Abstract
Food fortification is an important strategy for addressing micronutrient malnutrition, especially relating to, among others, vitamin A deficiency (VAD) in developing countries. Current efforts to tackle VAD in developing countries include biofortification and industrial fortification. In Kenya, the recent formulation of the national food security and nutritional policy has spurred efforts to fortify sugar with vitamin A to complement the on-going biofortification efforts targeting rural farm households. This study assessed consumer preferences for sugar that is industrially fortified with Vitamin A. The study used data collected from a random sample of 350 sugar consumers drawn from rural and peri-urban areas of Kenya. Preference data were collected using choice experiment method and analysed using the random parameter logit regression technique. Results show that consumers had positive and heterogeneous preferences for the key attributes of fortified sugar including natural fortificants, inclusion of gift packs and fortification labels, minimum levels of vitamin A and the colour of the grains. Consistent with the current campaigns, respondents from households with infants and lactating mothers had higher preferences for fortified sugar than those with aged members or the youth. The paper discusses the implications of these findings for production and marketing policy.
L’enrichissement des aliments est une stratégie importante pour traiter les carences en micronutriments. En conséquence, les gouvernements des pays en voie de développement investissent dans la fortification des aliments les plus consommés. Toutefois, il existe peu d’évidence concernant la préférence des consommateurs pour les produits enrichis dans ces pays. Cette étude fait l’usage de la méthode d’expérimentation des choix et d’un échantillon aléatoire de 350 consommateurs de sucre, venant du Kenya rural et urbain, pour évaluer les préférences des consommateurs pour le sucre enrichi en vitamine A, sous différents scénarios d’enrichissement. Les données ont été analysées en utilisant un modèle logit-logistique à paramètres aléatoires. Les résultats indiquent que les consommateurs ont des préférences positives et hétérogènes pour les attributs clés du sucre fortifié. Conformant avec les campagnes de nutrition actuelles, les répondants provenant des ménages avec des enfants, et les mères allaitantes, ont plus de préférences pour le sucre fortifié que les ménages comprenant des personnes âgées ou des jeunes. L’étude conclut que les consommateurs de sucre sont prêts à payer des primes élevées pour le sucre enrichi en vitamine A, et examine les implications de ces conclusions pour les politiques.
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Kennedy Otieno Pambo and David Jakinda Otieno have contributed equally to this work.
Appendices
Appendix
Appendix 1.1: NGENE Choice Experiment Design Syntax
(a) Orthogonal design for preliminary survey
Design
;alts = alt1, alt2
;rows = 36
;block = 6
;orth = sim
;model:
U(alt1) = b0 + b1*x1[0,1] + b2*x2[0,1,2] + b3*x3[0,1] + b4*x4[0,1] + b5*x5[0,1,2] + b6*x6[0,1,2]/
U(alt2) = b1*x1 + b2*x2 + b3*x3 + b4*x4 + b5*x5 + b6*x6$
(b) Efficient design for final survey
Attributes are listed in this order:
X1 = Type or source of Vitamin A
X2 = Level of vitamin A
X3 = whether labelled or not
X4 = Gift or no gift
X5 = Colour
X6 = Price
(a) Syntax
Design
;alts = alt1, alt2
;rows = 24
;block = 6
;eff = (mnl,d)
;model:
U(alt1) = b1[0.978]*x1[0,1] + b2[0.505]*x2[0,1,2] + b3[0.901]*x3[0,1] + b4[0.753]*x4[0,1] + b5[0.356]*x5[0,1,2] + b6[−0.004]*x6[0,1,2]/
U(alt2) = b*x1 + b2*x2 + b3*x3 + b4*x4 + b5*x5 + b6*x6$
(b) Efficiency measures
D-error = 0.1399 [D-efficiency or D-optimality measure is 0.861 or 86 per cent]
A-error = 0.230 [A-efficiency measure is 77 per cent]
B-estimate = 84.85 per cent
S-estimate = 17148.75
Appendix 1.2: List of All Choice Sets Used in the CE Survey
Profile One
Scenario 1
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 5 | 15 | |
Labelling | Yes | No | |
Gift pack | Yes | N | |
Colour | Yellowish | White | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 2
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 15 | 5 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | Brown | Brown | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 3
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 10 | 10 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | Brown | Brown | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 4
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 5 | 15 | |
Labelling | No | Yes | |
Gift pack | No | Yes | |
Colour | White | Yellowish | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Profile Two
Scenario 1
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 15 | 10 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | Brown | Brown | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Scenario 2
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 10 | 10 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | Brown | Brown | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 3
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 5 | 15 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | Yellowish | White | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Scenario 4
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 5 | 15 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | White | Yellowish | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Profile Three
Scenario 1
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 15 | 5 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | Yellowish | White | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 2
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 10 | 10 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | White | Yellowish | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Scenario 3
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 15 | 5 | |
Labelling | No | Yes | |
Gift pack | No | Yes | |
Colour | White | Yellowish | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Scenario 4
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 10 | 5 | |
Labelling | Yes | No | |
Gift pack | Yes | No | |
Colour | Yellowish | White | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Profile Four
Scenario 1
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 10 | 10 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | White | Yellowish | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Scenario 2
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 5 | 15 | |
Labelling | No | Yes | |
Gift pack | No | Yes | |
Colour | Yellowish | White | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Scenario 3
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 15 | 5 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | Brown | Brown | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Scenario 4
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 15 | 5 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | White | Yellowish | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Profile Five
Scenario 1
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 10 | 10 | |
Labelling | Yes | No | |
Gift pack | No | Yes | |
Colour | Brown | Brown | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Scenario 2
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 15 | 5 | |
Labelling | Yes | No | |
Gift pack | Yes | No | |
Colour | Yellowish | White | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Scenario 3
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 5 | 15 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | Yellowish | White | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 4
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 15 | 5 | |
Labelling | Yes | No | |
Gift pack | Yes | No | |
Colour | Brown | Brown | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Profile Six
Scenario 1
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 10 | 10 | |
Labelling | No | Yes | |
Gift pack | Yes | No | |
Colour | White | Yellowish | |
Price | 120 | 180 | |
Which ONE would you prefer? |
Scenario 2
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 10 | 10 | |
Labelling | Yes | No | |
Gift pack | Yes | No | |
Colour | White | Yellowish | |
Price | 150 | 150 | |
Which ONE would you prefer? |
Scenario 3
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Natural | Artificial | |
Level of vitamin A | 5 | 15 | |
Labelling | No | Yes | |
Gift pack | No | Yes | |
Colour | Yellowish | White | |
Price | 180 | 120 | |
Which ONE would you prefer? |
Scenario 4
Sugar type A | Sugar type B | Neither | |
|---|---|---|---|
Source of vitamin A | Artificial | Natural | |
Level of vitamin A | 5 | 15 | |
Labelling | No | Yes | |
Gift pack | No | Yes | |
Colour | Brown | Brown | |
Price | 15 | 150 | |
Which ONE would you prefer? |
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Pambo, K.O., Otieno, D.J. & Okello, J.J. Analysis of Consumer Preference for Vitamin A-Fortified Sugar in Kenya. Eur J Dev Res 29, 745–768 (2017). https://doi.org/10.1057/s41287-016-0059-y
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DOI: https://doi.org/10.1057/s41287-016-0059-y