Process and apparatus for flaxseed component separation

Abstract

A continuous process for separating components of flaxseed is described. Flaxseed is dried to a moisture content of about 1% or less, after which is introduced into a separation chamber having an abrasive rotator therein. As the flaxseed passes over the abrasive rotator, contact with rotator separates the flaxseed components into hulls and kernels Hulls and kernels are separated and may be used in this form or processed farther. Hulls may be further processed by extraction with water and with hexane to remove flaxseed gum and oil, respectively. These two extractions may be done ill any order. The process results in a lignan-rich component of flaxseed, a gum extract and oil. These separate components of flaxseed may be used in products such as foods, personal care products or nutraceuticals.

1 . A continuous process for separating hulls and kernels of flaxseed comprising the steps of: 
 (a) drying the flaxseed to reduce the moisture content to about 1% or less;    (b) continuously introducing dried flaxseed into a separation chamber having an abrasive rotator therein;    (c) flowing the dried flaxseed past the abrasive rotator at a rate sufficient to allow dehulling of flaxseed during contact with the abrasive rotator, producing hulls and kernels; and    (d) separating the hulls and kernels.    
     
     
         2 . The process of  claim 1  wherein the flow rate is controlled by introducing an air current into the separation chamber in a direction counter to the flow direction of the flaxseed.  
     
     
         3 . The process of  claim 1  wherein the flow rate is controlled by introducing flaxseed halls into the separation chamber with the flaxseed.  
     
     
         4 . The process of  claim 1  wherein flaxseed flows through the separation chamber at a rate of about 250 grams/minute.  
     
     
         5 . The process of  claim 1  wherein a specific gravity separator is used to separate the hulls and kernels.  
     
     
         6 . The process of  claim 1  wherein an aspirator is used to separate the hulls and kernels.  
     
     
         7 . The process of  claim 1  wherein the separation chamber comprises a mesh surrounding the abrasive rotator for sieving the flaxseed as it is dehulled in the separation chamber.  
     
     
         8 . The process of  claim 7  wherein the mesh is from about 25 to about 50 mesh.  
     
     
         9 . The process of  claim 8  wherein the mesh is about 40 mesh.  
     
     
         10 . A flaxseed hull obtained according to the process of  claim 1 .  
     
     
         11 . A flaxseed kernel obtained according to the process of  claim 1 .  
     
     
         12 . A process for producing separate components from flaxseed hulls comprising the steps of: 
 (a) drying the flaxseed to reduce the moisture content to about 1% or less;    (b) continuously introducing dried flaxseed into a separation chamber having an abrasive rotator therein;    (c) flowing the dried flaxseed past the abrasive rotator at a rate sufficient to allow dehulling of flaxseed during contact with the abrasive rotator, producing hulls and kernels;    (d) separating the hulls and kernels;    (e) extracting the hulls to remove gun and oil, producing flaxseed gum, flaxseed hull oil and a lignan-rich component of flaxseed.    
     
     
         13 . A process according to  claim 12  wherein the step of extracting the hulls comprises extracting the hulls with water to remove flaxseed gum, producing a high-gum hull fraction and a low-gum bull fraction; and extracting the low-gum hull fraction with hexane to remove oil, producing flaxseed hull oil and a lignan-rich component of flaxseed.  
     
     
         14 . A process according to  claim 12  wherein the step of extracting the hulls comprises extracting the hulls with hexane to remove oil, producing a high-oil hull fraction and a low-oil hull fraction; and extracting the low-oil hull fraction with water to remove flaxseed gum, producing a high-,um hull fraction and a lignan-rich component of flaxseed.  
     
     
         15 . A lignan-rich component of flaxseed obtained according to the process of  claim 12   
     
     
         16 . The lignan-rich component of  claim 12  containing lignans in an amount of from about 2 to about 10 times the amount in the flaxseed.  
     
     
         17 . A product containing the lignan-rich component according to  claim 12 , said product being for use as food, for personal care or as a nutraceutical.  
     
     
         18 . The product according to  claim 17 , wherein the lignan-rich component is used as a nutraceutical for treatment or prevention of cancer.  
     
     
         19 . A high-gum hull fraction of flaxseed obtained according to the process of  claim 12 .  
     
     
         20 . A product containing the high-gum hull fraction of flaxseed according to  claim 19 , said product being for use as food, as a personal care product or as a nutraceutical.  
     
     
         21 . A flaxseed hull oil obtained according to the process of  claim 12 .  
     
     
         22 . A product comprising the flaxseed hull oil of  claim 21 , said product being for use as food, as a personal care product, or as a nutraceutical.  
     
     
         23 . An apparatus for separating hull and kernel components of flaxseed comprising: 
 a separation chamber into which dried flaxseed is introduced, said chamber having a flaxseed inlet and a flaxseed component outlet;    an abrasive rotator disposed within the separation chamber having an axis of rotation extending between the inlet to the outlet of the separation chamber, the abrasive rotator for contacting said flaxseed while rotating to breaking flaxseed into hulls and kernels;    a sieve disposed within the separation chamber surrounding the abrasive rotor for separating flaxseed components by size exclusion; and    a flow controller for allowing flaxseed to be maintained within the separation chamber until adequate separation of hull and kernel components is achieved.    
     
     
         24 . The apparatus of  claim 23  wherein the flow controller comprises a counter-flow air stream introduced into the separation chamber in a direction from the outlet to the inlet.  
     
     
         25 . The apparatus of  claim 23  additionally including an air classification apparatus for classifying hull and kernel components once flaxseeds are broken.