Effect of sensory education on school children’s food perception: A 2-yearfollow-up study

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Effect of sensory education on school children’s food perception: A 2-yearfollow-up study

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Effect of sensory education on school children’s food perception: A 2-yearfollow-up study

Food Quality and Preference 20 (2009) 230–240 Contents lists available at ScienceDirect Food Quality and Preference journal homepage: www.elsevier.com/locate/foodqual Effect of sensory education on school children’s food perception: A 2-year follow-up study Sari Mustonen *, Reetta Rantanen, Hely Tuorila Department of Food Technology, University of Helsinki, P.O Box 66, FI-00014 University of Helsinki, Finland a r t i c l e i n f o Article history: Received 19 October 2007 Received in revised form October 2008 Accepted October 2008 Available online 11 October 2008 Keywords: Child Sensory education Taste Smell Food perception Neophobia a b s t r a c t We studied the effect of sensory education on taste and odor awareness and food ratings in school children Second and fifth graders (n = 244, 7–11 years at the baseline) from two schools in Helsinki area participated in the study At the completion of the study at two years, the groups consisted of 96 (education, school one) and 79 (control, school two) students At baseline and in four follow-up measurements, both groups performed six tasks: (1) free odor naming (five odors), (2) taste identification (six solutions), (3) descriptive characterization of two breads, (4) ratings of the extent to which subjects paid attention to sensory properties of food, (5) willingness-to-try ratings of unfamiliar vs familiar foods and (6) aided odor naming (five odors, 10 verbal labels) Subsequently, the education group received two waves of sensory education: the first wave comprised of 10 Classes du goût lessons and the 2nd of lessons familiarizing the children with different food categories The second wave was performed only for 2/3 of the education group The educated children improved their skills in identifying tastes and odors, and characterizing foods, while no difference was seen in the performance of the control group However, effects of education were mainly observed for the younger children only Although the improvements were small and not always consistent over the study period, their general direction was encouraging: the sensory education activated children’s odor and taste perceptions and improved their ability to describe sensory properties of food Ó 2008 Elsevier Ltd All rights reserved Introduction Flavor preferences established early in life track into later childhood (Mennella, Pepino, & Reed, 2005) The information concerning children’s use of their senses of taste and smell, and learning their preferences, is still rather scarce It is, however, well known that children like sweet-tasting foods and beverages Birch (1979) has found that children under five years base their food preferences on two dimensions: sweetness and familiarity Thus, children’s food preferences and dietary choices might be driven primarily by sensory qualities of food, whereas adults tend to be more concerned with the nutritional and health qualities of the diet (Drewnowski, 2000; Nicklaus, Boggio, Chabanet, & Issanchou, 2004) A common belief is that children are more sensitive to smell and taste stimuli than adults, although researchers have not been able to show any difference in sensitivity (Guinard, 2001) The belief may be a misconception due to children’s tendency not to accept new or unfamiliar foods, called neophobia Neophobia is a protective mechanism preventing animals and humans from eating what could be harmful to them At the same time it leads humans to choose the familiar and safe food instead of new and unfamiliar, * Corresponding author Present address: Valio Ltd, R&D, P.O Box 30, FI-00039 Valio, Finland Tel.: +358 10 381 3047; fax: +358 10 381 3372 E-mail address: sari.mustonen@valio.fi (S Mustonen) 0950-3293/$ - see front matter Ó 2008 Elsevier Ltd All rights reserved doi:10.1016/j.foodqual.2008.10.003 potentially harmful food Neophobia appears in all age groups, but the strength of neophobia varies between individuals (Pliner & Salvy, 2006) In children, strong neophobia is probably due to the lack of earlier experiences on different foods (Birch, 1999), as exposures to a large variety of unfamiliar foods can reduce the neophobic reactions towards other novel, at least similar, foods (Birch, Gunder, Grimm-Thomas, & Laing, 1998) Also Pliner, Pelchat, and Grabski (1993) have shown that exposing humans to novel foods can reduce their food neophobia Thus, humans tend to widen their preferences also to initially rejected foods, but they need a compelling force to so According to Birch (1999), and Popper and Kroll (2005), social influence may also help to reduce neophobia, especially in children The present paper describes a sensory education program that provides children social interaction with their peers as well as increases their awareness of and curiosity towards foods Sensory education may act as the compelling force needed to increase willingness to taste unfamiliar foods In industrialized countries, changing society and busy lifestyles drive people to more convenient and, at the same time, to monotonous food choices and increased use of snack foods (Jahns, Siega-Riz, & Popkin, 2001) The current lifestyle also acts as a main barrier to planning regular and balanced meals in the family: parents are busy and the need for convenience drives them more and more often to feed their children with easy options like fast food or snacks (Gillman et al., 2000; Haapalahti, Mykkänen, Tikkanen, & 231 S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 Kokkonen, 2003) This kind of a change does not promote the adoption of new food experiences (Carruth et al., 1998; NeumarkSztainer, Hannan, Story, Croll, & Perry, 2003) Instead, it leads children and adolescents to repeatedly choose the same and familiar foods, causing monotonous and unhealthy diet in the long run (Veugelers & Fitzgerald, 2005) Because of this blunting trend, the future generation may be unable to demand high quality or to have the courage to try new, exotic foods Therefore, it is important to invent and develop new ways to encourage children to try different foods and pay attention to the quality of foods This may eventually have beneficial effects on children’s diets in terms of greater variety and better quality of food In France, Puisais and Pierre (1987) developed and described ‘‘taste lessons” (Classes du goût) This education program for school children has been used in several European countries, e.g in Sweden (Hagman & Algotson, 2000) The program aims to teach young children to become well-informed consumers with awareness of the quality and differentiation of foods through their smells, textures and tastes Children’s awareness is developed by awakening their interest and curiosity towards foods by exercising their senses Although widely used, the evidence of the impact of the education program is still rather scarce To date, no systematic research on the effects have been available in scientific literature Ton Nu (1995) has reported that, as a result of the program, children’s interest in food quality increased and their ability to describe sensory properties of food improved compared to the control group, but no measurements were conducted at the baseline level Thus, development in sensory awareness over time could not be proven Sune, Lacroix, and de Kermanec (2002) compared children who attended the Classes du goût program with their non-trained peers and adults in sensory characterization of chocolate and found that despite the education, children described the chocolate in their own way and adults in their own way In Finland, we started a 2-year follow-up study with school children, representing two age groups (7–8 and 10–11 years), to track the development of chemosensory awareness and food-related perceptions influenced by the program One-half of children received up to two waves of taste lessons (first, a Finnish application of Classes du goût program and second, activating lessons on main food categories) and another half performing baseline and followup measurements only Two age groups were included to the study to examine whether the possible effect of education would depend on the age at which the lessons are attended The education group was further divided into two subgroups, as the second wave of education was given only to 2/3 of the education group, to examine whether the children would benefit from a prolonged education The effects of the sensory education were studied with (1) sensory tests conducted in the laboratory and (2) background questionnaires on subjects’ food behavior that were sent to parents three times during the follow-up period This paper describes the results of sensory measurements at the baseline and in the four follow-up measurements, all conducted in the laboratory during two years of time The first education wave was expected to increase sensory awareness, improve food description skills and increase the willingness to taste unfamiliar foods Due to the nature of the lessons in the second education wave, it was expected to maintain the interest in chemosensory perception achieved during the first wave, and increase the interest in trying unfamiliar foods Materials and methods 2.1 Development and selection of the sensory instruments A preliminary study was carried out during the autumn 2004 to develop and select the sensory instruments for the proper study Three classes of third graders and three classes of fourth graders participated in the preliminary study, testing different sensory measurements (odor naming, taste identification, descriptive tasks, etc) The tests were conducted twice, and between the sessions one group of the children (N = 35) received a lesson on the sense of taste, another group (N = 34) received a lesson on the sense of smell and the third group (N = 40) received no lesson Children participating in the pilot taste lesson showed slight improvement in their taste identification No improvement was seen in the odor naming abilities of the group receiving the olfactory lesson, but it was expected that after a profound sensory education on tastes and odors the effects would emerge The descriptive abilities were expected to improve due to the sensory education that included descriptive tasks, although after the pilot lessons the only effect was a decrease in the number of preference-related descriptors The willingness to taste unfamiliar foods was expected to increase due to the tasting experiences and the overall increase of knowledge on different foods during the sensory education The tests that seemed to have potential in showing education effects in the preliminary study were chosen to the proper study (described in detail below) 2.2 Subjects In the proper study, 244 students (aged 7–11 years) from two primary schools in Helsinki were recruited The schools chosen were approximately similar in size and their students had more or less the same level of socio-economical background (between middle and high) Of the students, 175 participated in all followup measurements, and are therefore included in the data analyses In the beginning of the study, they were students at the second (7– years) and fifth (10–11 years) grades in Viikki Teacher Education School at Helsinki University (education group, n = 96) and Puistola Primary School (control group, n = 79) The students from the firstmentioned school were chosen to be the education group for practical reasons, as sensory lessons fitted into their curriculum The profiles of the subjects (grades and gender distribution) are shown in Table The drop-outs in the last follow-up measurement were due to some of the students in the older group moving on to an upper level of comprehensive school, and thus to a different system or even to a new school 2.3 Overview of the proper study At baseline (January 2005), both groups performed sensory tests, and subsequently, one group (education group) participated in sensory education The tests were conducted four times during the two years’ period: after the first education wave (May 2005), before and after the second education wave (January and May 2006, respectively) and finally in January–February 2007 (Fig 1) Additionally, a questionnaire was sent to the parents three times during the follow-up period (results reported elsewhere) The study protocol followed the ethical principles of sensory testing in our laboratory, approved by the ethical committee of Table The study population In the beginning of the study the children were 8-year-old (second graders) and 11-year-old (fifth graders) Group and grade Education 2nd–4th 5th–7th Control 2nd–4th 5th–7th Total N boys/girls N (2005–2006) baseline and 1st–3rd follow-ups N (2007) 4th follow-up 19/22 30/25 41 55 38 38 12/22 26/19 87/88 34 45 175 31 30 137 232 S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 October-December 2004 PILOT TESTING RECRUITMENT Informed consent (parents) January 2005 BASELINE MEASUREMENT Sensory instruments Questionnaire to parents 1st WAVE OF SENSORY EDUCATION April-May 2005 1st FOLLOW-UP MEASUREMENT Sensory instruments Questionnaire to parents January 2006 2nd FOLLOW-UP MEASUREMENT Sensory instruments 2nd WAVE OF SENSORY EDUCATION (for 2/3 of the education group) May 2006 3rd FOLLOW-UP MEASUREMENT Sensory instruments Questionnaire to parents January 2007 4th FOLLOW-UP MEASUREMENT Sensory instruments Fig Flow chart of the experimental procedure of the study the Faculty of Agriculture and Forestry An additional approval was applied as the subjects were minors (under 18 years of age) The parents signed an informed consent before the study began The subjects themselves gave a verbal assent to participate 2.4 Laboratory sessions The measurements (lasting approximately 1.5 h) were conducted in the sensory laboratory of the University of Helsinki (except for the last session for the older group, which was performed in the school auditoria) All measurements were made during the school day (9 a.m to p.m.) One class at a time (N = 17–28) came to the laboratory with a teacher and performed the tasks in a given order in ten sensory booths or at a round table with screens preventing visual interaction between the ten seats During the session, the places were switched for each task so that each subject was placed in both the booths and at the round table In each session, the subjects performed six tasks in the following order: (1) pleasantness ratings, intensity ratings, and free naming of five odor stimuli; (2) taste identification of six aqueous solutions (sweet, salty, bitter, sour, umami, and water); (3) descriptive characterization of two breads; (4) ratings of the extent to which subjects paid attention to sensory properties of food; (5) willingness to taste unfamiliar (five in the baseline and first follow-up, seven in the second-final follow-ups) and familiar (seven) foods (the procedure adapted from that by Pliner, 1994), and (6) aided odor naming (five odors, list of 10 verbal labels provided) Before every task, the sub- jects were familiarized with the evaluation forms and scales The tasks are described in detail below After the sessions, the subjects were rewarded with small food gifts (lollipops, xylitol chewing gums etc.), and in the end of the final session, they were invited to make and consume their favorite ice cream portions using a selection of ice creams, jam, sauce, nonpareils, wafer, and decorations 2.4.1 Sensory instruments 2.4.1.1 Free odor naming and ratings for pleasantness and intensity (Task 1) The test included five aqueous aroma solutions: strawberry, carrot, vinegar, cardamom, and vanilla (Table 2) The samples (10 ml each) were presented in small brown glass vials coded with five letters (Z, D, F, X, G) and the presentation order was randomized in five different ways for practical reasons The same five orders were used for each follow-up, without controlling the order individually for each child The subjects also rated the pleasantness and intensity of each sample The pleasantness was rated using seven categories (1 = bad and = good), extreme ends supported by facial symbols, and the intensity was rated using seven categories (1 = weak, = strong) The purpose of these ratings was to maximize the attention paid to each sample After ratings, the subjects were asked to name each odor If uncertain, they were asked to guess Table shows the mean ratings of pleasantness and intensity given to the aroma solutions at the baseline measurement 2.4.1.2 Taste identification (Task 2) The test included aqueous solutions of five taste stimuli (sweet, salty, sour, bitter, umami) and water (Table 4) The solutions (approximately 15 ml each) were presented in white plastic cups coded from to The presentation order was randomized in six different ways The labels of the tastes were listed, and the subjects ticked the box they thought was the correct answer Umami was described as ‘‘umami (meaty)” The subjects compared the solution to plain tap water when they tried to identify the taste In case they did not identify the taste, they were asked to guess 2.4.1.3 Descriptive characterization of two breads (Task 3) The subjects were presented with two bread samples in each session All breads were commercial Finnish breads (brand names in parentheses below) and represented different sensory properties At the baseline they were wheat toast (Reilu, Fazer Bakeries) and a wholeTable Aqueous aroma solutions (dissolved in tap water) used in the free and aided odor naming Free odor naming (Task 1) Aided odor naming (Task 6) Aroma/Ingredient Concentration (%, w/v) Aroma/Ingredient Concentration (%, w/v) Vanilla1 Cardamom1 Strawberry aroma1 Carrot2 (powder) Vinegar3 0.4 0.1 0.15 0.5 33.3 Pineapple2 Cocoa1 Lemon1 Onion2 (powder) Peppermint1 0.3 0.4 0.02 0.4 0.15 Manufacturers: (1) Quest International, The Netherlands; (2) Givaudan, Switzerland; (3) Rajamäki, Finland Table Mean ratings (SD) of pleasantness and intensity of the aroma solutions in the free odor naming at the baseline (Task 1) Aroma/ingredient Pleasantness (scale 1–7) Intensity (scale 1–7) Vanilla Cardamom Strawberry Carrot Vinegar 5.3 4.8 4.5 3.3 2.1 4.0 4.3 4.6 4.6 5.5 (1.8) (1.7) (1.9) (1.8) (1.7) (1.6) (1.6) (1.5) (1.7) (1.7) S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 Table Aqueous taste solutions (dissolved in tap water) used in the taste identification test (Task 2) 233 The task was not performed by the older group in the last follow-up session, as that session had a limited space and time frame that required adjustments Taste identification Taste compound Sucrose (sweet) NaCl (salty)2 Citric acid (sour)2 Caffeine (bitter)2 Monosodium glutamate (umami)3 Concentration (%, w/v) 0.2 0.04 0.04 0.3 Manufacturers: (1) Dan Sukker, Finland; (2) Fluka Chemicals, Germany; (3) Merck, Germany meal rye bread (Real, Fazer Bakeries Oululainen); in the first follow-up regular rye bread (Ruispuikula, Fazer Bakeries) and a sweet loaf (Setsuuri, Fazer Bakeries); in the second follow-up dark loaf (Maalahden limppu, Malax Limpan Ltd.) and grainy wheat toast (Jyväinen IsoPaahto, Vaasan and Vaasan Oy); in the third followup two premium breads, garlicky cheese ciabatta (Artesaani, Primula Oy) and grainy rye bread (Artesaani, Primula Oy); and in the last follow-up measurement the subjects described the same breads that were presented in the baseline measurement The subjects described separately the appearance, smell, taste and texture/ mouthfeel of both samples They were told to avoid words relating to preference They rinsed their mouths with tap water between the samples 2.4.1.4 Ratings of the extent to which subjects paid attention to sensory properties of food (Task 4) In this task, the subjects rated the extent to which they paid attention to sensory properties (appearance, odor, taste, texture) of food (scale: = not at all, = slightly, = quite much, = very much) 2.4.1.5 Willingness to taste unfamiliar vs familiar foods (Task 5) The subjects were presented with 12 (baseline and first follow-up) or 14 (other measurements) pictures of familiar (seven) and unfamiliar foods (five/seven) in color The task was to identify which food was in the picture The subjects then got another booklet in which the same foods were presented in black and white, with the name of the food in the upper edge of each picture They were asked to reply yes/no to the following questions: (1) ‘‘Have you ever seen this food before?” (2) ‘‘Have you ever tasted this food before?” and (3) ‘‘Would you like to taste this food?” The first two questions were used to check whether the foods actually were unfamiliar for the children Although the results were not analyzed individually, the distributions strongly suggested that the foods expected to be unfamiliar to the children actually were unfamiliar The familiar foods (rye bread, ice cream, blueberry, meat balls, Edam cheese, carrot, chocolate cookie) were the same for each follow-up point, but the unfamiliar foods were changed At the baseline and at the first follow-up, the unfamiliar foods were goat cheese, lychee, sun-dried tomatoes, Naan bread, and frog legs At the second and third follow-up they were: squid, sheep milk cheese, carambola, artichoke, couscous, kidney pie, and shiitake At the last follow-up they were: oyster, Camembert, pitahaya, avocado, sweet potato, reindeer tongue aspic, and endive Even if the two successive follow-up measurements had the same pictures of the unfamiliar foods, the familiarity status of each food did not change as we instructed the children to answer ‘‘yes” only if they had seen the food for real, not in a picture The food pictures were kept similar for two successive sessions to make the comparison reliable If the foods had been changed every time, the unfamiliarity may have changed because of the foods chosen, and not for the reasons we were measuring Yet, we had to change some of the foods a few times during the study, to avoid familiarity and boredom with the same foods 2.4.1.6 Aided odor naming (Task 6) The test included five aqueous aroma solutions: cocoa, pineapple, lemon, onion, and peppermint (Table 2) The aroma samples (10 ml each) were presented in small brown glass vials coded with five letters (H, J, N, L, R) and the presentation order was randomized in five different ways The subjects were asked to connect the odor (letter codes in the evaluation form) to the correct label They could choose from 10 labels, of which five were correct The labels (correct ones marked with bold) were: black pepper, banana, cocoa, pineapple, onion, cinnamon, apple, orange, lemon, peppermint 2.5 Sensory education program The first wave of sensory education was held between the baseline and the first follow-up measurement in February–April 2005 (Fig 1) It comprised of nine sensory lessons and a restaurant visit The lessons followed the principles of the program ‘‘Classes du goût” (Puisais & Pierre, 1987), but modifications were made to the contents and reference materials to suit better to the Finnish environment and the current scientific information on the issues dealt with Each lesson comprised of a short lecture (adapted to be suitable for children) on the topic, discussion and practical exercises The lessons (approximately 1.5 h each) took place at school Two experimenters responsible for the measurements and an assistant gave the lessons each week The contents of the lessons are described in Appendix The second wave of sensory education took place in February– April 2006 (Fig 1), between the second and third follow-up measurement, and consisted of five lessons related to a specific food category at a time (dairy, cereal or meat) Only two school classes out of three from the education group participated in the second education wave The second wave was performed in collaboration with Finnish food industry The personnel of the collaborating food companies, all with an academic degree in food science, gave the lessons Otherwise the practices were similar to the first wave In spite of the effort, no fruit and vegetable supplier nor a fish supplier participated in the second wave of education Basically the lessons were similar to the first wave, with a short introduction to the topic and practical exercises The contents of the lessons are described in Appendix In both education waves, the practical exercises and activation of senses played a major role 2.6 Data analysis The ratings of the two subgroups (one wave or two waves) of the education group did not differ, and thus, the education group was pooled to include all children who received education Repeated measures of ANOVA (between subjects: treatment education/control and age group; within-subject: session) were used to examine the effect of age group and sensory education on the performance in each of the sensory tasks In the bread description task, only the baseline and final follow-up measurement were included in the analysis, as the results in between were not comparable because different breads were used every time The score of the description task was a sum of descriptive words for appearance, smell, taste and texture/mouthfeel (hedonic terms excluded) The effect of education was expected to appear as an interaction of education  session Significant interactions between different sessions (within-subject contrasts) are reported, when appropriate The two age groups were analyzed also separately when a trend for age group difference was observed (main effect of age group or interaction of education  age group  session) 234 S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 Table Free naming of odors (Task 1): descriptions receiving 0.5 score Odor Close association Strawberry Candy, cough medicinea, chewing gum, raspberry, lemonade, cherry, fruit, juice, marmalade Potato, root vegetable, earth, beetroot, rutabaga, pea, vegetable, zucchini Wine, salad dressing, alcohol, mustard, pickled cucumber Bun (pulla), mulled wine (glögi), cinnamon, spice, gingerbread, doughnut, ginger Chocolate, caramel, toffee, honey, apple sodab, marshmallow, candy, ice cream, pastry, syrup, cake Carrot Vinegar Cardamom Vanilla a b In Finland, children’s cough medicine is often strawberry-flavored Finnish apple soda is flavored with vanilla In the free odor naming task, the subjects got one score for each correctly named odor If they could name a source of an odor closely associated with the exact odor they got a score 0.5 Thus, the total score of the odor naming task (0–5) for each subject was the sum of correctly named and closely associated odors The accepted associations are shown in Table The score of the aided odor naming task was a sum of correctly named odors, thus it could vary from zero to five (no half scores given) The score for willingness ratio for trying unfamiliar vs familiar foods was calculated by dividing the number of affirmative answers given to the question ‘‘Are you willing to try this food?” for the unfamiliar foods by the corresponding number for the familiar foods Higher scores reflected greater willingness to taste unfamiliar foods To correct the uneven ratio of unfamiliar foods and familiar foods in the baseline and 1st follow-up, the sum of unfamiliar foods tasted in those two measurements were multiplied by 7/5, thus 1.4 Scores lower than reflected a situation in which the child was willing to taste a greater number of the familiar foods than the unfamiliar foods, and scores higher than the opposite situation If a child answered ‘‘No” to all familiar foods the denominator is equal to 0, thus the ratio is undefined (infinite) However, none of the children in the present study answered ‘‘No” to all familiar foods A score equal to1 meant that a child was equally willing to taste the unfamiliar and familiar foods For five unfamiliar and seven familiar foods, the range of scores was 0– 2.3 and for seven unfamiliar and seven familiar foods, 0–2, respectively Subtractions between positive answers to the question ‘‘Have you ever seen this food” for unfamiliar foods in the first follow-up and at the baseline (five foods), and between third and second follow-up (seven foods) were calculated for each child and subsequently, the subtractions of the control group and education group were compared using univariate ANOVA To check whether an improvement in one task was related to an improvement in another task a ‘‘score evolution difference” was calculated for each task and each subject separately The individual improvement in one task leading to improvement in other task were reported for the three chemosensory tests, i.e free odor naming, aided odor naming, and taste identification tasks for the education group The calculations were done manually The score evolution differences of the tasks were cross-tabulated and Pearson’s correlations between the score evolution differences of the tasks were calculated, but no significant results, even trends were found and therefore these results have not been included in the result section Results 3.1 The effect of sensory education on performance in the two age groups 3.1.1 Free (Task 1) and aided (Task 6) odor naming In the free odor naming task, children were able to correctly name an average of one odor out of five only The median and mode for both age groups were and However, in some cases they gave a name that was closely associated to the exact odor The sensory education improved the free odor naming of both the younger age group, 2nd–4th graders [interaction education  session F(4, 62) = 3.90, p = 0.007] and the older group, 5th–7th graders [interaction education  session F(4, 60) = 2.80, p = 0.034] with the exception of the second follow-up measurement, in which the performance got poorer compared with the earlier measurement The free odor naming of the control group stayed approximately at the same level during the whole study period in both age groups (Fig 2a) In the aided odor naming, approximately three odors out of five were identified The median and mode for the young group were and For the older group, the corresponding scores were and No education effect was found Instead, in the younger age group, the control group performed better than the education group in the last two follow-up measurements [interaction of education  session between 2nd and 3rd follow-up F(1,65) = 4.66, p = 0.035] In the older age group, the performance of the control group impaired after the third follow-up, while the number of correct responses of the education group stayed at the baseline level after the 1st education wave, but improved in the second follow-up measurement [interaction of education  session between 2nd and 3rd followup F(1, 66)=3.93, p = 0.052; between 3rd and 4th follow-up F(1,66)=5.31, p = 0.024] (Fig 2b) 3.1.2 Taste identification (Task 2) Fig shows the mean performance of the children in the taste identification task [interaction of education x session F(4, 260) = 2.72, p = 0.030] At first, the performance of the younger age group was improved: the education group identified more tastes after the first education period than at the baseline, while no difference was seen in the performance of the control group [interaction of education x session between baseline and 1st follow-up F(1, 65) = 11.76, p = 0.001] In the following sessions, no differences between the groups in the taste identification task were found The education did not have a significant effect on taste identification performance of the older age group (p = 0.322) The percentage of correctly identified tastes (both age groups combined) in the baseline measurement are shown in Fig 4a In all sessions, the easiest taste to identify was sweet (of all subjects, 78% identified), followed by salty (60% correct identifications) and sour (51% correct identifications) Bitter and umami proved to be the most difficult, with identification percentages 24% and 20%, respectively Fig 4b shows that sensory education improved the identification of the most difficult taste, umami, in the younger age group [interaction of education  session F(2, 131) = 3.07, p = 0.05] whose identification rate at the baseline was 8.3% and in the final measurement 30.5% For the older children in the education group, the corresponding figures were 29.1% and 37.3%, respectively The change in the number of correct identifications was not significant for the older group For bitter taste, the increase in identification percentage was not significant (p = 0.59) 3.1.3 Descriptive characterization of two breads (Task 3) The number of descriptive words (preference-related words excluded) for breads increased in the younger children of the education group during the study period, while for the control group the number of words was approximately the same for the whole study period [interaction of education  session between baseline and final follow-up F(1, 67) = 6.67, p = 0.012] (Fig 5) In the older children, both the education group and the control group, the number of descriptive words decreased from baseline to the final follow-up measurement [main effect of session F(1, 63) = 22.07, p < 0.001] Overall, the number for descriptive words for 235 2.-4 graders 5.-7 graders 2.-4 graders follow up follow up follow up follow up follow up follow up follow up follow up Baseline follow up follow up follow up Baseline Baseline follow up Education (N=96) 3 follow up Control (N=79) follow up Education (N=96) Baseline Control (N=79) follow up Correctly identified odors follow up Correctly named odors S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 5.-7 graders sessions For the five unfamiliar foods at the baseline and in the 1st follow-up, the mean change in the education group was 0.79 The change was mostly due to one food, lychee, which was present in one of the lessons in the first education wave For the control group the corresponding change was 0.56 (effect of education, p = 0.24) Mean change in the number of positive answers between 2nd and 3rd follow-up was 0.14 for the education group and 0.28 for the control group (effect of education, p = 0.72) Control (N=79) Education (N=96) 2.-4 graders followup followup followup Baseline followup followup followup followup followup Baseline Correctly identified tastes Fig (a) Free naming of odors, (b) aided naming of odors: mean number (+SEM) of correctly named (or in free naming task also closely associated) odors for the education group and the control group (2nd–4th and 5th–7th graders separately) in the baseline and in the four follow-up measurements (maximum score 5) 5.-7 graders Fig Taste identification: Mean number (+SEM) of correct responses of the education group and the control group (2nd–4th and 5th–7th graders separately) in the baseline and in the four follow-up measurements (maximum score 5) breads was higher in the older children than in the younger children [main effect of age group F(1, 130) = 48.77, p < 0.001] 3.1.4 Ratings of the extent to which subjects paid attention to sensory properties of food (Task 4) Fig shows that children rated themselves to pay the most attention to taste and least attention to texture of food in both age groups The only evolution due to sensory education during the study period was seen as a slight trend in the younger group to pay more attention to texture of food compared with the control group [interaction of education  session F(4, 228) = 1.98, p = 0.086] In the younger children, the education group rated themselves overall to pay more attention to appearance [main effect of education F(1, 58) = 6.02, p = 0.017], odor [F = 6.15, p = 0.016], and taste [F = 4.81, p = 0.032] (means over all sessions), although no difference was seen at the baseline [ main effect of education F(4, 69) = 0.64, p = 0.633] In the older age group, no difference between the education group and the control group was found in any of the ratings of attention (Fig 6) 3.1.5 Willingness to try unfamiliar vs familiar foods (Task 5) The willingness to taste unfamiliar foods did not change significantly in either the young group [interaction of education  session F(3, 67) = 0.87, p = 0.46] or in the old group [interaction of education  session F(3, 87) = 0.70, p = 0.55] (Fig 7) The number of positive answers to the question ‘‘Have you ever seen this food before” did not change significantly between the 3.1.6 Evolution of performance in the three tests measuring chemosensory awareness Of the education group, only 26 children in both age groups improved in their performance in the free odor naming and 25 children in the taste identification during the study In the aided odor naming test, 11 children in the younger group and 12 children in the older group improved their performance during the study In each group, half of them were girls and half of them were boys In the education group, four children of the young group improved in all three tests (free and aided odor naming and taste identification) The corresponding figure for the older group was two Improvement in both the free odor naming and the aided odor naming tasks, but not in taste identification was seen in three children of the young group and six children of the old group Four children of the young group and one of the old group improved their performance in both aided odor naming and in taste identification Finally, improvement in free odor naming and in taste identification was seen in ten children of the young group and 11 children of the old group Discussion The free naming of odors proved to be a difficult task for the school children That is not surprising, as according to de Wijk and Cain (1994), the task is very difficult also for adults In their study, adults identified approximately two out of the six odors presented, if no cues were given In the cued situation, the corresponding figure was five odors out of six (De Wijk & Cain, 1994) In the present study, the identification score was at the baseline approximately (one odor out of five identified), thus slightly lower than for adults in de Wijk and Cain study Lehrner, Glück, and Laska (1999) have concluded that children possess equal olfactory sensitivity compared with adults, but their odor identification is limited due to limitations in linguistic capabilities and familiarity of odorants Although the free odor naming task in the present study was difficult, improvement in the performance was observed in the education group after the sensory education period The improve- 236 S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 100 Education (N=96) Control (N=79) 80 60 40 20 Correct identifications (%) Correct identifications (%) 100 Control (N=79) 60 40 20 Baseline follow-up Final follow-up Sweet Salty Sour Bitter Education (N=96) 80 Umami Baseline 2.-4 graders follow-up Final follow-up 5.-7 graders Baseline Final follow-up Baseline 2.-4 graders Final follow-up Education (N=96) 2.-4 graders Texture Taste Odor Appearance Texture Taste Odor Appearance Attention to sensory properties 2.-3 graders 5.-7 graders Fig Mean number (+SEM) of sensory descriptions per session (preferencerelated words excluded) of the bread samples by the education group and the control group (2nd–4th and 5th–7th graders separately) in the baseline and in the final follow-up measurement Control (N=79) 0.2 5.-7 graders Fig Mean ratings (+SEM) of attention paid to sensory properties of food by the education group and the control group (2nd–4th and 5th–7th graders separately), over all follow-up points ment was most likely due to familiarization with odors during the education and to the improved ability to recall odor names Lumeng, Zuckerman, Cardinal, and Kaciroti (2005) demonstrated an association between language development and flavor recall in followup 0.4 followup 0.6 followup 10 Education (N=96) Baseline 12 Control (N=79) 0.8 followup 14 followup Control (N=79) followup Education (N=96) Baseline Mean number of descriptive words 16 Willingness ratio unfamiliar /familiar foods Fig (a) Percentage of correctly identified tastes by subjects in the control group and education group in the baseline measurement, age groups pooled, (b) percentage of correct identifications of umami taste for the education group and the control group (2nd–4th and 5th–7th graders separately) in the baseline, 1st and final follow-up measurement (Means and SEM) 5.-6 graders Fig The ratio of willingness to try unfamiliar vs familiar foods by the education group and the control group (2nd–3rd and 5th–6th graders separately) in the baseline and in the three follow-up measurements (the older age group did not perform this task in the final follow-up measurement, and therefore the final follow-up point is excluded) See Data analysis for the calculation of the ratio preschool-aged children: accurate and consistent labeling of flavor improved recall for a variety of stimuli In the present study, the education included labeling of different types of stimuli which possibly led to improved ability to name odors Yet, Cain, de Wijk, Lulejian, Schiet, and See (1998) showed that general training of odor identification does not improve identification of odors that are not in the training set In the present study, the same odorants were used for each session, thus the possible improvement in the ability to name odors not presented before remains open Aided odor naming turned out to be a relatively easy task and no benefit of sensory education was observed Although the scores did not reach maximum at the baseline, the effect of sensory education was assumingly not strong enough to improve an already good performance Furthermore, lemon odor seemed to be more difficult to identify than the others (data not shown), suggesting that the lemon aroma used was not a well representative of the odor Taste identification of the younger children improved after the first wave of education period and remained more or less at the achieved level throughout the study period In the older group, no clear improvement was observed The most difficult taste to identify was umami: This is in line with our earlier findings (Oerlemans, Mustonen, Esselström, & Tuorila, 2006), measuring taste identification of a partially separate group of 8-, 9-, 10- and 11year-old children (n = 348) Although approximately one-third of S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 the respondents of the present study were included in the data by Oerlemans et al., some comparison can still be made In the study by Oerlemans et al., 82, 66, 52, 27 and 23% of children identified sweet, salty, sour, bitter, and umami tastes, and age groups performed significantly differently only in the identification of salty taste (8-year-old did not reach the level of the other age groups) The overall improvement of the taste identification performance of the younger education group was mostly due to improved identification of umami Bitter was also a difficult taste to identify at the baseline, but the identification performance of it did not improve during the study One reason for the improvement of the identification of umami, but not of bitter might be that umami was overall a new term for almost all of the children and the curiosity towards this new taste may thus have improved the identification rate In the sensory characterization of breads, older children used a greater number of words than did the younger This is in line with the consistent finding in product evaluation, as younger children (3–7 years old) use fewer attributes or dimensions in comparing products and forming preferences than older children (11–16 years old) (Roedder, 1999) The two comparable sessions using the same breads – the first and the last – showed that in the younger education group, the number of descriptive words increased significantly Earlier studies have shown that verbalization of sensory experiences is supported by taste lessons in 12year-old school children (Jonsson, Ekström, & Gustafsson, 2005) In contrast, Sune et al (2002) found that despite attending the taste lessons (Classes du goût program), children described chocolate in their own way that was different from that of adults In the present study, the number of words of the older children of the education group was, unexpectedly, at its lowest in the last session and for the control group the number was smaller than at the baseline This may partly be due to the incipient puberty: in the final follow-up measurement, the students, especially in the education group, were restless while performing the description task Children reported to pay attention to taste of food while eating, rather than to other sensory modalities Children at ages 7–11 are categorized to be at the analytical stage of socialization as consumers (Roedder, 1999), thus they are able to orientate features requiring special attention (e.g taste) of a product rather than immediately observable perceptual features (e.g appearance) The latter is typical for perceptual stage (ages 3–7 years) Taste remained as the most important attribute for all subjects The overall ratings show that the younger group paid more attention to appearance, odor and taste of food than the control group during the study, although the groups did not differ in their ratings at the baseline Hence, education in general seemed to activate the younger children to pay more attention to these attributes in food The ratio of willingness to taste unfamiliar to familiar foods was approximately 0.6 at the baseline for both age groups, which was slightly higher than the corresponding figure of Canadian children (0.5) in Pliner’s study (1994) The results are not fully comparable, as in Pliner’s study, children were supposed to actually taste the foods that they reported to be willing to taste, while in the present study the willingness to taste was rated based on photographs of foods In the present study, the willingness to taste unfamiliar foods did not change significantly, although the mean values tended to decrease The result suggests that sensory education does not affect the willingness to taste unfamiliar foods Yet, Reverdy, Chesnel, Schlich, Köster, and Lange (2008) studied children aged 8–10 years and found that declarative food neophobia of the education group decreased significantly and the willingness to taste novel food seemed to increase compared to the control group However, the effect was only temporary, disappearing after 10 months of the education period 237 Looking only at the results of the baseline and the first followup measurement, it seems that willingness to taste unfamiliar foods tended to increase in the older age group after the first education wave, while the effect was opposite for the younger group This age difference was also observed by Loewen and Pliner (1999) who found that the exposure to novel foods decreased willingness to taste novel foods in 7–9-year-old children, while it increased willingness to taste novel foods in 10–12-year-old children An age effect may thus exist, and the increase in willingness to taste unfamiliar foods may result from a certain developmental process However, the procedure may also have played a role: the number of follow-up measurements was rather high and may have caused a learning effect in the control group The sensory experiences provided in the follow-up measurements, increased children’s awareness of food odors and flavors, and thus may also have increased their interest in new food experiences The result may have been different, if tasting of the foods rather than photographs had been included In Pliner’s (1994) original willingness ratio as neophobia measurement, children were supposed to actually taste the foods that they reported to be willing to taste, increasing the validity of the measurement The education effect was not quite stable This is in line with results by Reverdy et al (2008), who found the education-induced increase of willingness to taste novel foods in children disappearing ten months after the education period In the present study, in the tests measuring chemosensory awareness (odor naming and taste identification), the effect was at its strongest right after the education period and the performance did not improve, but even impaired later In the free odor naming task, the performance got worse in the second follow-up measurement, while the performance was at its highest in the final measurement A similar trend could be observed for the taste identification task in the younger age group, but not for other tasks for either age group The second education wave did not affect the performance in the laboratory tasks, perhaps because the education concentrated on fairly general matters rather than on specific chemosensory performance or skills In a deeper exploration of the reasons for the rather weak effect of education we observed that the sensory education affected significantly only a limited number of the children in the tests measuring chemosensory awareness The groups with a greater evolution in their performance were equal in their gender distribution and heterogeneous in terms of the class they belonged Thus, no clear reason can be found for that these children evolved in their performance more than the others Overall, the education had hardly any effects on the performance and perceptions of the older children, compared to the young ones This could partly be explained by the incipient puberty: as the sensory education was more informal than the school curriculum in general, the older children may have related to measurements carelessly Also, the large number of follow-up measurements with similar tests may have decreased their motivation, especially when no feedback on one’s performance was given during the study period In line with this, Spinath and Spinath (2005) found in their longitudinal study over two years that learning motivation of school children decrease over the elementary school years The present study shows that sensory education has potential in activating children’s chemosensory awareness and improving their attention towards foods and also skills to describe foods The effects may not be dramatically large, but they exist The effects were stronger in the younger children, suggesting that a suitable time to start the sensory education program and getting the most of it could be at the age of eight years or even earlier In addition to the measurable effects, the sensory education appealed both to children and school staff It provided a positive and enjoyable way of highlighting food-related sensory issues in the school, as seen in focus group interviews of children and parents (Salo, 238 S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 2007), and teachers (Huotilainen, 2005) The improved skills and interest in food and eating is not necessarily a measurable effect, but such development broadens the perspectives to foods and eating and provides tools in coping with food choices At its best, sensory education encourages children to try different foods and pay attention to food quality, which may lead to more healthy and balanced eating habits Interactions of taste and smell (flavor) Acknowledgements Sense of sight The authors thank research technician Kaisu Taskila for her skillful help in laboratory measurements and lessons, and Dr Anna Huotilainen for conducting the lessons in the first education wave The representatives of the Finnish companies Valio Ltd., Raisio Ltd., Fazer Bakeries and Biofincon Ltd., and Mr Olavi Törmä, MSc, from the meat pilot plant of the Department of Food Technology are thanked for contributions to second education wave The anonymous reviewers are thanked for their great effort that helped us improve the paper The interest and encouragement of the SAPERE group (http://www.sapere-asso.eu), headed by Mr Roelof Huurneman, is acknowledged This study was funded by the research program of Ministry of Agriculture and Forestry, Finnish Innovation Fund (Sitra) and by Emil Aaltonen Foundation, Finland Sense of touch and texture of food Appendix A Appendix The first wave of the sensory education program Topic Contents of the lesson (practical exercises) Introduction to senses -introduction to the teaching method -SIGHT: bananas at different ripening states -SMELL: onion and garlic, what does their smell hint of their other properties? -HEARING: peeling of potatoes, grating of carrots, biting a crispbread, peeling a banana (identification blind-folded) -TASTE: dried fruits differing in flavor and color, choosing the favorites and discussion whether the flavor was as expected -TOUCH: mouthfeel of carrot and crispbread, comparison of how they feel in hands -learning of basic tastes -addition of sugar to a sour black currant juice: what happens? -foods with different salt content: you taste the difference? -connecting food with taste (pictures of different foods and taste names) -learning and description of smell of different aromas (cardamom, carrot, vinegar, pineapple, lemon) -demonstration of retronasal odor (sip of vanilla aroma solution nose pinched and unpinched) -comparison of the smells of orange peels, juice and marmalade (intensity, pleasantness) -drawing task: fruits that smell good -homework: which spices are used at home and how is their smell Sense of taste Sense of smell Traditional Finnish foods Geography of foods (ethnic foods) Recapitulation Visit to a restaurant -discussing of foods that go well together -balancing flavor: tasting plain lemon and discussing the flavor and after that, adding sugar on the lemon and tasting again -off-flavors: fruit salad that has been contaminated with onion flavor -discussion of different off-flavors and their reasons -pictures of foods with different color, shape, size -pictures of gourmet dinner, fast food, everyday food: how they differ? -juices with inappropriate colors (for example red orange juice): discussion -coca cola and diet pepsi: similar appearance, different flavor -green and red salsa, why they look different? -homework: description of school lunch -samples with different texture in opaque bags, description and identification based on touching them with hands -fruits and vegetables (apple, pineapple, potato), touching and describing the texture, cutting them with knives and evaluating the hardness -temperature, cold and hot water in a bottle: comparison -dairy products (yogurt, sour milk and ‘‘viili”) in transparent bottles, observing the movements -mouthfeel of fat: tasting table spread -trigeminal sensations, hot and cold (chili and peppermint):discussion -tasting traditional Finnish food products like sal ammoniac (‘‘salmiakki”), Finnish Easter pudding (‘‘mämmi”) and oven-baked cheese (‘‘leipäjuusto”) -where milk and meat come from? -seasonal foods in Finland: discussing food traditions from January to December -pictures of ethnic foods, discussion -sensory description of ethnic fruits: lychee, avocado, pitahaya, rambutan, cape gooseberry -description of appearance, smell and touch feel of herbs -learning and description of the smell of ethnic spices -red and green chili sauce -recapitulation of contents of the earlier lessons -practical exercises on using one’s senses in eating -introduction to restaurant environment and food: preparing of the food, menus, set out of food, ordering of food, setting for dinner S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 239 Appendix B Appendix The second wave of the sensory education program Topic Content of the lesson Cereal products (porridge) (Raisio Ltd) -tasting and description of porridges made from oat, barley, wheat or rye -effect of temperature on sensory properties of porridge: demonstration -preparation and tasting of cereal-based snacks: fruit smoothie and fresh strawberry porridge Yogurt and aromas (Valio Ltd and Biofincon Ltd) -adding strawberry jam to yogurt: what happens to sweetness, sourness, thickness and flavor intensity? -tasting salty yogurt and then dipping bread to it: which option you like more? -acting as a product developer: flavoring of yogurts with different jams (apricot, licorice, banana, tutti-frutti, chocolate, toffee, citrus); letting others to taste and comment Cereal products (rye bread) (Fazer Bakeries Ltd) -visit to a large Finnish bakery -tasting of rye bread snacks -creation of descriptive words or slogans related to rye -making sandwiches of rye bread - getting acquainted with large-scale bread manufacturing (from dough to packages) Cheese (Valio Ltd) -introduction to cheese manufacturing -description of four cheese types: Emmenthal, Edam, Brie, blue cheese using cheese flavor wheel -how fat content affects to sensory properties of cheese (edam) -feta cheese made from cow’s or goat’s milk: how does the milk quality affect their sensory properties? Meat products (meat pilot plant of the Department of Food Technology) -getting acquainted with manufacturing of frankfurter in a pilot plant -sensory description of two different types of meat products, salami and frankfurter References Birch, L L (1979) Preschool children’s food preferences and consumption patterns Journal of Nutrition Education, 11, 189–192 Birch, L L (1999) Development of food preferences Annual Reviews of Nutrition, 19, 41–62 Birch, L L., Gunder, L., Grimm-Thomas, K., & Laing, D G (1998) Infants’ consumption of a new food enhances acceptance of similar foods Appetite, 30, 283–295 Cain, W S., de Wijk, R A., Lulejian, C., Schiet, F., & See, L.-C (1998) Odor identification: Perceptual and semantic dimensions Chemical Senses, 23, 309–326 Carruth, B R., Skinner, J., Houck, K., Moran, J., Coletta, F., & Ott, D (1998) The phenomenon of ‘‘Picky Eater”: A behavioral marker in eating patterns of toddlers Journal of the American College of Nutrition, 17, 180–186 De Wijk, R A., & Cain, W S (1994) Odor quality: Discrimination versus free and cued identification Perception and Psychophysics, 56, 12–18 Drewnowski, A (2000) Sensory control of energy density at different life stages Proceedings of the Nutrition Society, 59, 239–244 Gillman, M W., Rifas-Shiman, S L., Frazier, A L., Rockett, H R H., Camargo, C A., Jr., Field, A E., et al (2000) Family dinner and diet quality among older children and adolescents Archives of Family Medicine, 9, 235–240 Guinard, J.-X (2001) Sensory and consumer testing with children Trends in Food Science and Technology, 11, 273–283 Haapalahti, M., Mykkänen, H., Tikkanen, S., & Kokkonen, J (2003) Meal patterns and food use in 10- to 11-year-old Finnish children Public Health Nutrition, 6, 365–370 Hagman, U., & Algotson, S (2000) Mat för alla sinnen-sensorisk träning enligt SAPEREmetoden Stockholm: Blomberg & Jansson Huotilainen, A (2005) Teachers’ evaluation of sensory education Unpublished report, April 7, 2005 (in Finnish) Jahns, L., Siega-Riz, A M., & Popkin, B M (2001) The increasing prevalence of snacking among US children from 1977 to 1996 Journal of Pediatrics, 138, 493–498 Jonsson, I M., Ekström, M P., & Gustafsson, I.-B (2005) Appetizing learning in Swedish comprehensive schools: An attempt to employ food in a new form of experimental education International Journal of Consumer Studies, 29, 78–85 Lehrner, J P., Glück, J., & Laska, M (1999) Odor identification, consistency of label use, olfactory threshold and their relationships to odor memory over the human lifespan Chemical Senses, 24, 337–346 Loewen, R., & Pliner, P (1999) Effect of prior exposure to palatable and unpalatable novel foods on children’s willingness to taste other novel foods Appetite, 32, 351–366 Lumeng, J C., Zuckerman, M D., Cardinal, T., & Kaciroti, N (2005) The association between flavor labeling and flavor recall ability in children Chemical Senses, 30, 565–574 Mennella, J A., Pepino, M Y., & Reed, D R (2005) Genetic and environmental determinants of bitter perception and sweet preferences Pediatrics, 115, e216–e222 Neumark-Sztainer, D., Hannan, P J., Story, M., Croll, J., & Perry, C (2003) Family meal patterns: Association with sociodemographic characteristics and improved dietary intake among adolescents Journal of the American Dietetic Association, 103, 317–322 Nicklaus, S., Boggio, V., Chabanet, C., & Issanchou, S (2004) A prospective study of food preferences in childhood Food Quality and Preference, 15, 805–818 Oerlemans, P., Mustonen, S., Esselström, H., & Tuorila, H (2006) Sensory and food related perceptions of 8-, 9-, 10- and 11-year-old school children: Baseline measurements Research report in EKT series 1362 Helsinki: Department of Food Technology, University of Helsinki, University Press Pliner, P (1994) Development of measures of food neophobia in children Appetite, 23, 147–163 Pliner, P., Pelchat, M., & Grabski, M (1993) Reduction of food neophobia in humans by exposure to novel foods Appetite, 20, 111–123 Pliner, P., & Salvy, S-J (2006) Food neophobia in humans In R Shepherd & M Raats (Eds.), Psychology of food choice (pp 75–92) Wallingford: CABI Publishing Popper, R., & Kroll, J J (2005) Conducting sensory research with children Journal of Sensory Studies, 20, 75–87 Puisais, J., & Pierre, C (1987) Le goût de l’enfant Paris: Flammarion Reverdy, C., Chesnel, H., Schlich, P., Köster, E P., & Lange, C (2008) Effect of sensory education on willingness to taste novel food in children Appetite, 51, 156–165 Roedder, D J (1999) Consumer socialization of children: A retrospective look at twenty-five years of research Journal of Consumer Research, 26, 183–213 Salo, A (2007) Children as food experts – Perceptions of sensory education M.Sc thesis in food economics series 204 Department of Economics and Management University of Helsinki, Helsinki: University Press (in Finnish) 240 S Mustonen et al / Food Quality and Preference 20 (2009) 230–240 Spinath, B., & Spinath, F M (2005) Longitudinal analysis of the link between learning motivation and competence beliefs among elementary school children Learning and Instruction, 15, 87–102 Sune, F., Lacroix, P., & de Kermanec, F H (2002) A comparison of sensory attribute use by children and experts to evaluate chocolate Food Quality and Preference, 13, 545–553 Ton Nu, C (1995) Effects of a teaching programme about taste and gastronomy on school children’s eating behavior and food neophobia Food for the consumer AIR-CAT meeting reports vol 1: Progress during 1995 (p 74), AIR-CAT Project, c/o MATFORSK, Ås, Norway Veugelers, P J., & Fitzgerald, A L (2005) Prevalence and risk factors for childhood overweight and obesity Canadian Medical Association Journal, 173, 607–613 ... the flavor and after that, adding sugar on the lemon and tasting again -off-flavors: fruit salad that has been contaminated with onion flavor -discussion of different off-flavors and their reasons... description of smell of different aromas (cardamom, carrot, vinegar, pineapple, lemon) -demonstration of retronasal odor (sip of vanilla aroma solution nose pinched and unpinched) -comparison of the... Fazer Bakeries) and a sweet loaf (Setsuuri, Fazer Bakeries); in the second follow-up dark loaf (Maalahden limppu, Malax Limpan Ltd.) and grainy wheat toast (Jyväinen IsoPaahto, Vaasan and Vaasan

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