- Email: [email protected]
Studying the influence of package shape and colour on consumer expectations of milk desserts using word association and conjoint analysis
Food Quality and Preference 21 (2010) 930–937
Contents lists available at ScienceDirect
Food Quality and Preference journal homepage: www.elsevier.com/locate/foodqual
Studying the influence of package shape and colour on consumer expectations of milk desserts using word association and conjoint analysis Gastón Ares a,*, Rosires Deliza b,c a Sección Evaluación Sensorial, Departamento de Ciencia y Tecnología de Alimentos, Facultad de Química, Universidad de la República (UdelaR), Gral. Flores 2124. C.P. 11800, Montevideo, Uruguay b EMBRAPA (Brazilian Agricultural Research Corporation) Labex Europe, Dijon, France c INRA, UMR CSGA, 17 rue Sully, F-21065 Dijon, France
a r t i c l e
i n f o
Article history: Received 30 August 2009 Received in revised form 19 January 2010 Accepted 8 March 2010 Available online 12 March 2010 Keywords: Word association Expectations Consumer studies Conjoint analysis Milk desserts Packaging
a b s t r a c t Food packaging plays a major role in attracting consumer attention and generating sensory and hedonic expectations; which could affect their product perception and purchase decisions. In the present study word association and conjoint analysis were used to study the influence of package shape and colour on consumer expectations of milk desserts. Six images of milk dessert packages with different colour and shape were presented to 105 consumers, who were asked to complete a word association task and to score their expected liking and willingness to purchase the desserts. Both package shape and colour affected consumers expected liking scores and their sensory expectations regarding the desserts. Consumers associations were mainly related to sensory characteristics. Both methodologies provided an interesting insight on the consumer’s expectations generated by the packages and could be useful in order to design packages which create appropriate expectations regarding the product. Ó 2010 Elsevier Ltd. All rights reserved.
1. Introduction Food package is the container that holds, protects, preserves and identifies the product, and which also facilitates its handling, storage and commercialization (Rodríguez Tarango, 2003). Packaging also plays a major role in attracting consumer attention and influencing consumer purchase decisions. In the context of current self-service food retailing, packaging provides food companies the last chance to persuade consumers to buy the product before brand selection (McDaniel & Baker, 1977). Therefore, all packaging elements have to be combined to attract the consumer when purchasing the product (McNeal & Ji, 2003). According to several authors, shape and colour are important features during package design (Ampuero & Vila, 2006; Hutchings, 2003; Marshall, Sutart, & Bell, 2006). Apart from influencing consumer purchase decision, food package may also create expectations in the consumer (Deliza, MacFie, & Hedderley, 2003; Lange, Issanchou, & Combris, 2000; Rodríguez Tarango, 2003). If the hedonic expectations created by the package are high, the consumer may be interested in the product and choose to buy it. However, sensory and hedonic expectations could also affect consumer response when tasting the product (Tuorila,
* Corresponding author. Tel.: +5982 9245735; fax: +5982 9241906. E-mail address: [email protected] (G. Ares). 0950-3293/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodqual.2010.03.006
Meiselman, Cardello, & Lesher, 1998). When the product is tasted, the expected sensory characteristics of the product are compared with the products’ real characteristics, leading to confirmation or disconfirmation (Deliza & MacFie, 1996). If the consumer confirms his (her) expected sensory characteristics he (she) would likely repeat product purchase. However, if the expected sensory characteristics are not perceived, the consumer will probably not buy the product again (Deliza & MacFie, 1996). Therefore, manufacturers should use food package to attract consumers’ attention in order to increase their interest in buying the product; but also to generate sensory and hedonic expectations that match the products’ real characteristics. Although food companies usually invest large amounts of money on package design there are not many published studies about the influence of package characteristics on consumer expectations of food products (Deliza & MacFie, 1996; Lange et al., 2000; Moskowitz, Reiner, Lawlor, & Deliza, 2009; Murray & Delahunty, 2000). In this context, it is very important to rely on methodologies that allow a precise identification of consumer expectations generated by packages. Word association is a qualitative methodology widely used in psychology and sociology (Doise, Clémence, & Lorenzi-Cioldi, 1993; Schmitt, 1998). This methodology is based on the assumption that giving a stimulus to respondents and asking them to write down the associations that come to their minds gives relatively unrestricted access to mental representations of the stimulus.
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
When dealing with food products, the associations that first come to the respondents’ mind may be the most relevant for consumers’ decisions related to product purchase (Roininen, Arvola, & Lähteenmäki, 2006). The ideas expressed within a word association task are spontaneously elicited and might be subjected to fewer constraints than that typically imposed in interviews or closed questionnaires (Wagner, Valencia, & Elejabarrieta, 1996). For these reasons, this technique could be an interesting tool for exploring consumers’ perception of food products. In this task, consumers’ elicited terms about a food product could be related to their sensory and hedonic expectations. Conjoint analysis is a useful tool to investigate the effect of different package features on consumer purchase intention (Deliza, Rosenthal, & Silva, 2003). This methodology could be used to estimate the relative importance of different package attributes on consumer perception of food products. The aims of the present work were to: (a) evaluate the applicability of word association to study consumer associations about milk dessert packages as a mean to understand their expectations, and (b) study the influence of package shape and colour on consumer expectations of milk desserts. 2. Materials and methods
931
several groups of consumers, including children and elderly people. Besides, there is increasing marketing activity regarding milk desserts in Uruguay, as most dairy companies have launched new low-fat and low-calorie desserts. Milk dessert packages were designed using two categorical factors: shape and colour. These package features were selected considering previous studies carried out with Uruguayan consumers using free listing and word association (Ares & Deliza, 2010), and the fact that they are responsible for the highest variability of packages available in Uruguayan market. Two shapes (round and square) and three colours (white, black and yellow) were considered in the study. Thus, six images of milk packages were created following a full factorial experimental design. They were printed in glossy paper, and coated with contact paper yielding six different cards. The milk dessert packages images were obtained from commercial milk dessert packages and retouched using Adobe Photoshop 7.0 (Adobe Systems Incorporated, 2002). Two examples of the cards used in the study are shown in Fig. 1. 2.3. Consumer evaluation The six cards were presented to participants numbered with three-digit random codes, and following a balanced order for each participant (MacFie, Bratchell, Greenhoff, & Vallis, 1989).
2.1. Participants The study was conducted in the city of Montevideo (Uruguay). One-hundred and five people participated in the study; 39% of which were males and 61% females. Participants ranged in age from 18 to 77 years old (mean 33.7 years old, standard deviation 14.9 years old); being 63% of the participants under 35 years old and the other 37% of the participants were 35 or more years old. All participants consumed milk desserts at least once a week, and were randomly recruited at shopping areas, universities campus and public places. The studied consumer sample can be regarded as a convenience sample which is usually considered in exploratory studies when the main interest is to get an approximation to a research subject (Guerrero et al., 2009).
2.3.1. Word association task Consumers were asked to evaluate each of the six cards with the packages one at a time, and to write down the first four images, associations, thoughts or feelings that came to their minds when thinking of the dessert inside the packages. 2.3.2. Conjoint analysis task After completing the word association task, participants were also asked to evaluate their expected liking of the desserts using a 9-point hedonic scale labelled on the left with ‘dislike very much’ and on the right with ‘like very much’, and their willingness to purchase the desserts using a 9-point structured scale labelled on the left with ‘I would definitively not buy it’ and on the right with ‘I would definitively buy it’.
2.2. Stimuli
2.4. Data analysis
A milk dessert was selected as base product for the present study. This selection was made considering that these products are widely consumed worldwide, and particularly in Uruguay, by
2.4.1. Conjoint analysis Analysis of variance (ANOVA) was performed on data from expected liking and willingness to purchase. The ANOVA method
Fig. 1. Two examples of the images used in the study (a) round yellow package and (b) square black package.
932
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
considered in the present study was the following (Naes, Kubberod, & Sivertsen, 2001): Y = main effect for package variables (colour and shape) + main random effect for consumer + interactions between package variables + interactions between consumer and package variables + random error. When the effects were significant, honestly significant differences were calculated using Tukey’s test. Differences were considered significant when p < 0.05. All statistical analyses were performed using GenStat for Windows Discovery Edition 2 (VSN International Ltd., Hempstead, UK). 2.4.2. Qualitative analysis of the elicited words The elicited associations were qualitatively analyzed. First, a search for recurrent terms within each package was performed. Terms with similar meaning were grouped into different categories within each package. This classification was performed independently by three researchers considering personal interpretation of the meaning of the words and word synonymy as determined by a Spanish dictionary. The three researchers had previous experience in analyzing qualitative data from open-ended-questions and word association tasks. After individually evaluating the data, a meeting of the researchers was undertaken in order to check the agreement between their classifications. The final categories and their names were determined by consensus between the three researchers considering their three independent classifications and discussion between them. This triangulation technique has been used by other authors dealing with qualitative techniques (Guerrero et al., 2009; Modell, 2005; Wadsworth, 2000). Categories comprising terms mentioned by more than 10% of participants were considered. Frequencies in each category were determined by counting the number of participants that used those words to describe the concept. Then, associations from the different packages with similar meaning were merged. This task was carried out by the three researchers that performed the classification of terms. Frequencies of word counting in each category were calculated for each package. Chi-square was calculated for evaluating differences in consumers’ perception of the milk dessert packages. 2.4.3. Multiple Factor Analysis Multiple Factor Analysis (MFA) is a factor analysis method that deals with data sets composed of both quantitative variables and frequency tables, and analyzes observations described by different groups of variables (Bécue-Bertaut & Pagès, 2008; Bécue-Bertaut, Álvarez-Esteban, & Pagès, 2008). In the present study, three groups of variables were considered: frequency of mention of terms elicited in the word association task, expected liking and willingness to purchase scores. Therefore, MFA was performed to provide an integrated representation of the packages and of the relationships between consumers’ associations, and scores for expected liking and willingness to purchase. MFA analysis was performed on a table juxtaposing the frequency table of consumer associations and consumer scores for expected liking and willingness to purchase, using FactoMineR (Husson, Josse, Lê, & Mazet, 2007; Lê, Josse, & Husson, 2008) in R language (R Development Core Team, 2007). 3. Results 3.1. Influence of shape and colour on consumer expected liking and willingness to purchase Consumer scores for expected liking of the desserts ranged from 4.8 to 6.7, whereas scores for willingness to purchase ranged from 4.5 to 6.6. According to ANOVA consumers showed highly significant different degrees of expected liking and willingness to pur-
Table 1 ANOVA results for expected liking and willingness to purchase scores. Effect Shape Colour Shape colour Consumer shape Consumer colour *
Expected liking *
3.8 21.9*** 0.5ns 0.9ns 1.3ns
Willingness to purchase 1.6ns 22.0*** 0.9ns 0.5ns 0.8ns
Significant effect at p < 0.05. Significant effect at p < 0.001. No significant effect (p > 0.05).
***
ns
chase of the desserts, suggesting that consumers perceived packages differently. Furthermore, ANOVA revealed that the main effect of the conjoint variables package shape and colour had a highly significant effect on consumer expected liking, as shown in Table 1. However, for willingness to purchase only package colour had a significant effect. The interaction between the conjoint variables package shape colour was not significant for consumer expected liking and willingness to purchase scores; which indicates that consumers independently evaluated the shape and colour of the packages. The interactions between package variables and consumer were also not significant for both expected liking and willingness to purchase scores. Mean effects part-worth utilities for expected liking and willingness to purchase were calculated and are shown in Table 2. Colour had higher part-worth utilities than shape, indicating that the former package feature was more important for consumers. For expected liking the relative importance of colour was 82.5%, whereas for willingness to purchase it was 88.4%. Differences were found in the utilities of colour for expected liking and willingness to purchase. As shown in Table 2, expected liking scores were able to discriminate between all levels of the evaluated variables. Round shape showed a highly significant higher utility than square for expected liking, but no significant differences were found between these features for willingness to purchase. Regarding package colour, yellow showed the highest utility for expected liking, followed by white and finally black packages; whereas no significant differences (p > 0.05) were found between the willingness to purchase of black and white packages. 3.2. Word association 3.2.1. Consumer elicited terms in the word association task The elicited words were merged into 28 categories, corresponding to those mentioned by more than 10% of the participants, as explained in Section 2.4.2. Table 3 shows the frequencies in which each category was mentioned for each package. Consumer associations were related to sensory characteristics of the desserts,
Table 2 Conjoint analysis results (part-worth utilities and relative importance of each attribute) for expected liking and willingness to purchase scores. Attributes and levels
Expected liking
Willingness to purchase
Shape Round Square Relative importance
0.205a 0.205b 17.5%
0.145a 0.145a 11.6%
Colour Black White Yellow Relative importance
0.73c 0.23b 0.97a 82.5%
0.60b 0.50b 1.10a 88.4%
Values with different letters within the same column for the same attribute are significantly different (p < 0.05) according to Tukey’s test.
933
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937 Table 3 Number of mentions of terms for the six milk dessert packages considered in the word association task. Term*
Vanilla Chololate Creamy Delicious Sweet Thick Milky Soft Disgusting Small serving Low-calorie Tasteless Egg custard Adequate serving Runny Dulce de leche** Premium Yellow Interesting Plain Bitter Dark colour Fruity Childish Light colour Strong flavour Sour Caramel * **
Milk dessert package Round black
Round white
Round yellow
Square black
Square white
Square yellow
0 53 17 13 17 8 5 4 16 14 3 2 4 0 9 2 12 2 12 0 9 12 5 3 0 7 0 2
26 0 24 15 9 2 17 18 6 17 0 19 2 0 10 2 0 0 2 11 0 0 5 11 4 0 6 0
58 0 30 22 25 9 5 24 0 18 2 3 9 0 11 15 3 11 3 2 0 0 0 5 4 0 0 0
0 57 3 11 4 18 5 2 24 0 12 0 8 12 3 2 15 3 12 0 22 14 2 0 0 15 0 2
21 0 17 15 7 12 29 10 12 0 20 16 2 15 5 0 3 2 2 17 0 0 11 2 4 0 11 0
38 0 17 16 16 21 3 6 3 0 10 3 18 15 0 15 3 17 3 2 0 0 2 2 11 0 2 15
Only terms mentioned by more than 10% of the participants were considered. Dulce de leche is a kind of sweetened condensed milk, typical of Latin American countries such as Argentina, Brazil and Uruguay.
mainly flavour and texture attributes. As shown in Table 3, the most mentioned associations were vanilla, chocolate, creamy, and delicious; indicating the importance of packaging in generating sensory and hedonic expectations of milk desserts. Consumer associations were highly significantly different for the six evaluated packages (v2 = 1229, p < 0.001), suggesting that package shape and colour significantly affected consumer expectations of the desserts inside evaluated packages. Differences in consumer associations were found with package colour and shape, as shown in Table 3. Yellow packages were more associated with sweet vanilla or dulce de leche desserts; whereas black packages were associated with bitter, strong flavoured chocolate desserts regarded as disgusting or premium and interesting. Besides, white packages were associated with milky vanilla or plain desserts, which were considered tasteless. On the other hand, round packages tended to be more associated with runny, creamy and soft desserts; whereas square packages were associated with thick, low-calorie milk desserts. These results suggest that package shape and colour affected consumers’ sensory and hedonic expectations of the desserts. 3.2.2. Multiple Factor Analysis Multiple Factor Analysis (MFA) was used to study the relationships between the packages and consumer associations, as well as between consumer expectations and consumer expected liking and willingness to purchase. The first three dimensions of the MFA accounted for by 95.1% of the variance of the experimental data, representing 54.6%, 24.4%, and 16.1% of the variance, respectively. As shown in Table 4, the eigenvalue of the first dimension indicates that it can be considered an important direction in explaining the dispersion of both consumer scores and the frequency table of the terms elicited in the word association task (Bécue-Bertaut et al., 2008). Both the scores and the associations contributed in a balanced way to the inertia of the first dimension (52.7% and
Table 4 Eigenvalues and percentage of the variance of the experimental data explained by the first four dimensions of the Multiple Factor Analysis (MFA). Dimension from MFA
Eigenvalue
Percentage of variance (%)
Cumulative percentage of variance (%)
1 2 3 4
1.837 0.822 0.540 0.102
54.6 24.4 16.1 3.0
54.6 79.0 95.1 98.1
47.3%, respectively). On the contrary, the associations explained more than 95% of the inertia of the second and third dimensions, indicating that these dimensions were mainly explained by consumer associations of the packages and not by their scores. The first dimension of the MFA was positively correlated with expected liking and willingness to purchase scores, and with words related to the expected flavour of the desserts (such as sweet, Dulce de leche, and vanilla), and to a positive hedonic reaction (delicious), as shown in Fig. 2. Besides, it was negatively correlated to a category including terms related to a negative hedonic reaction (disgusting). The second dimension was positively correlated with words related to thickness and negatively with fruity, sour, milky flavour, plain, and tasteless. On the other hand, the third dimension was related to the serving size and to the category low-calorie. As shown in Fig. 2, expected liking and willingness to purchase scores were positively correlated with the category named delicious, and negatively to words such as disgusting. This indicates the concordance of both types of evaluations. Fig. 3 shows the representation of the packages in the MFA dimensions. The first and second dimensions mainly sorted the packages into three groups; which corresponded to the three evaluated colours. This is in agreement with the abovementioned
934
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
(a)
Dimension 2: 24.4%
1
0.8
Premium Bitter Interesting Dark colour Strong flavour Chocolate
Thick
Egg custard
0.6
Caramel
Yellow Dulce de leche
0.4
Disgusting
Willingness to purchase
Adequate serving 0.2
Sweet Expected liking
Low-calorie 0 -1.5
-1
-0.5
LIght colour 0
1Dimension
0.5
1: 54.6%1.5
Vanilla Delicious
-0.2
Small serving
-0.4
Creamy Soft
Thin
-0.6
Fruity
Childish Sour -0.8
Plain Tasteless
Milky flavour
-1
-1.2
(b)
1.2
Dimension 3: 16.1%
1
Adequate serving Low-calorie 0.8 Sour
Thick
0.6
Caramel LIght colour
Plain
Fruity Milky flavour
0.4
Egg custard Yellow
0.2 Tasteless
Dulce de leche
Dimension 1: 54.6% -1.5
0
Disgusting
-1
Premium
-0.5
0
Bitter
0.5
-0.2
Soft
Strong flavour Dark colour
Vanilla Willingness to purchase Expected liking 1 1.5 Delicious
Interesting
-0.4
Creamy Sweet
Childish
Chocolate -0.6
-0.8
Thin
Small serving
-1
(c)
1.2
Dimension 3: 16.1%
1
Adequate serving Low-calorie
0.8
Sour
Thick
LIght colour
0.6
Caramel Plain
Fruity
0.4
Milky flavour
Yellow
Tasteless
0.2
Vanilla
Dulce de leche Dimension 2: 24.4%
0 -1.2
-1
-0.8
Egg custard
-0.6
-0.4
-0.2
0
0.2
Delicious
-0.4
0.6
0.8
1
Bitter Premium Strong flavour
-0.2
Creamy Soft Childish
Disgusting 0.4
Sweet
Dark colour Interesting Chocolate
-0.6
Thin
Small serving
-0.8
-1
Fig. 2. Representation of the words and consumer scores for expected liking and willingness to try in the first three dimensions of the Multiple Factor Analysis.
higher relative importance of colour on consumer expected liking and willingness to purchase scores.
Therefore, the main differences between consumers’ associations regarding the packages were due to their different colour.
935
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
(a)
2
S-B
Dimension 1: 54.6%
Dimension 2: 24.4%
1
S-Y
R-B 0
-2.5
-1.5
-0.5
0.5
1.5
R-Y
2.5
-1
S-W
R-W
-2
(b)
1.5
Dimension 3: 16.1%
S-W
S-Y
0.5
Dimension 2: 24.4%
S-B -2.5
-1.5
-0.5
R-W
0.5
1.5
2.5
-0.5
R-Y R-B
-1.5
(c)
1.5
Dimension 3: 16.1%
S-W
S-Y
0.5
Dimension 1: 54.6%
S-B -2.5
-1.5
-0.5
0.5 -0.5
1.5
2.5
R-W R-Y
R-B
-1.5
Fig. 3. Representation of the packages in the first three dimensions of the Multiple Factor Analysis. Description of the packages: round black (RB), round yellow (RY), round white (RW), square black (SB), square yellow (SY) and square white (SW).
Yellow packages were located to the right of the first dimension; being associated with sweet, delicious, vanilla and dulce de leche desserts. Also, these packages showed the highest expected liking and willingness to purchase scores. On the other hand, white packages were located at mid-values for the first dimension and negative values of the second dimension; corresponding to plain, sour, tasteless, and fruity milk desserts. Meanwhile, black packages were located in the second quadrant of the first and second dimension; being mainly associated with bitter dark coloured, chocolate des-
serts regarded as disgusting, interesting and premium. Consumers mainly associated different package colour with different flavours; indicating that colour mainly generated sensory expectations related to the flavour of the dessert inside the package. As shown in Fig. 3, black packages were associated with contradictory terms such as interesting, premium and disgusting; which indicates heterogeneity in consumer attitude towards this package colour. According to the results of the present study, it seemed that a group of consumers rejected black packages, as they associated
936
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
them with disgusting desserts; whereas another consumer group expected interesting and premium desserts. Furthermore, in the representation of the second and third dimensions of the MFA packages were sorted according to their shape (c.f. Fig. 3). Square packages tended to be located at positive values of the second dimension, whereas round packages were located at negative values of this dimension. As shown in Table 3 and Fig. 3, round packages were associated with runny desserts, whereas square packages were associated with thick. This might indicate that package shape created sensory expectations regarding the texture of the desserts. Also, the size of the serving was perceived differently for round and square packages. Consumers considered the serving of a square package as adequate, whereas the serving of a round package was regarded as small. Furthermore, the package’s shape and colour affected the specific type of dessert consumers expected to find inside the packages. As shown in Table 3 and Fig. 3, consumers related yellow square packages with words such as thick, caramel, and egg custard. Meanwhile, yellow round packages were associated with creamy, runny and soft desserts. 4. Discussion 4.1. Influence of package shape and colour on consumers’ expectations, expected liking and willingness to purchase milk desserts Both colour and shape significantly affected consumers’ associations, expected liking and willingness to purchase. Consumer associations regarding package colour were mainly related to flavour; in agreement with previous studies (Hutchings, 2003; Lavin & Lawless, 1998; Marshall et al., 2006). Differences in expected liking scores due to package colour might be related to consumers’ hedonic reaction towards the expected flavour of the desserts. This could explain the fact that colour had a larger influence than shape in consumer expected liking and willingness to purchase scores. Consumers seemed to prefer packages that were associated with sweet, vanilla and dulce de leche flavoured milk desserts. On the other hand, differences in consumer associations due to differences in package shape were mainly related to sensory expectations related to texture characteristics (e.g. runny and thick) and to specific types of desserts (e.g. egg custard or low-calorie desserts) (c.f. Table 3 and Fig. 3). Apart from influencing expected flavour, package colour also affected texture expectations regarding the creaminess and softness of the desserts. As shown in Table 3, yellow round packages were more frequently associated with creamy and soft desserts than black or white ones. These results show the relevance of package characteristics, such as colour and shape, in creating sensory expectations on consumers, which could affect their product perception and acceptance. Besides, participants also associated certain package shapes and colours with specific products, such as egg custard or low-calorie desserts. Thus, during product and package development it would be important to study which sensory expectations packages are able to create in consumer’s mind. 4.2. Methodological issues The combination of word association and conjoint analysis provided interesting and valuable information regarding the influence of package shape and colour on consumer perception of milk desserts. The use of MFA allowed evaluating simultaneously consumer scores and free associations, providing a synthetic view of consumer’s perception of the packages.
Expected liking and willingness to purchase scores were useful to evaluate the influence of package shape and colour on consumer hedonic expectations and their purchase intention. However, both scores provided different results. This could also be related to the fact that price was not taken into account in the present study. Consumers did not take into account price when indicating their willingness to purchase the desserts despite the fact that this variable could have a large impact in consumers’ purchase decisions (Jaeger, 2006). Furthermore, word association task provided an insight on the expectations generated by the packages on consumers. Considering that at purchase stage consumers would not spend more than a few seconds evaluating a package, the first ideas that come to their minds would be the ones that determine their behaviour and expectations regarding the product. In this context, word association could be a powerful technique to identify consumer spontaneous associations regarding food packages. Compared to other methodologies, such as focus group, this approach has the advantage that consumer responses might not be influenced by other participants or highly trained interviewers. Results from the word association task, expected liking and willingness to purchase scores provided concordant results. It can be said because the expected liking and willingness to purchase scores were correlated to words that implied a hedonic reaction towards the desserts (such as delicious and disgusting). Word association and conjoint analysis provided information about both how package features influenced consumer purchase intention and which sensory expectations were created by the packages. This approach consists on a simple task for consumers and could be useful during package design in order to assure that the package attracts the consumer, and creates appropriate expectations regarding the product. If sensory and hedonic expectations created by the packages are not met when consumers try the product, disconfirmation could occur; decreasing the probability of consumers repeated purchase. Thus, assuring that consumers expect the product that really is inside the package could lead to a higher consumer satisfaction. However, further studies focusing on product tasting and satisfaction have to be carried out, in order to investigate how disconfirmation of the sensory and hedonic expectations generated by packages affect consumers reaction to food products. Moreover, further research is recommended in order to investigate the applicability of the proposed methodology to more complex products, including other package features.
Acknowledgments The authors are indebted to the Sensory Science Scholarship Fund and GlaxoSmithKline Consumer Healthcare for the Rose Marie Pangborn Sensory Science Scholarship granted to Gastón Ares. The authors would also like to thank Victoria Puyares for her help with the design of the milk dessert package cards, and to all the people who participated in the study.
References Ampuero, O., & Vila, N. (2006). Consumer perceptions of product packaging. Journal of Consumer Marketing, 23, 100–112. Ares, G., & Deliza, R. (2010). Identifying important package features of milk desserts using free listing and word association. Food Quality and Preference, 21, 621–628. Bécue-Bertaut, M., Álvarez-Esteban, R., & Pagès, J. (2008). Ratings of products through scores and free-text assertions: Comparing and combining both. Food Quality and Preference, 19, 122–134. Bécue-Bertaut, M., & Pagès, J. (2008). Multiple factor analysis and clustering of a mixture of quantitative, categorical and frequency data. Computational Statistics and Data Analysis, 52, 3255–3268.
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937 Deliza, R., & MacFie, H. J. H. (1996). The generation of sensory expectation by external cues and its effect on sensory perception and hedonic ratings: A review. Journal of Sensory Studies, 11, 103–128. Deliza, R., MacFie, H., & Hedderley, D. (2003). Use of computer-generated images and conjoint analysis to investigate sensory expectations. Journal of Sensory Studies, 18, 465–486. Deliza, R., Rosenthal, A., & Silva, A. L. S. (2003). Consumer attitude towards information on non conventional technology. Trends in Food Science and Technology, 14(1), 39–43. Doise, W., Clémence, A., & Lorenzi-Cioldi, F. (1993). The quantitative analysis of social representations. London: Harvester Wheatsheaf. Guerrero, L., Claret, A., Verbeke, W., Enderli, G., Zakowska-Biemans, S., Vanhonacker, F., et al. (2009). Perception of traditional food products in six European regions using free word association. Food Quality and Preference, 21(2), 225–233. Husson, F., Josse, J., Lê, S., Mazet, J. (2007). FactoMineR: Factor analysis and data mining with R. R package version 1.04. URL. Hutchings, J. B. (2003). Expectations and the food industry: The impact of color and appearance. New York: Kluwer Academic/Plenum Publishers. Jaeger, S. R. (2006). Non-sensory factors in sensory science research. Food Quality and Preference, 17, 132–144. Lange, C., Issanchou, S., & Combris, P. (2000). Expected versus experienced quality: trade-off with price. Food Quality and Preference, 11, 289–297. Lavin, J., & Lawless, H. T. (1998). Effects of color and odor on judgements of sweetness among children and adults. Food Quality and Preference, 9, 283– 289. Lê, S., Josse, J., & Husson, F. (2008). FactoMineR: An R package for multivariate analysis. Journal of Statistical Software, 25(1). MacFie, H. J. H., Bratchell, N., Greenhoff, K., & Vallis, L. V. (1989). Designs to balance the effect of order of presentation and first-order carry-over effects in hall tests. Journal of Sensory Studies, 4, 129–148. Marshall, D., Sutart, M., & Bell, R. (2006). Examining the relationship between product package colour and product selection in preschoolers. Food Quality and Preference, 17, 615–621.
937
McDaniel, C., & Baker, R. C. (1977). Convenience food packaging and the perception of product quality. Journal of Marketing, October, 57–58. McNeal, J. U., & Ji, M. F. (2003). Children’s visual memory of packaging. Journal of Consumer Marketing, 20, 400–427. Modell, S. (2005). Triangulation between case study and survey methods in management accounting research: An assessment of validity implications. Management Accounting Research, 16, 231–254. Moskowitz, H., Reiner, M., Lawlor, J. B., & Deliza, R. (2009). Packaging research in food product design and development. Hoboken: Wiley–Blackwell. Murray, J. M., & Delahunty, C. M. (2000). Mapping consumer preference for the sensory and packaging attributes of Cheddar cheese. Food Quality and Preference, 11, 419–435. Naes, T., Kubberod, E., & Sivertsen, H. (2001). Identifying and interpreting market segments using conjoint analysis. Food Quality and Preference, 12, 133–143. R Development Core Team (2007). R: A language and environment for statistical computing. Vienna: R Foundation for Statistical Computing. ISBN: 3-900051-07-0 Rodríguez Tarango, J. A. (2003). Introducción a la Ingeniería en Envase y Embalaje. In J. A. Rodríguez Tarango (Ed.), Manual de ingeniería y diseño en envase y embalaje para la industia de los alimentos, farmaceútica, química y de cosméticos (pp. 1:1–1:6). México: Instituto Mexicano de Profesionales en Envase y Envalaje S.C. Roininen, K., Arvola, A., & Lähteenmäki, L. (2006). Exploring consumers’ perception of local food with two different qualitative techniques: Laddering and word association. Food Quality and Preference, 17, 20–30. Schmitt, N. (1998). Quantifying word association responses: What is native-like? System, 26, 389–401. Tuorila, H. M., Meiselman, H. L., Cardello, A. V., & Lesher, L. L. (1998). Effect of expectations and the definition of product category on the acceptance of familiar foods. Food Quality and Preference, 9, 421–430. Wadsworth, G. (2000). Hearing midlife voices: Assessing different methods for researching women’s experiences of menopause and midlife. Women’s Studies International Forum, 23, 645–654. Wagner, W., Valencia, J., & Elejabarrieta, F. (1996). Relevance, discourse and the hot stable core of social representations and structural analysis of word associations. British Journal of Social Psychology, 35, 331–351.
Contents lists available at ScienceDirect
Food Quality and Preference journal homepage: www.elsevier.com/locate/foodqual
Studying the influence of package shape and colour on consumer expectations of milk desserts using word association and conjoint analysis Gastón Ares a,*, Rosires Deliza b,c a Sección Evaluación Sensorial, Departamento de Ciencia y Tecnología de Alimentos, Facultad de Química, Universidad de la República (UdelaR), Gral. Flores 2124. C.P. 11800, Montevideo, Uruguay b EMBRAPA (Brazilian Agricultural Research Corporation) Labex Europe, Dijon, France c INRA, UMR CSGA, 17 rue Sully, F-21065 Dijon, France
a r t i c l e
i n f o
Article history: Received 30 August 2009 Received in revised form 19 January 2010 Accepted 8 March 2010 Available online 12 March 2010 Keywords: Word association Expectations Consumer studies Conjoint analysis Milk desserts Packaging
a b s t r a c t Food packaging plays a major role in attracting consumer attention and generating sensory and hedonic expectations; which could affect their product perception and purchase decisions. In the present study word association and conjoint analysis were used to study the influence of package shape and colour on consumer expectations of milk desserts. Six images of milk dessert packages with different colour and shape were presented to 105 consumers, who were asked to complete a word association task and to score their expected liking and willingness to purchase the desserts. Both package shape and colour affected consumers expected liking scores and their sensory expectations regarding the desserts. Consumers associations were mainly related to sensory characteristics. Both methodologies provided an interesting insight on the consumer’s expectations generated by the packages and could be useful in order to design packages which create appropriate expectations regarding the product. Ó 2010 Elsevier Ltd. All rights reserved.
1. Introduction Food package is the container that holds, protects, preserves and identifies the product, and which also facilitates its handling, storage and commercialization (Rodríguez Tarango, 2003). Packaging also plays a major role in attracting consumer attention and influencing consumer purchase decisions. In the context of current self-service food retailing, packaging provides food companies the last chance to persuade consumers to buy the product before brand selection (McDaniel & Baker, 1977). Therefore, all packaging elements have to be combined to attract the consumer when purchasing the product (McNeal & Ji, 2003). According to several authors, shape and colour are important features during package design (Ampuero & Vila, 2006; Hutchings, 2003; Marshall, Sutart, & Bell, 2006). Apart from influencing consumer purchase decision, food package may also create expectations in the consumer (Deliza, MacFie, & Hedderley, 2003; Lange, Issanchou, & Combris, 2000; Rodríguez Tarango, 2003). If the hedonic expectations created by the package are high, the consumer may be interested in the product and choose to buy it. However, sensory and hedonic expectations could also affect consumer response when tasting the product (Tuorila,
* Corresponding author. Tel.: +5982 9245735; fax: +5982 9241906. E-mail address: [email protected] (G. Ares). 0950-3293/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodqual.2010.03.006
Meiselman, Cardello, & Lesher, 1998). When the product is tasted, the expected sensory characteristics of the product are compared with the products’ real characteristics, leading to confirmation or disconfirmation (Deliza & MacFie, 1996). If the consumer confirms his (her) expected sensory characteristics he (she) would likely repeat product purchase. However, if the expected sensory characteristics are not perceived, the consumer will probably not buy the product again (Deliza & MacFie, 1996). Therefore, manufacturers should use food package to attract consumers’ attention in order to increase their interest in buying the product; but also to generate sensory and hedonic expectations that match the products’ real characteristics. Although food companies usually invest large amounts of money on package design there are not many published studies about the influence of package characteristics on consumer expectations of food products (Deliza & MacFie, 1996; Lange et al., 2000; Moskowitz, Reiner, Lawlor, & Deliza, 2009; Murray & Delahunty, 2000). In this context, it is very important to rely on methodologies that allow a precise identification of consumer expectations generated by packages. Word association is a qualitative methodology widely used in psychology and sociology (Doise, Clémence, & Lorenzi-Cioldi, 1993; Schmitt, 1998). This methodology is based on the assumption that giving a stimulus to respondents and asking them to write down the associations that come to their minds gives relatively unrestricted access to mental representations of the stimulus.
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
When dealing with food products, the associations that first come to the respondents’ mind may be the most relevant for consumers’ decisions related to product purchase (Roininen, Arvola, & Lähteenmäki, 2006). The ideas expressed within a word association task are spontaneously elicited and might be subjected to fewer constraints than that typically imposed in interviews or closed questionnaires (Wagner, Valencia, & Elejabarrieta, 1996). For these reasons, this technique could be an interesting tool for exploring consumers’ perception of food products. In this task, consumers’ elicited terms about a food product could be related to their sensory and hedonic expectations. Conjoint analysis is a useful tool to investigate the effect of different package features on consumer purchase intention (Deliza, Rosenthal, & Silva, 2003). This methodology could be used to estimate the relative importance of different package attributes on consumer perception of food products. The aims of the present work were to: (a) evaluate the applicability of word association to study consumer associations about milk dessert packages as a mean to understand their expectations, and (b) study the influence of package shape and colour on consumer expectations of milk desserts. 2. Materials and methods
931
several groups of consumers, including children and elderly people. Besides, there is increasing marketing activity regarding milk desserts in Uruguay, as most dairy companies have launched new low-fat and low-calorie desserts. Milk dessert packages were designed using two categorical factors: shape and colour. These package features were selected considering previous studies carried out with Uruguayan consumers using free listing and word association (Ares & Deliza, 2010), and the fact that they are responsible for the highest variability of packages available in Uruguayan market. Two shapes (round and square) and three colours (white, black and yellow) were considered in the study. Thus, six images of milk packages were created following a full factorial experimental design. They were printed in glossy paper, and coated with contact paper yielding six different cards. The milk dessert packages images were obtained from commercial milk dessert packages and retouched using Adobe Photoshop 7.0 (Adobe Systems Incorporated, 2002). Two examples of the cards used in the study are shown in Fig. 1. 2.3. Consumer evaluation The six cards were presented to participants numbered with three-digit random codes, and following a balanced order for each participant (MacFie, Bratchell, Greenhoff, & Vallis, 1989).
2.1. Participants The study was conducted in the city of Montevideo (Uruguay). One-hundred and five people participated in the study; 39% of which were males and 61% females. Participants ranged in age from 18 to 77 years old (mean 33.7 years old, standard deviation 14.9 years old); being 63% of the participants under 35 years old and the other 37% of the participants were 35 or more years old. All participants consumed milk desserts at least once a week, and were randomly recruited at shopping areas, universities campus and public places. The studied consumer sample can be regarded as a convenience sample which is usually considered in exploratory studies when the main interest is to get an approximation to a research subject (Guerrero et al., 2009).
2.3.1. Word association task Consumers were asked to evaluate each of the six cards with the packages one at a time, and to write down the first four images, associations, thoughts or feelings that came to their minds when thinking of the dessert inside the packages. 2.3.2. Conjoint analysis task After completing the word association task, participants were also asked to evaluate their expected liking of the desserts using a 9-point hedonic scale labelled on the left with ‘dislike very much’ and on the right with ‘like very much’, and their willingness to purchase the desserts using a 9-point structured scale labelled on the left with ‘I would definitively not buy it’ and on the right with ‘I would definitively buy it’.
2.2. Stimuli
2.4. Data analysis
A milk dessert was selected as base product for the present study. This selection was made considering that these products are widely consumed worldwide, and particularly in Uruguay, by
2.4.1. Conjoint analysis Analysis of variance (ANOVA) was performed on data from expected liking and willingness to purchase. The ANOVA method
Fig. 1. Two examples of the images used in the study (a) round yellow package and (b) square black package.
932
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
considered in the present study was the following (Naes, Kubberod, & Sivertsen, 2001): Y = main effect for package variables (colour and shape) + main random effect for consumer + interactions between package variables + interactions between consumer and package variables + random error. When the effects were significant, honestly significant differences were calculated using Tukey’s test. Differences were considered significant when p < 0.05. All statistical analyses were performed using GenStat for Windows Discovery Edition 2 (VSN International Ltd., Hempstead, UK). 2.4.2. Qualitative analysis of the elicited words The elicited associations were qualitatively analyzed. First, a search for recurrent terms within each package was performed. Terms with similar meaning were grouped into different categories within each package. This classification was performed independently by three researchers considering personal interpretation of the meaning of the words and word synonymy as determined by a Spanish dictionary. The three researchers had previous experience in analyzing qualitative data from open-ended-questions and word association tasks. After individually evaluating the data, a meeting of the researchers was undertaken in order to check the agreement between their classifications. The final categories and their names were determined by consensus between the three researchers considering their three independent classifications and discussion between them. This triangulation technique has been used by other authors dealing with qualitative techniques (Guerrero et al., 2009; Modell, 2005; Wadsworth, 2000). Categories comprising terms mentioned by more than 10% of participants were considered. Frequencies in each category were determined by counting the number of participants that used those words to describe the concept. Then, associations from the different packages with similar meaning were merged. This task was carried out by the three researchers that performed the classification of terms. Frequencies of word counting in each category were calculated for each package. Chi-square was calculated for evaluating differences in consumers’ perception of the milk dessert packages. 2.4.3. Multiple Factor Analysis Multiple Factor Analysis (MFA) is a factor analysis method that deals with data sets composed of both quantitative variables and frequency tables, and analyzes observations described by different groups of variables (Bécue-Bertaut & Pagès, 2008; Bécue-Bertaut, Álvarez-Esteban, & Pagès, 2008). In the present study, three groups of variables were considered: frequency of mention of terms elicited in the word association task, expected liking and willingness to purchase scores. Therefore, MFA was performed to provide an integrated representation of the packages and of the relationships between consumers’ associations, and scores for expected liking and willingness to purchase. MFA analysis was performed on a table juxtaposing the frequency table of consumer associations and consumer scores for expected liking and willingness to purchase, using FactoMineR (Husson, Josse, Lê, & Mazet, 2007; Lê, Josse, & Husson, 2008) in R language (R Development Core Team, 2007). 3. Results 3.1. Influence of shape and colour on consumer expected liking and willingness to purchase Consumer scores for expected liking of the desserts ranged from 4.8 to 6.7, whereas scores for willingness to purchase ranged from 4.5 to 6.6. According to ANOVA consumers showed highly significant different degrees of expected liking and willingness to pur-
Table 1 ANOVA results for expected liking and willingness to purchase scores. Effect Shape Colour Shape colour Consumer shape Consumer colour *
Expected liking *
3.8 21.9*** 0.5ns 0.9ns 1.3ns
Willingness to purchase 1.6ns 22.0*** 0.9ns 0.5ns 0.8ns
Significant effect at p < 0.05. Significant effect at p < 0.001. No significant effect (p > 0.05).
***
ns
chase of the desserts, suggesting that consumers perceived packages differently. Furthermore, ANOVA revealed that the main effect of the conjoint variables package shape and colour had a highly significant effect on consumer expected liking, as shown in Table 1. However, for willingness to purchase only package colour had a significant effect. The interaction between the conjoint variables package shape colour was not significant for consumer expected liking and willingness to purchase scores; which indicates that consumers independently evaluated the shape and colour of the packages. The interactions between package variables and consumer were also not significant for both expected liking and willingness to purchase scores. Mean effects part-worth utilities for expected liking and willingness to purchase were calculated and are shown in Table 2. Colour had higher part-worth utilities than shape, indicating that the former package feature was more important for consumers. For expected liking the relative importance of colour was 82.5%, whereas for willingness to purchase it was 88.4%. Differences were found in the utilities of colour for expected liking and willingness to purchase. As shown in Table 2, expected liking scores were able to discriminate between all levels of the evaluated variables. Round shape showed a highly significant higher utility than square for expected liking, but no significant differences were found between these features for willingness to purchase. Regarding package colour, yellow showed the highest utility for expected liking, followed by white and finally black packages; whereas no significant differences (p > 0.05) were found between the willingness to purchase of black and white packages. 3.2. Word association 3.2.1. Consumer elicited terms in the word association task The elicited words were merged into 28 categories, corresponding to those mentioned by more than 10% of the participants, as explained in Section 2.4.2. Table 3 shows the frequencies in which each category was mentioned for each package. Consumer associations were related to sensory characteristics of the desserts,
Table 2 Conjoint analysis results (part-worth utilities and relative importance of each attribute) for expected liking and willingness to purchase scores. Attributes and levels
Expected liking
Willingness to purchase
Shape Round Square Relative importance
0.205a 0.205b 17.5%
0.145a 0.145a 11.6%
Colour Black White Yellow Relative importance
0.73c 0.23b 0.97a 82.5%
0.60b 0.50b 1.10a 88.4%
Values with different letters within the same column for the same attribute are significantly different (p < 0.05) according to Tukey’s test.
933
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937 Table 3 Number of mentions of terms for the six milk dessert packages considered in the word association task. Term*
Vanilla Chololate Creamy Delicious Sweet Thick Milky Soft Disgusting Small serving Low-calorie Tasteless Egg custard Adequate serving Runny Dulce de leche** Premium Yellow Interesting Plain Bitter Dark colour Fruity Childish Light colour Strong flavour Sour Caramel * **
Milk dessert package Round black
Round white
Round yellow
Square black
Square white
Square yellow
0 53 17 13 17 8 5 4 16 14 3 2 4 0 9 2 12 2 12 0 9 12 5 3 0 7 0 2
26 0 24 15 9 2 17 18 6 17 0 19 2 0 10 2 0 0 2 11 0 0 5 11 4 0 6 0
58 0 30 22 25 9 5 24 0 18 2 3 9 0 11 15 3 11 3 2 0 0 0 5 4 0 0 0
0 57 3 11 4 18 5 2 24 0 12 0 8 12 3 2 15 3 12 0 22 14 2 0 0 15 0 2
21 0 17 15 7 12 29 10 12 0 20 16 2 15 5 0 3 2 2 17 0 0 11 2 4 0 11 0
38 0 17 16 16 21 3 6 3 0 10 3 18 15 0 15 3 17 3 2 0 0 2 2 11 0 2 15
Only terms mentioned by more than 10% of the participants were considered. Dulce de leche is a kind of sweetened condensed milk, typical of Latin American countries such as Argentina, Brazil and Uruguay.
mainly flavour and texture attributes. As shown in Table 3, the most mentioned associations were vanilla, chocolate, creamy, and delicious; indicating the importance of packaging in generating sensory and hedonic expectations of milk desserts. Consumer associations were highly significantly different for the six evaluated packages (v2 = 1229, p < 0.001), suggesting that package shape and colour significantly affected consumer expectations of the desserts inside evaluated packages. Differences in consumer associations were found with package colour and shape, as shown in Table 3. Yellow packages were more associated with sweet vanilla or dulce de leche desserts; whereas black packages were associated with bitter, strong flavoured chocolate desserts regarded as disgusting or premium and interesting. Besides, white packages were associated with milky vanilla or plain desserts, which were considered tasteless. On the other hand, round packages tended to be more associated with runny, creamy and soft desserts; whereas square packages were associated with thick, low-calorie milk desserts. These results suggest that package shape and colour affected consumers’ sensory and hedonic expectations of the desserts. 3.2.2. Multiple Factor Analysis Multiple Factor Analysis (MFA) was used to study the relationships between the packages and consumer associations, as well as between consumer expectations and consumer expected liking and willingness to purchase. The first three dimensions of the MFA accounted for by 95.1% of the variance of the experimental data, representing 54.6%, 24.4%, and 16.1% of the variance, respectively. As shown in Table 4, the eigenvalue of the first dimension indicates that it can be considered an important direction in explaining the dispersion of both consumer scores and the frequency table of the terms elicited in the word association task (Bécue-Bertaut et al., 2008). Both the scores and the associations contributed in a balanced way to the inertia of the first dimension (52.7% and
Table 4 Eigenvalues and percentage of the variance of the experimental data explained by the first four dimensions of the Multiple Factor Analysis (MFA). Dimension from MFA
Eigenvalue
Percentage of variance (%)
Cumulative percentage of variance (%)
1 2 3 4
1.837 0.822 0.540 0.102
54.6 24.4 16.1 3.0
54.6 79.0 95.1 98.1
47.3%, respectively). On the contrary, the associations explained more than 95% of the inertia of the second and third dimensions, indicating that these dimensions were mainly explained by consumer associations of the packages and not by their scores. The first dimension of the MFA was positively correlated with expected liking and willingness to purchase scores, and with words related to the expected flavour of the desserts (such as sweet, Dulce de leche, and vanilla), and to a positive hedonic reaction (delicious), as shown in Fig. 2. Besides, it was negatively correlated to a category including terms related to a negative hedonic reaction (disgusting). The second dimension was positively correlated with words related to thickness and negatively with fruity, sour, milky flavour, plain, and tasteless. On the other hand, the third dimension was related to the serving size and to the category low-calorie. As shown in Fig. 2, expected liking and willingness to purchase scores were positively correlated with the category named delicious, and negatively to words such as disgusting. This indicates the concordance of both types of evaluations. Fig. 3 shows the representation of the packages in the MFA dimensions. The first and second dimensions mainly sorted the packages into three groups; which corresponded to the three evaluated colours. This is in agreement with the abovementioned
934
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
(a)
Dimension 2: 24.4%
1
0.8
Premium Bitter Interesting Dark colour Strong flavour Chocolate
Thick
Egg custard
0.6
Caramel
Yellow Dulce de leche
0.4
Disgusting
Willingness to purchase
Adequate serving 0.2
Sweet Expected liking
Low-calorie 0 -1.5
-1
-0.5
LIght colour 0
1Dimension
0.5
1: 54.6%1.5
Vanilla Delicious
-0.2
Small serving
-0.4
Creamy Soft
Thin
-0.6
Fruity
Childish Sour -0.8
Plain Tasteless
Milky flavour
-1
-1.2
(b)
1.2
Dimension 3: 16.1%
1
Adequate serving Low-calorie 0.8 Sour
Thick
0.6
Caramel LIght colour
Plain
Fruity Milky flavour
0.4
Egg custard Yellow
0.2 Tasteless
Dulce de leche
Dimension 1: 54.6% -1.5
0
Disgusting
-1
Premium
-0.5
0
Bitter
0.5
-0.2
Soft
Strong flavour Dark colour
Vanilla Willingness to purchase Expected liking 1 1.5 Delicious
Interesting
-0.4
Creamy Sweet
Childish
Chocolate -0.6
-0.8
Thin
Small serving
-1
(c)
1.2
Dimension 3: 16.1%
1
Adequate serving Low-calorie
0.8
Sour
Thick
LIght colour
0.6
Caramel Plain
Fruity
0.4
Milky flavour
Yellow
Tasteless
0.2
Vanilla
Dulce de leche Dimension 2: 24.4%
0 -1.2
-1
-0.8
Egg custard
-0.6
-0.4
-0.2
0
0.2
Delicious
-0.4
0.6
0.8
1
Bitter Premium Strong flavour
-0.2
Creamy Soft Childish
Disgusting 0.4
Sweet
Dark colour Interesting Chocolate
-0.6
Thin
Small serving
-0.8
-1
Fig. 2. Representation of the words and consumer scores for expected liking and willingness to try in the first three dimensions of the Multiple Factor Analysis.
higher relative importance of colour on consumer expected liking and willingness to purchase scores.
Therefore, the main differences between consumers’ associations regarding the packages were due to their different colour.
935
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
(a)
2
S-B
Dimension 1: 54.6%
Dimension 2: 24.4%
1
S-Y
R-B 0
-2.5
-1.5
-0.5
0.5
1.5
R-Y
2.5
-1
S-W
R-W
-2
(b)
1.5
Dimension 3: 16.1%
S-W
S-Y
0.5
Dimension 2: 24.4%
S-B -2.5
-1.5
-0.5
R-W
0.5
1.5
2.5
-0.5
R-Y R-B
-1.5
(c)
1.5
Dimension 3: 16.1%
S-W
S-Y
0.5
Dimension 1: 54.6%
S-B -2.5
-1.5
-0.5
0.5 -0.5
1.5
2.5
R-W R-Y
R-B
-1.5
Fig. 3. Representation of the packages in the first three dimensions of the Multiple Factor Analysis. Description of the packages: round black (RB), round yellow (RY), round white (RW), square black (SB), square yellow (SY) and square white (SW).
Yellow packages were located to the right of the first dimension; being associated with sweet, delicious, vanilla and dulce de leche desserts. Also, these packages showed the highest expected liking and willingness to purchase scores. On the other hand, white packages were located at mid-values for the first dimension and negative values of the second dimension; corresponding to plain, sour, tasteless, and fruity milk desserts. Meanwhile, black packages were located in the second quadrant of the first and second dimension; being mainly associated with bitter dark coloured, chocolate des-
serts regarded as disgusting, interesting and premium. Consumers mainly associated different package colour with different flavours; indicating that colour mainly generated sensory expectations related to the flavour of the dessert inside the package. As shown in Fig. 3, black packages were associated with contradictory terms such as interesting, premium and disgusting; which indicates heterogeneity in consumer attitude towards this package colour. According to the results of the present study, it seemed that a group of consumers rejected black packages, as they associated
936
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937
them with disgusting desserts; whereas another consumer group expected interesting and premium desserts. Furthermore, in the representation of the second and third dimensions of the MFA packages were sorted according to their shape (c.f. Fig. 3). Square packages tended to be located at positive values of the second dimension, whereas round packages were located at negative values of this dimension. As shown in Table 3 and Fig. 3, round packages were associated with runny desserts, whereas square packages were associated with thick. This might indicate that package shape created sensory expectations regarding the texture of the desserts. Also, the size of the serving was perceived differently for round and square packages. Consumers considered the serving of a square package as adequate, whereas the serving of a round package was regarded as small. Furthermore, the package’s shape and colour affected the specific type of dessert consumers expected to find inside the packages. As shown in Table 3 and Fig. 3, consumers related yellow square packages with words such as thick, caramel, and egg custard. Meanwhile, yellow round packages were associated with creamy, runny and soft desserts. 4. Discussion 4.1. Influence of package shape and colour on consumers’ expectations, expected liking and willingness to purchase milk desserts Both colour and shape significantly affected consumers’ associations, expected liking and willingness to purchase. Consumer associations regarding package colour were mainly related to flavour; in agreement with previous studies (Hutchings, 2003; Lavin & Lawless, 1998; Marshall et al., 2006). Differences in expected liking scores due to package colour might be related to consumers’ hedonic reaction towards the expected flavour of the desserts. This could explain the fact that colour had a larger influence than shape in consumer expected liking and willingness to purchase scores. Consumers seemed to prefer packages that were associated with sweet, vanilla and dulce de leche flavoured milk desserts. On the other hand, differences in consumer associations due to differences in package shape were mainly related to sensory expectations related to texture characteristics (e.g. runny and thick) and to specific types of desserts (e.g. egg custard or low-calorie desserts) (c.f. Table 3 and Fig. 3). Apart from influencing expected flavour, package colour also affected texture expectations regarding the creaminess and softness of the desserts. As shown in Table 3, yellow round packages were more frequently associated with creamy and soft desserts than black or white ones. These results show the relevance of package characteristics, such as colour and shape, in creating sensory expectations on consumers, which could affect their product perception and acceptance. Besides, participants also associated certain package shapes and colours with specific products, such as egg custard or low-calorie desserts. Thus, during product and package development it would be important to study which sensory expectations packages are able to create in consumer’s mind. 4.2. Methodological issues The combination of word association and conjoint analysis provided interesting and valuable information regarding the influence of package shape and colour on consumer perception of milk desserts. The use of MFA allowed evaluating simultaneously consumer scores and free associations, providing a synthetic view of consumer’s perception of the packages.
Expected liking and willingness to purchase scores were useful to evaluate the influence of package shape and colour on consumer hedonic expectations and their purchase intention. However, both scores provided different results. This could also be related to the fact that price was not taken into account in the present study. Consumers did not take into account price when indicating their willingness to purchase the desserts despite the fact that this variable could have a large impact in consumers’ purchase decisions (Jaeger, 2006). Furthermore, word association task provided an insight on the expectations generated by the packages on consumers. Considering that at purchase stage consumers would not spend more than a few seconds evaluating a package, the first ideas that come to their minds would be the ones that determine their behaviour and expectations regarding the product. In this context, word association could be a powerful technique to identify consumer spontaneous associations regarding food packages. Compared to other methodologies, such as focus group, this approach has the advantage that consumer responses might not be influenced by other participants or highly trained interviewers. Results from the word association task, expected liking and willingness to purchase scores provided concordant results. It can be said because the expected liking and willingness to purchase scores were correlated to words that implied a hedonic reaction towards the desserts (such as delicious and disgusting). Word association and conjoint analysis provided information about both how package features influenced consumer purchase intention and which sensory expectations were created by the packages. This approach consists on a simple task for consumers and could be useful during package design in order to assure that the package attracts the consumer, and creates appropriate expectations regarding the product. If sensory and hedonic expectations created by the packages are not met when consumers try the product, disconfirmation could occur; decreasing the probability of consumers repeated purchase. Thus, assuring that consumers expect the product that really is inside the package could lead to a higher consumer satisfaction. However, further studies focusing on product tasting and satisfaction have to be carried out, in order to investigate how disconfirmation of the sensory and hedonic expectations generated by packages affect consumers reaction to food products. Moreover, further research is recommended in order to investigate the applicability of the proposed methodology to more complex products, including other package features.
Acknowledgments The authors are indebted to the Sensory Science Scholarship Fund and GlaxoSmithKline Consumer Healthcare for the Rose Marie Pangborn Sensory Science Scholarship granted to Gastón Ares. The authors would also like to thank Victoria Puyares for her help with the design of the milk dessert package cards, and to all the people who participated in the study.
References Ampuero, O., & Vila, N. (2006). Consumer perceptions of product packaging. Journal of Consumer Marketing, 23, 100–112. Ares, G., & Deliza, R. (2010). Identifying important package features of milk desserts using free listing and word association. Food Quality and Preference, 21, 621–628. Bécue-Bertaut, M., Álvarez-Esteban, R., & Pagès, J. (2008). Ratings of products through scores and free-text assertions: Comparing and combining both. Food Quality and Preference, 19, 122–134. Bécue-Bertaut, M., & Pagès, J. (2008). Multiple factor analysis and clustering of a mixture of quantitative, categorical and frequency data. Computational Statistics and Data Analysis, 52, 3255–3268.
G. Ares, R. Deliza / Food Quality and Preference 21 (2010) 930–937 Deliza, R., & MacFie, H. J. H. (1996). The generation of sensory expectation by external cues and its effect on sensory perception and hedonic ratings: A review. Journal of Sensory Studies, 11, 103–128. Deliza, R., MacFie, H., & Hedderley, D. (2003). Use of computer-generated images and conjoint analysis to investigate sensory expectations. Journal of Sensory Studies, 18, 465–486. Deliza, R., Rosenthal, A., & Silva, A. L. S. (2003). Consumer attitude towards information on non conventional technology. Trends in Food Science and Technology, 14(1), 39–43. Doise, W., Clémence, A., & Lorenzi-Cioldi, F. (1993). The quantitative analysis of social representations. London: Harvester Wheatsheaf. Guerrero, L., Claret, A., Verbeke, W., Enderli, G., Zakowska-Biemans, S., Vanhonacker, F., et al. (2009). Perception of traditional food products in six European regions using free word association. Food Quality and Preference, 21(2), 225–233. Husson, F., Josse, J., Lê, S., Mazet, J. (2007). FactoMineR: Factor analysis and data mining with R. R package version 1.04. URL
937
McDaniel, C., & Baker, R. C. (1977). Convenience food packaging and the perception of product quality. Journal of Marketing, October, 57–58. McNeal, J. U., & Ji, M. F. (2003). Children’s visual memory of packaging. Journal of Consumer Marketing, 20, 400–427. Modell, S. (2005). Triangulation between case study and survey methods in management accounting research: An assessment of validity implications. Management Accounting Research, 16, 231–254. Moskowitz, H., Reiner, M., Lawlor, J. B., & Deliza, R. (2009). Packaging research in food product design and development. Hoboken: Wiley–Blackwell. Murray, J. M., & Delahunty, C. M. (2000). Mapping consumer preference for the sensory and packaging attributes of Cheddar cheese. Food Quality and Preference, 11, 419–435. Naes, T., Kubberod, E., & Sivertsen, H. (2001). Identifying and interpreting market segments using conjoint analysis. Food Quality and Preference, 12, 133–143. R Development Core Team (2007). R: A language and environment for statistical computing. Vienna: R Foundation for Statistical Computing. ISBN: 3-900051-07-0 Rodríguez Tarango, J. A. (2003). Introducción a la Ingeniería en Envase y Embalaje. In J. A. Rodríguez Tarango (Ed.), Manual de ingeniería y diseño en envase y embalaje para la industia de los alimentos, farmaceútica, química y de cosméticos (pp. 1:1–1:6). México: Instituto Mexicano de Profesionales en Envase y Envalaje S.C. Roininen, K., Arvola, A., & Lähteenmäki, L. (2006). Exploring consumers’ perception of local food with two different qualitative techniques: Laddering and word association. Food Quality and Preference, 17, 20–30. Schmitt, N. (1998). Quantifying word association responses: What is native-like? System, 26, 389–401. Tuorila, H. M., Meiselman, H. L., Cardello, A. V., & Lesher, L. L. (1998). Effect of expectations and the definition of product category on the acceptance of familiar foods. Food Quality and Preference, 9, 421–430. Wadsworth, G. (2000). Hearing midlife voices: Assessing different methods for researching women’s experiences of menopause and midlife. Women’s Studies International Forum, 23, 645–654. Wagner, W., Valencia, J., & Elejabarrieta, F. (1996). Relevance, discourse and the hot stable core of social representations and structural analysis of word associations. British Journal of Social Psychology, 35, 331–351.