„soft‟ matters in food

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„SOFT‟ MATTERS IN FOOD Martin E. LESER Product Technology Center Marysville, OH, USA Nestle Research Center Lausanne, Switzerland p. 1 Neutrons & Food Jan 29 - Feb 1 2012

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„SOFT‟ MATTERS IN FOOD

Martin E. LESER

Product Technology Center Marysville, OH, USA

Nestle Research Center Lausanne, Switzerland

p. 1

Neutrons & Food

Jan 29 - Feb 1 2012

Agenda

• Current Consumer Trends

• R&D Challenges in Food Industry

• Conclusions, questions to be

answered

p. 2

Food Industry Transformation

Consumer Good Industry Delivering

Nutrition, Health and Wellness

3 trends shaping consumer attitudes and behaviours

Consumer Benefits meeting Trends

Pleasure Health &

well-being

Convenience

– « for me »

– Indulgence

– Premiumization

– Luxury

– Easy to handle

– On the Go

– Delivery of solutions

– Fresh & natural

– Preventive

– Personalized

Consumer Trends Demand

Food as an

Integral Delivery System

for Nutrition, Health & Wellness

6

The Value Chain in Food

The Basis for R&D on Food and Nutrition

From the farm…

…to the table

7

Fo

od

Safe

ty

Focus Change in Food Research

Raw Material

Ingredients

Preparation Processing PRODUCT

Packaging Storage

Distribution

Home Preparation

Eating

Body Effects

Product-centered / Commodity-driven

Nutrition Cost Cost Cost Cost Sensory

“Product matches expectations”

**p.o.c. = point of consumption

Consumer-centered / Benefit-driven

“Product delivers benefits”

Value Value Value Value Value Quality & Safety

Bio-inspired Processing Individualization Soft Refining **p.o.c. Production

Delight Health

Performance

Food Structure – in the center

Food Structure

Functional

Ingredients

Benefits Product

builds controls

integrates

• Evidence exists that

shows that food

structure has an

influence on digestion

dynamics and nutrient

extraction yield

Use to create

delivery systems

9

„Soft‟ Matters in Food !

Using Soft Condensed Matter physics

concepts allows Food Scientists to

significantly better understand the main

structural elements building up food

materials

10

What is ‘Soft Condensed Matter’?

– Materials which are easily deformable by external stresses,

electric or magnetic fields or thermal fluctuations

– T.A. Witten in Rev. of Modern Physics 1998

‘Soft matter occupies a middle ground between two

extremes: the fluid state and the ideal solid state. It emerges

because the thermal fuctuations that dominate the fluid state

coexist with the stringent constraints characteristic of the solid

state’.

– P.G. de Gennes in his 1991 Nobel Physics Prize speech

‘ Behaviour of ‘soft’ matter’ is dominated by one simple fact:

they contain „mesoscopic structures‟ with sizes between that

of a small molecule (H2O ~ 0.3 nm) and the beaker containing

the material’

Soft Condensed Matter – Through the

Eyes of a Food Colloid Scientist

R&D Challenges in Food Industry

p. 11 ISFRS Zürich 2009 June 15, 2009

12

Food Products are Colloidal Systems, i.e.

Soft Condensed Matter

20 mm

Oil droplet Coffee

Casein micelle in Milk Emulsion droplet in Milk Stabilized by Protein

Casein micelle network in

Yogurt

Air Bubble in Ice cream

Cubosome as is formed

during fat digestion

100 nm

13

.

Fat droplet (~ 3-5mm)

Casein micelle (~ 0.2mm)

Whey proteins (~ 0.015mm)

Lactose (~ 0.001mm)

Fat droplet membrane lipo-protein - bilayer structures

Supramolecular aggregate Peptide aggregates & Ca phosphate clusters

Protein oligomers Tetramer aggregation

Milk - A Hierarchically Designed Natural Product

Lactose molecules Increase co-solubility of

proteins

Evolution used hierachical and integrated

structures to control digestive dynamics

To digest fat droplets, the membrane has to be firstly “digested” by

phospholipases liberating not only the “fuel” but also membrane

building blocks, enzymes, bioactive peptides and nutrients.

Raw cow milk Complex bio-membrane around fat globule

Transmission Electron microscopy

Homogenized & Pasteurized Milk Transmission Electron microscopy

M.-L. Dillmann, Nestlé Research Center

p. 16

Structure evolution as function of the

lipophilicity of „oily‟ ingredients

75 nm 100 nm 50 nm 100 nm

Oil droplet Cubic Phase Vesicle Micelle

Increase hydrophilicity of lipophilic molecules

• Making oil molecules more hydrophilic and amphiphilic self-assembly structures are formed (surfactants)

• Zoo of self-assembly structures can be formed by changing nature of the hydrophilic/lipophilic balance (HLB) of surfactants

• Are these structures also formed during Digestion of oil dropletys by lipases

p. 17

Phase diagram: Oleic acid-Monoglyceride (in

PBS buffer with bile acids)

• Oleic acid and mononoglycerides

can form a variety of different

self-assembly structures

• Influence of pH is due to Oleic

acid deprotonation

• Final digestion of oil is expected

to produce a ratio 2:1 oleic acid-

monoglyceride reversed

microemulsion (EME), reversed

micellar cubic phase

(Fd3m),reversed hexagonal

phase (H2), vesicles.

SAXS Experiments

PhD S. Salentinig University of Graz, Austria

p. 18

Experimental design: Digestion of Oil

followed by Small Angle X-ray Scattering

• Online investigation of Triolein digestion using Time resolved SAXS.

• Influence of lipase, pH and bile salts on formed structures during digestion and kinetics can be measured.

or light scattering

PhD S. Salentinig University of Graz, Austria

p. 19

Self-Assembly Structures are formed inside

the Oil Droplets During Lipase Digestion

EME

EMulsion

Fd3m

Fd3m

vesicle

Salentinig Phd, Graz university

H2

– Various self-assembled structures are formed during digestion, i.e, not only vesicles and

micelles

– Self-assembly structures (i.e., interface) are formed inside oil droplets; water and

hydrophilic components (e.g. bile salts, lipase) are transported inside the oil droplets

enabling digestion of triglycerides inside the oil droplets.

PhD S. Salentinig University of Graz, Austria

Online investigation of Triolein droplet digestion using Time resolved SAXS.

Casein Micelles - Adhesive Colloids

D.J. McMahon, W.R. McManus

J. Dairy Sci. 81, 2985 (1998)

Casein micelles:

Self assembled particles

with pH-dependent charge density

but mainly sterically stabilized

Dual binding model of casein micelles D.S. Horne, Int. Dairy J. 8 (1998) 171

Hairy layer of

-casein

(extended

brush)

Acid-induced Casein Micelle Aggregation:

The yoghurt making process p

H

Ph.D P. Aichinger, Nestlé Research

Reducing

steric casein

stabilisation

Influence of Milk Processing

Heat-treatment

90°C/10min

Heat-treatment

90°C/10min

Heat-treatmentHeat-treatment

90°C/10min

Gelation conditions: 40°C, 3% GDL

0

1

2

3

4

5

0 5 10 15 20 25 30 35 40

Time [min]

G' [P

a]

Paar Physica MCR 500,

CC27, 0.1Hz, 0.04% strain

pH 4.95 pH 5.35

unheated heated

Onset of gelation

Ph.D P. Aichinger,

Nestlé Research

Interpretation:

Casein micelles are getting smaller

and more homogeneous with a

higher average density

Decrease in size

and mass

Increase in mass

Size is still decreasing

6.6 6.4 6.2 6.0 5.8 5.6 5.4 5.2 5.0 4.8

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

I(0

), R

H, R

G

pH

diluted 1+99

I(0)

RH

6

RG

Mass

size

Rg

1+99

I(0

), R

H6, R

G

pH

6.6 6.4 6.2 6.0 5.8 5.6 5.4 5.2 5.0

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

1.5

1.6

RG/R

H,q=0

I(0)

RG/R

H,

q=

0pHpH

RG/R

H,q

=0

Multi-angle 3D time resolved static and

dynamic LS

C. Moitzi

0.1

1.0

10.0

100.0

2 3 4 5 6 7

pH

d43

(mm)

Emulsion resistance to acid-induced

Precipitation

0.1%DS

No DS

1% DS

Adsorbed CN-DS complexes protect

the emulsion from acid-induced

precipitation when ≥ 1%DS

: No DS

: 0.1%DS

: 0.5%DS

: 1% DS

Mixed emulsions

Static LS

Malvern Mastersizer

Ph.D L. Jourdain

Whey Protein aggregation, Microgels

p. 25

Protein structures formed by heat-denatured whey proteins as a function of

the ionic strength and difference between the iso-electric point (IEP) of the

protein and the pH of the solution.

E.v.d. Linden, P.Venema, COCIS (2007)

Schmitt et al. Soft Matter 2010

Negative-staining TEM micrograph

from a freshly prepared 4

wt% WPM dispersion. Scale bar is

0.5 µm.

Some Concluding Remarks

Soft Condensed Matter Physics concepts

help to understand behaviour of Food Raw

Materials and their corresponding

processed end products

Future functional food colloids will be

developed in the context of Foods as an

integral delivery system

Knowing equilibrium conditions and

kinetics of structure (de-structure)

formation is essential

Using Scattering Methods will significantly

help to investigate the multi-structural

principles (on different length scales using

mixtures of different molecules)

27

Acknowledgements

M. Michel, A. Syrbe, J. B, Bezelgues, S. Serieye, L. Sagalowicz, H. J.

Watzke, M.L.- Dillmann, M. Rouvet, P. Frossard, S. Acquistapace, C.

Appolonia-Nouzille, C. Schmitt , P. Reis, L. Jourdain, H.J. Watzke, E.

Kolodziejczyk, E. Hughes, S. Acquistapace, V. Clément, C. Tedeschi, C.

Milo

• R. Miller (Max Planck Institute, Golm, Germany)

• K. Holmberg (Chalmers University, Gothenburg, Sweden)

• E. Dickinson, B. Murray (University of Leeds, UK)

• S. Salentinig, O. Glatter (University of Graz, Austria)

• C. Moitzi, A, Stradner P. Schurtenberger et al. (University of Fribourg,

CH)

28

What to do now with my new inventions?