Methods and systems for recovering protein powder and natural omega-3 oil from animal tissue

Abstract

Provided are methods and systems for recovering protein product powder, purified water and omega-3 oil from an animal tissue. The methods and systems use high throughput extraction filtration separation systems. Animal tissue, for example fish, and organic solvent are directly or indirectly transferred into one of the optional extraction or filtration systems. The extraction-filtration systems provide a high degree of filtration performance and product washing efficiency. Each system ultimately yields a product wet cake that includes the protein product. The protein product wet cake is then further dried in a drying unit to yield the final protein powder product. In each system, the process filtrates undergo further processing by filtration and distillation to recover the organic solvent and separate out the omega-3 fish oil. The recovered organic solvent can be recycled back into the process. Solid protein product powder is thus recovered, along with omega-3 oil, purified water and recovered solvent.

What is claimed is: 
     
         1 . A system for recovering a protein product powder, an omega-3 oil and water from an animal tissue, comprising:
 a) a grinding unit;   b) a slurry preparation unit;   c) a dewatering device;   d) a closed system product separation system for separating the slurry into a liquid phase and a solid phase, the filtration system including a continuous conveyance filtration system selected from among a belt filtration system, a rotary drum filter, an immersion extractor, a percolator extractor, a decanter/centrifuge and a screw press and a combination thereof; and   e) a solvent/liquid recovery (SLR) system comprising:
 a liquid phase processing unit; 
 a separation unit that separates the liquid phase into recovered organic solvent, water and an omega-3 oil; and 
 a recovered organic solvent storage tank. 
   
     
     
         2 . The system of  claim 1 , further comprising a drying unit. 
     
     
         3 . The system of  claim 1 , further comprising a milling unit. 
     
     
         4 . The system of  claim 1 , wherein the system is automated. 
     
     
         5 . The system of  claim 4 , wherein the system is automated by using a programmable logic controller (PLC) and a customizable recipe-driven software architecture, wherein the PLC is the automated programmable device for controlling the process automatically without the need for manual intervention. 
     
     
         6 . The system of  claim 1 , wherein the separation unit includes a distillation unit or a centrifugation unit or a combination thereof. 
     
     
         7 . The system of  claim 6 , wherein the distillation unit comprises a distillation column, a thin film evaporator or a wiped film evaporator or any combination thereof. 
     
     
         8 . The system of  claim 6 , further comprising a process control system that analyzes the overhead vapor pressure and the temperature of the distillation unit. 
     
     
         9 . The system of  claim 1 , wherein the liquid phase processing unit comprises an adsorber system or an activated carbon filtration system or both. 
     
     
         10 . The system of  claim 9 , further comprising an analyzer system. 
     
     
         11 . The system of  claim 10 , wherein the analyzer system analyzes the adsorber effluent stream for detection free amines or small chain hydrocarbon materials. 
     
     
         12 . The system of  claim 1 , wherein the slurry preparation unit comprises a preparation tank for receiving and mixing ground animal tissue from the grinding unit with a solvent to form a slurry. 
     
     
         13 . The system of  claim 1 , further comprising a closed system recycling solvent loop that transports recovered organic solvent from the recovered organic solvent storage tank to slurry preparation unit. 
     
     
         14 . The system of  claim 1 , further comprising a volatile organic carbon recycling system that:
 captures process emissions of the organic solvent to form a condensed liquid solvent from the filtration process via condensation; and   transports the condensed liquid solvent to the closed loop recycler.   
     
     
         15 . The system of  claim 1 , wherein speed of the conveyance filtration system is controlled using a variable frequency drive (VFD). 
     
     
         16 . A method for recovering protein product powder and omega-3 oil from an animal tissue, comprising:
 mixing the animal tissue with an organic solvent in a preparation tank;   comminuting the animal tissue with the organic solvent to produce a slurry;   separating the slurry into a liquid phase and a solid phase using a filtration system selected from among a belt filtration system, a rotary drum filtration system, an immersion extraction system, a percolation extraction system and a screw press filtration system and any combination thereof;   recovering the liquid phase and separating it into a recovered organic solvent portion and an omega-3 oil portion;   recovering the solid phase and drying it to yield a protein wetcake; and   milling the protein wetcake to yield protein product powder.   
     
     
         17 . The method of  claim 16 , wherein the animal tissue includes raw fish that is processed through a dewatering device to remove excess water prior to mixing with the organic solvent. 
     
     
         18 . The method of  claim 16 , wherein the organic solvent mixed with the animal tissue includes an alcohol, an aliphatic hydrocarbon, an ester, water or any combination thereof. 
     
     
         19 . The method of  claim 16 , further comprising:
 capturing the vapor produced during drying the solid phase;   condensing the vapor into a liquid; and   separating the organic solvent from the liquid.   
     
     
         20 . The method of  claim 19 , wherein the wherein the organic solvent mixed with the animal tissue includes at least a portion of the recovered organic solvent derived from the condensed vapor derived from the drying step of an earlier processed slurry. 
     
     
         21 . The method of  claim 16 , wherein the milling is via a jet mill. 
     
     
         22 . The method of  claim 16 , wherein:
 the yield of protein is about 18 wt % or greater based on the total weight of the starting animal tissue; or   the yield of protein is from about 10 wt % to about 20 wt % based on the total weight of the starting animal tissue.   
     
     
         23 . The method of  claim 16 , wherein the protein product powder has a moisture content of less than about 10 wt %. 
     
     
         24 . The method of  claim 16 , wherein the protein product powder has an amount of residual organic solvent of less than about 0.5 wt %. 
     
     
         25 . The method of  claim 16 , wherein the amount of protein in the protein product powder is in the range of from about 45 wt % to about 96 wt %. 
     
     
         26 . The method of  claim 25 , wherein the protein product powder has a protein content from about 90 wt % to about 96 wt %. 
     
     
         27 . The method of  claim 16 , wherein the protein product powder has a crude fat content of less than about 1.5 wt %. 
     
     
         28 . The method of  claim 16 , wherein the protein product powder has a cholesterol content of less than about 0.1 wt %. 
     
     
         29 . The method of  claim 16 , further comprising separating water from the liquid phase. 
     
     
         30 . A protein product produced by the method of  claim 16 . 
     
     
         31 . The system of  claim 1  configured for installation on a marine vessel.