referring to fig1 , there is illustrated schematically a flow sheet of one embodiment to the invention . canola oil seed meal and aqueous extraction medium are fed by lines 10 and 12 respectively to a blender 14 wherein the oil seed meal and aqueous extraction medium are mixed and the mixture is passed by line 16 to a mixing pipe 18 . in the mixing pipe 18 , the oil seed meal is extracted and an aqueous protein solution is formed . the slurry of aqueous protein solution and residual oilseed meal is passed by line 20 to a vacuum filter belt 22 for separation of the residual oil seed meal which is removed by line 24 . the aqueous protein solution then is passed by line 26 to a clarification operation 28 wherein the aqueous protein solution is centrifuged and filtered to remove fines , which are recovered by line 30 . the clarified aqueous protein solution is pumped by line 32 through ultrafiltration membranes 34 sized to provide the desired degree of concentration of the aqueous protein solution to produce a concentrated protein solution as the retentate in line 36 with the permeate being recovered by line 38 . the concentrated protein solution is passed into the inlet of a mixing tee 40 , with cold water being fed thereto by line 42 in a volume sufficient to achieve the desired degree of dilution . the resulting solution is fed by line 44 to a settling tank 46 to permit the protein micellar mass to settle . protein micellar mass settled in the settling vessel 46 is removed by line 48 from time to time and passed through a spray dryer 50 to provide dry canola protein isolate 52 . supernatant from the settling tank is removed by line 54 and pumped through ultrafiltration membranes 52 to produce a concentrated protein solution as the retentate in line 58 with the permeate being removed by line 60 . the concentrated protein solution is passed through a spray dryer 62 to provide further dry canola protein isolate 64 . as an alternative , the concentrated protein solution in line 58 may be passed by line 66 to mix with the protein micellar mass before the mixture then is dried in spray dryer 50 . this example illustrates a continuous process for the production of canola protein isolate in accordance with one embodiment of the invention . 200 g of canola meal was added to 1350 ml ( 15 % w / v ) of a 0 . 15m sodium chloride solution at 50 ° c . the resulting mixture was passed through tubing of a sufficient length to give 5 minutes total residence time of the mixture in the tubing . analysis of the extract leaving the tubing showed a protein content of 20 . 5 g / l . by way of contrast , in a batch mode , salt solubilization ( 0 . 15 m nacl ) of a 15 % w / v solution of canola meal achieved a protein content of 18 . 3 g / l after 30 minutes of mixing at 24 ° c . ( run bw - ah014 - h29 - 01a ). 8 litres of a concentrated retentate with a protein content of 296 g / l was prepared by a batch procedure as described in example 2 ( see bw - ah014 - h29 - 01a ). the concentrated retentate , at a temperature of 30 ° c ., was pumped into one inlet of a t - shaped connection pipe at a rate of 64 ml / minute to mix with 4 ° c . water pumped into the other inlet of the t - shaped connection pipe at a rate to provide a dilution ratio of 1 : 10 . the t - shaped connector served as a device to mix the two streams and to cause the formation of a white cloud of protein micelles . the mixture then passed from the outlet from the t - shaped connection pipe into a 50 litre settling vessel filled with 4 ° c . water where the mixture exited the pipe through a outlet designed to minimize turbulence in the settling vessel . supernatant was removed from the top of the settling vessel maintaining the vessel at a constant volume . the system ran for two hours . as the retentate / water mixture flowed into the settling vessel a boundary layer began to form between micelles and the supernatant . this layer moved upwards in the vessel for the first hour after which it began to settle . at the same time , a layer of precipitated , viscous sticky mass ( pmm ) was visible at the bottom of the settling vessel . as the run progressed , the pmm layer grew steadily in volume . the boundary layer between the settling micelles and the supernatant steadied at a level approximately even with the retentate / water outlet . the supernatant as it exited the settling vessel was clear and there were no visible micelles in the supernatant being removed . the pmm removed from the bottom of the vessel following the settling period had a solids content of 29 . 8 wt % and represented 49 wt % of the protein in the retentate . by way of the contrast , in a batch mode , 40 litres of concentrated retentate with a protein content of 283 g / l at a temperature of 30 ° c . was diluted 1 : 10 into 4 ° c . tap water and the micelles were allowed to settle for 1 hour . the pmm recovered from the bottom of the vessel had a solids content of 36 . 2 wt % and represented 42 wt % of the protein in the retentate ( run bw - ah014 - 105 - 01a ) ( see example 2 ). this example provides details of the batch procedures described in the preceding example . “ a ” kg of concentrated canola meal was added to “ b ” l of 0 . 15 m nacl solution at ambient temperature and agitated for “ c ” minutes to provide an aqueous protein solution having a protein content of “ d ” g / l . the residual canola meal was removed and washed on a vacuum filter belt . the resulting protein solution was clarified by centrifugation to produce a clarified protein solution having a protein content of “ e ” g / l . the protein extract solution was reduced in volume on an ultrafiltration system using membranes having a molecular weight cut - off of 3000 daltons . the resulting concentrated protein solution had a protein content of “ f ” g / l . the concentrated solution at “ g ”° c . was diluted 1 : 10 into 4 ° c . tap water . a white cloud formed immediately and was allowed to settle . the upper diluting water was removed and the precipitated , viscous , sticky mass was dried . the product was given designation “ h ”. the specific parameters “ a ” to “ h ” for the different samples of protein product are set forth in the following table i : this example illustrates the application of the continuous extraction stage of the continuous process to mustard , non - gmo canola , high euricic acid rapeseed ( h . e . a . r . ), white flake canola meal and cold pressed canola meal . oil seed meals were added to separate 500 ml aliquots of 55 ° c ., 0 . 15 m nacl solution to provide mixtures having the following concentrations : mustard , high euricic acid rapeseed and a non - gmo canola : 15 % w / v a white flake and cold pressed canola meal : 10 % w / v the mixtures were pumped through a pipe having a length permitting a 5 minute extraction time in the pipe . samples were analyzed for protein content as soon as exiting the pipe . the results obtained are set forth in the following table ii : this example illustrates the application of the continuous dilution stage of the continuous process to mustard , non - gmo canola , high euricic acid rapeseed , white flake canola meal and cold pressed canola meal . extraction of oil seed meals were performed in 0 . 15 m nacl solution at room temperature with a 30 - minute mixing period for each oil seed meal . the seed concentrations were 10 % w / v for white flake and cold pressed canola meals and 15 % w / v for h . e . a . r ., non - gmo canola meal and mustard meal . following the 30 - minute mixing period , the solid material was separated from the extraction protein solution by centrifugation at 10 , 000 × g for 10 minutes . the protein solutions were further clarified by filtering through whatman # 4 filter papers on a vacuum filter apparatus . each clarified was concentrated on a amicon mini stirred - cell concentration system using membranes of mwco sufficient to retain the soluble protein while allowing water and contaminating small molecular weight material to pass through the permeate . each protein solution was concentrated to 200 mg / ml or greater . following concentration , the retentates were diluted in a continuous manner by using two peristaltic pumps and a t - shaped connector . the pump speeds were adjusted to allow the first pump to move fluid at a rate 10 times faster than the first pump , to provide a dilution ratio of retentate to water of 1 : 10 . the pumps were started simultaneously and the retentates and water were pumped into a common line through the t - shaped connector where they were mixed and micelle formation commenced . the resulting solutions were then passed into settling tanks where the precipitates were allowed to settle . pellets of settled pmm were collected and freeze dried to calculate yield and protein content of each pmm formed . the results obtained for each seed are set forth in tables iii and iv below : ( 1 ) protein content was determined as kjeldahl nitrogen × 6 . 25 . all pmm products formed were protein isolates . ( 2 ) yield was determined as the proportion of the protein extracted which was recovered as pmm . in summary of this disclosure , the present invention provides a continuous process for the production of oil seed protein isolate . modifications are possible within the scope of the invention .
oil seed protein isolates , particularly canola protein isolate , are produced continuously from oil seed meals , preferably at a high purity level of at least about 100 wt % , by a process wherein oil seed protein is continuously extracted from oil seed meal , the resulting protein solution is continuously concentrated , preferably to a protein content of at least about 200 g / l , and the concentrated protein solution is continuously mixed with chilled water having a temperature below about 15 ° c . to form protein micellar , which are settled in the settling vessel to provide a protein micellar mass while supernatant overflows the vessel . the pmm , when accumulated to a desired degree , may be separated from supernatant and dried . the supernatant may be processed to recover additional oil seed protein isolate .