ph-shift processing of Nannochloropsis to obtain a protein-enriched food or feed ingredient

Transcription

1 ph-shift processing of Nannochloropsis to obtain a protein-enriched food or feed ingredient Algae Biomass Summit Lillie Cavonius, lillie@chalmers.se Divisions of Food Science & Industrial Biotechnology Department of Biology and Biological Engineering Chalmers University of Technology Gothenburg, Sweden 2015-Oct-02

2 Outline Background: Can microalgae be processed into food? Overview: ph-shift process Results: solubility of Nannochloropsis protein Results: Product characterization Summary 2

3 Aims Vision Food & feed from Nannochloropsis Cheap and scalable process Minimal processing Wet algae (i.e. only partially dewatered) Study Protein solubility Preliminary process Characterization of product 3

4 The ph-shift process Isolation of proteins OH - OH - - OH - - NH OH - COO OH - OH - +/- 4

5 ph-shift on Nannochloropsis Protein solubility, solubilization step percentage of protein (S1/lysate) ph 5

6 ph-shift on Nannochloropsis Protein solubility, precipitation step percentage of protein (S2/S1) ph ph 7 ph 10 Preliminary process: Solubilization at ph 7 Precipitation at ph 3 6

7 ph-shift product composition lysate ph 7/3 Dry/wet (%) Protein/dry (%) Total fatty acids/dry (%) Carbohydrates/dry (%) Ash/dry (%) yields Protein (%lysate) P2, ph 7/ Lipid (%lysate) 7

8 Summary: ph-shift with seawater Nannochloropsis proteins High solubility ( %) between ph 6 and 10 Low solubility (< 10%) below ph 4 Process Solubilize at ph 7 (native), precipitate at ph 3 Removes water and ash Conc. of protein, lipids, carbohydrates slightly increased 8

9 Acknowledgements Funding Chalmers Kristina Stenborgs Stiftelse Supervisors Prof. Ingrid Undeland Assoc. prof. Eva Albers Colleagues at Food & Nutrition Science Industrial Biotechnology Full paper: L.R. Cavonius, E. Albers, I. Undeland, phshift processing of Nannochloropsis oculata microalgal biomass to obtain a protein-enriched food or feed ingredient, Algal Research, 11 (2015)

10 References Previous ph-shift on microalgae: J.A. Gerde, T. Wang, L.X. Yao, S. Jung, L.A. Johnson, B. Lamsal, Optimizing protein isolation from defatted and non-defatted Nannochloropsis microalgae biomass, Algal Res., 2 (2013) A. Schwenzfeier, P.A. Wierenga, H. Gruppen, Isolation and characterization of soluble protein from the green microalgae Tetraselmis sp, Bioresour. Technol., 102 (2011) M.A. Devi, L.V. Venkataraman, Functional Properties of Protein Products of Mass-Cultivated Blue- Green Alga Spirulina Platensis, J. Food Sci., 49 (1984) I.S. Chronakis, Biosolar Proteins from Aquatic Algae, in: G. Doxastakis, V. Kisseoglou (Eds.) Novel Macromolecules in Food Systems, Elsevier, Amsterdam, Netherlands, Protein quantification method: S.P. Slocombe, M. Ross, N. Thomas, S. McNeill, M.S. Stanley, A rapid and general method for measurement of protein in micro-algal biomass, Bioresour. Technol., 129 (2013) Image sources: Presenting author, except for salt shaker "Salt shaker on white background" by Dubravko Sorić SoraZG on Flickr @N08/ /in/photostream/. Licensed under CC BY 2.0 via Commons - commons.wikimedia.org/wiki/file:salt_shaker_on_white_background.jpg#/media/ File:Salt_shaker_on_white_background.jpg 10

11 Amino acid profile sum sum nonessential sum essential P2, ph lysate P2, ph 7 lysate 7 mg/g mg/g mg/g mg/g Alanine Lysine Arginine Methionine 4,3 5,5 Aspartic acid Phenylalanine Cystein + Cystine 2,5 2,7 Proline Glutamic acid Serine Glycine Threonine Histidine 4,4 5,5 Tryptophane (total) 4,1 4,8 Isoleucine Tyrosine 8,8 10 Leucine Valine

12 Fatty acid profile lysate, ph 7 P2, ph 7 mg/g mg/g sum C12:0 0,3 0,4 C14:0 5,5 6,7 C15:0 0,4 0,4 C16: C16:1 n C17:0 0,3 0,4 C17:1 0,3 0,4 lysate, ph 7 P2, ph 7 mg/g mg/g C18:0 0,4 0,5 C18:1 n9 7,9 9,5 C18:1 n7 0,4 0,5 C18:2 n6 3,5 4,2 C18:3 n6 0,4 0,5 C20:4 n6 5,2 6,2 C20:5 n

13 ph-shift on Nannochloropsis Lipid partitioning, ph 7 P1 P2 S1 S2 Lipid partitioning, ph 10 P1 P2 S1 S2 13