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
Outline Background: Can microalgae be processed into food? Overview: ph-shift process Results: solubility of Nannochloropsis protein Results: Product characterization Summary 2
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
The ph-shift process Isolation of proteins OH - OH - - OH - - NH - - 2 OH - COO - - - - OH - OH - +/- 4
ph-shift on Nannochloropsis Protein solubility, solubilization step percentage of protein (S1/lysate) 120 100 80 60 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 ph 5
ph-shift on Nannochloropsis Protein solubility, precipitation step percentage of protein (S2/S1) 18 16 14 12 10 8 6 4 2 0 1 2 3 4 5 ph ph 7 ph 10 Preliminary process: Solubilization at ph 7 Precipitation at ph 3 6
ph-shift product composition lysate ph 7/3 Dry/wet (%) 10 13 Protein/dry (%) 19 23 Total fatty acids/dry (%) 11 12 Carbohydrates/dry (%) 37 42 Ash/dry (%) 34 25 yields Protein (%lysate) P2, ph 7/3 86 85 Lipid (%lysate) 7
Summary: ph-shift with seawater Nannochloropsis proteins High solubility (80 100 %) 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
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) 95-102. 9
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) 145-153. A. Schwenzfeier, P.A. Wierenga, H. Gruppen, Isolation and characterization of soluble protein from the green microalgae Tetraselmis sp, Bioresour. Technol., 102 (2011) 9121-9127. M.A. Devi, L.V. Venkataraman, Functional Properties of Protein Products of Mass-Cultivated Blue- Green Alga Spirulina Platensis, J. Food Sci., 49 (1984) 24-27. I.S. Chronakis, Biosolar Proteins from Aquatic Algae, in: G. Doxastakis, V. Kisseoglou (Eds.) Novel Macromolecules in Food Systems, Elsevier, Amsterdam, Netherlands, 2000. 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) 51-57. Image sources: Presenting author, except for salt shaker "Salt shaker on white background" by Dubravko Sorić SoraZG on Flickr - http://www.flickr.com/photos/ 11939863@N08/3793288383/in/photostream/. Licensed under CC BY 2.0 via Commons - https:// commons.wikimedia.org/wiki/file:salt_shaker_on_white_background.jpg#/media/ File:Salt_shaker_on_white_background.jpg 10
Amino acid profile sum 235 265 sum nonessential 137 151 sum essential 97 114 P2, ph lysate P2, ph 7 lysate 7 mg/g mg/g mg/g mg/g Alanine 16 18 Lysine 15 18 Arginine 15 17 Methionine 4,3 5,5 Aspartic acid 21 24 Phenylalanine 12 14 Cystein + Cystine 2,5 2,7 Proline 24 22 Glutamic acid 26 29 Serine 11 12 Glycine 14 15 Threonine 12 13 Histidine 4,4 5,5 Tryptophane (total) 4,1 4,8 Isoleucine 10 12 Tyrosine 8,8 10 Leucine 20 24 Valine 15 17 11
Fatty acid profile lysate, ph 7 P2, ph 7 mg/g mg/g sum 105 123 C12:0 0,3 0,4 C14:0 5,5 6,7 C15:0 0,4 0,4 C16:0 29 34 C16:1 n7 32 37 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 n3 19 23 12
ph-shift on Nannochloropsis Lipid partitioning, ph 7 P1 P2 S1 S2 Lipid partitioning, ph 10 P1 P2 S1 S2 13