Patent Application
20220167649
The present invention relates to a process for preparing a readily dispersible hydrocolloid composition and to the use of the composition prepared by the process in the management of dysphagia.
Dysphagia is a condition resulting from a disorder in the mechanics of swallowing, which can lead to impairment in the safety, efficiency or quality of eating and drinking. Dysphagia can be caused by many disorders including neurological disorders such as stroke, traumatic brain injury, Huntington's disease, multiple sclerosis, Parkinson's disease and cerebral palsy. Many of these conditions are associated with the elderly and, with the continuing demographic shift, dysphagia is a growing problem.
The use of food and liquids with modified texture or rheology is an established clinical practice to address dysphagia. The practice has been based on the assumption that modifying the rheology of normal foods and liquids makes them easier and safer to swallow. It is commonly accepted that thin liquids such as water, tea, coffee, squash and juice flow quickly in the mouth during the swallowing process and can cause aspiration. Aspiration is the entry of foods or liquids into the airway and often manifests as coughing or choking during swallowing. This can lead to a reluctance to eat or drink with the subsequent risk of malnutrition or dehydration. In the longer term, if not controlled, aspiration can lead to complications with the respiratory system such as chronic obstructive pulmonary disease or aspiration pneumonia. The general practice is to increase the viscosity of the liquid to decrease the risk.
A class of thickeners that are used in products for managing dysphagia are hydrocolloids. Hydrocolloids are frequently provided by manufacturers in the form of a dry granulate and can be difficult to disperse in water and other liquids as they tend to lump during hydration. The physico-chemical basis for lumping of hydrocolloids during hydration and dispersion is surface-to-surface cross-linking and/or gelling of polymer molecules at the surfaces of the hydrocolloid granules. At this stage, hydrated polymer molecules at the granule surface are fully or partially ejected from the surface. This gives a high concentration of hydrated polymers at or in the vicinity of the granule surfaces. When granules are added to a liquid/water, thousands of particles are present in a small volume, each of which is surrounded by a liquid “cloud” with a high local polymer concentration that can potentially cross-link and form gels between granules which will then get sticky and lump together. The formation of lumps slows the overall dissolution process as a result of limited access of the liquid to the interior of the lump.
There is a need to develop a hydrocolloid-based thickener composition for the management of dysphagia with improved dispersibility in water or aqueous liquids to allow for ready hydration and solubilisation.
In the course of developing a hydrocolloid-based product with improved rheological properties for the management of dysphagia, the present inventors have developed a process to combine xanthan gum and carboxymethyl cellulose in a composition which does not lump when dispersed in water and which does not require intense agitation to disperse, but can be stirred with a spoon by the end user (such as a patient with dysphagia or a carer).
Accordingly, the present invention relates to a process for preparing a readily dispersible hydrocolloid composition, the process comprising
In another aspect, the invention relates to the readily dispersible hydrocolloid composition prepared by the process.
In a further aspect, the invention relates to the readily dispersible hydrocolloid composition for use in the management of dysphagia.
In the present context, the term “hydrocolloid” is intended to indicate a hydrophilic substance capable of forming a colloidal dispersion of finely divided particles in a liquid, in particular water. The colloidal particles bind water by hydrogen bonds. Examples of hydrocolloids are biopolymers such as alginate, carrageenan, pectin, cellulose derivatives such as carboxymethyl cellulose, xanthan gum, succinoglycans, gellan, guar gum, locust bean gum and starches. Preferred hydrocolloids are cellulose derivatives or xanthan gum. In the present context, “hydrocolloid” is used collectively to indicate xanthan gum and carboxymethyl cellulose. A “hydrocolloid composition” is a composition comprising particles of a hydrocolloid.
The term “readily dispersible” or “ready dispersibility” is intended to indicate the ability of agglomerated particles of the hydrocolloid composition to be immersed and flow as free single particles in water or an aqueous liquid without lumping or aggregating, shortly after which the particles will hydrate completely and eventually dissolve, cf.
The term “agglomerate” is intended to indicate particles composed of multiple granules of hydrocolloid(s) and one or more easily dispersible or water-soluble ingredients which act as a binder sticking the hydrocolloid granules together, cf.
The term “xanthan gum” is intended to indicate a polysaccharide produced by fermentation of the microorganism Xanthomonas campestris. Examples of commercially available xanthan gum are GRINDSTED Xanthan Clear80 (available from DuPont), GRINDSTED Xanthan MAS-SH (available from DuPont), SAN ACE (available from San-Ei Gen FFI Co.), KELTROL (available from CP Kelco) and ECHO GUM (available from DSP Gokyo Food & Chemical Co.).
The term “carboxymethyl cellulose” (abbreviated herein to “CMC”) is intended to indicate a cellulose derivative prepared by substituting hydrogen in some of the hydroxy groups on the anhydroglucose unit of the cellulose polymer with carboxymethyl groups (—CH2—COOH). Examples of commercially available carboxymethyl celluloses include GRINDSTED BEV130 available from DuPont), GRINDSTED BEV150 (available from DuPont), GRINDSTED BEV 350 (available from DuPont) and WALOCEL C (available from Dow Chemical Co.).
It has surprisingly been found that a two-step agglomeration process is capable of providing a readily dispersible hydrocolloid composition in the form of a powder.
In step (a) of the process, granular xanthan gum and CMC are dry-blended with maltodextrin powder. Maltodextrin is a water-soluble sugar which is easily dispersed in water and provides dilution and physical separation of the xanthan gum and CMC granules. The concentration of maltodextrin in the dry blend of step (a) is favourably in the range of 40-90% by dry weight, preferably 50-80% by dry weight.
It is the aim of the present process to provide a readily dispersible hydrocolloid composition which has a rheology that is suitable for the management of dysphagia which provides thickness to foods and drinks and improves swallowability of foods and drinks. In order to prevent aspiration, efforts are made to thicken smooth liquids for people with dysphagia. The degree of such thickening varies depending on the severity of the dysphagia of the individual patient, and specialists such as doctors, speech therapists (ST), nutritionists, or the like are required to adjust the thickening in accordance with the behaviour of the individual patients. The hydrated composition should show the following features:
It should exhibit non-Newtonian flow behaviour. It should show a relatively higher viscosity at lower shear rate as this will increase the residence time on the tongue.
It should exhibit a lower viscosity at a shear rate of 50-100 s−1 while flowing in the pharyngeal walls but still be sufficient to reduce the risk of aspiration when the liquid flows around the epiglottis.
It has generally been found possible to achieve a desired viscosity when the ratio of xanthan gum to carboxymethyl cellulose in step (a) is between 90:10 and 30:70, preferably between 85:15 and 40:60, more preferably between 80:20 and 50:50.
The total concentration of the two hydrocolloids in the dry blend of step (a) is favourably in the range of 10-60% by weight, preferably 20-50% by weight, of the dry blend.
The two-step agglomeration takes place in steps (b) and (c) of the present process. Agglomeration is a process where easily dispersible ingredients are added to the hydrocolloid granules and where, at the same time, the particle size is increased, which will typically also improve the dispersibility and reduce lumping. The enlarged particles are composed of multiple granules of the two hydrocolloids physically bound together with the easily dispersed binder ingredient (such as maltodextrin). Upon hydration and dissolution, the binder dissolves and separates the hydrocolloid granules, primarily as a result of disturbances and liquid diffusion in the liquid microenvironment around and within the agglomerates. Superior dispersibility has been found for those hydrocolloid compositions that have been prepared by a two-step agglomeration process as opposed to compositions prepared by a process where the solutions of calcium salt and maltodextrin are applied simultaneously, cf. Example 1 compared to Example 4.
In the present process, the agglomeration may be performed by spraying an aqueous solution of an easily dispersible ingredient onto the dry blend of the hydrocolloids and maltodextrin in a fluid bed (in particular a moving fluidized bed). The spray rate should be balanced with the drying rate and the shear in the equipment used and, in combination, these parameters control the size growth of the agglomerates. It will be readily apparent to the person skilled in the art that each of the process parameters may be adjusted to the equipment used in the process. In step (b) of the present process, the aqueous solution contains a calcium salt. It is currently believed that the presence of calcium delays hydration and consequently the stickiness of the hydrocolloids and therefore allows the hydrocolloid granules to disperse into water before they become sticky and disposed to form lumps. Examples of suitable calcium salts are calcium lactate, calcium propionate, calcium citrate and calcium chloride. It is preferred to include the calcium salt in a concentration that is close to the solubility limit of that particular calcium salt in question as this permits the spraying time to be reduced. A currently preferred calcium salt is calcium lactate in terms of resulting in the desired dispersibility of the hydrocolloid composition. The concentration of calcium lactate in the aqueous solution of step (b) may be, for example, up to 10%, preferably up to 9.1%, more preferably from 5% to 9.1%, for calcium lactate anhydrate and, for example, up to 15%, preferably up to 12.8%, more preferably from 5% to 12.8%, for calcium lactate, 5 H2O. Another calcium salt, calcium propionate, may be included in the aqueous solution of step (b) in a concentration of up to 15%. The concentration of the calcium salt in the final composition is typically in the range of 1-10% by dry weight of the composition, preferably in the range of 1-5% by dry weight of the composition.
In step (c) of the present process, the liquid solution sprayed onto the agglomerated particles prepared in step (b) comprises preferably maltodextrin, more preferably maltodextrin in a concentration close to the solubility limit of that particular grade of maltodextrin. Maltodextrin is available in different grades expressed as dextrose equivalents (DE) between 3 and 20. The higher the DE value, the shorter is the glucose chain and the higher the solubility. For instance, when the maltodextrin is maltodextrin with a DE value of 6, it may be included in the aqueous solution of step (c) in a concentration of 33.3%. The concentration of maltodextrin added to the composition in step (c) may be in the range of 2-20% by dry weight of the composition. The subsequent agglomeration with the maltodextrin solution is considered to be required to build and strengthen the agglomerates because the calcium salt is a poor binder and, if used alone, results in small and weak agglomerates, while maltodextrin provides stickiness and leads to stronger and larger agglomerates being formed in the process.
The agglomerated particles may be recovered by discharging them from the fluid bed. The particles typically have a particle size where 20-80% of the particles have a particle size of 200 μm or more, and at least 90% of the particles have a particle size of more than 50 μm. The particle size may be determined on a Malvern Mastersizer 3000 using Mie scattering model.
The resulting hydrocolloid composition is readily dispersible in water or an aqueous liquid. Dispersibility may be determined by placing a glass beaker (Ø 4 cm, provided with a 3 cm stirrer magnet) containing 100 ml model tap water (deionized water containing 0.025% by weight NaCl) on a magnetic stirrer. Then, 2 g of the agglomerated particles are poured into the glass beaker and the magnetic stirrer is turned on 2 seconds later. Stirring at 600 rpm is maintained for 10 seconds after which the magnetic stirrer is turned off. The degree of occurrence of lumps is assessed visually. The samples are rated from 1 to 5, where 1 means the appearance of very large poorly hydrated lumps, 2 means the appearance of large and medium-sized lumps, both well and poorly hydrated, 3 means the appearance of medium-sized and small lumps, both well and poorly hydrated, 4 means the appearance of a few small, well-hydrated lumps that dissolve within a few minutes, and 5 means that no lumps are present. A dispersibility of 3 is considered acceptable, while a dispersibility of 4 or 5 is preferred.
The hydrocolloid composition has a viscosity of 100-400 mPa·s at a shear rate of 50 s−1 when determined as a 2% by weight sample of the agglomerated particles in water. The viscosity range has been found to be effective for the management of dysphagia. The viscosity may be determined as follows:
Samples are prepared by slowly adding agglomerated particles to tap water in a beaker.
The samples are stirred at 500 rpm for 30 min. and then removed from the stirrer and a magnetic bar is added and the sample is stirred overnight.
The sample is left for at least 5 minutes without stirring before measuring flow curves (0.001 s−1 to 1000 s−1 at 20° C.) in a MCR501 rheometer (Anton Paar).
The agglomerated particles preferably have a bulk density of 20-50 g/100 ml when measured gravimetrically in a 100 ml glass cylinder (Ø ˜4 cm).
For use in the management of dysphagia, 1-3% by weight of the hydrocolloid composition comprising 20-50% by weight of hydrocolloids and 50-80% by weight of maltodextrin may suitably be dispersed in cold tap water immediately followed by stirring with a spoon to provide the desired viscosity. The present hydrocolloid composition may similarly be added to hot beverages such as tea, coffee, broth etc. in a suitable concentration to provide the desired viscosity.
According to another embodiment of the present invention, a use of a readily dispersible hydrocolloid composition, in the manufacture of a composition for management of dysphagia, is provided.
According to another embodiment of the present invention, a use of a readily dispersible hydrocolloid composition, in the manufacture of a composition for providing thickness to foods and drinks and improving swallowability of foods and drinks, is provided.
According to another embodiment of the present invention, a readily dispersible hydrocolloid composition for providing thickness to foods and drinks and improving swallowability of foods and drinks, is provided.
According to another embodiment of the present invention, a use of a readily dispersible hydrocolloid composition for management of dysphagia, is provided. According to one preferred embodiment of the present invention, the use of the present invention is non-therapeutic use.
According to another embodiment of the present invention, a use of a readily dispersible hydrocolloid composition for providing thickness to foods and drinks and improving swallowability of foods and drinks, is provided.
According to another embodiment of the present invention, a method for providing thickness to foods and drinks and improving swallowability of foods and drinks, comprising adding a readily dispersible hydrocolloid composition to the foods and drinks, is provided.
According to another embodiment of the present invention, a method for managing dysphagia, comprising allowing a person with dysphagia to ingest the foods and drinks added a readily dispersible hydrocolloid composition, is provided. Here, according to another preferred embodiment of the present invention, the method excludes medical interventions for humans.
The embodiment of the use, composition and method, as mentioned above can be performed in accordance with the description on the readily dispersible hydrocolloid composition and process for preparing the same of the present invention.
The invention is described in further detail in the following examples which are not in any way intended to limit the scope of the invention as claimed.
Prototypes were prepared at a batch size of 1000 g in a pilot scale fluid bed (Aeromatic Fielder MP1) with top spray, using a two-fluid nozzle (Schlick 970-S4) with a 1.0 mm liquid pipe.
300 g of the hydrocolloids (xanthan gum MAS-SH and CMC BEV 150, 50:50, both available from DuPont) was dry blended with 572 g of maltodextrin DE6 (Glucidex 6 IT, available from Roquette). Binder solutions were prepared by mixing calcium lactate or maltodextrin, respectively, into 80° C. preboiled deionized water after which the solutions were maintained at 65° C. throughout the subsequent spraying process.
The fluid bed was pre-heated with process air at 70° C. to an exhaust temperature of 27-32° C. The fluid bed was then charged with the dry blend of hydrocolloids and maltodextrin. When sufficient fluidization of the product bed was observed at 25 m3/h (1 minute), the agglomeration process was initiated by spraying 300 g of a first binder solution containing 9.1% by weight of calcium lactate anhydrate or 12.8% by weight of calcium lactate, 5 H2O in of water onto the dry blend. After the first binder solution had been sprayed onto the dry blend of hydrocolloids and maltodextrin to form the first agglomerate (for about 30-45 minutes), the second binder solution (100 g of maltodextrin dissolved in 200 g of water) was sprayed onto the first agglomerate for 30-45 minutes to form the second agglomerate.
In both agglomeration steps, the spray air had a pressure of 1.8 bar and a temperature of 45° C. The fluidizing air temperature was constant at 70° C. throughout the entire agglomeration process. The fluidizing process air flow was increased from 25 m3/h to 50 m3/h within the first 15 minutes of the process and maintained at 50 m3/h for the remainder of the process.
When all of the second binder solution has been added, the second agglomerate was immediately discharged from the fluid bed via the sampling hole in a Ø 20 mm tube using a custom-made vacuum system. The discharge was carried out while the agglomerate was fluidizing to avoid fines from the internal filter to drop into the agglomerate.
The resulting agglomerate had a bulk density of 25 g/100 ml and a dispersibility of 4 (as determined by the magnetic stirrer method described above).
An agglomerate containing the hydrocolloids xanthan gum MAS-SH and CMC BEV150 and maltodextrin was prepared as described in example 1 with the exception that the amount of aqueous solution was reduced to 150 g.
The resulting agglomerate had a bulk density of 19 g/100 ml and a dispersibility of 4 (as determined by the magnetic stirrer method described above).
An agglomerate containing the hydrocolloids xanthan gum MAS-SH and CMC BEV150 and maltodextrin was prepared as described in example 1 with the exception that the first binder solution contained 15% by weight of calcium propionate in 200 g of water.
The resulting agglomerate had a dispersibility of 4 (as determined by the magnetic stirrer method described above).
An agglomerate containing the hydrocolloids xanthan gum MAS-SH and CMC BEV150 and maltodextrin was prepared as described in example 1 with the exception that 9.1% by weight calcium lactate anhydrate or 12.8% by weight of calcium lactate, 5 H2O) and 50 g of maltodextrin was dissolved in 300 g of water and applied as a single binder solution.
The resulting agglomerate had a bulk density of 23.9 g/100 ml and a dispersibility of 2 (as determined by the magnetic stirrer method described above).
An agglomerate containing xanthan gum MAS-SH and CMC BEV150 blended with maltodextrin was prepared as described above with the exception that only one binder solution containing 100 g of maltodextrin in 200 g of water was applied.
The resulting agglomerate has a dispersibility of 3 (as determined by the magnetic stirrer method described above).
45 kg of the hydrocolloids (xanthan gum MAS-SH and CMC BEV150, 50:50) was dry blended with 85.73 kg of maltodextrin PINE-DEX #2AG (available from Matsutani Chemical Industry Co., Ltd.). 45 kg of a 12.8% w/w solution of calcium lactate, 5 H2O, was prepared as the first binder solution, and 45 kg of a 30% w/w maltodextrin solution was prepared as the second binder solution.
The agglomeration process was carried out under the following parameters:
Inlet air temperature: 70° C.
Outlet air temperature: 45-50° C.
Spray rate during calcium lactate addition: 0.55-0.67 kg/min (33-40 kg/h)
Spray rate during maltodextrin addition: 0.95 kg/min (57 kg/h)
After the full amount of calcium spray solution and then maltodextrin solution had been applied, post-drying was performed for about 5 minutes.
After opening the fluid bed for discharging, a layer of fines on top of the product bed was scraped away, and samples were taken for dispersibility testing. The resulting agglomerate had a dispersibility of 5 (as determined by the magnetic stirrer method described above).
Prototypes were prepared at a batch size of 1000 g in a pilot scale fluid bed (Aeromatic Fielder MP1) with top spray, using a two-fluid nozzle (Schlick 970-S4) with a 1.0 mm liquid pipe.
400 g of a 50:50 blend of the hydrocolloids (xanthan gum MAS-SH and one of the carboxymethyl celluloses: CMC BEV 150, available from DuPont; Blanose 7H3SF, available from Ashland; Walocel CRT 20000PA, available from the Dow Chemical Company) was dry blended with 498 g of maltodextrin DE20. Binder solutions were prepared by mixing calcium lactate or maltodextrin, respectively, into 80° C. preboiled deionized water after which the solutions were maintained at 65° C. throughout the subsequent spraying process.
The fluid bed was pre-heated with process air at 70° C. to an exhaust temperature of 27-32° C. The fluid bed was then charged with the dry blend of hydrocolloids and maltodextrin. When sufficient fluidization of the product bed was observed at 25 m3/h (1 minute), the agglomeration process was initiated by spraying 240 g of a first binder solution containing 9.1% by weight of calcium lactate anhydrate or 12.8% by weight of calcium lactate, 5 H2O in water onto the dry blend. After the first binder solution had been sprayed onto blend of hydrocolloids and maltodextrin to form the first agglomerate (for about 30-45 minutes), the second binder solution (240 g of a 33.3% maltodextrin solution in water) was sprayed onto the first agglomerate for 30-45 minutes to form the second agglomerate.
In both agglomeration steps, the spray air had a pressure of 1.8 bar and a temperature of 45° C. The fluidizing air temperature was constant at 70° C. throughout the entire agglomeration process. The fluidizing process air flow was increased from 25 m3/h to 50 m3/h within the first 15 minutes of the process and maintained at 50 m3/h for the duration of spraying the first binder solution. Fluidization air flow was increased to 60 m3/h for spraying the second binder solution.
When all of the second binder solution has been added, the second agglomerate was immediately discharged from the fluid bed via the sampling hole in a Ø 20 mm tube using a custom-made vacuum system. The discharge was carried out while the agglomerate was fluidizing to avoid fines from the internal filter to drop into the agglomerate.
The resulting agglomerate that included CMC BEV150 had a bulk density of 40 g/100 ml and a dispersibility of 4 (as determined by the magnetic stirrer method described above); the agglomerate that included Blanose 7H3SF had a bulk density of 50 g/100 ml and a dispersibility of 4 (as determined by the magnetic stirrer method described above); and the agglomerate that included Walocel CRT20000PA had a bulk density of 44 g/100 ml and a dispersibility of 3 (as determined by the magnetic stirrer method described above).
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-055510 | Mar 2019 | JP | national |
This application represents a national filing under 35 U.S.C. 371 of International Application No. PCT/JP2020/012465 filed Mar. 19, 2020, and claims priority of Japanese Patent Application No. 2019-055510 filed Mar. 22, 2019, the contents of both applications are incorporated herein by reference in their entirety for all purposes.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/012465 | 3/19/2020 | WO | 00 |
