Sensory characterization of dry-cured ham using free-choice profiling
Trang 1Sensory characterization of dry-cured ham using free-choice profiling
IRTA-Centro de Tecnologia de los Alimentos, Finca Camps i Armet, E-17121 Monells, Spain
Article history:
Received 19 February 2009
Received in revised form 19 August 2009
Accepted 19 August 2009
Available online 23 August 2009
Keywords:
Free-choice profiling
Consumer perception
Dry-cured ham
Sensory properties
a b s t r a c t
In this study, free-choice profiling was carried out to study how consumers perceived and described the sensory properties of dry-cured ham One hundred and nine consumers from three different Spanish regions evaluated the sensory characteristics of four different commercial dry-cured hams aged with age-ing times of 6, 9, 12 and 16 months Data were analysed by means of Generalized Procrustes Analysis In order to understand the sensory consumers’ vocabulary better a Quantitative Descriptive Analysis with seven trained assessors was also performed In general, results showed that consumers used simple terms
to describe the sensory characteristics of the samples, paying special attention to the appearance, espe-cially, the colour and fat content of the dry-curedham There was some disagreement in the case of salty taste and texture descriptors, but, apart from that a consensus in the use of sensory attributes was observed Data from trained assessors proved to be a useful method for understanding and validating consumers’ vocabulary
Ó 2009 Elsevier Ltd All rights reserved
1 Introduction
The sensory quality of dry-cured ham results from the
interac-tions between the characteristics of the fresh matter and the
Guerrero, & Sárraga, 1998; Buscailhon, Gandermer, & Monin,
1994; Parolari, Virgili, & Schivazappa, 1994; Vestegaard,
Schivaz-appa, & Virgili, 2000) The extent of these changes depends on
the initial composition of the raw material and the technological
process (Buscailhon, Berdagué, & Monin, 1993) and the ageing
duration (Guàrdia, Guerrero, Gou, Monfort, & Arnau, 1999) In
addition to these factors affecting sensory properties, there are
fur-ther aspects such as habits of consumption (Mili, Mahlau, &
Furi-tsch, 1996) and socio-cultural characteristics related to the
geographical region (Cilla et al., 2006) that also affect consumers’
quality perception of dry-cured ham
Sensory descriptive tests are among the most sophisticated
tools used by sensory scientists (Lawless & Heymann, 1998) and
involve the discrimination and description of both the qualitative
and quantitative sensory components (Meilgaard, Civille, & Carr,
1991) Several different methods exist within descriptive analysis
that reflect different sensory approaches (Lawless & Heymann,
1998) Quantitative Descriptive Analysis (QDA) is a technique
fre-quently used in sensory characterization of food In this respect,
several authors (Cilla, Martínez, Beltrán, & Roncalés, 2006;
García-González et al., 2006; Guerrero, Gou, Alonso, & Arnau,
1996; Rousset & Martin, 2001) have used trained panels to
describe the sensory properties of different types of dry-cured ham However, QDA is very time-consuming due to the extensive training that assessors must undergo Furthermore,Piggott, Sheen, and Apostolidou (1990)pointed out that trained and experienced assessors normally tend to generate complex and scientifically ori-ented terms in sensory research which may be difficult for non-specialized people to understand
Free-choice profiling (FCP) is a sensory methodology that differs from other descriptive methods because it is not necessary to use a common vocabulary of attributes to describe the samples, nor are the panellists expected to agree on their interpretation of the terms used By means of FCP, each participant produces their own descriptive profiles of the products, without having to explain the exact meaning (Williams & Langron, 1984) This is based on the assumption that panellists do not differ in their perceptions, but merely in the way in which they describe them FCP is similar
to traditional profiling in that assessors must be able to detect dif-ferences between the samples, verbally describe the perceived attributes and quantify them (Oreskovich, Klein, & Sutherland,
1991) The FCP strategy can yield important insights into consumer differentiation of products and establish relationships between consumer preferences and sensory characteristics (Jack & Piggott,
1992) The analysis of the data collected from FCP is normally
1975; Langrom, 1983) This statistical technique allows for the rationalization of the spatial configurations derived from individ-ual profiles The result is a consensus configuration revealing the interrelationships between the samples for the panel as a whole (Williams & Langron, 1984) Regarding the number of attributes generated, this is limited only by the perceptual and descriptive 0950-3293/$ - see front matter Ó 2009 Elsevier Ltd All rights reserved.
* Corresponding author Tel.: +34 972 630052; fax: +34 972 630373.
E-mail address: lluis.guerrero@irta.es (L Guerrero).
Contents lists available atScienceDirect Food Quality and Preference
j o u r n a l h o m e p a g e : w w w e l s e v i e r c o m / l o c a t e / f o o d q u a l
Trang 2skills of the consumer (Oreskovich et al., 1991) and, according to
Deliza, MacFie, and Hedderley (2005), terms used by untrained
assessors may vary, based on their individual experience and
familiarity with the product To summarize, FCP offers the
possibil-ity of assisting the demands of marketing and product
develop-ment teams who require information on target consumer’s
perception of products, rather than the more technical descriptions
of the products typically provided by trained sensory panels
(Elmore & Heymann, 1999; Murray, Delahunty, & Baxter, 2001)
The aim of this study was to evaluate how consumers
repre-senting three different Spanish regions perceive and describe
sen-sory characteristics of four different types of commercial dry-cured
ham using FCP Furthermore and, in order to surmount the
incon-venience related to the interpretation of the consumers’
vocabu-lary, a QDA with trained assessors was used to facilitate
comprehension of the terms generated by consumers
2 Materials and methods
2.1 Dry-cured ham sample preparation
Four types of commercial Spanish dry-cured ham from white
pig breeds with aging times 6, 9, 12 and 16 months (samples A,
B, C and D, respectively) were selected to provide a wide range of
sensory variability and to stimulate the generation of attributes
by consumers Three dry-cured hams of each type were boned,
cut at the head of the femur level and then sliced (1.5 ± 0.2
mm-thick) perpendicularly to the femur axis in the distal part direction
(Fig 1) with a vertical slicer Kolossal 350 BVK (Marconi, Italy) So
that the panellists were not distracted by testing cuts from
differ-ent areas of the dry-cured ham (Guerrero, Guàrdia, & Arnau, 2004,
2005), the slices evaluated by each consumer were from the same
anatomical position for each one of the four dry-cured hams
assessed
Slices were placed inside polypropylene trays, packed in bags
per-meability: 7 cm3/m2/24 h at 4 °C and 80% RH; CO2 permeability:
1150 cm3/m2/24 h at 23% and 75% RH; water-vapour permeability:
1.5 g/m2/24 h; SACOLIVAÒ, S.L., Castellar del Vallès, Spain) under
modified atmosphere (99.8 ± 0.1% N2 and 0.1 ± 0.1% O2) with an
oxygen scavenger (Tyvek LH3000, ATCO) and then stored at
2 °C ± 2 °C for a maximum period of 7 days
2.2 Physicochemical description of samples Moisture and fat content of six slices per ham were analysed by near infrared transmittance (NIT) spectroscopy with an INFRATECTM
1265 Meat Analyzer (Tecator AB, Sweden) NaCl content was
Physico-chemical composition of dry-cured hams used in the study is shown inTable 1
2.3 Descriptive sensory analysis 2.3.1 Free-choice profiling (FCP)
A group of 109 consumers aged between 21 and 68, recruited in the Centre (Madrid) (n = 34), South (Sevilla) (n = 37) and North (Girona) (n = 38) of Spain, participated in the study The recruit-ment was randomly made by phone, using a filter questionnaire specifically elaborated for this study, including demographic and socio-economic information (gender, age, education level, and working situation) and frequency of consumption of different food products including dry-cured ham Only consumers who declared eating ham at least once every two weeks, and with no previous experience in sensory analysis, were selected
To avoid the effect of storage time on the sensory properties of dry-cured ham, sensory evaluation of the samples was carried out
in all three cities in the same week Two FCP sessions with 15–20 consumers each were carried out per city Participants were re-ceived in a conference room and placed at individual tables under white lighting (700 lx ± 150 lx) First of all, consumers were briefed
on the concept of the methodology and the procedure The aim of this was to allow for development of the vocabulary to describe the four types of dry-cured ham Each consumer was given one slice of each of the four dry-cured hams They were instructed to include only objective attributes and not to use hedonic terms During this task, the consumers were first asked to describe the appearance and the odour of the samples After, they were requested to taste the sample and to describe the flavour and texture characteristics writing their personal perception in their own words Then, each consumer once again received one slice of each type and scored the four types of dry-cured ham using his/her own previously gen-erated descriptors In this case, the same hams were presented but with different codes and in a different order All samples were as-sessed in the same tasting session balancing the first-order and carry-over effects (Macfie, Bratchell, Greenhoff, & Vallis, 1989) Sensory attributes were evaluated using an unstructured 100 mm line scale anchored with the words ‘‘absence” and ‘‘intense” at each end
In all sessions, slices of dry-cured ham were evaluated at room temperature (20 °C) and presented on white plastic plates covered with a food grade PVC film (oxygen permeability; 20,000 cm3/m2/
b
a
20 mm 25 mm
c
b
a
20 mm 25 mm
c
Fig 1 Schematic view of the dry-cured ham sampling: (a) sample for
physico-chemical analysis; (b) sample for sensory analysis (QDA) and (c) sample for
Table 1 Least square means and RMSE for moisture, fat content and NaCl and each type of dry-cured ham (n = 3).
Moisture (%) <0.0001 51.34 a
48.17 a 50.71 a 40.65 b 3.035 Fat content (%) 0.0002 6.83 b
12.36 b
7.13 b 19.68 a 4.001 NaCl (%) <0.0001 6.05 a 5.10 b 5.63 a 4.79 b 0.231 a,b
Within a row, least square means with different superscripts differs significantly (p < 0.05).
RMSE: root mean standard error.
* A = 6, B = 9, C = 12 and D = 18 months of ageing time, respectively.
Trang 324 h; water-vapour transmission rate 2000 g/m2/24 h; Macopal,
S.L., Lliçà de Vall, Spain) to prevent drying Samples were coded
with three-random numbers and, for each consumer, all the
sam-ple slices came from the same anatomical position Mineral water
and unsalted crisp-bread were provided to rinse consumers’
mouths between samples
2.3.2 Quantitative Descriptive Analysis (QDA)
Seven selected and trained assessors (ASTM, 1981; ISO 8586-1,
1993; ISO 8586-2, 1994) undertook the sensory analysis on 1.5 mm
slices from the same dry-cured hams (n = 12, three dry-cured hams
and four ageing times) previously evaluated by the consumers The
generation of the descriptors had been carried out in open
discus-sion in two previous sesdiscus-sions The descriptors retained were:
sweetness (basic taste sensation elicited by sugar), saltiness (basic
taste sensation elicited by NaCl), bitterness (basic taste sensation
elicited by caffeine andL-tryptophan), metallic (flavour similar to
a solution of FeSO47H2O), piquantness (stinging sensation in the
mouth and throat), matured flavour (set of complex nuances
char-acteristic of dry-cured meat products, not described by other
fla-vour attributes), aged (flafla-vour related to aged fat which is
characteristic of long aged Spanish dry-cured ham partially
skinned according to the typical V shape;Gou, Arnau, & Guàrdia,
which the surface of the ham slice adheres to the palate when
com-pressed with the tongue), hardness (amount of pressure required
to completely compress the sample), crumbliness (textural
prop-erty characterized by ease with which a sample can be separated
into smaller particles during chewing), pastiness (feeling of paste
detected in hams with a high proteolytic index), fibrousness
(tex-tural property characterized by the perception of the amount of
muscle fibres detected during chewing) The references used to
illustrate the maximum intensity of hardness, crumbliness and
(1999) A non-structured scoring scale (Amerine, Pangborn, &
Roessler, 1965) was used, where 0 meant absence of the descriptor
and 10 meant high intensity of the descriptor Sensory evaluation
was undertaken in three sessions and a complete block design
was used (Steel & Torrie, 1960–1983), where each taster assessed
the four different types of dry-cured ham in each session Samples
were coded with three-random numbers and were presented to
the assessors balancing the first-order and the carry-over effects
were evaluated in slices from the same anatomical area
2.4 Data analysis
2.4.1 Free-choice profiling data analysis
Data from the FCP was submitted to Generalized Procrustes
Analysis, and a consensus matrix was obtained by using
mathe-matical data operations according toArnold and Williams (1986)
The average of all transformed configurations that shows the
min-imum overall deviation was obtained as a consensus space It
sum-marizes the information on the samples and replaces the panel
mean (Langrom, Williams, & Collins, 1984) Similar terms were
grouped together in order to simplify the map obtained Only
agreed descriptors with correlation coefficients higher than 0.6 in
at least one of the first two dimensions and mentioned by more
than eight consumers were used to visualize the relationships
be-tween samples and attributes
The frequency of descriptors used by consumers in each city
& Belsius, 1994), including gender, age, education level, working
situation and consumption frequency of each consumer as
supple-mentary variables
Statistical analyses were carried out using XLSTAT software (Addinsoft, France)
2.4.2 Quantitative descriptive data analysis Data from the Quantitative Descriptive Analysis was analysed
(2001) The ANOVA test was performed over the mean score (seven assessors) for each dry-cured ham because each dry-cured ham is the experimental unit (when performing sensory analysis all the assessors evaluate the same ham) The model included the type
of dry-cured ham (ageing time) and the taste session as fixed ef-fects The interaction assessor type of dry-cured ham was tested and dropped from the model since it was not significant (p > 0.05) Differences between treatments were tested by the Tukey test Fur-thermore, a Principal Component Analysis was carried out on the mean score for each dry-cured ham
2.4.3 Physicochemical data analysis Data from physicochemical analysis were submitted to one-way ANOVA (SAS, 2001) including the type of dry-cured ham (age-ing time) as a fixed effect Mean comparisons were carried out using the Tukey test
3 Results and discussion Demographic, socio-economic characteristics and frequency of dry-cured ham consumption of the consumers involved in the present study are shown inTable 2 About 44.0% of the consumers were men and 56.0% women and most of them were aged between
20 and 50 (80.7%) The final age distribution of the consumers who participated in the present study showed a bias when compared with the Spanish population (33.41% of which are older than 50; INE, 2007) This bias may be explained by the additional selection criteria used of consumption frequency – eat ham at least once every two weeks Normally, people aged over 50–55 tend to reduce salt and fat consumption in order to prevent cardiovascular risk factors (Black, 2000) and both are present in dry-cured ham A large percentage of consumers had a medium education level (45.9%) similar to the Spanish average (48.03%,INE, 2001) and, 67.9% of them were employees In this case, the official data (INE,
Table 2 Demographic, socio-economic characteristics and frequency of dry-cured ham consumption of the participants (% of respondents, n = 109).
Socio-demographic characteristic % of respondents Gender
Age
Education level
Working situation
Consumption frequency
Trang 4population aged over 16 and in this sense our sample was also
slightly biased
Almost half of the respondents (47.7%) stated that they
con-sumed dry-cured ham two or three times a week, 22.9% more than
three times a week, 18.3% once a week and 11.0% less than once a
week These results may be explained by the high Spanish
be-cause the consumption of dry-cured ham (higher than once every
two weeks) was one of the criteria of recruitment These results are
in agreement with those obtained byCilla et al (2006), Resano,
Sanjuán, and Albisu (2007) and Morales, Guerrero, Claret, Guàrdia,
and Gou (2008)
The results obtained that each consumer in FCP used 10
attri-butes, on average, to describe differences between samples The
number of attributes ranged from 4 to 20 (Fig 2) Most of the terms
used by consumers (39.7%) referred to appearance, 26.5% to
fla-vour, 17.9% to texture and 15.9% to odour The high number of
con-sumers’ words dealing with appearance (n = 431) agrees with
Guerrero, Aguiar, Guàrdia, Claret, and Arnau (2007)which stated
that this is the most important factor for Spanish consumers in
pointed out that visual attributes are easier to describe than the
oronasal senses, because vision and hearing are an inborn
mecha-nism, whereas the other senses rely largely on learning
Table 3 shows the frequency of occurrence for the most
fre-quent attributes mentioned by consumers Colour, intensity of
dry-cured ham odour, saltiness, intensity of dry-cured ham flavour
and fat content were mentioned by more than 59% of the
respon-dents On taking into account the consumer response, it can be
sta-ted that the aforementioned descriptors probably represent the
most important sensory attributes in dry-cured ham or, according
toKöster (2003), the easiest to elicit In a similar way,Resano et al
(2007)observed that 90% of consumers from the central Spanish
region considered colour, fat and salty taste as very or quite
impor-tant in dry-cured ham selection Also,Morales et al (2008)found
that more than 70% of consumers from Catalonia (Northeast part
of Spain) pointed out that colour, salty taste, aged flavour and
tex-ture were the most important parameters affecting the purchase of
dry-cured ham
Fig 3shows the graphic results of GPA over the consumer
sen-sory profiles The variance accounting for the first two components
was 83.7% Similar descriptors used by different assessors and
lo-cated in the same area in the first two dimensions have been
grouped In these cases the size of the descriptor is proportional
Schlich, & Lesschaeve, 1992) The results obtained revealed that
sample D (with the highest ageing time) located in the negative area of the first dimension was mainly defined by colour, dry-cured ham odour and flavour and fat content and, to a lesser degree (the smaller letter size) by marbling, saltiness, texture, matured flavour, juiciness and appearance Conversely, sample A (with the least age-ing time) located in the positive direction of the first axis was char-acterized by hardness, dryness, saltiness and atypical flavour/ odour attributes Ageing is referred to as one of the main factors responsible for developing sensory characteristics of dry-cured ham due to biochemical reactions that occur throughout this pro-cess (Flores, Ingram, Bett, Toldrá, & Spanier, 1997) In this study, another consideration to explain the differences observed between samples A and D is their different physicochemical composition, particularly in fat and moisture content (Table 1) Dry-cured hams
B and C show intermediate characteristics within this first dimen-sion of the consensus space However, the second dimendimen-sion
con-Table 3 Frequency of occurrence for the most frequently elicited descriptors.
Spanish)
Frequency a (%) Colour (dark, red) Color, color oscuro, rojo 87.2 Odour intensity (dry-cured ham
odour)
Olor, olor a jamón 75.2 Saltiness, amount of salt Salado, cantidad de sal 72.5 Flavour intensity (dry-cured ham
flavour)
Sabor, intensidad, a jamón
66.1
White spots Pintas blancas, puntos
blancos
19.3
homogeneidad
9.2
a Percentage of respondents (n = 109).
0 5 10 15 20
number of atributes
undefined appearance odour taste texture
Trang 5trasts sample B in the positive direction, with sample C in the
neg-ative Sample C is described as having white spots, matured,
salti-ness and tendersalti-ness attributes
Some discrepancies were observed among consumers regarding
perception of saltiness in this study Conversely, Parolari (1994)
did not observe these differences in a similar investigation
per-formed on Italian Parma hams Saltiness was located in the four
areas defined by the first two dimensions, which means that they
were not used in the same way by the participants Saltiness is a
basic taste and a well-known sensory attribute, so agreement
among consumers would be expected This apparent contradiction
detected in saltiness can be explained by the fact that salt content
(NaCl) in Spanish dry-cured ham is very heterogeneous,
particu-larly when there are important differences in moisture content
be-tween muscles (Arnau, Guerrero, Casademont, & Gou, 1995) Since
several consumers only tasted a portion of the slices provided, this
could have contributed to the discrepancies in saltiness perception
among them Another possible explanation for this contradictory
result is that dry-cured ham is a product with high salt content
O’Mah-ony (1986)explains that when a stimulus is experienced (i.e., a
product is tasted), some residue remains in the mouth The taste
system adapts to such residual stimuli rendering it less sensitive
to such stimuli, and when tasted subsequently the high salt
con-tent will taste less intense In order to reduce any desensitization
due to adaptation, unsalted crisp-bread and mineral water were
provided to rinse the mouth at the beginning of the session and
be-tween samples However, it is probable that all the consumers did
not follow these recommendations fully Conversely, the trained
assessors always tasted the central part of each slice containing a
portion of semimembranosus and biceps femoris muscles in order
to block differences in salt content between them Furthermore,
trained panellists are aware of the fact that the taste system adapts
to residual stimuli when dry-cured ham is tasted and they follow
the abovementioned instructions In our opinion these are the
main reasons for explaining why the problems observed in the
consumer study were not observed in the QDA study
Hardness, fibrousness and tenderness attributes also showed a
slight disagreement (Fig 3) Some consumers described sample A
as hard in the positive direction of the first dimension However,
fibrousness, hardness and tenderness descriptors were also placed
in the negative area of this first dimension, close to sample D Fur-thermore, tenderness was also explained by the second dimension and related with sample C in the negative direction of this axis Again, this discrepancy could be due to the slice portion tasted
by each consumer, since external muscles (semimembranosus) are
Ruiz-Ramírez, Arnau, Serra, & Gou, 2006) The meaning of the term tex-ture (located in the negative area of the first dimension) is not eas-ily interpreted, as it is of a multidimensional concept and therefore
a number of confusing attributes come together In this sense, Szc-zesniak (2002)stated that consumers have difficulty in describing texture due to its complex nature, since there are no single and specific receptors for it, in contrast to other sensory attributes, such as colour and taste Therefore, the apparent discrepancy ob-served in our results could be due to the fact that consumers have different ways of describing their perceptions, depending on indi-vidual experiences, preferences and familiarity with the product (Deliza et al., 2005) In addition, they may also differ considerably
in their ability to express themselves (Lachnit, Busch-Stockfisch, Kunert, & Krahl, 2003)
Dry-cured ham samples were also sensory evaluated by a trained panel to clarify and understand the consumer vocabulary better Least square means corresponding to the sensory descrip-tors are shown inTable 4 (in this table, n = 3 means that three dry-cured hams of each ageing time were sensory evaluated) The total number of different descriptors generated by the trained panel was slightly higher than those from the consumers Con-versely,Moskowitz (1983)stated that trained panellists use fewer descriptors than those untrained, because it seems that the effort expended in accurate description replaces the effort used to cap-ture all attributes Ten of the selected descriptors by the expert pa-nel were discriminant (p < 0.05) between dry-cured hams Samples
A and D were different in eight of the twelve descriptors used, however, B and C only differed in five of them (Table 4) Fig 4 shows the graphic results of PCA over the sensory descriptors from the trained panel and dry-cured ham samples
The results obtained with GPA (Fig 3) and PCA (Fig 4) are com-plementary to each other and sample location was similar among
(1997)also obtained similar results when they compared sensory profiles from expert and semi-trained assessors In this study, sam-ples A and D were differentiated by the first dimension, whereas B and C were separated by the second dimension The comparison
D
B
C
A
colour
fat
odour
flavour
saltiness
marbling
odour
flavour
texture
hard
cured
white spots
atypical flavour/odour juiceness
saltiness tender
cured
tender
appearance
saltiness
saltiness
dry
soft
brightness
fibrous/hard
shape
rancid
-1
-0.5
0
0.5
1
Dimension 1 (57.2%)
Fig 3 Consensus space obtained using Generalised Procrustes Analysis over the
sensory consumer profile of dry-cured ham (the letters represent the dry-cured ham
samples) The size of each descriptor is proportional to the number of assessors who
agree on their use Only those descriptors having a correlation coefficient higher or
equal 0.06 with one of the two first dimensions of the consensus space are shown.
Table 4 Least square means and RMSE for each sensory descriptor and for each type of dry-cured ham obtained from the sensory analysis (n = 3).
Flavour Sweetness 0.3 c
0.8 bc
1.1 ab
1.9 a
0.665
2.2 ab
2.0 bc
1.0 c
0.975 Piquantness 2.1 a
1.4 ab
1.7 ab
0.9 b
1.242 Matured flavour 2.4 b
3.0 b
4.7 a
5.6 a
1.168 Aged flavour 0.3 c
0.7 c
2.3 b
4.2 a
1.110 Texture
Adhesiveness 1.1 b
1.8 a
1.0 ab
1.6 ab
0.999
3.0 b
4.0 a
3.2 b
0.615 Crumbliness 4.2 b
4.7 ab
5.1 a
5.3 a
0.855
a,b,c Within a row, least square means with different superscripts differs signifi-cantly (p < 0.05).
RMSE: root mean standard error.
*
Trang 6betweenFigs 3 and 4allows us to ascertain the sensory attributes
behind consumer vocabulary Dry-cured ham sample A, defined as
bitter, piquant and metallic in PCA was described as having an
atypical flavour/odour in GPA Atypical flavour/odour is a
compila-tion of several words such as feed, male, acid and different
off-odour or off-flavour attributes used by consumers that had similar
location on the consensus space Hardness and fibrousness as
re-ferred mainly to sample A by the trained panel, could mean hard
and dry texture in consumer words The crumbliest dry-cured
ham sample D is characterized by juiciness, texture, tender and
soft in the GPA consensus space Likewise, odour, flavour and
ma-tured terms mentioned by consumers (GPA) could be interpreted
as sweetness, matured and aged flavour in the trained panel
vocab-ulary (PCA) Samples D were also the dry-cured hams with the
highest fat content (Table 1), which accordingly have been related
to higher sweetness and juiciness (Guàrdia, Guerrero, Gispert,
Gar-nier, & de Vries, 1999) and matured flavour (Bolzoni, Barbieri, &
Virgili, 1996; Flores et al., 1997)
As expected, consumers in general used a large number of
unspecific descriptors (colour, taste, odour, appearance and
tex-ture) compared to the trained assessors Some attributes used by
the trained panel i.e., metallic, aged, pastiness, crumbliness,
adhe-siveness were not elicited by more than three consumers, probably
due to the fact that most consumers were either not familiar with
these attributes or did not know their meaning On the other hand,
consumers showed great ability in describing appearance,
high-lighting several features like colour, fat content, marbling,
bright-ness, white spot presence, size and shape In contrast,Hersleth,
Berggren, Westad, and Martens (2005)found in a study on bread
that Norwegian consumers were more efficient in describing
tex-ture attributes than other sensory characteristics These different
results could be due to the fact that consumer sensory perception
tends to be specific for a product, since it provides a different
de-gree of importance to different sensory attributes depending on
the particularities of each food product, and texture seems to be
a more important aspect in bread than ham It is important to
no-tice as well that these differences may be due to the existence of a
different awareness of descriptive terms between Norwegian and
Spanish consumers and the lack of defective texture in the
dry-cured ham samples tasted
Fig 5 shows the results obtained by means of Simple
Corre-spondence Analysis over the contingency table of the different
descriptors elicited by consumers for each city and gender Since age, education level and work situation (supplementary variables) did not show significant differences, these variables were not rep-resented inFig 5 Attributes such as brightness, uniform, colour or appearance were most frequently mentioned in Sevilla; juiciness, hardness, matured flavour, white spots and slice size in Madrid; and fat colour, rancid flavour, sinews, dry and tenderness in Girona This last result may be explained by some differences in habits of meat products consumption at home between geographical areas (Mili et al., 1996) According toAskegaard and Madsen (1998) Eur-ope cannot be regarded as a homogeneous sensory culture since important differences exist in consumption patterns, behaviour and attitudes not only between countries but also between regions within the same country In Spain, dry-cured ham consumption patterns differ clearly between regions If we analyze it by geo-graphical areas, the region of greatest consumption is Catalonia, the Basque Country and Madrid, which represent 70% of the con-sumption, followed by Andalucía and Extremadura (in the South-west), and then Cantabria, Navarra, La Rioja, Galicia and Asturias (Comunidad de Madrid, 2006)
Regarding consumers ‘gender and consumption frequency, sig-nificant differences were found Men and more frequent consum-ers (F1 and F2: 2 or more times a week) described dry-cured ham samples by means of colour, marbling, brightness, hardness, matured flavour and juiciness, whereas women and less frequent consumers (F3: once a week or less) tended to use more recurrent descriptors such as sinews, uniformity, fat colour, rancidity, white spots and saltiness Differences between genders in sensory evalu-ation of food products have been described in scientific literature and may be mainly explained by the different sensitivity of men and women (Chauban, 1989; Prodi et al., 2004; Ullrich & Tepper,
2000) or by a different attitude towards different food related as-pects that are frequent between genders (Aaron, Mela, & Evans, 1994; Dennison & Sheperd, 1995; Guerrero et al., 1999; Guàrdia, Guerrero, Gelabert, Gou, & Arnau, 2006; Kähkönen, Tourila, & Rita, 1996; Sheperd, 1988)
4 Conclusions This study indicates the applicability of FCP methodology in or-der to find out how consumers describe dry-cured ham sensorially
metallic
sweetness
saltiness piquantness
bitterness
aged flavour
matured flavour
adhesiveness
hardness crumbliness
pastiness
fibrousness
A A A
B B B
C
D
D
D
-1
-0.5
0
0.5
1
PC1 (56.1%)
Fig 4 Principal Component Analysis of the sensory profile of four dry-cured ham
samples (A, B, C and D).
SEVILLA
MADRID GIRONA
F3
F2F1 WOMEN
MEN
nerves
size
uniform
fat colour
aspect soft rancid
brightness
juiciness white spots
tender
tough dry texture
marbling cured fat flavour saltiness odour colour
-1 -0.5 0 0.5 1
Dimension 1 (63.7 %)
Fig 5 Graphical distribution of dry-cured samples (A, B, C and D) and descriptors for each city obtained using Simple Correspondence Analysis over the contingency table of the generic descriptors of the consumer sensory profile, including gender (men and women) and consumption frequency (F1 = more than three times a week; F2 = two or three times a week; F3 = once a week or less) as supplementary variables.
Trang 7Consumers paid more attention to the appearance of the product.
Most of the attributes selected by participants were elementary,
thus reflecting their simplicity when compared with those
ob-tained from the trained panel Consumers showed a high level of
agreement in the use of sensory attributes, except for saltiness
and texture descriptors The little agreement in these key
dry-cured ham attributes could be a limitation in FCP applied to ham
Our results indicate that the consumer sensory description of
dry-cured ham depends on the geographical region where the
con-sumer lives Trained assessors and concon-sumers describe sensory
attributes of dry-cured ham in a similar way and, in both cases,
they are able to differentiate the ageing times of dry-cured ham
The sensory descriptive profile obtained by means of trained
asses-sors proves to be a useful tool to understand consumers’
vocabu-lary regarding dry-cured ham better
Acknowledgments
The authors would like to acknowledge the Spanish Ministry of
Education and Science/INIA (Project RTA 2006-00060-00-00) for
supporting this research work
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