Combined heterogeneous distribution of salt and aroma in food enhances salt perception

Abstract

Aroma-taste interactions and heterogeneous spatial distribution of tastants were used as strategies for taste enhancement. This study investigated the combination of these two strategies through the effect of heterogeneous salt and aroma distribution on saltiness enhancement and consumer liking for hot snacks. Four-layer cream-based products were designed with the same total amount of sodium and ham aroma but varied in their spatial distribution. Unflavoured products containing the same amount of salt and 35% more salt were used as references. A consumer panel (n=82) rated the intensity of salty, sweet, sour, bitter and umami tastes as well as ham and cheese aroma intensity for each product. The consumers also rated their liking for the products in a dedicated sensory session. The results showed that adding salt-associated aroma (ham) led to enhancement of salty taste perception regardless of the spatial distribution of salt and aroma. Moreover, products with a higher heterogeneity of salt distribution were perceived as saltier (p<0.01), whereas heterogeneity of ham aroma distribution had only a marginal effect on both aroma and salty taste perception. Furthermore, heterogeneous products were as well liked by consumers compared to the homogeneous products.

Full text

Food &
Function
PAPER
Cite this: DOI: 10.1039/c4fo01067a
Received 21st November 2014,
Accepted 14th March 2015
DOI: 10.1039/c4fo01067a
www.rsc.org/foodfunction
Combined heterogeneous distribution of salt and
aroma in food enhances salt perception
Marion Emorine,
a,b,c
Chantal Septier,
a,b,c
Isabelle Andriot,
a,b,c
Christophe Martin,
a,b,c
Christian Salles*
a,b,c
and Thierry Thomas-Danguin
a,b,c
Aroma–taste interactions and heterogeneous spatial distribution of tastants were used as strategies for
taste enhancement. This study investigated the combination of these two strategies through the effect of
heterogeneous salt and aroma distribution on saltiness enhancement and consumer liking for hot snacks.
Four-layered cream-based products were designed with the same total amount of sodium and ham
aroma but varied in their spatial distribution. Unflavoured products containing the same amount of salt
and 35% more salt were used as references. A consumer panel (n= 82) rated the intensity of salty, sweet,
sour, bitter and umami tastes as well as ham and cheese aroma intensity for each product. The consu-
mers also rated their liking for the products in a dedicated sensory session. The results showed that
adding salt-associated aroma (ham) led to enhancement of salty taste perception regardless of the spatial
distribution of salt and aroma. Moreover, products with a higher heterogeneity of salt distribution were
perceived as saltier (p< 0.01), whereas heterogeneity of ham aroma distribution had only a marginal
effect on both aroma and salty taste perception. Furthermore, heterogeneous products were well liked by
consumers compared to the homogeneous products.
Introduction
High dietary salt (NaCl) intake is recognised as an important
causal factor in elevated blood pressure, the leading risk for
premature death in the developed and developing world.
1,2
Moreover, a high dietary salt intake is associated with several
health issues, including stroke, cardiovascular events, gastric
cancer, kidney disease and, indirectly, obesity.
3
Health
agencies throughout the world recommend a drastic reduction
in salt intake,
4–6
and actions with this aim have been pro-
moted in many countries.
7
However, salt is a multifunctional
component in food. It performs many functions that can be
interrelated and interdependent
8
such as preservation,
9
water-
binding, and texture processing.
10
In addition, reduction of
salt in food products changes the sensory properties of pro-
cessed food. Salt is not only a stimulus that elicits the percep-
tion of saltiness, but it also influences the overall flavour
perception.
11
A reduction in salt may influence the temporal
release of volatiles, which has been shown to be dependent
not only on the salt concentration but also on the hydrophobi-
city of the volatile compounds.
12
In many cases, lowering salt
content in foods is associated with a loss of liking and a
decrease in consumers’acceptance of the product.
13–15
More-
over, food flavour characteristics are very important in the
decision to purchase or repurchase a food.
16
Thus, the
reduction of salt content in processed food without loss of
consumer acceptability has become one of the major issues
for food manufacturers.
17,18
Among the strategies investigated to compensate for salt
reduction in food
19
is the manipulation of the delivery of taste
stimuli to enhance taste perception.
20
Indeed, as reported for
sweetness in liquid models,
21
salt perception in the mouth has
been found to be enhanced by pulsatile stimulations.
22
This
principle has been further extended to layered gels that alter-
nate between low and rich domains of tastants, showing that
heterogeneous distribution of tastants increases taste percep-
tion.
23,24
It has been proposed that a heterogeneous spatial
distribution of salt in complex food matrices could help in the
maintenance of salt perception in low-salt bread and hot
snacks.
25
Recently, a large contrast in salt concentration in a
hot served four-layered cream based food was reported to
enhance the perception of saltiness.
26
Moreover, it is
noteworthy that similar observations were reported on aroma
perception for a heterogeneous distribution of volatile
compounds in gels.
27,28
Another strategy currently under investigation to compen-
sate for sensory loss in low-salt food proposes to take advan-
a
CNRS, UMR6265 Centre des Sciences du Goût et de l’Alimentation, F-21000 Dijon,
France. E-mail: salles@dijon.inra.fr; Fax: +33 380 69 32 27; Tel: +33 380 69 30 79
b
INRA, UMR1324 Centre des Sciences du Goût et de l’Alimentation, F-21000 Dijon,
France
c
Université de Bourgogne, UMR Centre des Sciences du Goût et de l’Alimentation,
F-21000 Dijon, France
This journal is © The Royal Society of Chemistry 2015 Food Funct.
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online
View Journal

tage of the cross-modal interactions between odour and taste
to enhance taste intensity.
29–31
The perception of flavour is
hence a multisensory process involving the integration of taste
and odour as a function of their congruency, relying on consu-
mers’previous food experiences, memory or culture.
32,33
Indeed, perceptual interactions can occur when taste and
odour are congruent, so that taste can modulate smell and vice
versa.
29,34–36
Numerous studies have investigated taste–odour
interactions on sweet perception, but few have studied the salt
perception.
37–39
It was recently demonstrated that salt-associ-
ated odour can increase the salt perception of water solutions
containing a low concentration of sodium chloride.
40
Odour-
Induced Saltiness Enhancement (OISE) was also found to be
operant in low-salt solid food matrices.
41
Until now, the strategies proposed to compensate for salt
reduction in food products could compensate for a 25% to
30% sodium reduction.
11
It is likely that a method to compen-
sate for higher reductions in the salt level in processed food
would rely on the combination of several strategies. In the
present study, we set out to examine whether the hetero-
geneous spatial distribution of salt associated with a hetero-
geneous spatial distribution of a salt-associated aroma would
enhance salty taste perception and significantly and additively
increase saltiness perception compared to results obtained for
a single strategy. Since we were interested in evaluating
whether such a combined strategy could help to maintain con-
sumer acceptability for low-salt everyday food, we performed
our sensory experiments with a panel of consumers rating
salty taste intensity and liking for hot-served multilayered-
cream-based model snacks which were designed with the
same total amount of sodium and salt-associated aroma but
varied in their spatial distribution.
Experimental
Materials
The multilayered model snack consisted of a four-layered
cream-based product (FLP) made of whipping cream (30% fat)
(LNA, Le Moulin Henry, France), pasteurised eggs (Blanchard,
Lannergat, France), Emmental cheese (Tippagral, Dijon,
France), modified food starch (Colflo 67, National Starch &
Chemical, Hamburg, Germany), T80 wheat flour (Elevia, Fay-
moreau, France), xanthan gum (Rhodigel Easy, Rhodia Food,
France), table salt (Salin du Midi, Aigues-Mortes, France), ham
aroma (Silesia, Gouvieux, France) and mineral water (Evian,
France). Dry ingredients were stored at room temperature and
wet ingredients were stored at 4 °C. The same batch of raw
materials was used to make all the products for both studies.
Preparation of the four-layered products
Ten FLPs containing the same total amount of salt and ham
aroma, 5‰(w/w) and 0.5‰(w/w), respectively, were pro-
duced. The spatial distribution of salt and aroma was different
from one layer to another (Fig. 1). The products were coded
according to the distribution of salt (S) and ham aroma (A). In
the indices, the letter
H
refers to a homogeneous distribution
of stimuli, whereas the numbers
1
to
4
refers to the spatial
localisation of stimuli in the product; for example, S
1
–A
4
refers
to the product with salt added in the top layer (1) and aroma
added in the bottom layer (4). Moreover, a FLP without added
ham aroma was used as an unflavoured reference (S
H
) and an
unflavoured FLP containing 35% more salt was used as a
saltier reference (S
H+
).
The FLPs were prepared according to a well-established pro-
cedure.
26
All the ingredients were mixed for 2 min (400 W
mixer, Seb, Selongey, France), the xanthan gum (Rhodigel
Easy, Rhodia Food, France) was added, and the dough was
mixed again for 2 min. The dough was spread in silicon
moulds (Flexipat, Demarle, Wavrin, France) and heated at
140 °C for 17 min in a vertical convection oven (Tecnox, Inox-
trend, Lucia Di Piave, Italy). Each layer (average thickness
0.5 cm) was chilled for 30 min at room temperature. The four
layers were piled-up, and in order to make the layers stick
together they were stored at −20 °C for 30 min. The four-
layered matrices were then cut into small pieces (2.5 × 2.5 cm;
9.5 g ± 0.5). The FLP samples were stored for 3 weeks at
−20 °C, in aluminium trays closed on top with a cardboard lip,
until reheating on the day of analysis (sensory, liking and
physicochemical analyses).
Rheological measurements
To ensure that the various spatial distributions of salt and
aroma did not alter the rheological properties of the FLP,
Texture Profile Analysis (TPA) was performed on each product
(4 replicates) with a Texture Analyser TA HD plus (Stable Micro
Systems, England) at 21.5 °C.
On the day of analysis, the frozen FLP samples were pre-
pared in the same way as for sensory and liking evaluations
but they were allowed to cool until room temperature. The
samples were then placed at 21.5 °C for 20 min for tempera-
Fig. 1 Four-layered cream-based products. Black numbers on the left indicate the added salt concentration in each layer, grey italic numbers on
the right indicate the added ham aroma concentration in each layer.
Paper Food & Function
Food Funct. This journal is © The Royal Society of Chemistry 2015
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

ture equilibration prior to analysis. The temperature of the
samples was controlled before TPA measurements.
Two-cycle compressions were performed at a constant
speed of 0.5 mm s
−1
. The FLP samples were compressed with
a plate of 10 cm until a deformation rate of 75% of the initial
height was induced. After a backup at 1.5 mm s
−1
, a second
cycle compression was run under the same conditions. The
developed forces were measured with a load cell (30 kg). The
obtained parameters were, as already described,
42
the hard-
ness (N), cohesiveness (dimensionless), springiness (mm) and
adhesiveness (N mm).
Salt concentration measurements
HPLC Ionic Chromatography (ICS Chain 3000, Dionex, Voisins
le Bretonneux, France) was used to determine the overall salt
content of the whole FLP and in each layer (in triplicate) to
check for between-layer salt diffusion. Sodium was analysed
with an IonPac CS12A column 5 μm at 25 °C and detected by
conductivity with a CSRS 300 2 mm suppressor. A piece of
sample (1 g) was dispersed in 15 mL purified water (MilliQ
system, PureLab, ELGA, UK) using ultraturax® apparatus (Ika,
Werke, Sweden) at 13 500 rpm for 2 min, then centrifuged for
5 minutes at 10 000g(Dutscher, Brumath, France). The
obtained supernatant was diluted in MilliQ water and filtered
(filter pore size 0.45 μm, CIL, Sainte-Foy-la-Grande, France).
H
2
SO
4
(11 mM) was used as the eluent at a flow rate of 0.5 mL
min
−1
. The injection loop was set at 20 µL. The system control
and data acquisition were performed using UCI-100 Chrome-
leon software (version 6.8, Dionex, Voisins le Bretonneux,
France).
Aroma concentration measurements
A headspace/solid phase micro-extraction/gas chromato-
graphy/mass spectrometry (HS-SPME-GC-MS) method was
used to evaluate the diffusion of volatile components between
the four layers of the model snacks.
Samples. Among the twelve FLP products, five presenting
various spatial distributions of salt and ham aroma were
selected to characterise between-layer aroma diffusion. More-
over, in order to increase sensitivity, the FLP recipe was modi-
fied as follows: a tracer, ethyl propanoate (Sigma Aldrich,
Saint-Quentin-Fallavier, France), was added to the ham aroma
at a concentration of 50 µL kg
−1
while the ham aroma concen-
tration was increased up to 3‰(w/w). These FLPs (Table 2)
were prepared and cooked following the procedure previously
described (see the Preparation of the four-layered products
section). The concentration of the aroma compounds was
measured on the whole products and in each layer in order to
evaluate the overall aroma concentration and between-layer
aroma diffusion. For a comparison between the different FLPs,
only the peak area of the aroma compounds was considered.
Analysis of aroma compounds. An optimisation of the
extraction conditions for the volatiles to be analysed was per-
formed in a preliminary study (not shown). The final con-
ditions were as follows. The odorant extractions were carried
out by placing 7 g of FLP mixed with 7 g of MilliQ water into
20 mL vials. Each FLP sample was prepared in triplicate. The
vials were immediately closed with a septum cap and placed in
the incubator of an automatic autosampler (GERSTEL MPS 2,
Gerstel Inc., Mülheim an der Ruhr, Germany) at 30 °C for
120 min. Subsequently, a DVB/CAR/PDMS (Stableflex 2 cm–
50/30 µm) SPME fibre (Supelco Co. Bellefonte, USA) coated
with porous carbon was introduced into the vial and exposed
to the headspace of the samples for 45 min and then injected
into a gas chromatograph. All the odorant extractions were per-
formed using the same SPME fibre.
The SPME fibre was inserted into the splitless/split injector
(250 °C for 5 min in splitless mode, and an additional 10 min
in split mode in order to regenerate the fibre) of a gas
chromatograph (GC, HP6890 Hewlett-Packard, Palo Alto, CA)
equipped with a fused-silica capillary DB-WAX column (30 m,
0.32 mm i.d., film thickness 0.5 µm; Agilent, Folsom, CA,
USA). The linear velocity of the carrier gas, helium, was 44 cm
s
−1
. The GC oven temperature was programmed from 40 °C to
240 °C at a rate of 3 °C min
−1
and held at 240 °C for 10 min.
Mass spectrometry was performed on a mass selective detector
model MS 5973 (Agilent Technologies, Palo Alto, CA) operated
in electron impact mode (70 eV). The mass spectrometer
scanned masses from m/z29 to 350. The ion source tempera-
ture was set at 230 °C. The identification of the volatile com-
pounds was carried out by comparison of their mass spectra
with those of the standard compounds and with those from
the Wiley library and also by comparing their retention
indexes with those of standard compounds and data from the
literature. Linear retention indexes (RI) of the compounds
were calculated using a series of alkanes (C
10
–C
30
) injected
under the same chromatographic conditions.
For quantification, the mass spectrometer was used in
selected ion monitoring (SIM) mode: ethyl propanoate, m/z75,
57, 102; limonene, m/z68, 93, 136; 2-acetylthiazole, m/z99,
127, 112; 2-methoxyphenol, m/z109, 81, 124. The quantifi-
cations were achieved with ion m/z68 for limonene, m/z75 for
ethyl propanoate, m/z99 for 2-acetylthiazole, and m/z109 for
2-methoxyphenol. These ions, which were not present in the
unflavoured reference (S
H
), were chosen for their relative ion
abundances and lack of interference with other compounds.
Sensory evaluations
This study was carried out in accordance with the relevant
institutional and national French regulations and legislation
(Comité de Protection des Personnes Est-1, France, no. 2011/
46, and the French Agency for the Safety of Healthcare Pro-
ducts, AFSSAPS, France, no. 2011-A00807-34) and with the
World Medical Association Helsinki Declaration as revised in
October 2008. All the subjects signed an informed consent
form and were compensated for their participation (10 euros
for a one-hour session). All sessions took place in an air-
conditioned (21 ± 1 °C) tasting room of the Chemosens platform
(INRA Dijon) with single booths equipped with FIZZ® software
(Biosystèmes, Couternon, France). During the sensory sessions
and before each tasting, the frozen samples were heated in a
vertical convection oven (Tecnox, Inoxtrend, Lucia Di Piave,
Food & Function Paper
This journal is © The Royal Society of Chemistry 2015 Food Funct.
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

Italy) for 4 min at 240 °C and served 1.5 min later at 55 °C. The
temperature of the samples was controlled using an electronic
temperature probe Checktemp1 Pocket Thermometer (HANNA
instruments, Dutcher, France).
Panel selection procedure. One hundred and twenty nine
consumers (84 women, 45 men, mean age 44) participated in a
preliminary selection test in which they were asked to evaluate
the taste and flavour intensity of cottage cheese samples.
These samples were made of cottage cheese (20% fat content,
Maîtres laitiers du Cotentin, Sottevast, France) in which one of
the following tastants or aromas was added: sodium chloride
(Cooper, Melun, France), saccharose (Cooper, Melun, France),
lactic acid (Fisher Scientific, Fair Lawn, NJ), anhydride caffeine
(Cooper, Melun, France), monosodium glutamate (Cooper,
Melun, France), ham aroma (Silesia, Gouvieux, France) or
Emmental cheese aroma (Silesia, Gouvieux, France). Three
different concentrations for each tastant or odorant were used,
so that a total of 21 different cottage cheese samples were
tested by the panel. Participants were asked to rate the inten-
sity of tastes (salty, sweet, sour, bitter, umami) and aroma
(ham, Emmental cheese) on linear scales from 0 to 10 (0: very
weak, 10: very strong). The samples were evaluated according
to a monadic evaluation procedure and presented in a
balanced order according to a William Latin square design.
Panellists were asked to cleanse their mouth with Evian water
between each sample.
Points were attributed according to the correct rating
(expected ranking) of the 3 concentrations for each descriptor
as follows: 2 points when the 3 concentrations were rated in
the correct order, 1 point when 2 adjacent concentrations were
inverted, 0 points in other cases. To be selected for the study
on FLP, panellists had to obtain (i) at least 1 point for the salt
ranking test, (ii) at least a total of 7 out of 14 points (7 attri-
butes × 2 points), which is the maximum score for all tests,
and (iii) no more than 2 zero point instances among all tests.
Eighty-two consumers (58 women, 24 men, between 19 and 71
years of age, mean age 44) were finally selected for the sensory
study on FLP.
Selected participants declared that they were not suffering
from food and other allergies and had no problem perceiving
taste or smell. They were requested not to smoke and eat one
hour before the sensory sessions.
Descriptive analysis. The 12 FLPs were evaluated in the
same session according to a monadic evaluation procedure
and presented in a balanced order according to a William
Latin square design. Red light was used to minimise visual
cues.
The 82 panellists were asked to eat the whole product
sample (2 samples of each product were served) and to rate
taste intensity (sour, bitter, salty, sweet and umami) and per-
ceived aroma intensity (ham and Emmental cheese) on linear
scales from 0 to 10 (0: very weak, 10: very strong). A warm-up
sample, i.e., the FLP with a homogeneous distribution of salt
and aroma (S
H
–A
H
) was presented first in order to familiarise
panellists with the product and the task. This sample was not
included in the data analyses. Each panellist consumed a
maximum of 228 g of FLP for the session. A one-minute break
was imposed between each product, while panellists were
asked to cleanse their palate with apple in order to quickly
eliminate the fat layer coating the mouth and then with
mineral water (Evian, France) to cleanse apple particles.
Liking test. The liking test, carried out under the same con-
ditions as for the descriptive analysis, with the same batch of
products and with the same panel, took place 2 weeks later.
The participants were asked to eat the whole product and to
rate their liking on a linear scale from 0 to 10 (0: I do not like,
10: I like very much).
Data analyses
All data analyses were carried out using STATISTICA® Software
(version 10, StatSoft, France). Analyses of variance (ANOVA)
and multivariate analysis of variance (MANOVA) were carried
out with a general linear model (GLM). Student–Newman–
Keuls (SNK) tests were used for post hoc multiple comparisons
of the means. For all data analyses, the effects were considered
significant when p< 0.05.
Results and discussion
Rheological properties
Measurements were carried out to control the influence of the
spatial distribution of salt and ham aroma on the rheological
properties of the FLP. A 2-way MANOVA was performed on the
4 measured rheological parameters (hardness, cohesiveness,
springiness and adhesiveness) with products and replications
as fixed factors. A weakly significant replication effect was
found (Wilk’sλ= 0.19, F(12, 79.7) = 2.2, p= 0.020), but not a
significant product effect. This result indicated that salt and
aroma distributions had no effect on the rheological pro-
perties of FLP. The replication effect could result from slight
inhomogeneity in the sample heating process, which could
have induced slight between-product differences.
Salt concentration and diffusion
The actual salt concentration in the FLPs was measured by
HPLC, which allowed for the assessment of salt diffusion
within the products. The measured salt concentrations in the
different layers ranged between 3.3‰and 20.8‰according
to the product configuration (Table 1) while the salt concen-
tration in the cream-based product without added salt was
4‰(SD = 0.3). A 2-way ANOVA (replications and products as
fixed factors) on the overall salt concentration in the FLPs
revealed no significant replication effect, but a significant
product effect (F(11, 22) = 3.16; p= 0.011). Post-hoc multiple
comparisons of means indicated that, as expected, only the
35% more salted reference (S
+
) contained significantly more
salt than all the other samples (Table 1). ANOVA were also
carried out on the salt concentration in each layer of each
product (layer and replication as fixed factors). For each FLP,
no significant replication effect was found. For samples with
homogeneous salt distribution (S
H
,S
H+
,S
H
–A
H
,S
H
–A
1
,S
H
–A
2
),
Paper Food & Function
Food Funct. This journal is © The Royal Society of Chemistry 2015
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

Table 1 Salt concentrations measured, in triplicate, by HPLC in the whole four-layered cream-based products and in each layer. The final salt concentrations were measured at the moment of
consumption, i.e., after pre-cooking, freezing, and final baking. According to the Student–Newman–Keuls test, the same capital letters indicate no significant difference between products for
the overall salt concentration, whereas the same small letters indicate no difference between layers for the final salt concentration. sd: standard deviation
Product name Product design
Overall NaCl
concentration Layer 1 Layer 2 Layer 3 Layer 4
(‰) sd NaCl (‰)* sd NaCl (‰)* sd NaCl (‰)* sd NaCl
a
(‰)sd
Homogeneous salt distribution products
S
H
7.09
A
1.1 7.6
a
0.1 7.11
a
0.9 7.32
a
0.5 7.23
a
0.7
S
H
+ 11.1
B
1.8 12.33
a
0.6 13.08
a
1.8 12.15
a
3.3 11.99
a
0.5
S
H
–A
H
7.52
A
0.4 8.53
a
0.6 7.32
a
0.2 7.37
a
0.4 8.39
a
1.0
S
H
–A
1
7.44
A
0.4 8.64
a
0.6 7.78
a
0.2 7.87
a
0.6 9.57
a
1.1
S
H
–A
2
8.86
A
0.7 8.98
a
0.5 8.18
a
0.5 8.63
a
0.6 9.07
a
0.8
Heterogeneous salt distribution products
S
1
–A
H
7.66
A
1.2 12.5
a
1.4 8.37
b
0.7 4.20
c
0.1 3.32
c
0.1
Food & Function Paper
This journal is © The Royal Society of Chemistry 2015 Food Funct.
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

Table 1 (Contd.)
Product name Product design
Overall NaCl
concentration Layer 1 Layer 2 Layer 3 Layer 4
(‰) sd NaCl (‰)* sd NaCl (‰)* sd NaCl (‰)* sd NaCl
a
(‰)sd
S
2
–A
H
7.03
A
1.1 7.4
b
0.7 10.67
a
0.3 7.20
b
0.5 3.78
c
0.6
S
1,3
–A
1,3
9.34
A
0.2 10.41
b
0.7 6.73
c
0.2 11.6
a
0.4 7.02
c
0.1
S
1
,–-A
2,4
8.68
A
0.8 10.79
a
0.4 8.07
b
1.2 7.9
b
0.5 6.42
c
0.0
S
1
–A
1
8.34
A
2.5 17.63
a
2.2 8.74
b
0.2 4.20
c
0.5 3.38
c
0.2
S
2
–A
2
9.44
A
0.2 11.11
a
1.3 11.61
a
0.4 8.90
ab
0.3 4.85
b
0.4
S
1
–A
4
8.82
A
1.4 20.84
a
1.8 8.21
b
0.8 4.43
c
0.6 3.92
c
0.4
a
Final NaCl concentration. For product design, salt and aroma contents are in ‰.
Paper Food & Function
Food Funct. This journal is © The Royal Society of Chemistry 2015
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

no significant layer effect was found (Table 1). For the samples
containing two salted layers (S
1,3
–A
1,3
,S
1,3
–A
2,4
), a significant
layer effect was found (F(3, 6) > 27.8, p< 0.00012). Post-hoc ana-
lysis showed that the actual salt distribution resulted in three
different concentration levels instead of the expected two. For
the products containing only one salted layer (S
1
–A
H
,S
2
–A
H
,
S
1
–A
1
,S
2
–A
2
,S
1
–A
4
), the 2-way ANOVAs revealed significant
layer effects (F(3, 6) > 45.3; p< 0.0001). For the samples S
1
–A
H
,
S
1
–A
1
, and S
1
–A
4
,post hoc analyses showed that the salted layer
(layer 1 or 4) was significantly different from the other three
layers in which no salt was added, but the just adjacent non-
salted layer was also significantly different from the other two
non-salted layers (Table 1). For the sample S
2
–A
H
, the salted
layer (layer 2) contained significantly more salt than non-
salted layers 1 and 3, which were also significantly different
from the non-salted layer 4 (Table 1). For the sample S
2
–A
2
, the
salted layer (layer 2) was significantly different only from layer
4 (Table 1). These results highlighted that salt diffusion
occurred from the salted layer to the adjacent non-salted layers
depending on the salted layer position within the product.
However, despite salt diffusion likely induced by the heating
process, the heterogeneity of salt distribution in the products
remained in conformity with the experimental design.
Aroma diffusion
The actual aroma compound concentrations in the FLPs were
measured by HS-SPME-GC-MS. Moreover, as the heating
process can modify the initial spatial distribution of the
aroma, the actual aroma compound concentrations (related to
the peak area) were measured in each layer to check whether
heterogeneity of aroma distribution was maintained. A 2-way
MANOVA (replications and products as fixed factors) was
carried out on the peak area of the 4 monitored ions (m/z68,
m/z75, m/z99, m/z109) corresponding to the 4 aroma com-
pounds studied. No significant replication effect was found,
but a significant product effect was revealed (Wilk’sλ= 0.004,
F(16, 15.9) = 5.1, p= 0.001). Post-hoc tests indicated no signifi-
cant difference between FLPs for the 2-acetylthiazole (m/z99)
and 2-methoxyphenol (m/z109). However, the S
1
–A
4
product
tended to contain less ethyl propanoate (tracer, m/z75) than
the 4 other aromatised products (Table 2). In this product, and
compared to the S
1
–A
1
one, no salt was added in the aroma-
tised layer resulting in the lowest salt concentration associated
with aroma compounds (Table 1). This could have affected the
aroma compound release by decreasing the release as a conse-
quence of a lower salting out effect.
43–45
Moreover, such an
effect has likely been observed only for ethyl propanoate
because this aroma compound was added at a higher concen-
tration (tracer) and because the salting out effect has been
reported to depend on the polarity of the aroma com-
pounds.
12,46
Subsequently, 2-way MANOVA was performed for
each FLP on the 4 monitored ions with replication and layer as
fixed factors (Table 2). For FLPs with a homogeneous aroma
distribution (S
H
–A
H
and S
1
–A
H
models), no significant effect of
replication or layer factors was found. These results indicated
that no aroma diffusion occurred between layers during
heating of the products with a homogeneous aroma distri-
bution, regardless of salt distribution. For FLPs with a hetero-
geneous aroma distribution (S
H
–A
1
,S
1
–A
1
,S
1
–A
4
), 2-way
MANOVA yielded no significant effect of replication, but a sig-
nificant effect of the layer factor (Wilk’sλ> 0.00006, F(12, 8.2)
> 23.3, p> 0.0001). Post-hoc tests indicated that aroma com-
pounds diffused differently through the layers. For ethyl pro-
panoate (m/z75), the layer in which ham aroma was added
(layer 1) contained a higher concentration of this volatile com-
pound than the adjacent layer (layer 2) which itself contained
a higher concentration than the 2 remaining layers (layer 3
and 4). For limonene (m/z68), the diffusion was the highest
since the adjacent layer (layer 2) contained a similar limonene
concentration as layer 1 in which this odorant had been
added. Layers 3 and 4 contained a significantly lower limonene
concentration, although not negligible, in comparison with
the concentration found in layer 1. For the 2-acetylthiazole
(m/z99) and 2-methoxyphenol (m/z109), post-hoc tests revealed
that only the layer in which ham aroma was added (layer 1)
contained a higher concentration of these volatile compounds
than the other 3 layers.
Overall, these results indicated that diffusion of the volatile
compounds between layers during the heating process
occurred and depended mostly on the compound, namely its
chemical properties, but not on the salt concentration in the
layers. Because of this diffusion process the initial design of
aroma distribution was only partially maintained after the
heating process so that the initial aroma concentration con-
trast was softened.
Sensory evaluation
Descriptive analysis. A series of mixed-effects ANOVA
(panellists as a random factor and products as a fixed factor)
were carried out, respectively, on sweetness, sourness, bitter-
ness, umami, saltiness, Emmental cheese and ham aroma
intensity ratings. No significant product effect was found for
sweetness (M= 1.43, SD = 1.74), bitterness (M= 1.20, SD =
1.74), sourness (M= 1.29, SD = 1.74), umami taste (M= 1.75,
SD = 2.04) and Emmental cheese aroma intensity (M= 2.70,
SD = 2.22). For ham aroma (M= 2.16, SD = 2.21) a significant
effect of the product factor (F(11, 883) = 6.25, p< 0.001) was
observed. Post-hoc tests showed that ham aroma was perceived
as more intense in products containing aroma, compared to
the reference lacking aroma (S
H
) (Fig. 2).
For saltiness (M= 3.96, SD = 2.37), ANOVA yielded a signifi-
cant product factor effect (F(11, 884) = 7.33, p< 0.0001). To
assess the increase in perceived saltiness, we evaluated salti-
ness enhancement, which is the difference calculated for each
panellist between (i) the score obtained for aromatised pro-
ducts or saltier reference (S
H+
) and (ii) the score obtained for
the reference lacking aroma (S
H
). The ANOVA on saltiness
enhancement indicated a significant panellist effect
(F(81, 891) = 7.30, p< 0.0001) as well as a significant effect of
products (F(11, 891) = 6.56, p< 0.0001). Means for saltiness
enhancement were significantly higher than 0 for all aroma-
tised products and the saltier reference (Fig. 3). Interestingly,
Food & Function Paper
This journal is © The Royal Society of Chemistry 2015 Food Funct.
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

Table 2 Quantification of the volatile compounds measured by HS-SPME-GC-MS on the whole four-layered cream-based products and in each layer. Mean values represent the peak area (arbi-
trary units ×10
3
) for each of the monitored ions: m/z68 for limonene, m/z75 for ethyl propanoate, m/z99 for 2-acetylthiazole, and m/zfor 109 for 2-methoxyphenol. According to the Student–
Newman–Keuls test, the same capital letters indicate no significant difference between the products for the final overall volatile compound concentration, and the same small letters indicate no
difference between the layers for the final overall volatile compound concentration. sd: standard deviation
a
Product
name Product design
Overall peak area (sd) Final peak area Layer 1 (sd) Final peak area Layer 2 (sd) Final peak area Layer 3 (sd) Final peak area Layer 4 (sd)
68 75 99 109 68 75 99 109 68 75 99 109 68 75 99 109 68 75 99 109
Homogeneous salt distribution product models
S
H
–A
H
20.9
AB
15 415.9
AB
36.9
A
169.2
A
18.6 12 761.7 34.2 39.3 14.9 14 891.6 39.3 193.7 28.9 13 888.8 36.6 165.6 29.0 10 146.4 34.5 165.3
2.5 782.2 1.2 1.7 2.0 431.3 0.9 2.4 0.3 342.8 2.4 24.4 3.7 682.4 0.8 4.9 4.9 1070.9 0.6 4.0
S
1
–A
H
15.2
B
18 444.4
A
52.1
A
221.5
A
10.1 14 324.6 46.5 49.3 16.2 16 236.9 49.3 223.1 16.0 16 564.7 54.9 259.0 11.6 17 969.2 59.7 318.7
2.9 868.9 1.8 5.4 0.6 1101.5 7.0 1.7 0.9 857.4 1.7 2.8 3.4 628.4 4.4 37.7 0.6 1140.3 6.2 43.9
Heterogeneous salt distribution product models
S
H
–A
1
13.6
B
14 644.3
AB
43.3
A
186.5
A
21.2
a
19 133.0
a
117.0
a
714.6
a
9.3
b
14 195.6
b
37.4
b
121.3
b
14.4
ab
4664.2
c
10.1
b
23.5
b
9.5
b
3087.6
c
8.2
b
34.2
b
2.3 1565.6 4.4 19.9 2.9 841.0 16.7 150.0 0.4 985.3 2.5 9.3 2.8 34.7 0.7 3.1 0.9 141.8 0.7 3.4
S
1
–A
1
18.2
B
17 129.7
AB
58.2
A
281.0
A
24.9
a
18 902.9
a
144.1
a
904.7
a
22.4
a
12 365.8
b
43.9
b
156.2
b
14.1
b
6446.7
c
10.5
b
21.5
b
12.9
b
4709.1
c
8.9
b
27.4
b
8.0 4556.5 12.7 81.9 1.2 1056.5 17.1 130.3 3.2 796.1 1.2 10.0 1.3 806.1 0.6 2.6 0.9 427.2 0.8 5.0
S
1
–A
4
25.2
A
11 568.7
B
44.1
A
210.1
A
13.5
b
1651.9
c
8.4
b
34.0
b
33.1
ab
2127.7
c
6.7
b
24.8
b
36.1
ab
8533.4
b
31.3
b
118.0
b
47.2
a
14 293.3
a
117.3
a
725.5
a
0.3 726.4 7.8 46.3 1.8 251.8 1.0 0.5 2.2 167.9 0.7 2.3 0.3 263.5 2.4 16.6 9.6 274.6 19.6 144.4
a
For product design, salt and aroma contents are in ‰.
Paper Food & Function
Food Funct. This journal is © The Royal Society of Chemistry 2015
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

saltiness enhancement increased with the increasing hetero-
geneity of salt distribution. This was the case when salt was
concentrated in only one layer, especially the external layer (S
1
;
Fig. 3). Moreover, multiple comparisons of means revealed
that only when salt and aroma were concentrated in one exter-
nal but different layer (S
1
–A
4
) the saltiness enhancement was
significantly higher compared to a homogeneous distribution
of the same amount of salt (S
H
). Conversely, the distribution
of salt and aroma in two layers (S
1,3
–A
2,4
) did not produce
more enhancement compared to the homogeneous distri-
bution of both salt and aroma (S
H
–A
H
).
Liking test. Liking scores ranged from 4.4 to 5.8, which
suggested that FLP samples were rather well accepted by con-
sumers, taking into account that ratings were performed
under laboratory conditions. Despite the low variability of the
liking scores (1.4 on a scale of 10), an ANOVA (panellists as
random factors, products as fixed factors) was carried out on
liking scores and revealed a significant effect of the product
factor (F(11, 902) = 3.1, p= 0.0005). However, post-hoc tests did
not show a significant difference between products and the
references (S
H
) or with the saltier reference containing 35%
more salt (S
H+
) as reported in Fig. 4. A Pearson correlation was
carried out on the mean saltiness and liking ratings for all the
FLPs. Results indicated no correlation between saltiness and
liking ratings (r(12) = −0.038, p= 0.8).
General discussion
In the present study we investigated the combined effects of
heterogeneous salt and aroma distribution in hot-served
snacks on salty taste perception, with the aim to compensate
for salt reduction while maintaining consumer acceptability.
Heterogeneity of the distribution of tastants that enhanced
taste perception has been described in liquid solutions and
gels,
24,47
but few studies have investigated the influence of the
heterogeneous spatial distribution of salt on the salty taste of
solid food products.
25,48
Recently, a saltiness enhancement
was observed for layered snack foods served at a hot tempera-
ture that varied in salt distribution.
26
These authors high-
lighted that salt perception was primarily dependent on the
composition of the salty layer and that the final salt concen-
tration in the saltier layer was the key driver of enhanced
saltiness in layered cream-based products. In that case,
heterogeneous spatial distribution of salt was shown to com-
pensate for a decrease in 20% of the total amount of salt in
the product. In addition, odour enhancing taste perception
has been described in liquid solutions. Odours were reported
to enhance sweetness,
38,39
sourness,
49
bitterness
50
and salti-
ness.
40
The influence of adding salt-associated odours on salty
taste perception in solid food products has been investi-
gated.
41
They reported odour induced saltiness-enhancement
(OISE) for Comté cheese and sardine odours in model cheese,
Fig. 2 Perceived ham aroma intensity for each four-layered cream-
based product. Error bars represent the standard error of the means.
Same letters indicate that means are not significantly different at a level
of 5%.
Fig. 3 Saltiness enhancement mean scores for each four-layered
cream-based product. Saltiness enhancement was calculated with this
equation for each participant: (score obtained for four-layered cream-
based products) –(score obtained for the unflavoured reference (S
H
)).
Error bars represent the standard error of the mean. The asterisks indi-
cate a significant saltiness enhancement: ***p< 0.001; **p< 0.01;
*p< 0.05 (t-test). The same letters indicate that the means for saltiness
enhancement were not different at a significance level of 5% (SNK).
Fig. 4 Mean liking scores for each four-layered cream-based product.
Error bars represent the standard error of the mean. *p< 0.05.
Food & Function Paper
This journal is © The Royal Society of Chemistry 2015 Food Funct.
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

which contribute to increased overall salty taste perception by
15%.
To our knowledge, no study has focused on OISE and
heterogeneous salt distribution as a combined strategy to com-
pensate for decreased saltiness in low-salt food products.
However, combining several compensation strategies was
found to be efficient to increase the percentage of salt
reduction that could be achieved without a loss of perceived
saltiness. For instance, taste–taste and odour–taste perceptual
interactions were successfully combined to significantly
enhance saltiness perception in water solutions containing
salt, citric acid and sardine aroma.
51
The results of the present
study confirmed the usefulness of coupling several strategies
since we were able to combine odour-induced saltiness
enhancement and heterogeneous spatial distribution of salt to
design a hot-served snack (S
1
–A
4
) that was more salty and as
well liked as a standard snack containing 35% more salt (S
H+
).
Using warm food products to study food flavour perception
is always a challenge because the heating process influences
the taste and flavour perception. It was demonstrated that a
higher serving temperature lowered saltiness intensity; pro-
ducts can thus lose 10 to 20% of saltiness intensity according
to the type of food and the salt concentration.
52
Moreover,
heating induces many chemical and textural modifications
that particularly increase the diffusion of water and volatile
compounds. This is a common issue in layered food products
with a heterogeneous distribution of water soluble com-
ponents (i.e., salt) and aroma compounds (i.e., volatiles)
because heterogeneity can be disrupted during the heating
process. Indeed, heating of snack foods was reported to induce
salt diffusion which was a limiting factor for maintaining
heterogeneous salt distribution and therefore for the enhance-
ment of salt perception.
26
In the present study, diffusion of
salt from the layers in which salt was concentrated to the salt-
free adjacent layers was also observed. For example, in the
S
1
–A
1
product up to 50% of the salt added in the upper layer
diffused to the adjacent salt layers. Nevertheless, even after
diffusion was boosted by the heating process, the differences
in salt concentrations remained significant in all the layered
configurations, which ensured sufficient heterogeneity of salt
spatial distribution to induce saltiness enhancement. Indeed,
saltiness enhancement was significantly higher for the 5 pro-
ducts with added salt located in only one layer, especially
when the salt was concentrated in an external layer, which con-
firmed previously obtained data.
26
Diffusion was also important for the added aromas, but
depended on their chemical nature. For instance, in the S
1
–A
1
product the diffusion from the layer containing the added
ham aroma into the other 3 layers was approximately 60–40%
for the limonene and the ethyl propanoate. Hence, probably as
a consequence of aroma compound diffusion boosted by the
heating process, we found no significant enhancement of ham
aroma intensity induced by the initial heterogeneous spatial
distribution of aroma compounds (Fig. 2). The diffusion issue
could explain the difference between our results and those
reported by others, which showed that heterogeneity of the
spatial aroma distribution in gels increased perceived aroma
intensity.
27,28
Nevertheless, added ham aroma significantly
contributed to enhanced saltiness regardless of its spatial dis-
tribution (Fig. 3). Therefore, the combined strategy allowed
compensation for a higher amount of salt reduction compared
to the heterogeneous distribution of salt alone.
26
Moreover,
because ham aroma intensity was quite low in the present
study as a consequence of aroma diffusion in the products,
one can expect a greater enhancing effect of aroma by either
increasing aroma intensity and/or by limiting aroma com-
pound diffusion.
Beyond taste and flavour perception, liking is the main
driver of food acceptability. For our experimental hot-served
snacks we obtained quite high liking scores (approximately
5 of 10).
53
We did not find that products with a heterogeneous
distribution of salt and/or aroma compounds were signifi-
cantly less appreciated (Fig. 4) which is in line with the results
of other studies using heterogeneous spatial distribution of
tastants in food products.
26,48
However, it is possible that, due
to the rather limited number of subjects included in the liking
experiment, small differences in liking may have been under-
estimated. Therefore, our results suggest that the combination
of heterogeneous distribution of salt associated with odour-
induced saltiness enhancement does not alter food liking and
is a suitable strategy to maintain flavour intensity and
especially saltiness in low-salt food without loss of acceptabil-
ity, even after a 25% decrease of salt. Moreover, such a strategy
may be extended to compensate for sugar and fat reduction,
which could help manufacturers follow public health agencies’
recommendations in terms of reductions in salt, sugar or
fat while maintaining a good acceptability of food products for
consumers.
Acknowledgements
The authors are very grateful to Céline Lafarge (AgroSup Dijon,
France) for assistance in the texture profile analysis measure-
ments, as well as to Karine Gourrat and Etienne Semon (Plat-
form Chemosens, CSGA, Dijon, France) for assistance in the
aroma diffusion measurements. The authors also acknowledge
the Regional Council of Burgundy and FEDER for their finan-
cial participation in this study.
References
1 G. A. MacGregor, Nephrol. Dial. Transplant., 1998, 13, 2471–
2479.
2 P. Strazzullo, L. D’Elia, N.-B. Kandala and F. P. Cappuccio,
Br. Med. J., 2009, 339, b4567.
3 N. Campbell, R. Correa-Rotter, B. Neal and F. P. Cappuccio,
Nutr. Metab. Cardiovasc. Dis, 2011, 21, 617–619.
4 Dietary Guidelines Advisory Committee, Report of the
Dietary Guidelines Advisory Committee on the Dietary
Guidelines for Americans to the Secretary of Agriculture
Paper Food & Function
Food Funct. This journal is © The Royal Society of Chemistry 2015
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online

and the secretary of health and human services, US
Department of Agriculture, Agriculture Research Service,
Washington DC, USA, 2010.
5 AFSSA, Rapport du groupe de travail sur le sel, Paris, 2002.
6 World Health Organization, Reducing Salt Intake in Popu-
lations: Report of a WHO Forum and Technical Meeting,
Geneva Switzerland, 2007.
7 World Health Organisation, Creating an enabling environ-
ment for population-based salt reduction strategies: report
of a joint technical meeting held by WHO and the Food
Standards Agency, Geneva Switzerland, 2010.
8 C. M. D. Man, in Reducing salt in foods, ed. D. Kilkast and
F. Angus, Woodhead Publishing Limited, Cambrigde,
England, 2007, pp. 157–173.
9 P. J. Taormina, Crit. Rev. Food Sci., 2010, 50, 209–227.
10 T. E. Lawrence, M. E. Dikeman, M. C. Hunt, C. L. Kastner
and D. E. Johnson, Meat Sci., 2003, 65, 967–972.
11 D. G. Liem, F. Miremadi and R. S. J. Keast, Nutrients, 2011,
3, 694–711.
12 L. Boisard, C. Tournier, E. Semon, E. Noirot, E. Guichard
and C. Salles, Flavour Frag. J., 2014, 29,95–106.
13 C. Walsh, in Reducing salt in foods, ed. D. Kilkast and
F. Angus, Woodhead Publishing Limited, Cambrigde,
England, 2007, pp. 124–133.
14 P. A. S. Breslin and G. K. Beauchamp, Nature, 1997, 387,
563.
15 S. Bouhlal, C. Chabanet, S. Issanchou and S. Nicklaus,
PLoS One, 2013, 8, e53971.
16 M. Mitchell, N. P. Brunton and M. G. Wilkinson, Food
Qual. Prefer., 2013, 28, 356–360.
17 F. Toldra and J. M. Barat, Recent Pat. Food Nutr. Agric., 2009,
1,80–86.
18 F. Toldra and J. M. Barat, Recent Pat. Food Nutr. Agric, 2012,
4,19–25.
19 J. L. H. C. Busch, F. Y. S. Yong and S. M. Goh, Trends Food
Sci. Technol., 2013, 29,21–34.
20 H. L. Meiselman and B. P. Halpern, Physiol. Behav., 1973,
11, 713–716.
21 K. M. M. Burseg, H. L. Lieu and J. H. F. Bult, Chem. Senses,
2012, 37,27–33.
22 J. L. Busch, C. Tournier, J. E. Knoop, G. Kooyman and
G. Smit, Chem. Senses, 2009, 34, 341–348.
23 A. C. Mosca, F. van de Velde, J. H. F. Bult, M. A. J. S. van
Boekel and M. Stieger, Food Qual. Prefer., 2010, 21, 837–
842.
24 K. Holm, K. Wendin and A.-M. Hermansson, Food Hydro-
colloid, 2009, 23, 2388–2393.
25 M. W. J. Noort, J. H. F. Bult, M. Stieger and R. J. Hamer,
J. Cereal Sci., 2010, 52, 378–386.
26 M. Emorine, C. Septier, T. Thomas-Danguin and C. Salles,
Food Res. Int., 2013, 51, 641–647.
27 S. Nakao, S. Ishihara, M. Nakauma and T. Funami,
J. Texture Stud., 2013, 44, 289–300.
28 S. Nakao, S. Ishihara, M. Nakauma and T. Funami, Food
Sci. Technol. Res., 2013, 19, 675–683.
29 C. Murphy and W. S. Cain, Physiol. Behav., 1980, 24, 601–
605.
30 C. Murphy, W. S. Cain and L. M. Bartoshuk, Sens. Proc.,
1977, 1, 204–211.
31 D. Valentin, C. Chrea and D. H. Nguyen, in Optimising
sweet taste in foods, ed. W. J. Spillane, Woodhead Publish-
ing Limited, Cambridge, England, 2006, pp. 66–84.
32 D. M. Small and J. Prescott, Exp. Brain Res., 2005, 166, 345–
357.
33 J. Lim, T. Fujimaru and T. D. Linscott, Food Qual. Prefer.,
2014, 34,5–13.
34 R. A. Frank and J. Byram, Chem. Senses, 1988, 13, 445–455.
35 H. N. J. Schifferstein and P. W. J. Verlegh, Acta Psychol.,
1996, 94,87–105.
36 B. G. Green, D. Nachtigal, S. Hammond and J. Lim, Chem.
Senses, 2012, 37,77–86.
37 M. Cliffand A. C. Noble, J. Food Sci., 1990, 55, 450–454.
38 J. Djordjevic, R. J. Zatorre and M. Jones-Gotman, Exp. Brain
Res., 2004, 159, 405–408.
39 D. Labbe, A. Rytz, C. Morgenegg, S. Ali and N. Martin,
Chem. Senses, 2007, 32, 205–214.
40 G. Lawrence, C. Salles, C. Septier, J. Busch and T. Thomas-
Danguin, Food Qual. Prefer., 2009, 20, 241–248.
41 G. Lawrence, C. Salles, O. Palicki, C. Septier, J. Busch and
T. Thomas-Danguin, Int. Dairy J., 2011, 21, 103–110.
42 M. C. Bourne, Food Technol., 1978, 66,32–62.
43 W. G. Jennings, Food Sci., 1965, 30, 445–449.
44 R. Martinez, M. Teresa Sanz, S. Beltran and E. Corcuera,
J. Chem. Eng. Data, 2012, 57, 1480–1485.
45 S. Ventanas, S. Mustonen, E. Puolanne and H. Tuorila,
Food Qual. Prefer., 2010, 21, 453–462.
46 L. Boisard, I. Andriot, C. Martin, C. Septier, V. Boissard,
C. Salles and E. Guichard, Food Chem., 2014, 145, 437–444.
47 A. C. Mosca, J. A. Rocha, G. Sala, F. van de Velde and
M. Stieger, Food Hydrocolloid, 2012, 27, 448–455.
48 A. C. Mosca, J. H. F. Bult and M. Stieger, Food Qual. Prefer.,
2013, 28, 182–187.
49 R. J. Stevenson, J. Prescott and R. A. Boakes, Chem. Senses,
1999, 24, 627–635.
50 G. Caporale, S. Policastro and E. Monteleone, Food Qual.
Prefer., 2004, 15, 219–227.
51 N. Nasri, C. Septier, N. Béno, C. Salles and T. Thomas-
Danguin, Food Qual. Prefer., 2013, 28, 134–140.
52 T. R. Rosett, T. Hamill, K. Morris and B. P. Klein, J. Food
Sci., 1997, 62, 421–424.
53 I. Boutrolle, D. Arranz, M. Rogeaux and J. Delarue, Food
Qual. Prefer., 2005, 16, 704–713.
Food & Function Paper
This journal is © The Royal Society of Chemistry 2015 Food Funct.
Published on 23 March 2015. Downloaded by RSC Internal on 22/04/2015 14:02:23.
View Article Online