National Starch and Chemical Corporation

National Starch and Chemical Investment Holding Corporation

Morton W Rutenberg

Martin M Tessler

Robert L Billmers

Michael Timothy Philbin

Peter T Trzasko

Chung W Chiu

Joseph A Van Gompel

Chung-Wai Chiu

Daniel B Solarek

John J Tsai

James L Eden

James J Kasica

Wadym Jarowenko

Norman L Lacourse

Thomas R Molnar

John (Ji-Hsiung) Tsai

Timothy G Koubek

Leo Walsh

Cationic polysaccharide derivatives are prepared by reacting a polysaccharide with a polycationic reagent having one polysaccharide reactive group and at least two cationic groups. Suitable reagents include polycationic alkyl, aryl, alkaryl, cycloaliphatic, or heterocyclic amines, some of which are novel compositions. The polycationic polysaccharide derivatives prepared from these reagents are useful in the manufacture of paper.

Cationic polysaccharides and reagents for their preparation

A steam-stripping process suitable for the removal of impurities from polysaccharides, including soluble starch hydrolysates, is disclosed herein. This process may be used in combination with other purification processes, such as ultrafiltration, ion exchange, treatment with activated carbon, as well as bleaching process. Soluble starch hydrolysates may also be purified by a combination of ultrafiltration or activated carbon treatment and bleaching. In these processes, the polysaccharide or the soluble starch hydrolysate produced is bland in flavor, free of off-odor, optionally, lighter or white in color and suitable for use in systems requiring these characteristics. Other purification process combinations which are disclosed for removal of undesirable flavors, odors and/or colors from polysaccharides include: 1) ultrafiltration and carbon treatment; 2) ultrafiltration and steam-stripping; 3) steam-stripping and carbon treatment; 4) ion exchange treatment and ultrafiltration; 5) ion exchange treatment and steam-stripping; and 6) ion exchange treatment and carbon treatment. A bleaching process may precede any of these processes. If ozone or a peroxide is employed, the bleaching step may follow any of these processes. Any of the processes may be combined with other processes disclosed herein to provide additional purification measures. The processes are particularly useful for purification of low molecular weight soluble polysaccharide hydrolysates, such as dextrins. These purified polysaccharides are used in improved foods, adhesives, pharmaceuticals and like products.

Purification of polysaccharides

Guar gum is prepared by hydrating guar splits with sufficient water to provide a total moisture content of 25-80%, extruding the hydrated splits, and grinding them, while wet, preferably to a finely divided state. For most uses the ground gum is then dried, preferably in a flash dryer. Typically the hydration is carried out at 5.degree.-95.degree. C. for at least 1/4 hour; the preferred conditions are 20.degree.-80.degree. C. for 0.5 to 2 hours. The extrusion is conveniently carried out in an extruder provided with a rotatable screw for transporting and working the hydrated splits. Typically grinding is carried out in a hammermill.

Preparation of guar gum

A cold-water dispersible, modified starch characterized by forming a gel having a Bloom strength of at least 50 grams is prepared by reacting a tapioca starch with a crosslinking agent to within defined Brabender viscosity limits; converting the crosslinked starch in a sufficient amount to provide the modified starch with gelling properties; and drum-drying the crosslinked and converted starch to obtain the modified starch product. The gelling instant starch thus prepared is particularly useful in food systems of the type which gel upon standing, such as pie filling, jellies, and puddings.

Cold-water dispersible, gelling starch

A cold-water dispersible, modified starch characterized by forming a gel having a Bloom strength of at least 60 grams is prepared by reacting a potato starch with a crosslinking agent to within defined Brabender viscosity limits sufficient to provide the modified starch with gelling properties and drum-drying the crosslinked starch to obtain the modified starch product. The starch may be optionally converted to a fluidity starch either before or after the crosslinking step and prior to drum drying. The gelling instant starch thus prepared is particularly useful in food systems of the type which gel upon standing, such as pie fillings, jellies, and puddings.

Cold-water dispersible, gelling potato starch

A cold-water dispersible, modified starch characterized by forming a gel having a Bloom strength of at least 45 grams is prepared by converting a tapioca starch to a water fluidity of about 10 to 63, preferably 20 to 40; reacting the starch with a crosslinking agent to within defined Brabender viscosity limits sufficient to provide the modified starch with gelling properties; and drum-drying the converted, crosslinked starch to obtain the modified starch product. The gelling instant starch thus prepared is particularly useful in food systems of the type which gel upon standing, such as pie fillings, jellies, and puddings.

Cold-water dispersible, gelling starches

Highly substituted granular starches are prepared by reacting the starch in an aqueous system with a reagent capable of producing an acetal cross-linkage; reacting the resultant acetal cross-linked starch with a mono-functional esterifying or etherifying reagent under aqueous alkaline conditions and removing the acetal cross-linkages by treating under acid conditions. The highly substituted starches are particularly useful in operations, such as papermaking, wherein the cross-linkages can be removed and the starch readily dispersed during a relatively low pH starch cooking process.

Growing community of inventors

North Plainfield, NJ, United States of America

Morton W Rutenberg