PaPer Ital. J. Food Sci., vol. 27 - 2015 521 - Keywords: cheese preference, children food preference, colour preference, gender, neophobia, nutrition education - Children preferenCes of Coloured fresh Cheese prepared during an eduCational laboratory f. tesini*1, M. laureati2, r. palagano1, M. Mandrioli1, e. pagliarini2 and t. gallina tosChi1,3 1DISTAL, Department of Agricultural and Food Sciences, Alma Mater Studiorum - University of Bologna, P.zza Goidanich 60, 47521 Cesena, FC, Italy 2Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Celoria 2, 20133Milan, Italy 3CIRI, Department of Agricultural and Food Sciences, Interdepartmental Centre for Industrial Research in Agri-Food, Alma Mater Studiorum - University of Bologna, P.zza Goidanich 60, 47521 Cesena, FC, Italy *Corresponding author: federica.tesini@unibo.it AbstrAct choices among young consumers are mainly driven by food preferences; in particular, a con- nection between appearance and acceptance of food has been highlighted, together with a gener- al lack of knowledge of food processing. For these reasons, educational activities are important to increase scientific knowledge and awareness. the cheese-making educational laboratory de- scribed herein involved children, adolescents, and their parents/teachers in the preparation of fresh and naturally-coloured cheeses. At the end of the activity, both the colour preference and possible relation between preference and colour of cheese prepared were investigated administer- ing a short questionnaire. 522 Ital. J. Food Sci., vol. 27 - 2015 INtrODUctION Food preference has a fundamental role in driving consumer’s choices and habits, espe- cially in children (cOOKE, 2007; NIcKLAUs et al., 2004, LAUrEAtI et al., 2015a). therefore, the number of food products specifically developed for children is growing and this market is acquir- ing increasing importance (IssANcHOU, 2015). consequently, the youngest consumers are frequently involved in research and development programs, since their food habits will influence choices as they grow older and because their pref- erences, even if partly driven by advertisements (UstJANAUsKAs et al., 2014), seem to be strictly related to the sensory aspects of food (PAGLIAr- INI et al., 2005; MUstONEN and tUOrILA, 2010). In 1994, Moskowitz (MOsKOWIts, 1994) high- lighted how a visually pleasing product tends to be more appreciated by children, as visual attrib- utes seem to be, among different sensory charac- teristics, those that mainly determine its success (KILDEGAArD et al., 2011; tOPcU, 2015). Indeed, children tend to create an “ideal picture” of each food product that can be related to their own idea of “good”; this picture represent a sort of refer- ence point that can be used to dislike products whose appearance is not close to their expecta- tion (MUstONEN and tUOrILA, 2009). this phenomenon, called food neophobia, is defined as the fear of eating new or unfamiliar food (PLINEr and HObDEN 1992) and is related to both the quality and variety of diet (LAUrEA- tI et al., 2015b). Nutritional education and food-related diseas- es prevention activities can be used for children and teenagers in order to: i) reduce the impact of poor food habits on health, and ii) avoid food neo- phobia, mainly responsible for refusing consump- tion of fruits and vegetables (WArDLE et al., 2003). Moreover, a lack of awareness of procedural knowl- edge, both in terms of food processing and nutri- tional values, must be taken into account (WOrs- LEY, 2002), highlighting the link between tradition- al food preparation and sensory properties (LAU- rEAtI et al., 2006). Nowadays, food education is mainly based on the social-cognitive theory (sct) (bANDUrA and ADAMs 1977), which incorporates the interac- tion of personal, environmental and behavioural factors. According to this theory, principles that are highly influential in establishing changing food behaviour in children are both models and repeated exposure. Among the models, those that have been found to be effective in children include cartoon charac- ters, peers, mothers, unfamiliar adults and teach- ers; moreover, children seem to be influenced more by the behaviour of multiple rather than single models (LOWE et al., 2004). Furthermore, accord- ing to Zajonc’s “mere exposure” theory (ZAJONc, 1968), repeated exposure to a specific food increas- es the liking and consumption of that food (cOOKE et al., 2011; WArDLE et al., 2003b) through a mechanism that is believed to be a “learned safe- ty” behaviour (KALAt and rOZIN, 1973). Accord- ing to this theory, repeated ingestion of an unfa- miliar food without negative consequences leads to increased acceptance of that food. several educational interventions for food have investigated all these factors, reporting promising results, especially for consumption of fruits and vegetables (EVANs et al., 2012; LAU- rEAtI et al., 2014; rEVErDY et al., 2008). both principles of imitation and repeated exposure characterise food laboratories aimed at involv- ing children in food preparation, thus familiar- ising them with food ingredients and technolo- gies. Furthermore, it has been reported that the involvement of children in food preparation can contribute to increasing their acceptance for that food, according to the principle of repeated ex- posure (cHU et al., 2012). For all these reasons, food educational inter- ventions can play a relevant role in driving choice, interest and preference of children through bet- ter awareness of both sensory characteristics and technological process of traditional food products (MUstONEN and tUOrILA, 2010). the educational cheese-making activity re- ported herein, called Cheese making in one hour, was conceived by a committee of referees as part of the Festival della scienza 2014 (which took place in Genoa, Italy, from October 24 to No- vember 2, 2014) and is considered as a “teach- ing tool” in order to increase scientific informa- tion about the cheese-making process. this practical laboratory took the form of a family entertainment during which children and parents or teachers could share principles of tra- ditional cheese making, spending some family or educational time away from daily work, but related to increased knowledge of food science. the activity involved children, teenagers and adults (age from 6 to 87 years) in the traditional preparation of a fresh “primo sale like” cheese. cheeses were naturally coloured (using turmer- ic, rocket and beetroot juice), and in order to keep the attention of participants, each was ac- tively involved in the process by preparing his/ her personal small cheese. At the end of the activity, both the colour pref- erence and possible relation between the colour of cheese prepared and preference were inves- tigated by administration of a short and simple questionnaire. MAtErIALs AND MEtHODs the cheese-making activity involved 738 par- ticipants (395 females and 343 males) with an age between 5 and 87 years and divided in groups of no more than 30 individuals. both families and school classes could participate in the activity by asking the Festival staff to make Ital. J. Food Sci., vol. 27 - 2015 523 Fig. 1 - children at the cheese- making educational laboratory, during collection of a yellow-curd into a dedicated shaper. table 1 - Natural dyes and their amounts are reported togeth- er with the final colour of each cheese and its visual aspect. Cheese colour Dye Amount and appearance (g/L of milk) Yellow Turmeric 5 Pink Beetroot juice 20 White and green Rocket 20 a reservation; given the popularity of the Festi- val, mainly represented by children and partly by parents/teachers, a large number of partic- ipants were enrolled. Each participant had an active role in the laboratory, giving his/her con- tribution to one of the 4 phases of cheese mak- ing: 1) adding starter, rennet and natural flavour to milk; 2) curd cutting and synaeresis; 3) curd breaking and purge; 4) cheese shaping. During the Festival, the laboratory was repeated at least 3 times a day by 4 previously-trained scientific facilitators. Due to the fact that the cheese-mak- ing laboratory should last only one hour (relat- ed to the timing of the Festival), one pot (bar- tscher GmbH, Germany) was dedicated to each of the 4 main phases; in this way, participants could move from one pot to the next instead of proceeding step-by-step using a single pot such that each of the phases could be observed in a short length of time. Cheese-making phases 1) starter, rennet and milk natural flavouring Fresh whole cow milk was heated to 36° c and 17 g/L of natural whole yoghurt was added as a starter. In order to produce coloured cheeses, different natural dyes were added (rocket, tur- meric and beetroot juice) as reported in table 1. While turmeric and beetroot juice were added to the milk 30 minutes after the addition of start- er, together with 0.5 ml/l milk of liquid rennet (80% chymosin, 20% pepsin, provided by Gra- co), rocket was added during the last step of cheese shaping. 2) curd cutting and synaeresis After enzymatic coagulation, due to the addi- tion of liquid curd, the gel obtained was cut into 4 × 4 cm squares, and 30 minutes later partici- pants could observe the phenomena of curd sy- naeresis. 3) curd breaking and purge the squares of curd were broken into piec- es of approximately 1.5 cm; during this phase, rocket was added (20 g/l milk) for preparation of green cheese. 4) cheese shaping Finally, the small pieces of curd were collect- ed in dedicated shaper (60 g cheese shaper in polypropylene and polyethylene, tecnolatte srl, Italy) by each participant as shown in Fig. 1. 524 Ital. J. Food Sci., vol. 27 - 2015 5) Questionnaire At the end of the cheese-making laboratory, each participant was administered a dedicated and simplified questionnaire. the questionnaire contained a first part regarding personal infor- mation: age and gender. Next, each participant was asked to provide information on: i) which colour of cheese he/she preferred and ii) which one he/she prepared. the filled questionnaires were collected in three dedicated paper boxes, one for each cheese colour. stAtIstIcAL ANALYsIs Preference data were analysed according to chi square test (p>0.05). statistical analysis of data was carried out using the sAs/stAt sta- tistical software package version 9.3.1. (sAs In- stitute Inc., cary, UsA). rEsULts the cheese-making laboratory was visited by 1900 participants. Many questionnaires were incomplete, while some participants preferred to not give their opinion. Data from 738 partic- ipants was collected considering the gender di- mension and 5 age subgroups (1: 5-7 years old, 77 participants; 2: 8-10 years old, 142 partici- pants; 3: 11-13 years old, 182 participants; 4: 14-18 years old, 203 participants; 5: >18 years old, 134 participants); subsequently, the visual preference for one of the three coloured chees- es was considered, as reported in table 2. Data were divided in the 5 subgroups reported above, selected mainly according to different stages of cognitive development (GUINArD, 2001). In ad- dition, different food preferences and consump- tion behaviour observed in these age groups con- firmed that this type of age subdivision is rele- vant (LAUrEAtI et al., 2015). considering colour preference, regardless of age, the majority of participants preferred the white and green cheese (333 vs. 243 yellow and 162 pink; chi square=59.49; p<0.0001), which could be considered as the most “tra- ditional” because it is present on the Italian market, rather than pink or yellow cheeses, and probably seen for the first time during the laboratory activity by the most of the re- spondents. As reported in table 2, sorting by age, it could be seen that the youngest participants (between 5 and 7 years old) chose the pink cheese as their favourite, while next oldest age subgroup (8 to 10 years) preferred yellow. subjects from 11 years old and older chose the white and green cheese as their favourite, as did the overall population. this result may be associated with both the attractive effect of colours on the children and to the tendency of the youngest, as observed by Moskowitz (MOsKOWItZ, 1994), to prefer food products with a pleasing appearance. starting from the age of 11, children started to prefer, in accordance with adults, the white cheese mixed with rocket. Moreover, the youngest children’s preference can be explained by food neophobia, which is particularly high for fruits and vegetables, reach- ing its highest level between 2 and 6 years (PEL- cHAt and PLINEr, 1995; PLINEr, 1994; PLINEr and LOEWEN, 1997; LAUrEAtI et al., 2015c). It then tends to decrease when children move to- wards adolescence (ADDEssI et al., 2005), final- ly becoming relatively stable in adulthood, prob- ably because of an increased number of food ex- periences (cOOKE and WArDLE, 2005). On the other hand, the preference of older respondents for a white cheese enriched with a vegetable (rocket), may be linked to a low ac- ceptance of adults for an innovative food, while its dislike among the younger interviewees could be related to the visual presence of rocket inside cheese (rUssEL and WOrsLEY, 2008; LAUrEA- tI et al., 2015). It has already been demonstrated that tradi- tional food products have been always recog- nised by consumers as linked to a specific ge- ographical origin and highest sensory quali- ty (GUErrErO et al., 2009); as a consequence, this cheese was probably considered much more similar to product already on the Italian market compared to the pink and yellow ones. table 2 - Non-parametric statistical analysis of data to identify significant differences in preference of cheese colour by age. Data were analysed using a chi square test. Interviewees were subgrouped by age: 5-7, 8-10, 11-13, 14-18, >18 years. Preferred cheese Age subgroup (years) Yellow Pink White and green Total Chi square df P value 5-7 27 35 15 77 7.9 2 0.02 8-10 69 28 45 142 17.9 2 0.00 11−13 59 34 89 182 25.0 2 0.00 14-18 57 44 102 65 27.4 2 0.00 >18 31 21 82 134 47.9 2 0.00 All 243 162 333 738 59.5 2 0.00 Ital. J. Food Sci., vol. 27 - 2015 525 sorting by gender (table 3), no differences in preferences were seen regarding the white and green cheese, except for the oldest group (>18 years). A clear gender-related difference was, however, found for the pink and the yellow chees- es: the former seemed to be much more appre- ciated by females (all age classes except 14−18 years, but only if p<0.10 is considered as mar- ginally significant), while the latter was favoured among males (especially from 8-10, 14-18). In order to determine if this could influence the visual preference of participants, they were also questioned about the colour of the cheese they prepared; however, a significant association between cheese preferred and colour preference table 3 - Non-parametric statistical analysis of data to identify significant differences in preference of cheese colour by gen- der and age. Data were analysed using a chi square test. F= female; M=male; df=degrees of freedom. Interviewees were subgrouped by age: 5-7, 8-10, 11-13, 14-18, >18 years. Prefered cheese Gender Age subgroup (years) 5-7 8-10 11-13 14-18 >18 Total Yellow F 10 24 31 18 25 108 M 17 45 28 39 6 135 Total 27 69 59 57 31 243 Chi square 1.8 6.4 0.2 7.7 11.6 3.0 df 1 1 1 1 1 1 pvalue 0.2 0.0 0.7 0.0 0.0 0.1 Pink F 29 23 22 23 18 115 M 6 5 12 21 3 47 Total 35 28 34 44 21 162 Chi square 15.1 11.6 2.9 0.1 10.7 28.5 df 1 1 1 1 1 1 p value 0.0 0.0 0.1 0.8 0.0 0.0 White and green F 4 20 47 47 54 172 M 11 25 42 55 28 161 Total 15 45 89 102 82 333 Chi square 3.3 0.6 0.3 0.6 8.2 0.4 df 1 1 1 1 1 1 p value 0.1 0.5 0.6 0.4 0.0 0.5 for one of the three coloured cheeses was not seen, even if some significant differences were seen among the youngest consumers (table 4). In particular, when sorting by age, the sub- group from 8 to 10 years who prepared the yel- low cheese more frequently preferred this cheese over the others (26 of 52, chi square=7.5 p=0.02). Likewise, the subgroup from 5 to 7 years who prepared the pink cheese preferred it more frequently than others (12 of 21 choices, chi square=7.1 p=0.03). However, the older partic- ipants did not show a consistent trend of pre- ferred cheese over than prepared. Data from literature suggest that 7−8 expo- sures are needed to produce a learning effect table 4 - Non-parametric statistical analysis of data to assess if the colour of sample prepared could affect the overall colour preference. Data were analysed using chi square test. F= female; M=male; df=degrees of freedom. Interviewees were subgrouped by age: 5-7, 8-10, 11-13, 14-18, >18 years. Prepared chesee Age subgroup Preferred cheese (years) Yellow Pink White and green Total Chi square df P value Yellow 5-7 15 14 8 37 2.3 2 0.31 8-10 26 10 16 52 7.5 2 0.02 11-13 21 9 37 67 17.7 2 0.00 14-18 18 17 30 65 4.8 2 0.09 >18 14 9 39 62 25 2 0.00 Pink 5-7 7 12 2 21 7.1 2 0.03 8-10 19 10 9 38 4.8 2 0.09 11-13 9 12 18 39 3.2 2 0.20 14-18 22 16 37 75 9.4 2 0.01 >18 6 6 19 31 10.9 2 0.00 White and green 5-7 5 9 5 19 1.7 2 0.43 8-10 24 8 20 52 8 2 0.02 11-13 29 13 34 76 9.5 2 0.01 14-18 17 11 35 63 14.9 2 0.00 >18 11 6 24 41 12.6 2 0.00 526 Ital. J. Food Sci., vol. 27 - 2015 that can influence consumer appreciation re- garding a product (MAIEr et al., 2007). thus, it might well be that the single exposure during the cheese-making educational activity was not enough to influence children choice. cONcLUsIONs the results of this study highlight how visual preference for a food, in terms of colour, chang- es during different stages of life. Indeed, the data demonstrates how children can be influenced by food appearance and how the aspect of a prod- uct can be related to its acceptance, especially among younger individuals; in fact, the youngest participants tended to prefer intensively coloured cheese vs. the white and green version, probably because of the presence of rocket. Moreover, the cheese-making laboratory was considered to be a useful tool in order to catch and keep partici- pants’ attention, involving them in a practical ac- tivity while sharing educational and scientific in- formation related both to food processing (fresh cheese production) and sensory (visual) aspects. AKNOWLEDGEMENts the activity described in this work was made possible by the kind permission of Festival della scienza. 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