CONSUMER WILLINGNESS TO PAY FOR VITAMIN A FORTIFICATION IN VEGETABLE OIL IN SOUTH WESTERN NIGERIA: A CONTINGENT VALUATION APPROACH

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1 CONSUMER WLLNGNESS TO PAY FOR VTAMN A FORTFCATON N VEGETABLE OL N SOUTH WESTERN NGERA: A CONTNGENT VALUATON APPROACH ABSTRACT On, O. A. Department of Agrcultural Economcs, Unversty of badan, badan, Ngera The fortfcaton of Vegetable ol, among other food products wth Vtamn A s n a bd to reduce the Vtamn A defcency status of Ngeran ctzens. The study was carred out to determne the wllngness to pay of consumers for the fortfcaton of vegetable ol wth Vtamn A. Ths was carred out by frst determnng the awareness of consumers of the fortfcaton of vegetable ol wth Vtamn A, and then estmatng ther wllngness to pay usng a contngent valuaton method. The contngent valuaton method s used to estmate the value placed on non market goods. t works by creatng a hypothetcal market scenaro for a certan good or servce and then placng a value on ts perceved benefts. The study was carred out n two states n Southwest Ngera- Lagos and Oyo States. Two local governments were purposvely selected from the two states wth respondents were randomly selected based on proportonate to sze prncple. From the study, t s seen that total food, non food and vegetable ol expendture were N , N and monthly respectvely. The result reveals that over 60% of the respondents were aware of Vtamn A fortfcaton n vegetable ol, wth 76% wllng to pay the premum of N to obtan the fortfed vegetable ol. The probt estmaton of the contngent valuaton shows that prce of vegetable ol, log of household expendture, log of vegetable ol expendture, age of household head and locaton sgnfcantly mpacted on the probablty of beng wllng to pay for vtamn A fortfcaton n vegetable ol. Thus, t s concluded that there s a reasonable level of awareness and wllngness to pay for vtamn A fortfcaton n vegetable ol n southern Ngera. Arsng from the foregong, t s recommended that polces that wll enhance respondents purchasng power should be pursued n order to encourage them to pay for Vtamn A fortfed vegetable ol.. Keywords: Fortfcaton, Vtamn A, Wllngness to pay, Contngent valuaton NTRODUCTON Access to balanced det s sad to be a prerequste for good growth. n fact, food securty s not complete wthout the dmenson of Food Utlzaton whch nvolves the use and nutrtonal benefts to be derved from the food consumed. Certan mcronutrents present n food however may not be adequately consumed to meet the requred needs of the body, and thus there may be a need for fortfcaton of certan food products wth such mcronutrents. Most of these nutrents have far reachng defcency consequences. One of such nutrents whch need to be adequately present n consumed food s Vtamn A..Vtamn A, also called Retnol s a Fat soluble vtamn. ts sources nclude palm ol, carrots, lver, poultry meat, egg yolk and mlk. Other plant sources nclude many of the dark leafy vegetables, oranges, squash, and mango, (De Pee et al, 1998). Beng a fat soluble vtamn, therefore gves the benefts that ts fortfcaton can be ntated n vegetable ol, whch s one of the maor cookng ols used n Ngera. Vtamn A s a very mportant mcronutrent needed for good growth, good vson and other physologcal growths. Defcency of vtamn A n dets leads to reducton n the mmune system, poor epthelal growth, bad vson, and even some form of nfertlty. Thus, there s a need to get adequate amount of ths nutrent n the dets of Ngerans to ensure proper growth. Ths can be carred out through fortfcaton Mcronutrent defcences are serous health and publc health ssues, (Kkafunda, 2007). One of such mcronutrents s Vtamn A, whose defcency s a publc health ssue that affects both chldren and adults. Vtamn A defcency s a maor cause of chldhood blndness worldwde. Defcency of vtamn A has also been known to cause reducton n the mmune defense of the body leadng to morbdty and death, especally n chldren. Murphy (1995) report that an estmated 250,000 to 500, 000 chldren become blnd and close to half of them de n the year and become blnd. West, (2002), n a Meta analyss survey shows that about 127 mllon chldren experence vtamn A defcency n one form or another n developng countres. Accordng to the Natonal Food Agency for Food and Drug Admnstraton and Control, NAFDAC n Ngera, there s a hgh level of mcronutrent malnutrton n Ngera, especally among women and chldren. Ths gave rse to the need for food fortfcaton wth Vtamn A and other essental nutrents. There s however a need to examne the response of people to ths need for fortfcaton and thus the effectveness of any ongong vtamn A fortfcaton process n Ngera, through consumers awareness and ther wllngness to purchase the fortfed food product. Ths s one area where ths study s out to add knowledge. NJAFE VOL. 8 No. 2,

2 Fortfcaton s the addton of one or more nutrents nto food n order to meet certan nutrtonal needs of man. The am of ths fortfcaton s to prevent certan defcences that may arse from the non use or nadequacy of these nutrents, (Mashd et al., 1999). Accordng to L abbe et al., 2003, food fortfcaton s a publc health ntatve used to remedy nutrtonal defcences worldwde. Changng lfestyle and the consumpton of more processed food has led to the need for fortfcaton n order to ensure adequate nutrtonal requrements, (Hoffpauer and Wrght, 1994). Food fortfcaton can ether be Mass fortfcaton or Unversal Fortfcaton. n mass fortfcaton, the ntatve s brought about, mandated and regulated by the government of a country n order to meet mcronutrent needs of the ctzens from the consumpton of common foods such as cereals, and spces. Unversal fortfcaton nvolves the fortfcaton of food products for both anmals and man s needs. Vegetable ol s the man cookng ol n many countres. n Uganda, ts use s about 91% wthn the populaton, (Kkafunda, 2007). Ngera also uses a great deal of vegetable ol, and thus the study of vegetable ol and ts nutrtonal values has far reachng coverage n any food development proect. Vegetable ol s also an mportant drver of fortfcaton wth the mcronutrents of concern, snce vtamn A s a fat soluble vtamn. However, there s a need to examne and establsh local consumpton patterns, the awareness of fortfcaton, ts acceptance, affordablty and overall wllngness of consumers to purchase vtamn A fortfed vegetable ols as aganst the non fortfed ols. Awareness s expected to lead to the wllngness of the consumers to demand for the fortfed vegetable ol. Thus, the need to determne frst, the level of awareness of the mportance of vtamn A fortfcaton n vegetable ol and the premum that consumers are wllng to pay to access ths fortfed product s a maor challenge n the publc health concern of nutrton. Ths s another area of value addton to knowledge of ths study. Ngera s one of the frst countres n the sub Sahara Afrca regon to mandate fortfcaton of three food producemaze and wheat flour, vegetable ols and salt. Thus, there s a polcy on ground as regards the preventon of defcences arsng from the nadequate consumpton of crtcal mcronutrents. The need therefore arses for the sustanablty of such polces and program n order to fully combat the problem of mcronutrent malnutrton, especally as regards Vtamn A, whch affects the most vulnerable n the socety-women and chldren. The determnaton of the level of awareness and hence wllngness to pay of consumers for vtamn A fortfed vegetable ols s mportant n provdng the relevant agences nvolved n food regulaton and admnstraton the relevant data/nformaton needed to determne, develop and sustan effcent food fortfcaton programs. There have been dfferent analytcal technques used n the evaluaton of wllngness to pay, ncludng the transportaton cost, hedonc prcng, contngent valuaton and the choce experment. However, ths study wll make use of the contngent valuaton approach. Whle ths approach started wth the valuaton of envronmental goods/servces as well as publc goods, ts use n food valuaton have been on the ncrease. The advantage of ths method s that t s not necessary to develop attrbutes for determnng the wllngness to pay. Also, the use of ths method wll enable the study determne the prce value placed on fortfcaton of vegetable ol wth vtamn A and hence help both marketers and polcy makers n havng drect prce values. Ths wll allow for determnaton of the consumers characterstcs that nfluence wllngness to pay for a hypothetcal good (Contngent valuaton). The overall obectve of ths study s to determne the wllngness to pay for vtamn A fortfcaton n vegetable ol. Frstly, we descrbe the level of awareness of respondents on vtamn A fortfcaton n the study area and dentfy the factors that determne wllngness to pay for the fortfed vegetable ol n the study areas. Then, we estmate the mean wllngness to pay for vtamn A fortfcaton n vegetable ol n the study areas. Lterature revew Functonal foods nclude whole food tems, food that are fortfed, enrched or enhanced for ther potental benefts on ther health. The maor stakeholders n functonal food development nclude the consumers, local and natonal health sectors, the government and the food ndustry as a whole, (McConnon and Pearman, 2002). The consumers are nterested n functonal foods for ther health benefts, the government and food regulatory sector for the health of the ctzens and the food ndustry as a result of the hgher values that accrue to the food whch translates nto hgher margn. The development and sustanablty of functonal food s n a great way determned by the awareness the end users have about the health benefts of the food tems. Chlds and Poryzees (1997), reports that socoeconomc characterstcs such as gender, ncome and educaton are sgnfcant n determnng awareness of foods wth health benefts. Others nclude personal trats, processng methods, prce of the products and consumer percepton, (Bech-Larsen and Grunert, 2003) However, functonal foods may not be acceptable as expected as a result of certan factors such as hgh prces and skeptcsm about the health clams. Food fortfcaton s therefore a more pragmatc means of makng sure that people access essental nutrents. Food fortfcaton s mportant n treatng/preventng nutrtonal defcences as well as promote general well beng, usually targeted to specfc populaton. Food fortfcaton could also be used to restore nutrent lost durng processng, such as nutrent lost durng gran mllng, (Park et al, 2000).However, the effectveness of a food fortfcaton programme s dependent on ts acceptance, purchase and consumpton by the target populaton, the mprovement n the health status of the populaton. There s also a need to ncorporate food fortfcaton NJAFE VOL. 8 No. 2,

3 programmes as a part of a comprehensve strategy to reduce mcronutrent mbalance, n order to ensure the success and sustanablty of the programme, (FAO, 2003) Wllngness to pay for foods s nara value a consumer places on the perceved health benefts of the food tem, and thus t could be used to measure the benefts of the products to consumers, (Golan and Kuckler, 1999). The wllngness to pay functon dentfes the prce a consumer s wllng to pay for a gven quantty of food gven specfc levels of prce and utlty. Snce such deologcal benefts as food safety and nutrton are hard to measure, the use of wllngness to pay s mportant n placng the perceved value that consumers place on the deologcal benefts. t s also mportant n the food ndustry n placng the rght premum on product nnovaton, (Unnevehr et al, 1999). Wllngness to pay for foods s affected by factors that nclude socoeconomc characterstcs of the consumers, product attrbutes and government regulaton. Socoeconomc factors such as age, gender, ncome, educaton and household szes determne consumer wllngness to pay, (Govndasamy and tala, 1999, Kkafunda, 2007). Product qualty and other attrbutes also determne the levels of wllngness to pay for functonal foods, (Van Ravensway and Wohl, 1995, Lancaster, 1966). The study ntends to use both the Contngent Valuaton method n examnng the wllngness to pay of consumers for vtamn A fortfcaton n the vegetable ols they consume. Wllngness to pay s the nara amount a consumer s wllng to gve up or pay n order to acqure a good or servce. t could also be descrbed as the sum that represents the dfference between a consumer surplus before and after makng an mprovement n the sad attrbute of the food product. One of the man ways n determnng consumer wllngness to pay s the contngent valuaton method. ntally used n valung envronmental and publc goods, t has been extended to beng used for food products as well as prvate goods. Thus, the contngent valuaton method s generally used to estmate the values that ndvduals place on goods not sold n the markets, such as good health, food safety, and envronmental ntegrty. The contngent valuaton method works by creatng a hypothetcal market scenaro for a certan good or servce, (Maynard and Frankln, 2003). t quantfes the value the consumers place on a certan food attrbute mprovement. The method asks the respondent to provde the prce or the percentage above current prce he/she s wllng to pay for a product. Ths assumes that there are premum prces, whch are got by carryng out a plot study.n carryng out a contngent valuaton; the survey seeks to use specfc desgns to determne consumer wllngness to pay for the goods and servces. The survey could ether be open ended or close ended n ts questons. The contngent valuaton method s very useful n the analyss of wllngness of consumers to pay for certan food or non food products. The method s qute smple to understand and carry out. The method also requres only the comparson between dfferent optons rather than drectly valung them. The contngent valuaton method s also the only method that s able to reveal the benefts of knowng that a good exsts even f t has not been experenced. However, the contngent valuaton method s lmted n the type of nformaton to be collected from the consumers, thus there mght be no actual representatve sample. Survey desgn for contngent valuaton s senstve and must be carefully framed to collect the type of nformaton requred. Theoretcal framework The ssue of choce and hence wllngness to pay are based on the theory of Random Utlty. Utlty n tself s the perceved beneft an ndvdual has to certan goods/servces. A subectve phenomenon, t can however be measured by how much the consumer s wllng to pay n order to acheve the utlty he desres. Ths theory, poneered by McFadden (1980), s based on the utlty maxmzaton theory of consumer preference. The consumer s assumed to be governed by ths utlty maxmzaton rule, n whch he chooses among a selecton of brand the one that gves hm the hghest utlty. However, whle there are some characterstcs that determne the choce a consumer makes, utlty n tself s not a totally determnstc varable, thus the term random utlty. Any devaton from the consumer actual and predcted choce s assumed to be due to the random error. Consder a consumer faced wth a choce between two baskets of goods, A and B, wth expected utlty of U A and U B. The theory of utlty assumes that a consumer s ratonal and thus wll choose a basket of good, B f the U B > U A. However, we cannot predct utlty exactly as result of certan characterstcs of the consumers and the product as well as the choce stuaton confrontng the consumer. Thus, we presume a random nature n utlty, whch assumes that utlty, U t, derved from a product by consumer s composed of a determnstc component, v and a random/stochastc component ԑ,.e. u 1 v Thus, the probablty of consumer, choosng from a set of choces s gven as : P Pr u u.2 P Pr v ' v ' ' ' '..3 The error terms are the unobserved random varables whch may be taken as a ont dstrbuton of all the error T terms,.e. They may be estmated by a cumulatve dstrbuton or a probablstc ( 1 2 3) NJAFE VOL. 8 No. 2,

4 dstrbuton. The usual model n ths estmaton s the multnomal logt model. However, n statstcs, most unobserved error terms are taken as normally dstrbuted, (Tran,2003), for whch t can be modeled as a Probt model, whch ths study wll employ. The f ( ) s assumed to be the ont dstrbuton of the error terms, havng mean, and a covarance matrx; makng t a probt model. The probt model takes the error term to be ndependently and dentcally dstrbuted, and thus the probablty of makng the choce of product can be shown as: P Pr v v 4 k k = k k k k k f v vk k f )( ( f ( ) d )) d..5 ( ( )( F ( v v )) d 6 = e k k METHODOLOGY Data The data used for ths study was a prmary data soured from two states n Southwest Ngera, Lagos State and Oyo State, from whch one local government each-kea and badan Northwest local government areas, respectvely were purposvely selected. kea local government area s one of the 20 local government areas n Lagos state. The captal of Lagos state, t s an uprsng area, wth an estmated populaton of about 313,000 (NPC, 2006). Wth a land area of 46km2, the local government area s made up of the followng communtes: Oregun, Oodu, Opeb, Akode, Alausa, Agdngb, kea, Ogba and Maryland. kea local government s home to a lot of ndustral acvtes, such as the Murtala Mohammed Arport, the Ngeran Cvl Avaton Authorty. The resdental areas n the local government are well planned and quet wth shoppng malls, supermarkets and other small and medum enterprses around. Resdents of kea are manly thought to be hgh ncome earners. badan Southwest Local government area, carved out of the badan Muncpal Government n 1991, has ts admnstratve headquarters n Oluyole Estate. Other areas wthn ths local government nclude Apata and Odo ona Usng the 2006 census estmates and smulatng a 3.2% growth, the 2010 populaton estmate of the local government s about 320, 000(three hundred and twenty thousand) people. Although, there are no serous agrcultural actvtes wthn the local government areas, t s home to a lot of agrcultural processng frms such as Caps feed, Zartech, Bronco, Avans and Aanla farms. Large and medum scale ndustres also abound wthn ths local government. nclusve of these s 7Up bottlng company, Procter and Gamble ltd, Yale Foods, Sumal food ltd and vtal foods ltd. The choce of the two local governments n the two states chosen s entrely purposve. t s assumed that nformaton and awareness of mcronutrent fortfcaton s hgher among the urban and educated populatons, whch may be found n such places as kea and the resdental areas of the badan Southwest Local government areas. At the second stage of the samplng selecton, however, random samplng was used. A smple random samplng usng proportonate to sze prncple by dfferent locatons mentoned n the Local government area was carred out to select 150 respondents from kea communty n the kea local government area. However, for badan North West local government area, the local government was stratfed nto two- Hgh ncome earners n Oluyole estate and mddle to low ncome earners n Apata and Odo ona resdental areas. A random samplng proportonate to sze was used to select a total of 150 respondents. Analytcal method The contngent valuaton method estmates the value that an ndvdual places on non market goods such as health, safety, envronmental ntegrty. Thus, f the person must purchase the good, the nara equvalent that the person wll pay whle stll keepng hs utlty s the measure of hs wllngness to pay for that good. Ths can be expressed as: WTP E( P, q 0, Q, U 0 1 ) E( P, q, Q, U 0 ) 1 Where, q 0, q 1 are the quanttes of the product wth q 1 >q 0. Q s the vector of other non market goods, U s the consumer s utlty when he consumes q 1 n estmatng the varatons n consumer wllngness to pay for a good, an econometrc functon can be expressed usng a cumulatve dstrbuton functon. t s to be noted that the wllngness to pay response comes as a dchotomous dstrbuton, and thus s ether estmated n a logstc (logstc regresson) or normal (probt NJAFE VOL. 8 No. 2,

5 regresson) dstrbuton. Estmatng wllngness to pay n a model estmates the bound of the WTP, and s expressed as WTP G( Z Y e ) Y X.2 Where G( Z Y e ) 0 0 G( Z Y e ) 1,.3 Y 1,..., n Thus, each th ndvdual s wllngness to pay s a functon of ncome(y), Z, whch s a vector of consumers socoeconomc characterstcs and e s the error term whch s assumed to contan a vector of unobservable household characterstcs. Assume that a prce of NA s placed on the fortfed vegetable ol; the probablty that an ndvdual wll be wllng to pay that sum of money s gven by: 1 Y A P(WTP/A) = 1 exp Z Y ln( ) /..4 A Emprcal Estmaton of the Probt Model The probt model that wll be used to estmate the probablty of purchasng the fortfed vegetable ol under alternatve scenaro s gven by: Y f ( X 1 U )..5 Where, Y s the consumer wllngness to pay for vtamn A fortfcaton (yes,=1 otherwse,=0) X s the vector of explanatory varables Α s the vector of parameters U s the error term For the study, the varables of nterest are as follows: X 1 =Bd prce (hypothetcal prce for whch the fortfed vegetable ol s sold) n Nara X 2 = Square of bd prce n Nara X 3 =Gender of household head (Male=1, Female=0) X 4 = Age of household head (Years) X 5 = Age squared (Years) X 6 =Years of formal educaton X 7 = household sze (Number) X 8 = Natural log of Household food expendture (Nara) X 9 = Natural log of Household Vegetable ol expendture (Nara) X 10 =Natural log of Household Non-food expendture (Nara) X 11 =Locaton (Lagos =1, Oyo =0) Socoeconomc characterstc of respondents Table 1 presents a summary of the socoeconomc characterstcs of the respondents n ths survey. These are the socoeconomc factors that are expected to a pror have some knd of effect on the wllngness to pay for vtamn A fortfcaton n vegetable ol. RESULTS AND DSCUSSON Table 1 show that the average, male respondents consttute about 47% representaton. On the average, the respondents age s estmated at 34 years old. The age range dstrbuton shows that over 76% of the respondents are less than or equal to forty years of age. The average household sze s found to be 5 members. Consumers n the study areas have on the average,15 years of formal educaton,.e some form of tertary educaton; the educatonal attanment dstrbutons shows that over 76% of the respondents have tertary educaton. The occupaton group dstrbuton shows that there are more cvl servants (gven at 34%) than other occupatonal groups. The mean expendture on food, non food and vegetable ol are gven as N , N and respectvely. Ths mples that the expendture on vegetable ol s almost 10% of total food expendture n Southwest Ngera, showng the mportance of vegetable ol n the det of Ngerans. The average prce that consumers are wllng to pay for fortfed vegetable ol s gven as N421.37, whch s almost 100% the prce of non-fortfed vegetable ol n the markets (N ). NJAFE VOL. 8 No. 2,

6 Table 1: Socoeconomc characterstc Varables Freq. Percent Mean Std. Dev. Sex (1=Male, 0=Female) Age (years) Years of formal educaton Household sze Food Expendture Non-food Expendture Vegetable ol Expendture Wllngness to pay for fortfcaton Awareness of Vt A fortfcaton Mean Prce State (1=Lagos, 0=badan) Occupatonal Group Professonals Cvl Servants Artsans Traders Others Age group <= > Educatonal Group Prmary Secondary Tertary Source: Computaton from feld survey About 64% of the respondents were aware of vtamn A fortfcaton n vegetable ol and 79% of these were wllng to pay a premum to purchase the fortfed vegetable ol. n all, these socoeconomc characterstcs are evenly dstrbuted between the two states. Probt model analyss of wllngness to pay for vtamn A fortfcaton n Vegetable ol. Table 2 shows the result of the normal dstrbuton analyss of wllngness to pay usng a probt regresson. The result reveals that the log lkelhood rato s sgnfcant at 1%; the pseudo R 2 ndcates that about 85% of the varatons n the dependent varable (WTP) s explaned by the ndependent varables. Thus, from the dagnostc tests, we show that the model fts the data properly. Seven of the varables have sgnfcant coeffcents at varous levels of sgnfcance. The prce (postve) and prce squared (negatve) are sgnfcant determnants of wllngness to pay for fortfcaton n ths study. Ths mples wllngness ncreases wth prce to a lmt after whch t declnes as prce goes hgher. The coeffcent of age of the consumer has the expected sgns and s sgnfcant. Ths mples that as the consumer grows older, the wllngness to pay for fortfed vegetable ol decreases. However, t s seen that the age square though not sgnfcant has a postve sgn, probably mplyng that there s a more conscentous effort by older people n consumng healther and safer food products. The natural log of household expendture and vegetable ol expendture whch serve as proxy for dsposable ncome and share of ncome meant for vegetable ol are sgnfcant and show the expected sgns. An ncrease n the consumer s ncome s expected to ncrease hs wllngness to pay snce he s now able to afford the premum placed on the fortfed vegetable ol. n the same ven, f the ncome for vegetable ol consumpton ncreases, there s a lkelhood that the consumer wll be wllng to pay for the vtamn A vegetable ol. A percentage ncrease n the log of household food expendture s expected to ncrease the wllngness to pay by 0.07 percent, whle an ncrease n log of vegetable ol expendture by1 percent wll ncrease the wllngness to pay of the consumer by 0.03 percent. The result also shows that beng a resdent of Lagos state rather than Oyo state ncreases the probablty of beng wllng to pay for vtamn A fortfed vegetable ol by 0.5 percent NJAFE VOL. 8 No. 2,

7 Table 2: Maxmum Lkelhood Estmaton of the Contngent Valuaton Varables Coeffcent Standard Error Elastctes Prce 0.082*** Prce squared *** 3.5E Gender(1=male, 0=female) Age(years) * Age squared Years of formal educaton Household sze Ln of household food 1.030** expendture Ln of household vegetable 0.698** ol expendture Ln of household non food expendture Locaton(1=Lagos, 1.595*** =badan) Constant *** Log Lkelhood *** Pseudo R-squared *,**,***: sgnfcance level at 10%, 5% and 1% respectvely CONCLUSON AND POLCY RECOMMENDATON The use of the contngent valuaton method was used n estmatng the wllngness to pay for the fortfcaton of vtamn A n vegetable ol n Ngera. t was found that a hgh percentage of consumers are aware and wllng to pay for the fortfcaton of the vtamn A they consume. The bd prce of N represents the prce that the consumers are wllng to pay to stays healthy n terms of ths mcronutrent. Arsng from the foregong, t s recommended that polces that wll enhance respondents purchasng power should be pursued n order to encourage ther wllngness to pay for Vtamn A fortfed vegetable ol.. REFERENCES Bech, Larsen T. and Grunert K. G, 2003, The Perceved Healthness of Functonal Foods: Co ont Study of Dansh, Fnnsh and Amercan Consumers Percepton of Functonal Foods. Pubmed publcaton, Appette, 40(1):9-14 Bech-Larsen, T., 2000, Model based Development and Testng of Advertsng Messages: A Comparatve Study of Tow Campagn Proposals Based on the MECCAS Model and a Conventonal Approach. nternatonal Journal of Advertsng: the Quarterly Revew of Marketng Communcaton, 20 (1) Chlds, N. M and Poryzees G. H, 1997: Foods that Help Prevent Dsease: Consumer Atttudes and Publc Polcy mplcatons. Journal of Consumer Marketng, 14(6): De Pee S, Bloem M, Gorsten J, Sar M, Satoto, Yp R, Shrmpton R Muhlal, Reapprasal of the Role of Vegetable n Vtamn A Status of Mothers n Central Java, ndonesa. PubMed, AM J Cln Nutr, 68(1): Food and Agrcultural Organzaton, FAO, Fortfcaton of Food wth Mcronutrents.Food and Nutrton Dvson Polcy Statement. nternet resource, retreved ftp://ftp.fao.org.docrep/fao/005/y8346m/o.pdf. Golan, E. and Kuckler F., Wllngness to pay for Food Safety: Costs and Benefts of Accurate Measures. Amercan Journal of Agrcultural Economcs, 81(5): Govndasamy, R. and tala J., Predctng Wllngness to pay a Premum for Organcally Grown Fresh Produce. Journal of Food Dstrbuton Research, 30(1):44-53 Hoffpauer, D. W. and Wrght S. L Enrchment of Rce. Ed W.E Marshall and J. Wadsworth: Rce Scence and Technology, New York. Kkafunda J. K., Assessng the Sutablty for Vegetable Cookng Ol as a Food Vehcle for Vtamn A Fortfcaton n Uganda. Afrcan Crop Scence Socety, 8(1);, L abbe, M. R. Cockell, K. A and Nora S. L, Mcronutrent Supplementaton: when s best and Why? Proceedngs of the Nutrton Socety, 62( 2): Lancaster K, J A New Approach to Consumer Theory. Journal of Poltcal Economy, 74 (2): NJAFE VOL. 8 No. 2,

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