can be gelatinised more efficiently by means a thermo mechanical treatment, when a carbohydrate polymer is used comprising aldehyde containing monomer units which comprise one or more aldehyde groups that are derived from one or more a primary alcohol groups. With this process a granulate or other semi-finished product can be obtained that can be shaped to produce an article that has excellent dimensional stability in water. The invention further provides a granulate, a shaped starch product, a food product or a blown starch film comprising such a carbohydrate polymer.

1 .- 16 . (canceled) 
     
     
         17 . A powder of thermoplastic starch that comprises a carbohydrate polymer in an amount of at least 10 weight %, based on total thermoplastic starch, with the proviso that the percentage of the starch is at least 30 wt. %, which carbohydrate polymer comprises aldehyde containing monomer units, whereby at least 1% of the aldehyde containing units have one aldehyde group per monomer unit which one aldehyde group is derived from a primary alcohol group at the C-6 position. 
     
     
         18 . A granulate of thermoplastic starch that comprises a carbohydrate polymer in an amount in the range of from 3 to 75 weight %, based on total thermoplastic starch, a polyol or urea as plasticizer and water, which carbohydrate polymer comprises aldehyde containing monomer units, whereby at least 1% of the aldehyde containing units have one aldehyde group per monomer unit which one aldehyde group is derived from a primary alcohol group at the C-6 position. 
     
     
         19 . A shaped starch product that comprises thermoplastic starch and a carbohydrate polymer, wherein the carbohydrate polymer is present in an amount in the range of from 3 to 75 weight %, based on total thermoplastic starch, a polyol or urea as plasticizer and water, which carbohydrate polymer comprises aldehyde containing monomer units, whereby at least 1% of the aldehyde containing units have one aldehyde group per monomer unit which one aldehyde group is derived from a primary alcohol group at the C-6 position. 
     
     
         20 . A blown starch film that comprises a thermoplastic starch and a carbohydrate polymer, wherein the carbohydrate polymer is present in an amount in the range of from 3 to 75 weight %, based on total thermoplastic starch, a polyol or urea as plasticizer and water, which carbohydrate polymer comprises aldehyde containing monomer units, whereby at least 1% of the aldehyde containing units have one aldehyde group per monomer unit which one aldehyde group is derived from a primary alcohol group at the C-6 position. 
     
     
         21 . A food product that comprises a food component and a carbohydrate polymer, which carbohydrate polymer comprises aldehyde containing monomer units, whereby at least 1% of the aldehyde containing units have one aldehyde group per monomer unit which one aldehyde group is derived from a primary alcohol group at the C-6 position. 
     
     
         22 . A powder according to  claim 21 , wherein said carbohydrate comprises a non-cleaved vicinal diol system. 
     
     
         23 . A granulate according to  claim 18 , wherein said carbohydrate comprises a non-cleaved vicinal diol system. 
     
     
         24 . A shaped starch product according to  claim 19 , wherein said carbohydrate comprises a non-cleaved vicinal diol system. 
     
     
         25 . A blown starch film according to  claim 20 , wherein said carbohydrate comprises a non-cleaved vicinal diol system. 
     
     
         26 . A food product according to  claim 21 , wherein said carbohydrate comprises a non-cleaved vicinal diol system. 
     
     
         27 . A powder according to  claim 17 , comprising water in a relative amount of 10-60 g per 100 g starch. 
     
     
         28 . A granulate according to  claim 18 , comprising water in a relative amount of 10-80 g per 100 g starch. 
     
     
         29 . A shaped starch product according to  claim 19 , comprising water in a relative amount of 10-80 g per 100 g starch. 
     
     
         30 . A blown starch film according to  claim 20 , comprising water in a relative amount of 10-80 g per 100 g starch. 
     
     
         31 . A food product according to  claim 21 , comprising water in a relative amount of 10-80 g per 100 g starch. 
     
     
         32 . A powder according to  claim 17 , comprising 8-45 wt % plasticizer other than water based or total weight biopolymer. 
     
     
         33 . A granulate according to  claim 18 , comprising 8-45 wt % plasticizer other than water based or total weight biopolymer. 
     
     
         34 . A shaped starch product according to  claim 19 , comprising 8-45 wt % plasticizer other than water based or total weight biopolymer. 
     
     
         35 . A blown starch film according to  claim 20 , comprising 8-45 wt % plasticizer other than water based or total weight biopolymer. 
     
     
         36 . A food product according to  claim 21  comprising 8-45 wt % plasticizer other than water based or total weight biopolymer. 
     
     
         37 . A powder according to  claim 17 , comprising a polyol or urea as plasticizer and water 
     
     
         38 . A granulate of thermoplastic starch according to  claim 18  comprising in addition a polyester. 
     
     
         39 . A shaped starch product according to  claim 19 , comprising in addition a polyester. 
     
     
         40 . A blown starch film according to  claim 20 , comprising in addition a polyester.