Sweetening compositions and processes for preparing them

Abstract

The invention relates to sweetening compositions containing from about 16% to about 75% mogroside V and from about 30% to about 95% total terpene glycosides on a dry weight basis, and wherein a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v has an absorbance at 420 nm of about 0.55 or below. The invention also relates to methods of preparing such compositions.

1 . A sweetening composition, the composition containing from about 16% to about 75% mogroside V and from about 30% to about 95% total terpene glycosides on a dry weight basis, and wherein a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v has an absorbance at 420 nm of about 0.55 or below. 
     
     
         2 . A composition according to  claim 1 , wherein the terpene glycosides in the composition are naturally occurring terpene glycosides obtained from fruit of the Cucurbitaceae family. 
     
     
         3 . A composition according to  claim 1 , wherein the terpene glycosides in the composition are triterpene glycosides obtained from Luo Han Guo fruit. 
     
     
         4 . A composition according to  claim 1 , wherein substantially all of the solid components of the composition are obtained from Luo Han Guo fruit. 
     
     
         5 . A composition according to  claim 1 , wherein the composition contains from about 20% to about 70% mogroside V and from about 40% to about 90% total terpene glycosides, on a dry weight basis. 
     
     
         6 . A composition according to  claim 1 , wherein the composition contains about 30% to about 65% mogroside V and about 50% to about 85% total terpene glycosides, on a dry weight basis. 
     
     
         7 . A composition according to  claim 1 , wherein the composition contains about 35% to about 60% mogroside V and about 55% to about 85% total terpene glycosides, on a dry weight basis. 
     
     
         8 . A composition according to  claim 1 , wherein the composition contains about 40% to about 55% mogroside V and about 60% to about 80% total terpene glycosides, on a dry weight basis. 
     
     
         9 . A composition according to  claim 1 , wherein the absorbance at 420 nm of a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v is less than about 0.5. 
     
     
         10 . A composition according to  claim 1 , wherein the absorbance at 420 nm of a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v is less than about 0.4. 
     
     
         11 . A composition according to  claim 1 , wherein the absorbance at 420 nm of a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v is less than about 0.35. 
     
     
         12 . A composition according to  claim 1 , wherein the absorbance at 420 nm of a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v is less than about 0.3. 
     
     
         13 . A composition according to  claim 1 , wherein the absorbance at 420 nm of a filtered (0.2 μm) solution of the composition in water having a solids content of 1% w/v is from about 0.05 to about 0.25. 
     
     
         14 . A composition according to  claim 1 , wherein the composition is a powder. 
     
     
         15 . A composition according to  claim 1 , wherein the composition is a liquid. 
     
     
         16 . A composition according to  claim 15 , wherein the composition is an aqueous solution. 
     
     
         17 . A sweetening composition comprising:
 (a) a first component containing from about 16% to about 75% mogroside V and from about 30% to about 95% total terpene glycosides on a dry weight basis, and wherein a filtered solution (0.2 μm) of the first component in water having a solids content of 1% w/v has an absorbance at 420 nm of about 0.55 or below; and   (b) one or more additional components.   
     
     
         18 . A sweetening composition according to  claim 17 , wherein the additional components are selected from the group consisting of colouring agents, flavouring agents and other sweetening agents. 
     
     
         19 . A composition according to  claim 17 , wherein substantially all of the solid components of the first component are derived from fruit of the Cucurbitaceae family, preferably Luo Han Guo fruit. 
     
     
         20 . A beverage containing a sweetening composition according to  claim 1 . 
     
     
         21 . A food product containing a sweetening composition according to  claim 1 . 
     
     
         22 . A health care composition comprising a sweetening composition according to  claim 1 . 
     
     
         23 . A process of preparing a sweetening composition containing terpene glycosides, the process comprising the following steps:
 (a) obtaining a terpene glycoside-containing liquid extract from a fresh plant source material containing terpene glycosides;   (b) clarifying the extract;   (c) concentrating terpene glycosides in the extract to obtain a purified terpene glycoside-containing solution;   (d) heating the purified terpene glycoside-containing solution to a sufficient temperature and for a sufficient time to form melanoidins; and   (e) separating melanoidins from terpene glycosides in the solution to obtain a decolourised terpene glycoside-containing solution.   
     
     
         24 . A process according to  claim 23 , including the step of drying the decolourised terpene glycoside-containing solution obtained from step (e) to form a powdered composition. 
     
     
         25 . A process according to  claim 24 , wherein the decolourised terpene glycoside-containing solution obtained from step (e) is concentrated before final drying. 
     
     
         26 . A process according to  claim 23 , wherein the fresh plant source material is a fruit of the Cucurbitaceae family. 
     
     
         27 . A process according to  claim 23 , wherein the fresh plant source material is Luo Han Guo fruit. 
     
     
         28 . A process according to  claim 23 , wherein step (a) comprises contacting macerated Luo Han Guo fruit with hot water, at a sufficient time and for a sufficient temperature to extract triterpene glycosides from the fruit. 
     
     
         29 . A process according to  claim 28 , wherein the extraction is carried out using counter current extraction. 
     
     
         30 . A process according to  claim 23 , wherein the clarification step (b) comprises ultrafiltration of the extract. 
     
     
         31 . A process according to  claim 23 , wherein the liquid extract obtained from step (b) is filtered, centrifuged or decanted before step (c). 
     
     
         32 . A process according to  claim 23 , wherein the step (c) of concentrating terpene glycosides comprises (i) contacting the clarified extract with an adsorbent resin, wherein the adsorbent resin binds terpene glycosides in the extract; and (ii) eluting terpene glycosides from the resin to obtain a purified terpene glycoside-containing solution. 
     
     
         33 . A process according to  claim 32 , wherein the adsorbent resin used in step (c) is a macroporous polymeric adsorbent resin. 
     
     
         34 . A process according to  claim 32 , wherein the adsorbent resin used in step (c) is a styrene divinylbenzene copolymer or divinylbenzene copolymer resin. 
     
     
         35 . A process according to  claim 32 , wherein step (c) is carried out in a pressurised vessel. 
     
     
         36 . A process according to  claim 32 , wherein the terpene glycosides are eluted from the adsorbent resin with an aqueous solution of ethanol. 
     
     
         37 . A process according to  claim 36 , wherein the elution comprises a plurality of elution steps using ethanol solutions of increasing ethanol concentration. 
     
     
         38 . A process according to  claim 36 , wherein the heating step (d) comprises heating the terpene-glycoside containing ethanol solution(s) obtained from step (c), to both promote formation of melanoidins and evaporate ethanol, thereby allowing recovery of the ethanol. 
     
     
         39 . A process according to  claim 23 , wherein step (d) comprises heating the purified terpene glycoside-containing solution to a temperature of about 80° C. to about 120° C., for a period of time sufficient to form melanoidins. 
     
     
         40 . A process according to  claim 39 , wherein the heating is carried out at a temperature of about 80° C. to about 100° C., for a period of time of about 120 minutes to about 45 minutes. 
     
     
         41 . A process according to  claim 23 , wherein the decolourising step (e) comprises contacting the terpene glycoside and melanoidin-containing solution from step (d) with a decolourising resin which binds the melanoidins, to obtain a decolourised terpene glycoside-containing solution. 
     
     
         42 . A process according to  claim 41 , wherein the decolourising resin used in step (e) comprises a highly porous, macroporous, type I, strongly basic anion resin. 
     
     
         43 . A process according to  claim 41 , wherein step (e) is carried out in a pressurised vessel. 
     
     
         44 . A process of preparing a sweetening composition from a fresh plant source material containing terpene glycosides, characterized in that the process includes the steps of:
 (a) heating a terpene glycoside-containing sohidon to a sufficient temperature and for a sufficient time to form melanoidins; wherein the terpene glycoside-containing solution has been obtained by a process comprising the steps of extracting terpene glycosides from the plant source material and subsequently clarifying the solution by removing pectin and proteins;   (b) separating the melanoidins from the terpene glycosides in the extract to obtain a decolourised terpene glycoside-containing solution.   
     
     
         45 . A process according to  claim 44 , wherein the terpene glycoside-containing solution used in step (a) is obtained by an extraction process comprising the steps of contacting maccrated Luo Han Guo fruit with hot water, at a sufficient time and for a sufficient temperature to extract triterpene glycosides from the fruit. 
     
     
         46 . A process according to  claim 45 , wherein the contacting is carried out using countercurrent extraction. 
     
     
         47 . A process according to  claim 45 , wherein the clarification step comprises ultrafiltration of the extract. 
     
     
         48 . A process according to  claim 45 , wherein step (b) comprises contacting the resulting terpene glycoside- and melanoidin-containing solution with a decolourising resin that binds melanoidins (and optionally other non-terpene glycoside molecules in the solution). 
     
     
         49 . A process according to  claim 45 , including the step of concentrating terpene glycosides in the solution. 
     
     
         50 . A process according to  claim 49 , wherein the concentrating step comprises (i) contacting the clarified extract with an adsorbent resin, wherein the adsorbent resin binds terpene glycosides in the extract; and (ii) eluting terpene glycosides from the resin to obtain a purified terpene glycoside-containing solution. 
     
     
         51 . A process according to  claim 50 , wherein the adsorbent resin used in the concentration step is a macroporous polymeric adsorbent resin, such as a styrene divinylbenzene copolymer, or divinylbenzene copolymer resin. 
     
     
         52 . A process according to  claim 45 , including the step of drying the decolourised terpene glycoside-containing solution obtained from step (b) to form a powdered composition. 
     
     
         53 . A sweetening composition obtained by a process according to  claim 23 . 
     
     
         54 . A food product or a beverage containing a sweetening composition obtained by a process according to  claim 23 .