van aken euro fed lipids final

Monday, September 26, 2011

Together to the next level

How fat composition

and food formulation

affect absorption and

mediate food intake Which way to go? George van Aken

[email protected]

Key question

Fat is highly caloric, sensorially pleasant food

constituent which entices overeating

How can we avoid overeating?

2 Together to the next level

Origin of the study

Finalized project at TIFN:

Engineered Sensory and Dietary Functionality of Dispersed

Fat

• Project goals:

• Optimization of fat-related sensory and dietary effects.

• Main focus on satiety and food intake reduction.

• Key objectives:

• Gastro-intestinal behaviour of food emulsions in relation to physiological

responses.

• Physical-chemical and biochemical mechanisms behind this behaviour.

• Engineering rules to help control the processing, delivery and release of fat

in the digestive tract.

NOW focussing on application at NIZO food research

• ,


Outline

• Fundamentals of fat digestion and absorption

• Role of fat consumption in obesity

• How can we reduce caloric intake?

• Conclusions


FUNDAMENTALS OF FAT

DIGESTION AND ABSORPTION


Emulsion digestion and absorption

lipases bile

Fatty acid

absorption

Regulation of

digestion and food

intake

Digestion

processes

Delivery of

-3, -6 and vitamins

blood

Fat digestion: main enzymatic processes


Stomach

Small

intestine

Gastric lipase

(<10%)

Pancreatic lipase

(almost complete)

Small intestinal

wall

Fast

Slow

lymph

chylomicron

Serum

albumin

transporter

Short chain and

polunsaturated FFA

LCFA

http://upload.wikimedia.org/wikipedia/commons/6/6c/ALB_structure.png

liver

Routing of fatty acids - overview

C11:0 and shorter

C12:0 and longer

Oleic acid

ω-6

ω-3

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

http://upload.wikimedia.org/wikipedia/commons/6/6c/ALB_structure.png

ROLE OF FAT CONSUMPTION

IN OBESITY


http://en.wikipedia.org/wiki/File:Obesity6.JPG

Positive energy balance

Heilbron et al, Int. J. Obesity, (2004)

Ectopic fat storage in:

• liver

• heart

• pancreatic β-cells

• skeletal muscle,

• abdominal fat

METABOLIC SYNDROME:

Type II diabetes, OBESITY,

Inflammatory reactions, high

blood pressure,

atherosclerosis, CVD

Enlarged adipocytes:

• Impared adiposite

differentiation and

function

• Modulated

endocrine fuction

Fat storage exceeds

the normal storage

capacity of adiposites


Ease of overeating of fat

Nutrient Caloric

value

(kcal/g)

Sensory effect Ease of

overeating

Proteins 4 Can be relatively unpleasant :

tends to a highly viscous, tough and dry

mouthfeel

small

Sugars 4 Pleasant :

viscous mouthfeel

sweet

moderate

Fats 9 Pleasant:

thin mouthfeel, lubricant, smoothening

adds to flavour richness

high

BUT: the body is designed for efficient

absorption and to control food intake

Small intestine

pancreas

Stomach

duodenum jejunum ileum

Stomach

emptying

absorptive cells Pylorus

intake

gall

bladder

Feedback

COLON

Detailed in vivo human study to confirm these feedback mechanisms are

still ongoing at TIFN in collaboration with Maastricht University

Nutrient transport through the

gastrointestinal tract is regulated

Physiological restrictions: • Vmax per unit length of small intestine

• Absorption requires transfer from polymers to monomers: • proteins amino acids

• di-, oligo-, polysaccharides monosaccharides

• triglycerides fatty acids, monoglycerides

Regulation mechanism for efficient absorption: • Efficient and gradual absorption of nutrients by small intestine

• > 95 % for a single shot of 650 g oil (220% of advised total daily caloric intake)

• Small intestinal transit time adjusted to avoid spill over into the colon

Regulation mechanisms for food intake: • Feeling of a full stomach

• related to gastric distension + the detection of nutrients in the small intestine

• Feeling of hunger • related to a low reserve of nutrient in small intestine

- GLP-1

Some main feedback mechanisms

Pylorus

duodenum jejunum ileum

L-cells

Transit speed max

storage

bile pancreas

I-cells

intake

-

CCK

-

Full stomach

Meal

ending

-

PYY,

GLP-1 No

hunger

CCK +

+

Large reservoir of nutrient

present in small intestine

CCK-B

Next

meal

Computer

modelling Fed by: physiological literature

in vitro studies

(Belly Quintet, Symphid, TIM)

Van Aken, Food Biophysics (2010) 5(4):258–283

HOW CAN WE REDUCE THE

CALORIC INTAKE?


1. Increase feeling of a full stomach during

eating by reducing the initial fast emptying

• Gastric emptying of non-nutritional liquid is fast and

dependent on the viscosity

• Gastric emptying of nutritious liquids is much slower and

regulated at a constant release of energy (~ 2 kcal/min)

• Regulation only starts after sufficient nutrients have

entered the small intestine. This may take several minutes.

• Fullness is however dependent on both gastric distension

(increased) and nutrient detection in the small intestine

(lowered)

Simulation of an

emulsion of 30 g fat

and 200 g water;

effect of a 1000x

increase in viscosity

2. Keep a full stomach during eating by

control of emulsion stability

• Gastric emptying of nutritious liquids regulated at a

constant release of energy (~ 2 kcal/min)

• Bulk fat and many emulsions and are unstable in the

stomach (low pH, enzymes) and phase separate into

an energy- rich creamed layer (containing the fat)

and an energy-poor lower phase *

• Consequence: the energy poor lower phase empties fast, quickly reducing the volume of the stomach

• Felt as less fullness during and shortly after the meal.

*Marciani et al., British Journal of Nutrition (2009), 101, 919–928

Marciani et al. 2009 *

Simulation of an emulsion of 30 g

fat and 200 g water; effect of fat

floating until fundus and corpus

have emptied (50 ml water)

Approach: inverted phase separation in

stomach

A number of sedimenting emulsion systems

have been identified*

CURRENTLY investigated in an in vivo human trial

(TIFN, IFR, (2) Norfolk and Norwich University hospitals NNUH)

Expectation: Gastric volume reduces slowly → more fullness

during a meal → sooner meal ending

5 % triolein, 1 % WPI,

1 % caseinate

Full fat milk

Simulation of an emulsion of

30 g fat and 200 g water;

effect of fat sedimentation until

5 ml of fat is left in the antrum

* Van Aken, G.A., Bomhof, E., Zoet, F.D., Verbeek, M., Oosterveld, A., Food Hydrocolloids (2011), 25: 781-788,

Differences in in vitro gastric behaviour between homogenized milk and emulsions stabilised by Tween 80, whey protein, or whey protein

and caseinate

3. Control the rate of intestinal fat hydrolysis

Small intestinal transit time normally regulated to compensate for

a high caloric entry into the intestine or slow enzymatic hydrolysis

(“Ileal brake”)

Sugars delivered to the ileum or fat delivered to the jejunum shortly (e.g.

15 min) before a meal reduces food intake from that meal.

Compensates only; no effect on total caloric intake.

Simulation of an


and 200 g water;

effect of a 10x

slower digestion

4. Reduce the rate of intestinal

absorption of fat hydrolysis products

• Oleic acid or oleic acid + monoolein intubated into the jejunum gives a

strong hunger suppressing signal (Little et al., Am. J. Physiol.2005)

• A similarly strong effect is also found for 1,3 diglycerides

(Kristensen et al., J. Nutrition 2006; Yanai et al., Nutrition Journal, 2007)

• Stronger effect of predigested TG, oleic acid and 1,3-diglycerides also

reduces total caloric intake (overcompensation).

The excess suppression by oleic acid seems only to occur beyond a

higher level of free oleic acid intubated

(Woltman & Reidelberger, Am. J. Physiol. 1995).

ENTEROCYTE

ENTEROCYTE

Possible explanation of stronger effect of

predigested TG, oleic acid and 1,3-diglycerides

Fatty acid

receptor

glycerol-3-phosphate

pathway

SLOW

Pancreatic

lipase

absorption

monoglyceride

pathway

FAST

Pancreatic

lipase

absorption

Fullness Food intake

reduction

chylomicron

Kristensen et al., J. Nutrition 2006

Portal

vein

Lymph

vessel

Simulated effect of slower intestinal

absorption

Simulation of an


and 200 g water;

effect of a 4x

slower absorption

Most effective fat-based way to reduce hunger and

food intake?

Replace TG by fatty acids, diglycerides,

monoglycerides, non-glyceride esters

CONCLUSIONS


summary

Fat is highly caloric, sensorially pleasant food

constituent which entices overeating

How can we avoid overeating?

Lipids are also satiating and can be used to limit food intake, but it needs to be in an

appropriate form or type

Opportunities for product development!


Optimized formulations of fat/lipids in food may help to

• Reduce the over-eating during a liquid meal: • Avoid fat creaming in the stomach (acid and pepsin stable

emulsifiers) (ongoing in vivo human study)

• Induce gastric sedimentation of fat (dense fat structures)

(ongoing in vivo human study)

• Decrease hunger and suppress intake on next meal: • Increase the viscosity (however less fullness during the 1st meal)

• Marginal effect of slower digestion (emulsifiers that slow release

of FA)

• Large effect by slower absorption: • Replace TG by fatty acids, diglycerides,monoglycerides, non-

glyceride esters

• Release system of encapsulated fatty acids, diglycerides, non-

glyceride esters fatty acids


Tiny TIM

:

Let’s translate:

Opportunities for product development


Computer

modelling

SYMPHID Human

subjects

Animal Model

Belly Quintet

Food grade

pilot plant

27 Technology for your success

Together to the next level

Creating the future together

van aken euro fed lipids final

Documents

optimization of fat

release of fat

fat composition

vitamins blood fat digestion

ectopic fat storage

key question fat

mediate food intake

food intake reduction