Patent GB-1502136-A (GB)
Title: Meat substitute products
IPC: A23J3/26
Filed: 1975-07-10
Abstract: 1502136 Extruded meat substitutes CENTRAL SOYA CO INC 10 July 1975 [2 Aug 1974] 29004/75 Heading A2B [Also in Divisions B4 and B5] An extruded meat substitute product of a solvent extracted oilseed protein material, which includes at least 40% by weight protein on a dry basis, comprises fibrous bundles of the material arranged in generally longitudinal alignment, and as stacked platelets between air pockets comprising less than 25% of the volume of the product and having the general contour of the platelets. The air pockets are of a largest dimension of less than 0.2 mm and comprise no more than 3 per sq. mm. The material is extruded as a mixture, comprising 30 to 60% by weight volume of water and, during extrusion, passes through a plurality of zones 1-3, Fig. 1, of the extruder which are of successively decreasing temperature and pressure, the zone 3 between the screw and the die orifice being at a tmperature and pressure of less than 212F and 100 p.s.i., e.g. giving a pressure drop across the die orifice of 70-80 p.s.i., and comprising an extrusion passage 14, 15, which has a cross-sectional area to length ratio of less than 10:1. Flow of material between the extrusion zones 1-2 is restricted by a screw collar 12, e.g. aligned with an extruder barrel collar, to produce higher residence time and pressure and shear in the zone 1, the screw in zone 2 being tapered and its thread being notched to slow down the flow of material and permit greater shearing with reduced pressure, and permitting a degree of expansion of the material, and the flow passage in zone 3 producing alignment of the fibrous material in the direction of extrusion.  The protein material may comprise defatted flours and concentrates derived from soybeans, peanuts, cotton and sesame seeds. The Examples include comparisons with the prior art processes, and relate to extrusion from a temperature jacketed extruder using a screw comprising seven zones separated by cylindrical screw collars aligned with cylindrical collars in the barrel, the extruded product being dried to 6-10% moisture content, for re-hydration prior to use. The materials of the examples comprise; examples (1), and (2), defatted soya flour of 50% protein content with, and without, seasoning, flavouring and colouring matter; (3), a soy protein concentrate e.g. of 70% or more protein, obtained from soy beans from which the oil has been extracted by hexane, and carbohydrate, minerals and soluble constituents extracted by 60-80% ethanol; (4), a 50:50 weight mixture of defatted soy flour and soy protein isolate obtained from defatted soybean flakes by treatment with mildly alkaline aqueous solution to extract soluble proteins, carbohydrates, and minerals, followed by acidification to precipitate the globulin fraction of the protein which was separated by centrifuging the resulting curd then being washed with water; dispersed with sodium. hydroxide, and then spray dried; (5), a 50:50 mixture of soy protein concentrate and soy protein isolate, the extruded product optionally being boiled prior to drying, and then being battered, breaded and fried to produce a product simulating sea food. The material of example (I) was also employed with stated proportions of other ingredients to produce a product simulating spiced and seasoned ground meat in tomato sauce, example (6), and a product simulating poultry, example (7), and chicken soup example (8).