1. Cereal Bars Containing SAEF®, a Novel Superhydrating
Fiber, Exhibit Significantly Greater Satiety-Enhancing
Properties than Cereal Bars Containing Glucomannan
in Simulated Stomach Model
Hassan M. Heshmati1, MD; Eyal S. Ron1, PhD; Christian Demitri1, PhD; Yishai Zohar1; Alessandro
Sannino2, PhD; Tim T. Lambers3, PhD; Ann C. Stijnman3; Hock S. Tan4, PhD.
1Gelesis, Inc., Boston, MA, USA; 2University of Salento, Lecce, Italy; 3NIZO food research BV,
Ede, Netherlands; 4Bionex Pharmaceuticals LLC, North Brunswick, NJ, USA.
1
I N T R O D U C T I O N
Overweight and obesity are becoming major health
problems worldwide (1).
The therapeutic benefit of all currently available
anti-obesity tools is limited by their marginal ef-ficacy
and variable tolerability and safety profiles.
Interventions which act mechanically by occupy-ing
stomach volume, extending gastric emptying time,
and increasing the elastic response and vis-cosity
of the upper gastrointestinal content, could
potentially be very beneficial.
Dietary fibers have been used for weight manage-ment
because they possess a number of the prop-erties
required to induce satiety (2). In particular,
clinical trials have demonstrated that glucoman-nan
causes weight loss (3) and in 2010, the Euro-pean
Food Safety Authority (EFSA) gave a positive
scientific opinion, granting glucomannan claims
for weight management (4). However, in higher
amounts dietary fibers have undesirable gastroin-testinal
side effects.
SAEF® (Satiating Advanced Edible Fiber), a novel
hydrogel, is capable of absorbing water up to 100
times its original weight in the stomach and the small
intestine environment. SAEF® also increases the
elasticity and viscosity of the contents of the small
intestine prior to being degraded in the large intes-tine
where it releases the absorbed water (Figure 1).
O B J E C T I V E
The aim of this study was to assess the character-istics
of cereal bars enhanced with SAEF® in com-parison
to glucomannan or control cereal bars in
order to evaluate their potential effect on satiety.
M A T E R I A L S
Cereal bars containing either 5% SAEF®, 5% gluco-mannan,
or no addition (control) were studied.
M E T H O D S
The NIZO in vitro simulation of physiological diges-tion
(SIMPHYD) model was used to measure the
textural properties of food ingredients under gas-trointestinal
conditions. The model consists of a
glass vessel that has the same size and shape as a
typical human stomach, with the same rate of mix-ing.
First, 50 mL of gastric fluid (pH 1.5), 250 mL of
water, and 50 g of masticated cereal bars (chewed
by human volunteers for 20 sec) are added to the
chamber. Next, 200 mL of gastric fluid (pH 7) is
added so that a total volume of 500 mL required for
optimal functioning of the model is achieved. This
step is followed by acidification using HCl. The rate
of acidification allows the media to reach a pH of 2
after approximately 50 min which is a typical stom-ach
acidification rate following breakfast (5). Imme-diately
after addition of the gastric fluid, in-line force
measurements with the recording of force profiles
for a total of 2 h are started. The average value of
independent experiments, performed in triplicate, is
reported for each cereal bar.
In addition to SIMPHYD model, a Rheometrics Me-chanical
Spectrometer RS-800 was used for the
determination of the rheological properties (elastic
modulus and viscosity) of a second similar set of
digested cereal bars.
R E S U L T S
SAEF® gel-like particles remained intact even af-ter
2 h of simulated gastric digestion and clearly
formed a larger volume. The glucomannan fibers

2. Figure 1. Overview of SAEF® concept
2
SAEF® is
ingested orally
before or
between meals.
Step 1.
After swallow-ing
SAEF®, the
subject drinks
water.
Step 2.
SAEF® particles
absorb water in
the stomach.
Step 3.
SAEF® particles
mix with food
and create a
larger volume.
Step 4.
SAEF® particles
delay gastric
emptying and
then shrink as
the pH of the
stomach de-creases
during
digestion.
Step 5.
SAEF® particles
absorb water in
the small intes-tine,
increasing
viscosity.
Step 6.
The passage
of sugars and
fatty acids
into the blood-stream
is
delayed.
Step 7.
SAEF® par-ticles
degrade
in the colon,
releasing the
absorbed water
and passing
through the
system.
Step 8.

3. Figure 3.
Figure 5. Figure 6.
3
Figure 2.
Appearance of control cereal
bars after 2 h of simulated gas-tric
digestion.
Appearance of glucomannan-enhanced
cereal bars after 2 h
of simulated gastric digestion.
Figure 4.
Appearance of SAEF®-enhanced
cereal bars after 2 h of simulat-ed
gastric digestion.
Force profile of control cereal bars during simulat-ed
gastric digestion.
Force profile of glucomannan-enhanced cereal
bars during simulated gastric digestion.
Figure 7.
Force profile of SAEF®-enhanced cereal bars dur-ing
simulated gastric digestion.
Table 1.
Control
Glucomannan
SAEF®
Rheological measurements of 3 different digested
cereal bars.

4. 4
formed aggregates and remained at the bottom of
the simulated stomach in contrast to SAEF® par-ticles
which did not form aggregates and were dis-persed
homogenously (Figures 2, 3, 4). Maximum
forces observed inside the SIMPHYD stomach
model with SAEF® cereal bars were up to 8 times
larger than those observed with glucomannan or
control cereal bars. Differences started at 7–10
min onwards and lasted up to 2 h with a maximum
at 17–33 min (Figures 5, 6, 7).
SAEF®-enhanced cereal bars also displayed sig-nificantly
higher elastic modulus and viscosity than
glucomannan-enhanced cereal bars in the Rheo-metrics
Mechanical Spectrometer (Table 1).
These results are consistent with previously report-ed
data, showing the superior rheological properties
of neat SAEF® compared to other fibers, including
glucomannan (6).
C O N C L U S I O N
Cereal bars containing SAEF® have better textural
properties and significantly greater elasticity and
viscosity after digestion than the other tested ce-real
bars. These two properties are known to en-hance
satiety.
Through its advanced properties, SAEF® could be a
promising new approach for weight management by
inducing prolonged satiety.
R E F E R E N C E S
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syndrome and relationship to gastroin-testinal
functions. Gastroenterology, 2010,
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3. Sood N, Baker WL, Coleman CI. Effect of glu-comannan
on plasma lipid and glucose con-centrations,
body weight, and blood pressure:
systematic review and meta-analysis. Am J
Clin Nutr, 2008, 88, 1167–1175.
4. Agostoni CV. EFSA Journal, 2010, 8, 1798.
5. Simonian HP, Vo L, Doma S, Fisher RS, Park-man
HP. Regional postprandial differences in
pH within the stomach and gastroesophageal
junction. Dig Dis Sci, 2005, 50, 2276–2285.
6. Demitri C, Marotta F, Sannino A, Ron ES, Zo-har
Y, Ambrosio L. Rheological and mechani-cal
comparison between dietary fibers and a
novel superabsorbent biodegradable hydrogel
(SAEF®). In: Program of the 24th Annual Con-ference
of the European Society for Biomate-rials,
September 4–8, 2011; Dublin, Ireland.
Abstract #643.
The content of this document was presented in a Poster at Obesity 2011,
29th Annual Scientific Meeting, Orlando, Florida, October 1–5, 2011.