this invention relates to improve water dispersibility of fiber containing dietary products . these products are typically used as bulk forming laxative . these fiber containing products are derived from natural sources of polysaccharides such as husk of grains especially psyllium , celluloses , methylcelluloses , gum guar , vegetables fiber , fruits fiber , and amylopectin - rich starch . they can also be chemically modified fiber materials of polysaccharides such as etherification , esterification , hydroxyethoxylation , or hydroxypropoxylation of the above mentioned natural resources of polysaccharides . examples are hydroxyethyl cellulose , hydroxypropyl cellulose , hydroxypropyl amylopectin and the like . polysaccharides are carbohydrates with general repeat units of ( c 6 h 12 o 6 ). polysaccharides can also be defined as polyhydroxy aldehydes and ketones or substances that hydrolyze to yield such compounds . these fiber containing products usually do not disperse adequately in water at room temperature . surface active agents are called surfactants . they are molecules containing both hydrophobic ( water hating ) and hydrophilic ( water loving ) characters . a surfactant structure typically contains at least a hydrophobic hydrocarbon chain such as an alkyl group of carbon number 3 to 30 , and at least a hydrophilic group such as a sulfonic acid or a carboxylic acid , or an ethoxylated group . when the hydrophilic group is anionic charged , the surfactant is normally called an anionic surfactant . if the hydrophilic group is an ethoxylated group , the surfactant is usually called a non - ionic surfactant . the hlb number was first developed by griffin in 1949 to describe the hydrophobic and hydrophilic characters of surfactants . the hlb number has been proved very successful with alkoxylated non - ionic surfactants . griffin proposed to calculate the hlb number from its chemical structure , i . e . hlb =% of the hydrophilic group ( molar ) divided by 5 . thus the maximum hlb number was 20 and represented a completely water soluble surfactant . a hlb of zero represented a completely water insoluble material . an approximate hlb number can be obtained by adding a small quantity of a surfactant ( say 0 . 1 - 10 %) to water and shaking at room temperature . they are typically characterized as follows : ______________________________________hlb number appearance on adding surfactant to water______________________________________1 - 4 insoluble4 - 7 poor dispersion unstable7 - 9 stable opaque dispersion10 - 13 hazy solution13 - 20 clear solution______________________________________ in general , materials that are not readily wet by water can be coated with surfactants of high hlb number ( greater than 10 ) to make them more water wettable and dispersable . in contrary , this invention teaches unexpected results , wherein the dietary fibrous products that are not readily dispersible in water can have improved water wettability and dispersibility by partially or fully coating with surfactants of low hlb number ( between 4 and 9 , preferably between 4 and 7 ). in addition , surfactants of hlb in this range generally have bacteriostatic effects . it can further help increase the shelf life of the coated products . the classes of preferred surfactants are generally the ones regulated by u . s . fda with gras or gmp status . gras means &# 34 ; generally recognized as safe &# 34 ;: their safety is generally based on extensive toxicological test data or based on use experience for an extended period of time , but their use may be limited . gmp means &# 34 ; good manufacturing practicel &# 34 ;: their use not limited as to quantity or application . the most preferred ones comprise lecithin , modified lecithin , mono - and diglycerides , sucrose esters , lactic acid esters of mono - and diglycerides , polyglycerol esters of fatty acid , propylene glycol esters of fatty acid , diacetyl tartaric acid esters of mono - and diglycerides , acetic acid esters of mono - and diglycerides , citric acid esters of mono - and diglycerides , salts of fatty acid . another class of surfactants that is also preferred to be used in this invention but with more u . s . fda regulation comprise ethoxylated monoglyceride , sorbitan monoalkylester , polysorbate , succinylated monoglycerides , sodium or calcium stearoyl lactylate . their acceptable daily intake is normally regulated to be less than 25 mg / kg of body weight . the coating weight of the said surfactants on the substrates are usually between 0 . 1 % and 10 %, preferably between 0 . 4 % and 5 %. depending upon the cost of the said surfactants and the coating substrates , one may choose to use more or less surfactants to optimize the cost and performance . the following examples are used only to demonstrate the concept . 50 grams of psyllium powder ( from its husk ), 20 to 200 mesh , is placed in a suitable mixer and blended with 0 . 5 gram of a mono - and diglycerides surfactant mixture containing glyceryl caprylate and glyceryl caprate ( cas number 26402 - 22 - 2 and 26402 - 26 - 6 ) with hlb number between 5 . 5 and 6 . 0 . they were dry blended for 30 minutes at 60 degree celsius . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 5 grams of an isopropyl alcohol solution containing 0 . 25 gram of the same surfactant mixture as described in example 1 . they were blended at room temperature and then dried for 30 minutes at 60 degree celsius to remove all of the isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 5 grams of an isopropyl alcohol solution containing 0 . 25 gram of a surfactant : glyceryl caprylate ( cas number 26402 - 22 - 2 ) with hlb number between 6 . 0 and 6 . 5 . they were blended at room temperature and then dried for 30 minutes at 60 degree celsius to remove all of the isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 3 . 5 grams of an isopropyl alcohol solution containing 0 . 5 gram of a surfactant polysorbate 60 ( cas number 9005 - 67 - 8 ) with hlb number about 15 . they were blended at room temperature and dried for 30 minutes at 60 degree celsius to remove all of isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 2 . 5 grams of an isopropyl alcohol solution containing 0 . 5 gram of a surfactant sorbitan monooleate ( cas number 1338 - 43 - 8 ) with hlb number about 4 . 3 . they were blended at room temperature and dried for 30 minutes at 60 degree celsius to remove all of isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 2 . 5 grams of an isopropyl alcohol solution containing 0 . 5 gram of a surfactant polyoxyethylene ( 5 ) sorbitan monooleate ( a commercial name is tween 81 ) with hlb number about 10 . they were blended at room temperature and dried for 30 minutes at 60 degree celsius to remove all of isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 2 . 5 grams of an isopropyl alcohol solution containing 0 . 5 gram of a surfactant sorbitan monolaurate ( cas number 1338 - 39 - 2 ) with hlb number about 8 . 6 . they were blended at room temperature and dried for 30 minutes at 60 degree celsius to remove all of isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . 50 grams of psyllium powder , 20 to 200 mesh , is placed in a suitable mixer with 5 grams of an isopropyl alcohol solution containing 0 . 25 gram of a surfactant glyceryl oleate ( cas number 25496 - 72 - 4 ) with hlb number between 3 and 4 . they were blended at room temperature and dried for 30 minutes at 60 degree celsius to remove all of isopropyl alcohol in the sample . the sample was cool to room temperature and ready for water dispersibility test . a half teaspoon of a sample is placed evenly on top of 200 ml of drinking water inside a 250 ml beaker . start the timer to count the time that it takes to allow the sample to be wetted , dispersed automatically , and sink in water without any agitation . the results of the water dispersibility test was performed on all samples as well as the &# 34 ; control &# 34 ; sample that is the same psyllium powder without any surfactant coating . each sample was tested twice and the results reported are the average number . the result is listed below : ______________________________________ surfactantsample no . hlb no . time to be completely dispersed______________________________________ &# 34 ; control &# 34 ; uncoated 7 minutes , 48 secondsexample 8 3 - 4 7 minutes , 54 secondsexample 5 4 . 3 6 minutes , 03 secondsexample 1 5 . 5 - 6 . 0 0 minutes , 52 secondsexample 2 5 . 5 - 6 . 0 0 minutes , 28 secondsexample 3 6 . 0 - 6 . 5 3 minutes , 21 secondsexample 7 8 . 6 6 minutes , 56 secondsexample 6 10 9 minutes , 15 secondsexample 4 15 6 minutes , 20 seconds______________________________________ it is striking that surfactants with the hlb number between 4 . 3 and 8 . 6 offer significant wetting improvement over the uncoated &# 34 ; control &# 34 ; sample . the best hlb number seems to be between 5 . 5 and 6 . 5 . the results also show that the said surfactant can be applied in bulk to the coated substrates as in example 1 and achieve similar water wettability results as that with isopropanol solvent in example 2 .
this invention teaches unique water dispersible dietary compositions of natural or chemically modified fiber materials that have a surface coating with surface active agents with hlb number between 4 and 9 , preferably between 4 and 7 . the dietary product contain at least 10 % of fiber materials of essentially polysaccharides derived from sources selected from psyllium , celluloses , methylcelluloses , hydroxyethyl celluloses , hydroxypropyl celluloses , gum guar , vegetables , fruits , or other natural or chemically modified materials . surprisingly , these fiber containing materials coated with the said surfactants have significant improvement on water dispersibility . the type of surfactants disclosed usually present no harm to human body and can be easily applied to the said fibrous materials in bulk without any solvent .