Gva cost lunteren 2012 v3
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Transcript of Gva cost lunteren 2012 v3
Together to the next level
Emulsion structure
in relation to
sensory and and
digestive
functionality George van Aken [email protected]
Jennifer Aniston (W Magazine photo shoot)
OPTIMAL FAT FORMULATION IN WEIGHT
MANAGEMENT PRODUCTS?
HOW CAN WE DESIGN EMULSIONS TO AVOID
OVEREATING?
FOCUS
COMBAT METABOLIC SYNDROME
Positive energy balance
Heilbron et al, Int. J. Obesity, (2004)
Ectopic fat storageliver, heart, pancreas.
skeletal muscle,abdominen
METABOLIC SYNDROME:
Obesity, CardioVascular Disease
inflammation, diabetes type II,
high blood pressure, atherosclerosis
Enlarged adipocytes:• Impared adiposite
differentiation and function
• Modulated endocrine
function
Fat storage exceeds
the normal storage
capacity of adipositesHigh blood triglycerides
Impaired glucose homeostasis
Approaches against metabolic
syndrome
• Reduce ectopic fat • Reduce caloric intake
• Increase satiety
• Sport
• Burn more fat, built more muscles
• Improved clearance of inflammatory pro-atherogenic blood lipoprotein remnants
• Increase in Omega-3 and short and medium chain fatty acid, Increase fibers. Reduce sugar. Increase fibers.
• Reduce saturated (palmitic) fatty acids (Challenged)
• Lower blood pressure, less vessel injury leading to better cardiovascular health
• Low salt, less stress
• Low glycemic index• Low sugar, slow starch, slower gastric emptying, slower absorption
Approaches against metabolic
syndrome
• Reduce ectopic fat • Reduce caloric intake
• Increase satiety
• Sport
• Burn more fat, built more muscles
• Improved clearance of inflammatory pro-atherogenic blood lipoprotein remnants
• Increase in Omega-3 and short and medium chain fatty acid, Increase fibers. Reduce sugar. Increase fibers.
• Reduce saturated (palmitic) fatty acids (Challenged)
• Lower blood pressure, less vessel injury leading to better cardiovascular health
• Low salt, less stress
• Low glycemic index• Low sugar, slow starch, slower gastric emptying, slower absorption
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Product requirements
• Should reduce caloric intake• Early satiety
• Long lasting hunger reduction
• Should be healthy• Low glycemic index
• Reduce blood triglycerides, improve inflammatory
response
• Should be preferred by consumer• Sensory quality
• Creamy, full taste and aroma
6
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Goals:
• Healthy: low calorie intake at satiety
• Sensorially liked: creamy, smooth, full
2 finalized projects at TIFN:
- Improved satiety by emulsified fat
- Improved creaminess by emulsified fat
7
Application
Contract research
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Main findings of the two
projects
• Sensory perception of emulsions determined
by the behaviour during oral processing
• Satiety by emulsions influenced by the
structure and dynamics in the gastro-intestinal tract
Needed is a better understanding and control of
the interactions of the emulsions with the
human body product formulation
8
ORAL BEHAVIOUR OF
EMULSIONS
Sensory pereption
9
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TIFN Project team:
Diane Dresselhuis
Erika Silletti
Guido Sala
Els de Hoog
Monique Vingerhoeds
Jan Benjamins
Franklin Zoet
Jerry van Maanen
Eefjan Timmerman
Willem Norde
Martien Cohen Stuart
George van Aken
Unilever
DSM
Cosun
Avebe
FrieslandCampina
NIZO food research
TNO
WUR
Product developers approach
Product development:composition, structure • reduced fat
• thickeners
• particles
• aroma’s
• sugar replacers
Product characteristics:sensory properties
• not so creamy, thin, slimy, gritty
• off tastes, off flavours, unbalanced flavours
Sensory paneling
correlations
Instrumental measurements:• viscosity, gel strength, fracture behavior
• friction measurement
• droplet and particle size
• aroma and flavour release
Correlations
are often
poor
10Together to the next level
After taste oral and
pharyngeal coating,
flavour release
Masticatoryoral processing
many structural changes,
flavour release
Sensory perception of food
First bite rheology, temperature
Gut signalsSatiety, well being
Brain
Receptors
Appearancecolor, shine,
structure, flow, aroma
swallow
Feed back
11Together to the next level
Tribological regimes of papillae
(Stribeck curve)
Static friction
speed
viscosity
Friction force
hydrodynamic
boundary
mixed
Only viscous
forces
Static surface bonds
Transient surface bonds and
corrugations
Liquid starts to
interpenetrate
palate
papilla Gap-width
increases with
speed viscosity
Hydrodynamic modelling
of the soft deformable
papilla surface*
* Van Aken, G.A., Modelling texture perception by soft epithelial surfaces, Soft Matter, 2010, 6, 826–834
“Rough
tongue”
astringency
“Smooth” thickness
particle size
Emulsions:
Large structural changes, even for thin liquid emulsions:
THIS is what you taste!
13Together to the next level
TI food and
Nutrition
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Saliva-induced
droplet aggregationFormation of slimy
structures
Fat spreading at air
bubble surfaces
Droplet coalescence
Release of
emulsions droplets
Droplet-coating of
oral surfaces
Amylase induced
starch breakdown
Structural changes in the oral cavityFood emulsions
Inhomogeneous coverage
of tongue papillae
Van Aken et al., Food Colloids, Dickinson ed., RSC, 2005, pp.356 – 366;
Curr. Opin. Colloid Interface Sci. 2007, 12, 251-262. .
Fracture of gels into
‘crumbs’
Droplet spreading at
tongue surface
14
TI food and
Nutrition
Saliva-induced flocculation1:1 mixtures of emulsions with saliva
Emulsion -potential (mV)
0
10
20
30
40
50
-100 -50 0 50 100
d 32
emulsion
mixture
E. Silletti et al., Food Hydrocolloids 21 (2007) 596–606; J.Colloid Interface Sci. 313 (2007) 485–493
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Viscosity increases due to saliva-induced droplet
aggregation → increased creaminess
Saliva-induced
droplet
aggregation
Liquid emulsion
ξ < 0 ξ > 0
Vingerhoeds et al. Food Hydrocolloids, 23(3) (2009), 773-785.
Van Aken et al., Curr. Opin. Colloid Interface Sci. 12 (2007), 251-262. 16
at 100 s-1
TI food and
Nutrition
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Interaction with the tonguePhD study of Diane Dresselhuis
Visualization of fat
retention on pig tongue
CSLM image
500 500 m
10 wt% SF oil; 1 wt% WPI
red: oil; green: tongue papillae
Dresselhuis et al., Journal of Colloid and Interface Science (2008)
17
TI food and
Nutrition
Fat retention on the tongue
Fat adhesion and retention larger for more unstable emulsions
→ increased creaminess
emulsions varying in stability to coalescence
o/w emulsion
7% SF (sunflower oil)
stabilized with protein WPI
stable unstable
WPI 1 0.3
[%]
D[3,2] 0.92 1.15
[ m]
1.6 1.4
(@51 s-1)
[mPa s]
gra
m f
at
rem
ain
ing in m
outh
0 .0
0 .1
0 .2
0 .3
1% W P I S F 0.3 wt% W P I S F 1% W P I S F L
gra
m f
at
rem
ain
ing
in
mo
uth
spit
rinse
0.0
0.1
0.2
0 .0
0 .1
0 .2
0 .3
1% W P I S F 0.3 wt% W P I S F 1% W P I S F L
gra
m f
at
rem
ain
ing
in
mo
uth
spit
rinse
Fat
remaining
after first
spit
Fat
remaining
after water
rinsing
unstablestable
Dresselhuis et al., Journal of Colloid and Interface Science (2008)
18Together to the next level
TI food and
Nutrition
Friction between PDMS (hydrophobic) and glass (boundary friction regime)
Fat reduces the friction (→ increases creaminess), but an increase
in fat content has no further effect
0.0
0.2
0.4
0 10 20 30 40Fat content (wt%)
Friction c
oeffic
ient
unstable emulsionstable emulsion
0.6
Fat content (wt%)
0.3 wt%WPI
1.0 wt%WPI
Effect of adsorption of fat
onto the surface
Dresselhuis et al. Food Biophysics (2007)
Dewetting of saliva
from the oral surfaces
19Together to the next level
TI food and
Nutrition
LUBRICATING
FATTY COATING
rubbing,
shear
EXTENDED
aroma release
Liquid
emulsion
shear
saliva
HIGHER VISCOSITY by saliva
–induced droplet flocculation
Droplet coating
on oral surfaces
saliva
VISCOUS
BOLUS of
gel particles
and saliva
ACTIVE
INACTIVE
Gelled
emulsion
saliva
saliva
GEL FRACTURING dependent on gelling
agent and droplet interaction
Creamy
Thick
Rich
Smooth
Coating
What makes emulsions creamy?
20Together to the next level
26 refereed journal publications and 8 book chapters (2005-2011) by the TIFN project team
porous
TI food and
Nutrition
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Restored creaminess in
reduced fat products• Restore boundary lubrication:
• Emulsion sensitized to coalescence (increase solid fat content, adjusted emulsifier mix, OSA starch)
• Specific lubricating emulsifiers
• Reduce acidity and astringency (polyphenols)
• Restore viscosity:• Smaller droplet size
• Similar thinning behavior during oral processing
• Thickeners, compatible with saliva (polysaccharides,
resistant starch)
• Small particles (size below detection limit)
• Restore flavour:• Flavor rebalancing
• Controlled release
21
GASTRO-INTESTINAL
BEHAVIOUR OF EMULSIONS
Digestion
22
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TIFN project team:
Raymond Schipper
Anne Helbig
Man Minekus
Lex Oosterveld
Erika Silletti
Esther Bomhof,
George van Aken
Unilever
DSM
CSM
VION
FrieslandCampina
NIZO food research
TNO
WUR
B-1007: Engineered sensory and dietary functionality of dispersed fat
Engineered sensory and dietary
functionality of dispersed fat
Develop fundamental knowledge on the oro-gastro-intestinal behaviour of
food emulsion systems and how this behaviour relates to physiological responses
Structural
componentAdsorbed layer
Fat type
Droplet size
Continuous phase
Behaviour in oral-
gastro-intestinal
tract
Physiological
responses
Physiology
Oral/Gut BiochemistryPhysical chemistry
B-1007: Engineered sensory and satiating functionality of dispersed fat
Artifical mouth
BellyQuintet
pH STAT
Artificial
digestion model
TinyTIM
Pig Model
Human Studies
In vitro gastric
and intestinal
models
Animal Model
Human
subjects
In vitro,
in vivo
mouth
model
Tongue
cup
MRI
of stomach
Line up of experimental models with
increasing complexity
In silico
modeling
FUNDAMENTALS OF FAT
DIGESTION AND ABSORPTION
25
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What is the problem with fat
digestion?
Triglycerides are insoluble in water and therefore
cannot be detected and absorbed directly
• Lipases are water soluble and can only be active at
the oil/water interface → efficient lipolysis requires
large O/W interfacial areas (small droplet sizes)
• Adsorbed layer of emulsifiers and lipolytic products (fatty acids, monoglycerides) may hinder lipase activity
• For saturated C12 and longer, the lipolytic products
(fatty acids, monoglycerides and diglycerides) are
insoluble solids
• Unsaturated long chain monoglycerides (e.g. C18:1)
form cubic liquid crystals
Role of bile in the small intestine
• Bile removes emulsifiers from the interface
• Pancreatic lipase hydrolyses triglycerides into
fatty acids and sn-2 monoglycerides by lipases
• For saturated C12 and longer, the formed fatty
acids, monoglycerides and diglycerides are insoluble solids
• Unsaturated long chain monoglycerides (e.g.
C18:1) form cubic liquid crystals
Bile
micelle
Bile solubizes the
insoluble lipolytic
products into micelles
pancreatic lipase
carboxyl ester lipase
Fat digestion: main enzymatic processes
28Together to the next level
Stomach
Small
intestine
Gastric lipase
(<10%)
Pancreatic lipase
(almost complete)
Bile micelles
Portal
vein to
liver
Small intestinal
wall
lymph
chylomicron
Serum
albumin
transporter
Effect of the lymphatic route
• Long chain MUFA, SAFA and
vitamins bypass the liver
• Primarily used by the body for
energy (muscles) and stored in
adipose tissue
liver
Routing of fatty acids - overview
C11:0 and shorter
C12:0 and longer
Oleic acid
ω-6 PUFA
ω-3 PUFA
Portal vein
Lymph vessel
Main
blood
stream
ω-3 DHA
VLDL
glucose
FA
glucose
chylomicrons
serum
albumin
Nerve membrane
Muscles Adiposites
LDL
Energy
supply
Functional
lipids
Conjugated
double bonds:
CLA
Regulated stomach emptying
of nutritious liquids:Roughly constant nutrient release to the small intestine
intake
bile pancreas
Stomach
activity
duodenum jejunum ileum
Stomach
emptying
absorptive cellsPylorus
area concentration absorbable nutrients
I-cells detect nutrients(mainly duodenum, jejunum)
++--
Regulated gastric emptying at 1-2 kcal/min• Corresponds to 1440 - 2880 kcal/day, similar to the advised daily caloric intake
Regulated small intestinal
residence time (ileal brake)
intake Pylorus
bile pancreas
duodenum jejunum
L-cells detect nutrients (ileum and COLON)
Transit speedStomach
Absorptive cells
-
Ileum
• Compensates for a high caloric entry into the intestine or slow
enzymatic hydrolysis
• Normal condition: nutrients reach ileum but not colon
33
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Computer
modelingFed by: physiological literature
in vitro studies
(in vitro gastric, Simfyd, tiny TIM)
Gastric
volume
Fullness
In-silico model
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Intake(water,
protein,fat,
carbohydrate
as a function
of time)
Fundus
Corpus
Antrum Duodenum Jejunum 1
Jejunum 2
Jejunum 3 Ileum 1
Ileum 2
Ileum 5
Ileum 6 Colon
Ileum 3
Ileum 4
FFAFFA
FFA
FFA
FFA
FFA
FFA
FFA
FFA
FFA
Total
absorbable
nutrients
pylorus
Nutrient
density in
chyme
Hunger
absorption
I-cellsCCK
oxymodulin
• Potentiate glucose-stimulated insulin
secretion
• Reduce glucagon
avoid high blood sugar
oxymodulin
Insufficient calories
in my gut...
I should eat!
L-cellsPYY, GLP1,
oxymodulin
Enough calories in my stomach ... time to stop eating!
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Examples
1. Emulsions that cream in the stomach
2. Emulsions that sediment in the stomach
35
Increase fullness during eating by improving
the emulsion stability in the stomach
Bulk fat and many emulsions and are unstable in the stomach
(low pH, enzymes) and separate a fat–rich creamed layer .
Consequence: an energy poor lower phase empties fast, quickly
reducing the volume of the stomach
Effect gastric instability of an emulsion
*Marciani et al., British Journal of Nutrition
(2009), 101, 919–928
Simulation of an emulsion of 40 g
fat and 200 g water; effect of fat
floating as a creamed layer
0
1
2
3
4
5
6
7
8
0 200 400 600 800
a.u
.
time (min)
Fullness
reference
fully creamed fat layer
0
2
4
6
8
10
12
0 200 400 600 800
a.u
.
time (min)
Hunger
reference
fully creamed fat layer
• Expected to improve satiety during and shortly after the meal,
reducing meal size.
Approach: induce sedimentation in stomach
Collaboration with Alan Mackie (IFR) for in vivo testing
5 % triolein, 1 % WPI,
1 % caseinate
Full fat milk
Simulation of an emulsion of
40 g fat and 200 g water;
effect of fat sedimentation,
leading to an initial emptying of
a 25 % fat emulsion
Van Aken et al., Food Hydrocolloids (2011)
-1
0
1
2
3
4
5
6
7
8
9
0 200 400 600 800
a.u
.
time (min)
Fullness
reference
sedimented fat layer
-2
0
2
4
6
8
10
12
0 200 400 600 800
a.u
.
time (min)
Hunger
reference
sedimented fat layer
Relevance: suggestions from
experiments and simulation
Thin liquid high-calori drinks:
• Tend to be over-consumed because of quick emptying
before regulated emptying is activated. (less fullness during
the meal)
• The initially fast-emptying nutrients are quickly absorbed, do
not contribute to longer term hunger reduction.
(Semi-)solid high-calori food:
• Is emptied slowly, regulated by caloric content and slowed
down further by gastric “erosion” of food lumps
• Physiological estimation of calories in reserve in the
stomach and small intestine is more accurate.
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Challenge
• Combine the concepts and techniques
developed for sensory perception, digestion
and satiety of food emulsions to construct
highly liked food emulsions that are more
satiating
• Solutions highly dependent on product type
39
Thank you!
41Together to the next level
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Creating the future together