Investigation of diffusion ouf of different fat matrices – especially for iron in palm fat

1. Investigation ofdiffusionoufof different fatmatrices – especiallyforiron in palmfat Master Thesis Presentation of Vincent Keehnen Supervisor: Christina Käppeli Co-Referee: Dr. Hanselmann Referee: Prof. Windhab

2. Presentation structure Introduction Objectives Methods Results Discussion Summary Outlook D-AGRL, IFNH, Laboratory of Food Process Engineering

3. Introduction Iron deficiency affects 2 billion people worldwide  especially severe in Third World Countries1 Damages physical performance, cognitive abilities, immune system  severe impact on individual health and national productivity2 One strategy to combat iron deficiency: Iron supplementation  iron pills or injections containing iron Many iron supplementation treatments rely on diffusion  iron pills: Fat matrix releases iron into the stomach Palm fat fraction with a high melting point of around 61 °C  palm fat matrices suitable for tropical climates! D-AGRL, IFNH, Laboratory of Food Process Engineering

4. Introduction Diffusion Definition:3  mass transferprocess Diffusion coefficient D:3  causedbyconcentrationgradient Mobility of an agentmigratingthrough a certain medium  carried out byBrownianmotion  results in gradual mixingof material Mathematics:  Fick’s second law: concentration changes with time and position Fick’sfirstlaw: matter flowstowardslowerconcentration Diffusion coefficient D [m2/s] D-AGRL, IFNH, Laboratory of Food Process Engineering

5. Introduction Frame: PhD Projectaimingatdeveloping different fatcapsulesloadedwithiron in collaborationwith Human Nutrition Group  remainupto 24 hours in the human stomach  slowlyreleaseiron in a controlledfashion Central: Controlledrelease! = toset a particularagentfreewith a definedamount, at a certain timeandatspecific location4  too fast: non-transferrinboundiron infections2  tooslow: capsuleleavesstomach  lessironreleased Challenges:  howtoensurereproducibility?  howtoachievecontrolledandfullreleaseduring 24 hours? D-AGRL, IFNH, Laboratory of Food Process Engineering

6. objectives Develop a reproducible method to measure the diffusion coefficient D of iron out of palm fat Optimize the controlled release of iron out of palm fat to achieve 80 to 100 % release after 24 hours in vitro Demonstrate the technical feasibility of the project in vitro! D-AGRL, IFNH, Laboratory of Food Process Engineering

7. Methods Idea: Place palmfat-based films loaded with iron in an acidious solution to simulate the release behavior of fat capsules in the human stomach Preparation of palmfat-based films homogeneously loaded with a specified amount of iron sulfate (~ Quinbin, 2006) Carry out unsteady-state diffusivity measurements with these films to obtain the diffusion coefficient D simulating stomach conditions D-AGRL, IFNH, Laboratory of Food Process Engineering

8. methods CalculationoftheDiffusion Coefficient D:5 y slope [s-1] intercept t = independent variable (x) [s] D [m2/s] D-AGRL, IFNH, Laboratory of Food Process Engineering

9. Results Preparation of palmfat-based films Problems and Solutions Inhomogeneous crystallization  faster pouring and homogeneous surrounding temperatures Fractures and cracks  homogeneouscooling temperatures Air bubbles  slow and careful flat-rolling of the cover sheet Inhomogeneous distribution of iron  replace manual stirring with high intensity automated stirring D-AGRL, IFNH, Laboratory of Food Process Engineering

10. Results Unsteady state diffusivity measurement Problems and Solutions Down-Bending  cagestir bar in plasticdeviceto prevent spout formation (partial solution due to density difference) Up-bending  Increase volume of HCl-solution to ensure coverage in spite of up-bending D-AGRL, IFNH, Laboratory of Food Process Engineering

11. Results Conditions: 37 ˚C, 0.1 M HCl, 800 mL D-AGRL, IFNH, Laboratory of Food Process Engineering

12. Discussion Objective: Reproducibility? Achievedbyhomogeneouslyprocessingthefilms  similar treatment due to automated stirring  homogeneous distribution of iron by high intensity stirring  avoidance of damage and irregularities  reduction of pouring volume D-AGRL, IFNH, Laboratory of Food Process Engineering

13. Discussion Objective: Reproducibility? Comparison: Before: After: D-AGRL, IFNH, Laboratory of Food Process Engineering

14. Discussion Objective: Controlledandfullrelease? Almostcompletelyachievedbyincreasingironsulfatecontentto 17.2 % [w/w] reaching 90 % within 24 hours  Reduced stirring: reducedreleaseprobablydue to less homogeneous mixing of the iron within the solution  Reduction in particlesize: reducedreleaseprobably due tosmaller particles moreeasilytrapped in fatcrystalmatrix(analogousto chromatography)  Increase in FeSO4-Content: increasedreleaseprobablydue to stronger concentrationgradient D-AGRL, IFNH, Laboratory of Food Process Engineering

15. Discussion Outlook Surfactants and emulsion-matrices? Influence of different microstructures and additives? Fat-mixtures and different fatmatrices? Other possibilitiestoinfluenceandchangerelease? Optimum settings for maximum release? Possibilities forapplication:  Flavorreleasetechnology  Functionalfoodsproducts  Fight againstothermicronutrientdeficiencies D-AGRL, IFNH, Laboratory of Food Process Engineering

16. Conclusionand Summary Method with high reproducibility developed Controlled release of iron out of palm fat achieved Technical feasibilityoftheprojectdemonstrated D-AGRL, IFNH, Laboratory of Food Process Engineering

17. References 1Hurrell et al.:Particle size reduction and encapsulation affect the bioavailability of ferric pyrophosphate in rats, Journal of Nutrition, 2004 2WHO: Iron deficiency anemia: Assessment, prevention, and control, Geneva, 2005 3 Cussler: Diffusion: Mass transfer in fluid systems, 1997 4 Pothakamury and Barbosa-Cánovas: Fundamental aspects of controlled release in foods, Trends in Food Science & Technology, 1995 5 Han: Mass transfer modelling in closed systems for food packaging, particulate foods and controlled release technology, Food Science and Biotechnology, 2004 D-AGRL, IFNH, Laboratory of Food Process Engineering

18. Thank you for your attention D-AGRL, IFNH, Laboratory of Food Process Engineering