Protein extraction from green crops

• US 4,359,530 A
• Filed: 09/08/1980
• Issued: 11/16/1982
• Est. Priority Date: 09/08/1980
• Status: Expired due to Term

• Current Assignee: Alcoa Incorporated (Howmet Aerospace, Inc.)
• Original Assignee: Aluminum Company of Egypt
• Inventors: Brown, Melvin H.
• Primary Examiner(s): Wiseman, Thomas G.
• Application Number:
  US06/185,177
• Time in Patent Office: 799 Days
• Field of Search: 435/68, 435/99, 435/105, 435/262, 435/267, 435/272, 435/274, 435/276-279, 435/801, 435/813, 435/136, 426/7, 426/48, 426/49, 426/52, 426/53, 426/54, 426/425, 426/656, 127/34, 127/36, 127/37, 162/14, 162/16, 162/97, 260/112 R
• US Class Current: 435/68.1
• CPC Class Codes: A23J 1/007 from leafy vegetables, e.g. alfalfa, clover, grass
• CPC Class Codes: Y10S 435/801 Anerobic cultivation
• CPC Class Codes: Y10S 435/813 Continuous fermentation
• CPC Class Codes: Y10S 530/859 Waste, waste material, refuse or sludge, e.g. effluents, fecal matter

Abstract

A method of extracting protein from green crops such as leaves, grasses, legumes, stems of green plants and tree leaves is disclosed. The method comprises the steps of subjecting the green crops to a pulping action in an acid solution recirculated from a subsequent anaerobic fermentation step to produce a pulp comprising a protein-rich liquid and fibrous material. The protein-rich liquid in the pulp is separated from the fibrous material. The protein is separated from the protein-rich liquid by anaerobic fermentation in an acidic solution thereby providing a concentrated protein fraction suitable for preservation and an acidic solution at least a portion of which is recycled to insure further removal of protein from the fibrous material.

Claims

1. A method of extracting protein from green crops, leaves, grasses, legumes, stems of green plants and tree leaves, comprising the steps of:

(a) subjecting the green crops, leaves, grasses, legumes, stems of green plants and tree leaves to a hammering action for purposes of rupturing plant cell walls, the hammering taking place in an organic acid solution, having a pH in the range of 3.0 to 5.5 and being recirculated from subsequent fermentation separation step (c) to produce a pulp comprising a protein-rich liquid and fibrous material, the solution being present in amounts sufficient to aid in hammering and maintaining fluidity of the pulp;

(b) separating protein-rich liquid in the pulp from the fibrous material;

(c) separating protein from the protein-rich liquid by fermentation using anaerobic naturally occuring microorganisms, the fermentation conducted in an acidic solution thereby providing a concentrated protein fraction suitable for preservation and an acidic solution; and

(d) recycling at least a portion of the acidic solution to the separation of step (b), the recycling of the solution being provided to insure further removal of protein from the fibrous material.

2. The method in accordance with claim 1 wherein the acidic solution is substantially free of protein and said solution is employed for purposes of washing protein remaining in the fibrous material after said separation step.

3. The method in accordance with claim 1 wherein the acidic solution of step (c) has a pH in the range of 3.0 to 5.5.

4. A method of extracting protein from green crops, leaves, grasses, legumes and stems of green plants, comprising the steps of:

(a) subjecting green crops, leaves, grasses, legumes, stems of green plants and tree leaves to a hammering action for purposes of rupturing plant cell walls, the hammering taking place in an organic acid solution used in subsequent fermentation step (c), the solution having a pH in the range of 3.0 to 5.5, the pulping action producing a pulp comprising a protein-rich liquid and fibrous material, the solution being present in amounts sufficient to aid in hammering and maintaining fluidity of the pulp;

(b) making an initial separation of protein-rich liquid from the fibrous material;

(c) separating the protein from the protein-rich liquid by fermentation using anaerobic naturally occurring microorganisms, the fermentation conducted in an acidic solution having a pH in the range of about 3.0 to 5.5;

(d) subjecting the fibrous material of step (b), after the initial separation of protein-rich liquid, to a wash treatment to remove protein entrained in said fibrous material, the wash treatment being performed with acidic solution recirculated from step (c); and

(e) recirculating acidic solution after said wash treatment to said pulping action to provide an acidic solution therein.