Caporale Et Al., 2006. Consumer Expectations for Sensory Properties in Virgin Olive Oils.

8/18/2019 Caporale Et Al., 2006. Consumer Expectations for Sensory Properties in Virgin Olive Oils.

1/10

Consumer expectations for sensory properties in virgin olive oils

Gabriella Caporale a,*, Sonia Policastro b, Angela Carlucci a, Erminio Monteleone b

a Smell and Taste Association, Via dell’Edilizia, 85100 Potenza, Italyb Dipartimento di Biologia Difesa e Biotecnologie Agro Forestali, Università degli Studi della Basilicata, Via dell’Ateneo Lucano 10,

Campus Macchia Romana, 85100 Potenza, Italy

Received 1 November 2004; received in revised form 6 July 2005; accepted 8 July 2005Available online 1 September 2005

Abstract

Information has been shown to create expectations concerning sensory properties and acceptability of food products, and toinfluence their evaluations. Studying the impact of information is particularly relevant for traditional products which communicateabout typicality. Extra virgin olive oil is a typical Mediterranean production whose typicality is strongly affected by the origin of itsraw material and the manufacturing technology. The present study aims (1) to explore the appropriateness of several sensorydescriptors in evaluating the typicality of certain extra virgin olive oils, (2) to assess the impact of information about the originof the product on the sensory profile perception, (3) to study how the effect of sensory expectations can influence liking and ‘‘typ-icality’’ responses for the experimental oils obtained from a defined cultivar. Working with a panel of consumers familiar with sev-eral typical extra virgin olive oils produced in Lucania, a set of monovarietal extra virgin olive oils were evaluated. Results show thatthere are well defined expectations for some of the sensory properties which characterize the typical olive oils presented. The sensorydisconfirmations leading to complete assimilation in sensory perception are associated to higher ‘‘typicality’’ ratings. Our results alsorevealed that bitterness and pungency proved to be the most appropriate sensory descriptors of certain typical olive oils.

2005 Elsevier Ltd. All rights reserved.

Keywords: Olive oil; Appropriateness test; Typicality; Expectations; Origin

1. Introduction

The beliefs and attitudes of individuals with regardsto food products are strongly dependent on their cul-tural traditions and on their education and culinary hab-its and they may vary with information (Issanchou,

1996). Recent research on the effects of different typesof information about nutritional qualities, or foodingredients and use, or the origin of raw material, orthe manufacturing process, etc. suggest the possibil-ity that these messages may also generate hedonicexpectations and influence food acceptability. Most of the empirical studies confirm that the influence of

information on liking after tasting could be explainedby an assimilation model as a possible consequence of the occurrence of a disconfirmation phenomenon(Caporale & Monteleone, 2001; Caporale & Montele-one, 2004; Johansson, Haglund, Berglund, Lea, & Ris-vik, 1999; Kähkönen & Tuorila, 1996; Lange,

Rousseau, & Issanchou, 1999; Siret & Issanchou, 2000).Disconfirmation, i.e. the difference between the ex-

pected acceptability of a product and the blind accept-ability of the same product before being affected byexpectations, affects food perception and acceptance.When the stimuli/product is better than expected, thedisconfirmation is positive. Conversely when the stim-uli/product is worse than expected the disconfirmationis negative. A number of predictive models (e.g. assimi-lation and contrast) have been suggested in order to

0950-3293/$ - see front matter 2005 Elsevier Ltd. All rights reserved.doi:10.1016/j.foodqual.2005.07.011

* Corresponding author.E-mail address: [email protected] (G. Caporale).

www.elsevier.com/locate/foodqual

Food Quality and Preference 17 (2006) 116–125

mailto:[email protected]:[email protected]


2/10

explain the effect of discrepancies between expectationsand actual product performance on acceptance (Ander-son, 1973; Cardello & Sawyer, 1992).

Assimilation model occurs when liking of the productmoves in the expectation direction. Thus, when the dif-ferences between liking without (blind) and with infor-

mation (actual) prove to be significantly different fromzero it means that there was a significant effect of writteninformation on hedonic scores and an assimilation oc-curs if liking after exposure to information is influencedin the direction of expected liking. Furthermore, in thecase of assimilation, when expected minus actual likingresults significantly different from zero it means thatthe score in the presence of information was located be-tween the blind score and the expected score, i.e. con-sumers do not completely assimilate towards theirexpectations and assimilation is not total (Siret &Issanchou, 2000). Several authors suggested that if con-sumers do not completely assimilate the discrepancy be-

tween their expectations and perceived quality it can beassumed that they will revise their expectations after re-peated exposures (Deliza & MacFie, 1996; Goering,1985; Lange et al., 1999).

Information about country of origin has a ‘‘tremen-dous influence on the acceptance and success of prod-ucts’’ (Dichter, 1962). Other authors showed thatcountry of origin has a strong influence on product eval-uation (Peterson & Jolibert, 1995). In particular country-of-origin information may be studied as a cognitive cue,an informational stimulus about or relating to a productthat is used by the consumers to infer beliefs regarding

product attributes such as quality (Bilkey & Nes, 1982;Steenkamp, 1990). In addition to its role as a qualitycue, country of origin has symbolic and emotional mean-ing for consumers. So there are cognitive, affective andnormative mechanisms which govern country-of origineffects (Verlegh & Steenkamp, 1999). Some authors re-port that the region-of-origin cue has a direct effect,not only indirect via perceived quality, on regional prod-uct preference for some consumer segments, especiallythose resident in the products region of origin. Productsplace of origin may elicit emotions based on consumer sexperience with the region able to directly affect regionalproduct preference. When consumers are aware of the re-gion, the ‘‘region-of-origin’’ cue triggers consumersassociations with the region, which are then used to eval-uate the product. The stronger and more favourable con-sumers associations with the region are, the greater thelevel of success of regional products (Van der Lans,van Ittersum, De Cicco, & Loseby, 2001).

Typical foods are characterized by a complex qualityprofile defined by several conditions such as geographicorigin, culture, tradition, environmental factors, geneticproperties and the manufacturing process know-how.These factors may affect the sensory profile of productsdetermining their specificity. The typicality of a product

depends therefore upon the detection of certain qualityallowing it to be distinguished from other products of the same commercial category, and for this reason ‘‘typi-cal’’ products are identified with well defined sensoryexpectations by consumers familiar with them. It maybe supposed that the quality of typical food products is re-

lated to the conformance of these products to a character-istic sensory profile, and thus we can assume that whenthese products are experienced and respond in terms of expected and actual sensory profiles, they are acceptedby consumers and present a high quality level.

Amongst typical food products extra virgin olive oilplays an important role as a typical example of Mediter-ranean production whose typicality is strongly affectedby the origin of its raw material and the manufacturingtechnology. In recent years the European Union (EU)has recognised many protected extra virgin olive oils(protected designation of origin or protected geograph-ical indication). These typical oils, which are mainly

famous for their sensory properties, present a complexand specific qualitative profile including both intrinsicand extrinsic factors.

For many years market researchers have addressedthe question of how failure to satisfy expectation affectsconsumer satisfaction of products (Cardello, 1994).However, it is only recently that sensory scientists havebegun to address the question of how expectation effectsmay influence consumer perceptions of sensory attri-butes (Deliza & MacFie, 1996; Deliza, MacFie, & Hed-derley, 2003; Kähkönen & Tuorila, 1998; Lange et al.,1999; Prescott & Young, 2002). Kähkönen and Tuorila

(1998) found that when ‘‘Bologna’’ sausages were la-belled as reduced fat, they were rated as lower in salti-ness and fattiness than a regular sausage, differencesthat were not apparent when no information was given.

Most of the cited studies on the impact of informa-tion on expected and actual sensory properties deal withproducts often unfamiliar to consumers or at least anon-ymous or commercial (Deliza et al., 2003; Kähkönen &Tuorila, 1998; Tuorila, Cardello, & Lesher, 1994). Itwould be very useful when marketing typical productsto investigate how information about the products ori-gin can affect the perception of sensory descriptors andhow the effect of sensory expectations can influence lik-ing and the response of ‘‘typicality’’ according to con-sumers familiar with the product.

The present study was designed to examine the im-pact of information about the origin of the product(production area and cultivar) on the expected and per-ceived hedonic and sensory properties of extra virgin ol-ive oils.

The work explored a possible approach for dealingwith studies related to the measurement of the sensoryexpectations of consumers towards typical productsusing two separate phases: (1) the selection of themost appropriate attributes for describing the sensory

G. Caporale et al. / Food Quality and Preference 17 (2006) 116–125 117


3/10

properties of certain typical oils; (2) the analysis of expectations, generated by information on product ori-gin, towards the most appropriate sensory attributes.

With this approach it was necessary to select consum-ers who were familiar with the typical oils being testedthus justifying the use of a specifically chosen panel.

2. Materials and methods

2.1. Products

Six samples representing three typical extra virgin ol-ive oils produced in Lucania were chosen for the study.These samples were made exclusively from specific olivecultivars growing in specific areas of Lucania. Table 1presents the name and the origin of the six experimentaloils. The oils were produced in November 2003 andtested from January to the end of February 2004 in

order to keep their sensory properties stable. Before andduring the experiment the oils were kept out of the lightand were stored at a controlled temperature (12 C) andhumidity (65%). They were presented to the consumersinto 60-ml dark glasses and served at 25 C. The presen-tation order of the samples followed Williams LatinSquares balanced for first-order and carry-over effects(MacFie, Bratchell, Greenhoff, & Vallis, 1989).

2.2. Consumers

Consumers were recruited at specialized virgin olive

oil shops in Potenza (main town in the region of Lucania,Southern Italy). They were selected using predeterminedscreening criteria based on purchasing and consumptionfrequency as well as familiarity with the typical extravirgin olive oil of Lucania used in the study.

One hundred and eight subjects were interviewed andwere asked to spontaneously give as many names of Lucania oils as they could. For each quoted typicaloil, consumers were asked to report how frequently theypurchased it (1 = never; 2 = less than once a year;3 = once or twice a year; 4 = 3–5 times a year; 5 = lessthan once a month; 6 = once a month; 7 = 2–3 times amonth). Then, they were asked to indicate how fre-quently they consumed it either at home or in a restau-

rant (1 = one a year or less; 2 = less than once a month;3 = 1–3 times a month; 4 = once a week; 5 = 2–4 times aweek; 6 = every day; 7 = more than once a day).

A consumer was included in the panel if he/she: (1)listed at least four of the five typical oils produced inLucania and included in the list the three oils used in this

study; (2) reported buying each of the three selected typ-ical oils at least 3 times a year; (3) reported consumingeach of the three selected typical oils at least 1–3 timesa month. Because of the restrictive criteria used in theselection of consumers, only 34 consumers satisfied allthe conditions and agreed to participate. Thus the con-sumer panel consisted of 15 females and 19 males agedbetween 25 and 50.

2.3. Information

Three forms of information each indicating one of thethree different origins of the six oils (olive cultivars and

their relative production area) were used. One form was‘‘An extra virgin olive oil made exclusively from Cora-tina olives grown in the Vulture area’’. The Ogliarolaand Maiatica oils from the Bradano and Ferrandinaareas respectively were described in the same way.

2.4. Procedures

Consumers participated in seven sessions, at three-day intervals. Each session lasted about 30 min. Allthe tests were conducted in individual sensory boothsand the data were collected with the FIZZ software

ver. 1.31 (Biosystemes, Couternon, France). Table 2summarises the experimental design.

2.4.1. Session 1. Blind-condition-liking of olive oils

and hedonic expectations created by the information

about the origin of the experimental olive oils

During the first session consumers were asked to ratetheir liking of the six experimental oils presented in a blindcondition. After a few minutes they had to rate their likingexpectations for (a) oils produced exclusively from Cora-tina olives grown in the Vulture area; (b) oils producedexclusively from Ogliarola olives grown in the Bradanoarea; (c) oils produced exclusively from Maiatica olivesgrown in the Ferrandina area. During this evaluationthe information about the origin of the oils was shownon the computer screen in each booth and the assessorsdid not have a real product in front of them.

2.4.2. Session 2. Effect of information about the origin

on perceived liking of the experimental olive oils

In this session, consumers were asked to rate theirperceived liking of the six oils presented with the sameinformation used in session one. In this session the threeforms of information really corresponded to the tastedoils (see Table 2).

Table 1Features of the six experimental oils

Product Cultivar Production area

A1 Coratina VultureA2B1 Ogliarola BradanoB2C1 Maiatica FerrandinaC2

118 G. Caporale et al. / Food Quality and Preference 17 (2006) 116–125


4/10

After tasting the products without (session 1) or withinformation (session 2), consumers rated the hedonicresponses (blind, expected and actual) on a 100 mm lin-ear scale ranging from ‘‘Extremely unpleasant’’ at theleft end to ‘‘Extremely pleasant’’ at the right end.

2.4.3. Session 3. Study of the ‘‘typicality’’ of the

experimental oils

In the third session consumers were asked, after tast-ing, to rate the ‘‘typicality’’ of the six experimental oilspresented with the same information that was used insessions 1 and 2. This response was given on a100 mm linear scale ranging from ‘‘Not at all typical’’at the left end to ‘‘Very typical’’ at the right end.

2.4.4. Session 4. Study of the appropriateness of

sensory descriptors of typical extra virgin olive oils

In this session consumers evaluated the appropriate-ness of certain sensory attributes in describing the ‘‘typ-icality’’ of extra virgin olive oils of Coratina, Ogliarolaand Maiatica. Respondents rated the appropriatenessof nine attributes selected from those generally used inthe sensory evaluation of extra virgin olive oils (Mojet& de Jong, 1994): apple, cut grass, almond, artichoke,green olive, tomato, pungency, astringency and bitter-ness. The appropriateness response was rated on a 7-point scale ranging from 1 = ‘‘not at all appropriate’’to 7 = ‘‘extremely appropriate’’, according to the

following instructions: ‘‘Please read carefully the list of sensory attributes shown in the video and rate theappropriateness of each one in describing the ‘‘typical-ity’’ of Coratina, Ogliarola and Maiatica oils.

2.4.5. Session 5. Study of the bitterness and

pungency intensity of oils, both in a blind condition

and as expected in relation to the information

about the origin

In the fifth session, performed after the analysis of re-sults collected in session 3 and the selection of the mosttypical oils, consumers were asked first to evaluate the bit-terness and pungency intensity of the six experimental oilspresented in a blind condition and then to rate theexpected intensity of bitterness andpungencyfor thethreeinformation forms. These sensory descriptors were se-

lected as the most appropriate in describing these typicalextra virgin olive oils. The study of sensory expectationswas carried out using the same procedures as in the studyof liking expectations. The bitterness and pungency inten-sity ratings obtained by consumers in a blind conditionwere related to those obtained by a trained panel.

2.4.6. Session 6. Blind-condition perception of

bitterness and pungency intensity in Coratina oils

In this session consumers rated the bitterness andpungency intensity of Coratina oils evaluated in a blindcondition.

Table 2Summary of the experimental design for the consumer study

Session Stimulus presentation Type of evaluation Type of rating Aim

1 Six typical oils Tasting Liking Study on the oils liking in the blindcondition and hedonic expectationscreated by the information about theorigin of the experimental olive oils

Three forms – Expectation of liking

2 Six typical oils with the formcorresponding to their origin

Tasting Liking Study on the effect of informationabout the origin on actual liking of the experimental olive oils

3 Six typical oils with the formcorresponding to their origin

Tasting Typicality Study of the ‘‘typicality’’ of theexperimental oils

4 Nine sensory descriptors – Appropriateness Study of the appropriateness of sensory descriptors of typical extravirgin olive oils

5 Six typical oils Tasting Bitterness and pungency intensity Study on the oils bitterness andpungency intensity both in blindcondition and as expected in relationto the information about the origin

Three forms – Expected bitterness and pungency intensity

6 Coratina oils Tasting Bitterness and pungency intensity Study on the effect of theinformation about the origin on theperceived bitterness and pungencyintensity in Coratina oils

7 Coratina oils with the formcorresponding to their origin

Tasting Bitterness and pungency intensity



5/10

2.4.7. Session 7. Study of the effect of the information

about the origin on the perceived bitterness and pungency

intensity of Coratina oils

In the last session consumers rated the bitterness andpungency intensity of the experimental oils presentedwith the information reported in session 1.

The sensory ratings were collected on a 100 mm lin-ear scale ranging from ‘‘Not at all’’ at the left end to‘‘Extremely’’ at the right end.

2.5. Sensory analysis by trained panel

In order to test the consistency of the consumer datawith the data obtained from a trained panel, the bitter-ness and pungency intensity of the six experimental oilswas evaluated by a panel of 10 trained judges. The oilswere evaluated in triplicate in evenly balanced se-quences. A 9-point scale ranging from ‘‘Not at all’’ atthe left end to ‘‘Extremely’’ at the right end was used

for this test.

2.6. Data analysis

The study on the occurrence of both hedonic and sen-sory disconfirmations was carried out by paired t-testsperformed on the differences between the expected andblind mean hedonic ratings and bitterness and pungencymean intensity ratings. In the same way a paired t-testwas carried out between actual and blind mean ratingsas well as between actual and expected mean ratings inorder to study if an assimilation effect occurred and

what its extent might be.Two-way ANOVA and Fisher least significant differ-

ence multiple comparison test were performed to revealsignificant differences amongst the oil samples in terms

of actual liking, ‘‘typicality’’ response, as well as blindbitterness and pungency intensity, assuming subjectsand oils as factors, and in terms of expected liking andexpected bitterness and pungency intensity, assumingsubjects and information as factors. A two-way analysisof variance, assuming subjects and attributes as factors,

was also performed on the appropriateness ratings inorder to reveal significant differences between proposedsensory attributes.

Finally, Pearson correlation coefficients were calcu-lated between the mean intensity scores obtained fromconsumer and trained panels for both bitterness andpungency attributes in order to test the agreement of the consumer panel data with the trained panel.

3. Results

3.1. Blind evaluation and hedonic expectation

created by the information about the origin of the

experimental olive oils

Blind and expected mean liking scores and their stan-dard errors are reported in Table 3. The two-way anal-ysis of variance (ANOVA), carried out on the blindhedonic ratings of the six experimental oils, showed thatthe oils were not significantly different in terms of blindliking ( p > 0.05). Similarly the two-way analysis of variance revealed that the hedonic expectation ratingsobtained after examination of the three informationforms about the origin of the oils were not significantly

different ( p 0.05). These results were not unexpectedsince the consumers recruited in this study were selectedon the basis of their familiarity and use of these typicalolive oils.

Table 3Expectation effect on the oils acceptability

Product Ratings E B A B A E

B E A M p M p M p

A1 48.12 58.76 55.26 10.65 0.004 7.15 0.02 3.50 n.s.(2.74) (2.06) (2.51) Disconfirmation Assimilation

A2 55.62 58.76 58.17 3.15 n.s. 2.55 n.s.(3.01) (2.06) (2.36)

B1 51.85 57.70 52.70 5.85 n.s. 0.85 n.s.(3.49) (2.47) (3.04)

B2 47.18 57.70 57.41 10.53 0.03 10.23 0.02 0.29 n.s.(3.95) (2.47) (2.82) Disconfirmation Assimilation

C1 52.38 61.17 55.20 8.79 0.02 2.82 n.s.(3.03) (2.76) (2.81) Disconfirmation

C2 57.73 61.17 55.08 3.44 n.s. 3.61 n.s.(3.28) (2.76) (2.85)

E = Expected acceptability mean scores; B = blind acceptability mean scores (baseline); A = actual acceptability mean scores (with information);

M = mean; standard error in parentheses.



6/10

3.2. Effect of information about the origin on actual

liking of the experimental olive oils

Table 3 presents expected and actual liking (R) meanratings of the six experimental oils and the results fromthe paired t-test. A significant difference ( p 6 0.05)

shows that disconfirmation occurred. In particular re-sults from the oil A1 carrying the information ‘‘oil fromCoratina of Vulture area’’ reveal that the expected meanratings were significantly higher (t33 = 3.09, p = 0.004)than the blind score. This significant difference revealsthat a negative disconfirmation occurred. On the con-trary no disconfirmation was observed for the oil A2carrying the same information and for the oil B1 pre-sented as ‘‘oil from Ogliarola of the Bradano area’’whereas for the oil B2, carrying the same informationas B1, a negative disconfirmation (t33 = 2.28, p = 0.03)occurred. Finally for the two oils presented as ‘‘oil fromMaiatica of the Ferrandina area’’ a negative disconfir-

mation (t33 = 2.34, p = 0.02) was generated for oil C1while no disconfirmation was found for oil C2.

The significance of the differences between the actualliking of the product (R) and the baseline (B ) calculatedby a paired t-test allowed us to evaluate the effect of theresulting disconfirmation (Siret & Issanchou, 2000). Theresults are shown in Table 3. A significant difference( p 6 0.05) reveals an effect of information on hedonicscores. Amongst the conditions that generated hedonicdisconfirmation, oil A1 presented an assimilation effect(t33 = 2.35; p = 0.02) associated to the negative discon-firmation. Furthermore the study of the significance of

the differences between the actual (R) and the expected(E ) liking of the product allowed us to evaluate if theassimilation was complete or not (Siret & Issanchou,2000). Thus, as reported in Table 3, for the oil A1 theoccurring assimilation effect was total ( p > 0.05). Theoil B2 also showed an assimilation effect (t33 = 2.53, p = 0.02) associated to a negative disconfirmation andthis assimilation resulted complete too ( p 0.05).

For the oil C1 assimilation was not significant( p = 0.38). Similar results, following both positive andnegative disconfirmation, have been already reportedin previous works (Caporale & Monteleone, 2004;Lange et al., 1999; Siret & Issanchou, 2000). Althoughno clear interpretation of the phenomenon has beengiven, this result could be partly explained by a smallerand less significant disconfirmation (see Table 3). It ispossible that this explanation is not the only possibleone. In any case, the outcome of these observations doesnot allow the formulation of specific hypotheses.

Results from this study showed that when these typ-ical oils, which present the same hedonic expectations,were tasted a significant disconfirmation occurred forthree of the six products and these disconfirmationsproved to be negative. The different origin specified inthe information did not affect the disconfirmation occur-

rence. In fact oils with the same origin (i.e. Coratina,etc.) may or may not lead to disconfirmation. Resultsfrom this study indicate that identical expectations wereto some extent confirmed or disconfirmed sometimesgenerating assimilation.

3.3. Study of the typicality of the experimental oils

In order to further investigate the reason for thesedisconfirmations, ‘‘typicality’’ response was studied onthe six typical oils.

Results showed a significant effect (F 2,27 = 8.35; p = 0.001) of the factor ‘‘oil’’. ‘‘Typicality’’ mean ratingsand their standard errors are reported in Table 4 andshowed that the sample A2 ‘‘Coratina of the Vulturearea oil’’ presented the highest ‘‘typicality’’ ratings. Re-sults from the ANOVA indicate that subjects perceivedsome of the experimental oils to be more typical thanothers and these differences were not affected by the

origin of the oils. These results were compared to theresults of the two-way ANOVA model conducted onthe actual hedonic ratings which showed that the factor‘‘product’’ had no significant effect ( p > 0.05). Thus, A1and A2 oils differed ( p = 0.02) in terms of ‘‘typicality’’even though they are equally pleasant. These results al-lowed us to hypothesize that the ‘‘typicality’’ responsediffers from the hedonic response since familiar consum-ers rated the ‘‘typicality’’ response in relation to specificsensory expectations.

3.4. Study of the appropriateness of sensory

descriptors of typical extra virgin olive oils

This stage was carried out in order to select the mostappropriate attributes for describing the sensory proper-ties of the typical oils used in the study.

Results from the two-way analysis of varianceshowed a significant effect of the factor attribute(F 1,98 = 10.34, p = 0.001). Mean appropriateness ratingsand their standard errors are reported in Table 5 andranged from 3.03 (astringency) to 5.81 (pungency) onthe 7-point scale. Pungency and bitterness attributemean intensity ratings were the highest. The consumerpanel rated these attributes as appropriate sensory

Table 4Typicality mean ratings of the six products

Products Typicality

A1 61.41b (2.66)A2 70.62a (2.38)B1 58.29b (2.25)B2 56.44b,c (3.09)C1 51.09c (2.85)C2 61.70b (3.29)

Means with a same letter are not significantly different; Standard errorin parentheses.



7/10

descriptors of the presented typical extra virgin oliveoils. This is not surprising since, in general, consumersfind it relatively easy to identify and to describe thesesensory properties (Prescott, 1999). Furthermore, previ-

ous studies have shown that the intensities of bitternessand pungency descriptors characterise the oils and varygreatly (Bertuccioli, 1994; Monteleone, Caporale,Carlucci, & Bertuccioli, 1996). Mean intensity ratingsfor aroma descriptors ranged from 3.88 to 4.97. Thus,on the all, these attributes were only slightly appropri-ate. This evidence is probably due to the well known dif-ficulty of consumers in describing the sensory propertiesof food products (Issanchou, 2004; Lawless & Hey-mann, 1998). Pungency and bitterness attributes wereselected on the basis of these results.

3.5. Bitterness and pungency: blind evaluation and expectation created by the information about the

origin of the experimental oils

In order to study the effect of information relating toorigin on bitterness and pungency perceptions of exper-imental oils a blind evaluation of the intensity of theseattributes was carried out.

Mean intensity ratings of bitterness and pungency forthe six experimental oils as obtained by both consumerand trained panels are reported in Table 6.

Results of the two-way analysis of variance (Table 6)showed that the factor oils had a significant effect on both

bitterness and pungency. The F -value, associated to theoil factor for bitterness was higher than the F -value com-puted for pungency, indicating that samples were betterdiscriminated in relation to bitterness than pungency.

The relationships between the mean intensity scoresfor both attributes, which were obtained from consum-

ers and the trained panel were investigated. Bitternessand pungency mean intensity ratings from the consumerpanel were significantly correlated to the trained paneldata (rbitterness = 0.89, p = 0.01; rpungency = 0.81, p =0.04). The correlation coefficient values derived fromthe studied relationships indicate that consumer datatended to be consistent with the data obtained fromthe trained panel.

Results of the two-way analysis of variance indepen-dently computed on the expected bitterness and pun-gency ratings for the three proposed origins, showedthat information about cultivar significantly affected bit-terness and pungency expectations (bitterness: F 3,14 =

29.34, p < 0.001; pungency: F 3,14 = 24.98, p < 0.001).The results from the Fishers least-significant-differencetest showed that the expected bitterness and pungencymean ratings for ‘‘Coratina’’ oil are significantly higher( p < 0.001) than those computed for ‘‘Ogliarola’’ and‘‘Maiatica’’ oils. No significant differences ( p 0.05)were found between ‘‘Ogliarola’’ and ‘‘Maiatica’’ in theexpected mean ratings for both attributes. Results seemto indicate that bitterness and pungency were expectedto contribute to the sensory characterization of ‘‘Cora-tina’’ oil. On the other hand several studies showed thatthe sensory profile of ‘‘Coratina’’ oils is characterized by

a strong intensity of bitterness and pungency because of their phenol content (Tsimidou, 1998).

Due to the lack of clearly evident sensory expecta-tions for ‘‘Ogliarola’’ and ‘‘Maiatica’’ oils, we selectedonly the ‘‘Coratina’’ oils for the purpose of studyingthe effect of information about origin on sensoryexpectations.

3.6. Study of the effect of information about the

origin of oil on the perceived bitterness and pungency

In order to study the effect of information regardingorigin on the actual perceived intensity of bitterness

Table 5Mean appropriateness ratings of nine sensory attributes

Attribute Appropriateness

Apple 3.88c (0.29)Cut grass 4.97b (0.22)Almond 4.03c (0.27)Artichoke 4.34b,c (0.32)

Green olive 4.88b (0.35)Tomato 4.94b (0.30)Pungency 5.81a (0.26)Astringency 3.03d (0.31)Bitterness 5.76a (0.26)

Means with a same letter are not significantly different; standard errorin parentheses.

Table 6Blind mean intensity ratings of bitterness and pungency from consumer and trained panels

Mean ratings F sample p LSD

A1 A2 B1 B2 C1 C2

Consumer panel

Bitterness 47.44b 40.23b 45.91b 64.79a 31.70c 45.35b 13.63 0.000 8.18Pungency 44.23a,b 42.67b 46.32a,b 53.79a 31.44c 43.23b 5.70 0.000 8.38

Trained panel

Bitterness 5.57a 3.83b,c 4.50b 6.10a 2.77d 3.70c 22.38 0.000 0.73Pungency 5.93a,b 4.03c 5.57b 6.53a 3.40c 3.70c 15.58 0.000 0.93

Means with a same letter are not significantly different.



8/10

and pungency in ‘‘Coratina’’ oils (A1 and A2), differ-ences between expected and blind mean ratings and dif-ferences between actual and blind mean ratings of bothbitterness and pungency were calculated (Table 7).

In A1 oil the significant difference (t33 = 4.17, p = 0.000) between the expected and blind bitterness

mean intensity ratings revealed that a negative disconfir-mation occurred. Similarly the significant differencebetween actual and blind bitterness mean ratings(t33 = 2.35, p = 0.025) indicated that an assimilation ef-fect was generated. The study of the significance of thedifference between actual and expected bitterness meanintensity ratings showed that this assimilation wasincomplete (t33 = 2.54, p = 0.015). In the same waythe difference between expected and blind pungencymean intensity ratings proved to be significant (t33 =4.92, p = 0.000) thus revealing a negative disconfirma-tion. Furthermore, this disconfirmation generated anassimilation effect (t33 = 2.37, p = 0.02) which was also

incomplete (t33 = 2.15, p = 0.03). This result suggeststhat the Coratina Oil ‘‘A1’’ did not seem to correspondto expectations in terms of perceived bitterness and pun-gency intensity and this discrepancy induced consumersto assimilate towards their sensory expectations albeitnot completely.

Results from the A2 oil showed that expected meanintensity ratings for both bitterness and pungency attri-butes were higher (respectively t33 = 5.98, p = 0.000 andt33 = 5.21, p = 0.000) than the baseline indicating thatnegative disconfirmations occurred. Furthermore thesignificance of the (R – B ) and (R – E ) bitterness and pun-

gency mean intensity ratings (respectively t33 = 7.45, p = 0.000; t33 = 3.42, p = 0.002) indicated that assimila-tions occurred and that they were complete ( p > 0.05).The effect of the information about the oil s origin onthe perceived bitterness and pungency is reported inFigs. 1 and 2.

Results obtained from the two ‘‘Coratina’’ oils (A1and A2) are very similar, but the assimilation effects ob-served in the A2 oil were complete. This means that theimpact of the information about the origin on the per-ceived intensity of bitterness and pungency was strongerin the A2 oil than in the A1 oil.

4. Discussion

Many researchers have studied how extrinsic factorsinteract with intrinsic characteristics in the overall eval-uation of a product but these studies only concerned he-donic measurements. Different models were considered(Anderson, 1973) to describe how a difference betweenexpected and blind evaluation influences product evalu-ation and most of these studies revealed assimilationeffects (Caporale & Monteleone, 2004; Cardello & Saw-yer, 1992; Deliza, 1996; Lange et al., 1999; Siret & T

a b l e 7

E x p e c t a t i o n e ff e c t o n t h e p e r c e i v e d b i t t e r n e s s a n d p u n g e n c y o f t h e C o r a t i n a o i l s

A t t r i b u t e

R a t i n g s

E A 1

B A 1

A A 1

B A 1

A A 1

E A 1

E A 2

B A 2

A A 2

B A 2

A A 2

E A 2

B A 1

B A 2

E

A A 1

A A 2

M

p

M

p

M

p

M

p

M

p

M

p

B i t t e r n e s s

4 8 . 6

1

4 0 . 6

4

6 5 . 2 0

5 6 . 5

8

6 5 . 9

4

1 6 . 5

9

0 . 0

0 0

7 . 9

7

0 . 0

2 5

8 . 6

2

0 . 0

1 5

2 4 . 5

6

0 . 0

0 0

2 5 . 3

0

0 . 0 0

0

0 . 7

3

n . s .

( 3 . 4

8 )

( 2 . 8

3 )

( 3 . 4

8 )

( 2 . 7

2 )

( 3 . 2

8 )

D i s c o n fi r m a t i o n

A s s i m i l a t i o n



P u n g e n c y

4 5 . 1

1

4 1 . 7

9

6 4 . 2 3

5 4 . 2

0

5 7 . 7

9

1 9 . 1

2

0 . 0

0 0

9 . 0

9

0 . 0

2

1 0 . 0

3

0 . 0

3

2 2 . 4

4

0 . 0

0 0

1 6 . 0

0

0 . 0 0

2

6 . 4

4

n . s .

( 3 . 3

9 )

( 3 . 6

3 )

( 3 . 5

1 )

( 3 . 0

5 )

( 3 . 1

4 )





E =

E x p e c t e d m e a n s c o r e s ; B = b l i n d a c c

e p t a b i l i t y m e a n s c o r e s ( b a s e l i n e ) ; A = a c t u a

l a c c e p t a b i l i t y m e a n s c o r e s ( w i t h i n f o r m a t i o n ) ; M = m e a n ; s t a n d a r d e r r o r i n p a r e n t h e

s e s .



9/10

Issanchou, 2000). In the present study both hedonic and‘‘typicality’’ measurements were carried out in order tostudy how their corresponding responses can be affectedby information about the origin of the extra virgin oliveoils. Authors are conscious that the restricted number of subjects, due to the restrictive criteria used in the selec-tion of consumers, might have caused some possible lim-itations to the study. Anyway, results obtained by thehedonic measurements confirm the findings of previousstudies (Siret & Issanchou, 2000; Tuorila, Meiselman,Cardello, & Lesher, 1998) which revealed that the infor-mation evoking the origin affects product acceptabilityand creates a favourable hedonic expectation by familiarconsumers (Caporale & Monteleone, 2001).

In our study information about the origin led in cer-tain cases to a negative disconfirmation which either didor did not generate an assimilation effect for overall lik-ing. In any case, when consumers had external informa-tion, no significant differences appeared between the oilsin terms of hedonic ratings.

On the contrary, the results obtained from the ‘‘typi-cality’’ response indicated that the experimental oils haddifferent levels of ‘‘typicality’’. Information on origin didnot have the same effect on different consumer responsessuch as liking or typicality.

The significant differences found in the typicalityscores for the oils under examination raise the problemof defining the extent to which sensory properties influ-ence this result. If their influence is significant, theninformation on origin could generate expectationsregarding specific sensory properties, in consumers

who are familiar with the product.The results have highlighted the fact that, eventhough consumers may be familiar with the product,they tended to consider only those attributes which arerelatively easy to recognise (e.g. bitterness and pun-gency) as being appropriate for the description of thesensory properties of the presented oils.

The reliability of the consumers sensory responseswas supported by the consistency of consumer data withthe data obtained from the trained panel.

No correlations were found between typicality scoresand bitterness, or pungency scores (rbitterness = 0.001, p = 0.99; rpungency = 0.246, p = 0.64) obtained in the

blind condition. This finding would seem to show thatthe relationship between typicality of the presented oilsand these attributes was not univocal (i.e. the greaterthe intensity of bitterness perceived the greater the typ-icality) but rather that it was specific (i.e. the same per-ceived intensity of bitterness may be associated withdifferent perceptions of typicality for oils of different ori-gins). On the basis of these results we cannot exclude thepossibility that there may be other attributes, besidesbitterness and pungency, which are important descrip-tors of other typical oils. This hypothesis could be thefocus of a study on a large number of oils.

In spite of its limitations, this study has, nevertheless,made it possible to evaluate the effect of informationabout origin on expectations in respect of specific sen-sory properties of typical oils. Consumers assimilatedthe perception of bitterness and pungency to their expec-tations as a consequence of negative disconfirmation.However, complete assimilation to expectations oc-curred in only one of the two oils presented. As alreadystated, the possible consequences of incomplete assimila-tion towards hedonic expectations have been widely de-bated by many authors. Very little has been said aboutthe consequences of incomplete assimilation towardsexpectations concerning the sensory properties of prod-ucts. The data at our disposal does not permit us tomake detailed hypotheses. However, the results of someexperiments ought to be noted. The effect of informationabout origin on the perceived bitterness and pungencyof the Coratina oils indicated that sensory disconfirma-tions leading to complete assimilation in both bitternessand pungency perception were associated to higher‘‘typicality’’ ratings. No analogous correspondence be-tween complete assimilation and hedonic rating wasfound. If the typicality response has weight in the con-sumers evaluation of the perceived quality of a typicalproduct then it cannot be excluded that under repeated

0

10

20

30

40

50

60

70

80

B i t t e r n

e s s m e a n i n t e n s i t y

Oil A1 Oil A2

blind

expected

actual

Fig. 1. Effect of expectancy disconfirmation for the Coratina oilsperceived bitterness.

0

10

20

30

40

50

60

70

80

P u n g e n c y m e a n i n t e n s i t y

blind

expected

actual

Oil A1 Oil A2

Fig. 2. Effect of expectancy disconfirmation for the Coratina oilsperceived pungency.



10/10

tasting, sensory disconfirmations which do not assimi-late totally, can determine a loss of product reputationthrough lack of reliability.

5. Conclusions

Results from this research confirmed that infor-mation evoking the origin of food product create afavourable hedonic expectation in familiar consumers.Interestingly, information on origin did not have thesame effect on different consumer responses such as lik-ing or typicality. Although, it was shown that informa-tion about origin affects the expectations with regardsto specific sensory attributes in familiar consumers, themethodological approaches to studies on sensory prop-erty expectations need perfecting. Furthermore, datafrom the present research suggests that further studies

are needed to verify if, under repeated tasting, it is pos-sible that sensory disconfirmations which do not assim-ilate totally, can determine a loss of product reputation.

References

Anderson, R. E. (1973). Consumer dissatisfaction: the effect of disconfirmed expectancy on perceived product performance.Journal of Marketing Research, 10, 38–44.

Bertuccioli, M. (1994). A study of sensory and nutritional quality of virgin olive oil in relation to variety, ripeness and extractiontechnology. Overview of three year study and conclusion. Grasas y

Aceites, 45(1–2), 55–59.Bilkey, W. J., & Nes, E. (1982). Country-of-origin effects on productevaluations. Journal of International Business Studies, 13, 89–99.

Caporale, G., & Monteleone, E. (2001). Effect of expectations inducedby information on origin and its guarantee on the acceptability of atraditional food: olive oil. Sciences des Aliments, 21, 243–254.

Caporale, G., & Monteleone, E. (2004). Influence of informationabout manufacturing process on beer acceptability. Food Qualityand Preference, 15, 271–278.

Cardello, A. V. (1994). Consumer expectations and their role in foodacceptance. In H. J. H. MacFie & D. M. H. Thompson (Eds.),Measurement of food preferences (pp. 253–297). London: BlackieAcademic Press.

Cardello, A. V., & Sawyer, F. M. (1992). Effects of disconfirmedconsumer expectations on food acceptability. Journal of Sensory

Studies, 7 , 253–277.Deliza, R. (1996). The effects of expectation on sensory perception and

acceptance. Unpublished PhD thesis, University of Reading, UK.Deliza, R., & MacFie, H. J. H. (1996). The generation of sensory

expectation by external cues and its effect on sensory perceptionand hedonic ratings: a review. Journal of Sensory Studies, 7 ,253–277.

Deliza, R., MacFie, H., & Hedderley, D. (2003). Use of computergenerated images and conjoint analysis to investigate sensoryexpectations. Journal of Sensory Studies, 18(6), 465–486.

Dichter, E. (1962). The world customer. Harvard Business Review, 40,113–122.

Goering, P. A. (1985). Effects of product trial on consumer expecta-tions, demand, and prices. Journal of Consumer Research, 12,74–82.

Issanchou, S. (1996). Consumer expectations and perceptions of meatand meat product quality. Meat Science, 43, S5–S19.

Issanchou, S. (2004). Sensory and hedonic consumer expectationstowards typical food products. In European Conference on SensoryScience of Food and Beverages, Florence, Italy, 26–29 September.

Johansson, L., Haglund, Å., Berglund, L., Lea, P., & Risvik, E. (1999).Preference for tomatoes, affect by sensory attributes and informa-tion about growth conditions. Food Quality and Preference, 10,289–298.

Kähkönen, P., & Tuorila, H. (1996). How information enhancesacceptability of a low-fat spread. Food Quality and Preference, 7 ,87–94.

Kähkönen, P., & Tuorila, H. (1998). Effect of reduced-fat informationon expected and actual hedonic and sensory rating of sausage.

Appetite, 30, 13–23.Lange, C., Rousseau, F., & Issanchou, S. (1999). Expectation, liking

and purchase the effect of order behaviour under economicalconstraint. Food Quality and Preference, 10, 31–39.

Lawless, H. T., & Heymann, H. (1998). The Central Dogma—Analyticvs. Hedonic Tests. In Sensory evaluation of food principles and practices (pp. 13–16). Kluwer Academic Publishers Group.

MacFie, H. J. H., Bratchell, N., Greenhoff, K., & Vallis, L. V. (1989).Designs to balance the effect of order of presentation and first ordercarry-over effects in hall tests. Journal of Sensory Studies, 4,129–148.

Mojet, J., & de Jong, S. (1994). The sensory wheel of virgin olive oil.Grasas y Aceites, 45, 42–47.

Monteleone, E., Caporale, G., Carlucci, A., & Bertuccioli, M. (1996).Prediction of virgin olive oil sensory profile. Industrie Alimentari,35, 1066–1072.

Peterson, R. A., & Jolibert, A. J. P. (1995). A meta-analysis of country-of-origin effects. Journal of International Business Studies, 26 ,883–900.

Prescott, J. (1999). Flavour as a psychological construct: implications

for perceiving and measuring the sensory qualities of foods. Food Quality and Preference, 10, 349–356.Prescott, J., & Young, A. (2002). Does information about MSG

(monosodium glutamate) content influence consumer rating of soups with and without added MSG? Appetite, 39, 25–33.

Siret, F., & Issanchou, S. (2000). Traditional process: influence onsensory properties and on consumers expectation and liking.Application to ‘‘pâte de campagne’’. Food Quality and Preference,11, 217–228.

Steenkamp, J. B. E. M. (1990). Conceptual model of the qualityperception process. Journal of Business Research, 21, 309–333.

Tuorila, H., Cardello, A. V., & Lesher, L. L. (1994). Antecedents andconsequences of expectations related to fat-free and regular-fatfoods. Appetite, 23, 247–263.

Tuorila, H., Meiselman, H. L., Cardello, A. V., & Lesher, L. L. (1998).

Effect of expectations and the definition of product category on theacceptance of unfamiliar foods. Food Quality and Preference, 9 ,421–430.

Tsimidou, M. (1998). Polyphenols and quality of virgin olive oil inretrospect. Italian Journal of Food Science, 10(2), 99–116.

Van der Lans, I. A., van Ittersum, K., De Cicco, A., & Loseby, M.(2001). The role of the region of origin and EU certificates of originin consumer evaluation of food products. European Review of Agricultural Economics, 28(4), 451–477.

Verlegh, P. W. J., & Steenkamp, J. B. E. M. (1999). A review andmeta-analysis of country-of-origin research. Journal of EconomicPsychology, 20, 521–546.


Caporale Et Al., 2006. Consumer Expectations for Sensory Properties in Virgin Olive Oils.

Documents

Transcript of Caporale Et Al., 2006. Consumer Expectations for Sensory Properties in Virgin Olive Oils.