Formulation and Processing Strategies for Development of More Robust Microcapsules

Transcription

1 barrel molten material extrudate Formulation and Processing Strategies for Development of More Robust Microcapsules World Congress on Oils & Fats and 31 st Lectureship Series 31 st Oct 4 th November 2015, Rosario, Argentina CSIRO FOOD AND NUTRITION Luz Sanguansri and Mary Ann Augustin

2 Outline Introduction Capitalising on protein-carbohydrate functionality Formulation strategies Processing strategies Examples More robust compressible & extrudable powders Spray dried compressible formulations Extruded compressible formulations Opportunities

3 Status of microencapsulation development in the food industry Microencapsulation an enabling technology to incorporate reactive/ unstable ingredients into value added finished products In the last 20 years microencapsulation has Transformed the health and wellness industry Expanded the application of bioactives into nutraceuticals and medical foods Technology development and progress Established: Microencapsulation technology for stabilisation Developing: Target delivery and controlled release Future: More robust microcapsule formulations Source: Frost & Sullivan 2012

4 Market drivers & trends - Food Encapsulation Global Encapsulation Market* $39.5 billion in value by 2020 CAGR of 6.1% from 2015 Food encapsulation market size by Core / active ingredients* Market drivers Increased consumption of processed foods Rapid growth in functional foods Brand differentiations (use of microencapsulated ingredients) Use of microencapsulated ingredients reduces overage New product new opportunities Source: *

5 When is microencapsulation required? Bioactives / Core identified or chosen Is the ingredient stable in current form? NO YES Encapsulation & delivery systems required Encapsulated ingredients Ingredient not stable in final product Delivery systems not required Formulate directly into final product Application and formulation into final product Bioactives are generally not directly added to food, as the bioactive often needs protection prior to its release

6 What are the requirements for microencapsulation? Bioactive/Core requirements Safety in food Health benefits Encapsulant requirements Food grade (GRAS status) Ability to protect the bioactives from degradation Delivery and release the bioactive at target site for absorption Taste neutral will not affect sensory properties of the food Overall the cost and not the technology availability continues to be a limiting factor when it comes to adapting delivery systems technologies in the food industry.

7 Examples from literature: Formulation & processing strategies for lipophilic bioactives Delivery systems WPC (Whey protein concentrate)/cho > than WPC alone for encapsulation of milkfat NaCaseinate > Whey protein as encapsulant for 5-30% soy oil powders (based on ESCA) Addition of lactose to WPC stabilized soy oil emulsions Emulsion droplet structure maintained during drying Wettabiliy of powder is improved Type of sugar affects encapsulation efficiency NaCaseinate/CHO blends with higher DE (dextrose equivalent) are superior improved encapsulation Skim milk powder (SMP), WPI, WPC, NaCaseinate or combination SMP higher encapsulation efficiency than other milk protein or combinations due to presence of lactose Heated protein-cho are superior encapsulants than physical blends Improved oxidative stability of fish oils Reference Young et al., JDS1993 Faldt & Bergensthahl, Food Hydrocolloids, 1995 Faldt and Bergenstahl, Food Hydrocolloids, 1996 Hogan et al., IDJ 2001 Aghbashlo et al 2013, Food & Bioprocess Tech. Augustin et al., JFS 2006, Drusch et al., Food Hydrocolloids 2009

8 Capitalising on protein-carbohydrate functionality as encapsulant 8

9 How do we capitalise on proteins and carbohydrates functionality as encapsulants? Formulation strategies: Functionalising the protein/carbohydrate (alone or in blends) Capitalising on interactions for functionality Modification processes Conventional processing (eg. heat, shear) Emerging processes (e.g. high pressure, ultrasound) Results: new structure and functionality of protein/carbohydrate encapsulants improved physical and chemical stability and controlled release properties

10 Effect of formulation on moisture barrier properties Moisture Uptake Studies Use of Dynamic Vapour Sorption Higher MW CHO = better moisture barrier Globular protein = better moisture barrier Higher lipid content = better moisture barrier DVS Change In Mass (dry) Plot at 25C DVS Change In Mass (dry) Plot at 25C DVS Change In Mass (dry) Plot for Cas/Glu/Hylon(1:2)/Oil Cas-DGS-Oil Cas-RS-Oil Target RH WPI/Hylon(1:1)/50%oil Cas/Hylon(1:1)/50%oil Target RH 25%oil 50%oil Target RH Change In Mass (%) - Dry DVS - The Sorption Solution Time/mins Surface Measurement Systems Ltd UK Target RH (%) Change In Mass (%) - Dry Time/mins Target RH (%) Change In Mass (%) - Dry Time/mins Target RH (%) Activation Energy Activation Energy (Ea) at 25C 140 Cas-DGS-Oil Cas-RS-Oil Ea [kj/mol] Ea [kj/mol] %RH -> 30%RH 30%RH -> 60%RH 60%RH -> 90%RH 0 Cas/Glu/DGS(1:2)/25%oil Cas/Glu/DGS(1:2)/50%oil Materials with lower moisture sorption & higher activation energy = better moisture barrier Design moisture barrier properties and diffusion behaviour of the encapsulant for moisture sensitive cores

11 Modification of Resistant Starch Properties - as encapsulant ingredient RI response (mv) f e d c b a g HP-SEC profiles MW (molecular weight of pullulan) Estimated Molecular Weight Structural changes of Hylon VII by varoius processing methods 58% RS Raw Starch 35% RS Heated Ultrasonication 30% RS Heated MF % RS HPP/6000bar/15min Retention time (min) X-ray crystallographic profiles Heat/MF Hylon VII Raw Hylon VII Pre-processed Resistant Starch improved film forming & water binding properties CSIRO Technology, WO 2005/ A1

12 Modification of Mixed Biomaterial Properties - protein-carbohydrate conjugates (MRP) MRP conjugates: Improved antioxidant, film forming properties and excellent encapsulants for oxygen sensitive bioactives CSIRO s MicroMAX Technology, WO 01/74175 A1

13 Natural Cross-linking of Protein-polyphenols for controlled release Natural crosslinking chemistry using gelatin: Modified material properties enabling lower in-vitro degradation Potential of natural crosslinking chemistry to tailor the functionality of biomaterials Kosaraju S. et al 2009 (CSIRO presentation)

14 MicroMAX Food grade encapsulant for GI Tract delivery - Resistance of matrix & interface to digestion MRP Non-MRP NaCas-Glc- MFHylon MRP NaCas-Glc-MFHylon non-mrp SGF+SIF oil Encapsulant oil oil Encapsulant oil (no bile/ca) Before Digestion SGF In water powder After SGF+SIF digestion with Ca+Bile MATRIX RESISTANCE TO DIGESTION: Burgar et al. Food Biophysics (2009) Maillard encapsulants are more resistant to digestion INTERFACE STABILITY: Oliver et al. ADJT (2009) Maillard encapsulants are less prone to coalescence / loss of integrity of original interface Increased resistance to digestion confirmed in in-vitro GI tract model CSIRO MicroMAX-2 Technology, WO 2005/ A1

15 MicroMAX Food grade encapsulant for GI tract delivery - Protection of the oil core from digestion % Free Fatty Acids Fish Oil (66.67%) + Na Caseinate (33.33%) Fish Oil (50%) + Na Cas - raw Hylon VII (50%) Fish Oil (50%) + Na Cas - MF Hylon VII (50%) Non-heated Encapsulant Matrices Heated Encapsulant Matrices Chung et al., Food Biophysics, 2008 OIL CORE - DEGREE OF LIPOLYSIS Reduced with Maillard Encapsulant (IN IN-VITRO MODEL SYSTEM) OIL CORE - DEGREE OF LIPOLYSIS Reduced with Maillard Encapsulant (IN SIMULATED GI TRACT MODEL SYSTEM) Microencapsulation increased stability of the core in in-vitro model systems CSIRO MicroMAX-2 Technology, WO 2005/ A1

16 MicroMAX Process - capitalising on the Maillard Reaction to develop new food grade encapsulants CSIRO s MicroMAX Technology

17 MicroMAX Omega-3 oil powder - high oil loading and long shelf stability 25% oil 50% oil Aust & NZ 2002 Aust 2002 Aust 2002 Aust (AIFST Award 2003) 2003 Middle East UK & Europe 2006 Aust Aust & SE Asia MicroMAX Powder compared to Non-MicroMAX Powder Doubled the oil loading Doubled the shelf life Market Success in commercial food products with long shelf stability Extrusion & tabletting application remains a big challenge Extruded products: breakfast cereals, expanded snacks Tablets: supplements, multivitamins CSIRO s MicroMAX Technology; Augustin & Sanguansri 2013, OFI

18 Challenges and strategies in extrusion and tabletting application Challenges Oxidation stability Oil leakage from powder during processing (extrusion & compression) Low omega-3 level delivered per tablet Strategies include encapsulation High oil loading powder formulation with excellent stability Direct compressible formulations with very low excipients Use omega-3 oil concentrate with high amount of EPA & DHA

19 Example 1 Development of more robust spray-dried formulations Aim: Develop robust omega-3 powder formulation that can resist mechanical stresses during tablet compression or extrusion Hypothesis: Formulation and order of processing will microcapsule stability and performance during compression and extrusion 19

20 Compression testing & screening Experimental Set-up Instron Compression Test at 5 KN force: Oil Leakage (visual observation) Scale: 1 to 5 1 = no visible oil leakage 5 = very oily on the surface % Oil Leakage after compression = total oil in powder before compression total oil in tablet after solvent wash

21 Stability & compression testing of 50% oil powders Preliminary screening Oil Leakage F1 1.17% F2 1.23% F3 2.30% F4 3.39% F5 1.44% F6 1.61% Cas-DGS MicroMAX 10% oil leakage WPI-Cas-DGS MicroMAX 4.9% oil leakage Formulation & process optimisation can further improve robustness of powders during compression Ying, Shen, Cheng, Bhail, Sanguansri, Augustin 2013 CSIRO Report CSIRO s MicroMAX Technology

22 Protection of 50% oil powder during extrusion Surface oil of extruded product Control Encapsulant Ca Ca 0.8 Oil powder Surface oil % Aa Ab Ac Ba Bb Bc ABb %oil loading MicroMAX encapsulated oil powder protected the oil from leakage during extrusion up to 15 % oil addition no increase in surface oil compared to control Ying et al 2015, LWT Food Sci Tech 62,

23 Stability of 50% oil powder in extruded product (under accelerated storage condition) C barrel temperature 180 C die temperature oxygen pressure (bar) Neat Oil Extrudate with MicroMAX Encapsulated Oil powder Extrudate with MicroMAX Encapsulant plus neat Oil Extrudate with neat Oil Induction Period (IP) (hrs) Oxidative stability (IP) was enhanced when MicroMAX base was added, and was further enhanced when MicroMAX oil powder was added to the matrix Ying et al 2015, LWT Food Sci Tech, 62,

24 Results Highlights Oil leakage during powder compression was reduced from 10% to 1% with formulation and processing optimisation Microencapsulated omega-3 oil in heated proteincarbohydrate encapsulant (MicroMAX oil powder) can be added up to 15% in extruded product with very low surface oil Oxidative stability (IP) was significantly enhanced when MicroMAX encapsulated oil powder was added to the matrix

25 Example 2 Development of spray-dried compressible formulation Hypothesis: Multilayered interface will improve oil retention of microcapsule during tablet compression 25

26 Process variations in emulsion preparation Standard MicroMAX process Volume (%) Particle size (µm) Volume (%) Particle size (µm) Volume (%) Particle size (µm) Volume (%) Particle size (µm) 50µm 50µm 50µm Sanguansri et al, 2015, JAOCS (under review)

27 Surface oil, oil leakage on compression and headspace propanal (40 C, 14 wks) Headspace Propanal (area) Powder 1 Powder 2 Powder 3 Powder 4 6 weeks 12 weeks 14 weeks Powder 1 Powder 2 Powder 3 Powder 4 WPI-Cas-DGS MicroMAX WPI-Cas-DGS MicroMAX + 85 C 15min WPI-Cas-DGS MicroMAX + Pectin WPI-Cas-DGS MicroMAX + pectin / 85 C 15 min Extra heat treatment with/without pectin reduced powder surface oil, oil release on compression and headspace propanal after accelerated oxidation Extra heat treatment alone (Powder 2) without pectin has the lowest propanal content Sanguansri et al, 2015, JAOCS (under review)

28 Multilayered formulation performance Matrix + Process Oil content Oil Leakage Oil Leakage Visual 1=none; 5=oily IP (hrs) Oxipress Cas-DGS MicroMAX 50% 10% WPI-Cas-DGS MicroMAX 43% 4.9% WPI-Cas-DGS MicroMAX + 85 C 15min 43% 3.6% WPI-Cas-DGS MicroMAX + Pectin 43% 3.3% WPI-Cas-DGS MicroMAX + Pectin / 85 C 15 min 43% 2.9% Formulation and processing condition improved the stability and robustness of omega-3 stabilised by protein and/or carbohydrate matrices Sanguansri et al, 2015, JAOCS (under review)

29 Results Highlights Microencapsulated oil powders can be directly compressed into tablets without added excipients Microcapsule formulation and process improved oxidative stability of microencapsulated powders Formulation and process reduced oil leakage from 10% to 3% on compression of powders

30 Example 3 Development of Extruded compressible formulations Hypothesis: Embedding omega-3 oil powders in a protein matrix will improve oil retention of microcapsule during tablet compression 30

31 Preparation and testing of extrudable & compressible omega-3 microcapsules Dough characterisation Analyse: Oil leakage after compression Minimum water required for hydration of proteins & CHO 47%TS Formulation (53 % moisture) = 22.7% 60%TS Formulation (40% moisture) = 35.6% 70%TS Formulation (30% moisture) = 41.6% Ying et al, 2015, Powder Technol (under review)

32 Surface oil - Solvent extractable after extrusion and compression Processing Temperature Dough total solids 47% TS 60% TS 70% TS 0.14 % 4 % 1.77 % 22 % 4.30 % 27 % 20 C 35 C 0.43 % 0 % 0.79 % 8 % 3.79 % 21 % 50 C 0.12 % 3 % 2.56 % 19 % 3.55 % 24 % Total solids, viscosity and temperature to functionalise the dough has significant influence on robustness of the matrix Ying et al, 2015, Powder Technol (under review)

33 Extrudable & compressible formulations with 35% oil Complex viscosity (Pa.s) Sanguansri & Augustin CSIRO 70% total solid 60% total solid 47% total solid Oil Release after compression from extruded microcapsule pellets containing 35% oil Dough Temp Dough Total Solids 47% TS 60% TS 70% TS 20 C C Temperature (oc) 50 C Total solids, viscosity and temperature to functionalise the dough has significant influence on robustness of the matrix Luz Sanguansri CSIRO Ying et al 2015, Powder Technology (under review)

34 Results Highlights Microencapsulated omega-3 oil formulations can be extruded and directly compressed into tablets without added excipients Sufficient water is required to functionalise the proteins and carbohydrates as encapsulant for extrusion Total solids, viscosity and processing temperature has significant influence on performance of the microcapsules during tablet compression

35 Opportunities 35

36 Opportunities for tablettable formulations Global vitamin and supplement market - expected growth at 4% to reach $112 billion in 2018 Tablet format provides opportunity to add omega-3 to multivitamin formulations or bioactive cocktail Tablets lower cost than soft gel capsules capsules gummies Tablets have longer shelf life than soft gel or liquid format powder tablets

37 Opportunities for extrudable formulations in breakfast cereals and snack applications Extruded Snacks Market ($Million) *Bubble size indicates the market size, 2019-P ($Million) Omega-3 source from flax seed Extruded snack market is expected to increase to $31 billion by 2019 (MarketsandMarkets) Global breakfast cereal market is US$32.5 billion in 2012, expected to increase 14% to US$43.2 billion in 2019 special emphasis on healthier products

38 Acknowledgements ProjectTeam Members L Sanguansri Project Leader W Beattie S Bhail LJ Cheng K Pitts Z Shen S Udabage DY Ying Science Leadership MA Augustin T Lockett Many others along the way CSIRO colleagues University colleagues Students and visiting scientists Support: CSIRO & Preventative Health Flagship

39 Thank you for your attention Luz Sanguansri Research Team Leader Functional Ingredients & Bioactives Tel: luz.sanguansri@csiro.au Web: CSIRO FOOD AND NUTRITION