Comparing consumer preferences for color and nutritional quality in maize: Application of a semi-double-bound logistic model on urban consumers in Kenya

Consumer preferences for white maize in East and Southern Africa concerns developers of maize biofortified with provitamin A carotenoids, since carotenoids impart a yellow or orange coloration. Urban consumers’ willingness to pay (WTP) for yellow maize was estimated, using a semi-double-bounded logistic model, based on a survey of 600 maize consumers in Nairobi, Kenya, at posho mills, kiosks and supermarkets. Consumers showed a strong preference for white maize. Only a minority would buy yellow maize at the same price as white maize, and fewer consumers in the posho mills (24%) and kiosks (19%) than in the supermarkets (34%) would do so. On average, consumers need a price discount of 37% to accept yellow maize. This discount was less at the posho mills (35%) and kiosks (37%) than in the supermarkets (48%). Most respondents (76%) were aware of the existence of fortified meal and the generally showed an interest. The average premium for fortified maize was much less than the discount for yellow: 5.9% for those aware and 7.4% for those unaware. Consumer preferences were influenced by socioeconomic factors such as gender, education, income and ethnic background. Women have a stronger preference for both white maize and fortified maize than men, and consumers with more education have a stronger preference for white. Income decreases the WTP for yellow maize as well as the price elasticity, but increases the WTP for fortified maize. Consumers originating from Western Kenya have a lower preference for white, while those from Central Kenya had a stronger preference for fortified maize.     

Information,branding, certification,and consumer willingness to pay for high-iron pearl millet: Evidence from experimental auctions in Maharashtra,India

In this paper we use hedonic testing methods adopted from food science literature and the Becker-DeGroot-Marschak mechanism adopted from economic valuation literature to estimate consumer demand for biofortified high-iron pearl millet (HIPM) in Maharashtra, India. Unlike biofortification with provitamin A, biofortification with minerals, such as iron and zinc, does not change the color or the appearance of the biofortified crop. Therefore, we test the impact of both nutrition information, and branding and certification, as well as the nature of the brand and of the certifying authority (state level versus international), on consumer demand for HIPM. We find that even in the absence of nutrition information, consumers assign a small but significant premium to the HIPM variety relative to the local variety. This is consistent with consumers’ more favorable rating of the sensory characteristics of the high-iron variety. Nutrition information on the health benefits of HIPM increases this premium substantially, and regression analysis reveals that consumers prefer international branding and international certification authority to their state-level counterparts.     

Consumer acceptability of yellow maize products in Zimbabwe

This study analyzes consumers’ awareness of and attitudes towards yellow maize products in Zimbabwe and suggests intervention strategies that will ensure increased production and consumption of the crop, which is rich in provitamin A to help prevent the incidence of vitamin A deficiency prevalent among vulnerable groups. Data from 360 randomly selected rural and urban households show that yellow maize is known to all but few are aware of its nutritional qualities or consume it. The main source of supply is imported food aid. Rich in oils, carotenoids and fructose, yellow maize easily undergoes chemical changes to produce unacceptable organoleptic properties (or bad taste) if poorly handled during importation. These two factors are responsible for it being perceived inferior to white maize by consumers. Quality assurance during importation can improve consumer confidence but a long-term strategy will be to vigorously promote domestic production of yellow maize varieties rich in high levels of β-carotene that meet the preferences of consumers. Drawing from a probit model regression analysis, nutritional education can potentially promote yellow maize consumption, especially if targeted at low income households. Domestic production and consumption of yellow maize will decrease vitamin A deficiency among vulnerable groups and improve food insecurity through reduced grain prices and increased incomes for farmers. These results draw attention to the need for policy makers in developing countries to review their agricultural policies to ensure that they do not undermine the local production and consumption of nutritionally valuable crops.     

Consumer market segments for biofortified iron beans in Rwanda: Evidence from a hedonic testing study

An understanding of consumer market segments is important for efficient and effective targeting of new technologies, such as biofortified foods. In this paper, we use cluster analysis to identify distinct consumer segments in Rwanda for four biofortified iron bean varieties. Data on consumer liking of various sensory attributes of beans was collected by using a 7-point hedonic scale through the application of home-use and central location tests implemented in two rural and two urban locations. Cluster analysis reveals the existence of several distinct consumer segments in each one of the four study locations. Further analysis is conducted by using multinomial probit and logit models to predict consumer segment membership based on the consumer characteristics. Results reveal that, depending on the location, consumer’s source of income and whether or not they received information about nutritional benefits of the iron bean varieties have a bearing on their preference of these varieties. The paper presents a profile of each one of the consumer market segments identified to assist targeting of various iron bean delivery, marketing and promotion efforts in Rwanda.     

A meta-analysis of community-based studies on quality protein maize

Biofortification, or the improvement of nutritional quality in food crops, is a promising strategy to combat undernutrition, particularly among the rural poor in developing countries. However, traditional methods of impact assessment are inadequate for biofortified crops, as they do not consider their nutritional benefits. Evidence for the nutritional impact of maize varieties with improved protein quality, collectively known as quality protein maize (QPM), was evaluated using meta-analysis of randomized, controlled studies in target communities. A new and generalizable effect size was proposed to quantify the impact of QPM on a key outcome, child growth. The results indicated that consumption of QPM instead of conventional maize leads to a 12% (95% CI: 7–18%) increase in the rate of growth in weight and a 9% (95% CI: 6–15%) increase in the rate of growth in height in infants and young children with mild to moderate undernutrition from populations in which maize is the major staple food. The proposed effect size and use of bootstrapping to determine statistical significance addressed some methodological limitations in the existing studies.     

Could farmer interest in a diversity of seed attributes explain adoption plateaus for modern maize varieties in Malawi?

This study uses new data from a household survey (n = 179) in Mulanje District, Malawi to examine whether the observed adoption plateaus for modern maize varieties in Malawi partly reflect farmer interest in a diversity of maize seed attributes. Regression results for the study area indicate that specific attributes of different maize varieties are an important influence on their use. The benefits to growing hybrid maize appear to be yield and drought tolerance. Open pollinated varieties are selected by farmers who value early maturity. Local maize varieties are popular among farm households owing to a number of favourable processing and consumption characteristics: storability, poundability, flour-to-grain ratio, and taste. Further research using nationally representative data is needed to assess whether findings for Mulanje District can be generalized to Malawi as a whole. If future studies agree with the results herein then maize breeding research programs in Malawi should consider a diversity of traits beyond grain yield to encompass the range of production, processing, and consumption attributes that are valued by farmers.     

Information Unraveling Revisited: Disclosure of Horizontal Attributes

This paper analyzes in a spatial framework how much information a seller discloses about the variety he sells when he faces a buyer with a privately known taste for variety. I identify an equilibrium in which, for each possible variety, the seller's optimal strategy consists of either fully disclosing the variety or disclosing how far it is from the buyer's expected taste. The set of varieties the seller fully discloses monotonically expands as the buyer's taste for variety becomes stronger. I show that this is the unique undefeated equilibrium. From a policy perspective, mandating full disclosure is socially harmful.     

Recent developments in modifying crops and agronomic practice to improve human health

Malnutrition of micronutrients (vitamins and minerals) affects more than two billion people worldwide, especially in developing countries, largely due to low concentrations or poor bioavailability of these nutrients in the diet. In contrast, over-consumption, particularly of over-refined cereal-based foods, has contributed to the development of an “epidemic” of metabolic diseases in some developed countries. This review highlights recent progress in modifying crops and agronomic practice to increase health benefits. Mineral concentrations or bioavailability in crop edible parts can be increased by fertilisation, breeding or biotechnology. It is also possible to modify crops using transgenic technology to enable or increase the biosynthesis of vitamins and long chain omega-3 polyunsaturated fatty acids, or to modify the composition of starch or dietary fibre. Although technologically feasible now or in the near future, the development of micronutrient biofortified or composition-modified crops would also depend on other factors such as consumer acceptance, cost, regulations and national or international intervention.     

Is DNA fingerprinting the gold standard for estimation of adoption and impacts of improved lentil varieties?

In the early 1980s, disease susceptibility in short-season lentil landraces began to limit productivity in areas where relay cropping took place in Bangladesh. Since then, several improved high-yielding lentil varieties, which are resistant to rust and blight and suitable in the relay cropping system, have been released jointly by national and international research centers. This study used three methods, namely a panel of experts, a survey of 1000 households where the respondents named the variety they used, and DNA fingerprinting of seed samples collected from all lentil plots cultivated by survey households to estimate adoption. Double hurdle and instrumental variables regression methods were applied to the household survey and DNA fingerprinting data to identify determinants of adoption and measure their impacts. Of particular interest was whether estimates of adoption, determinants of adoption and impacts varied by method of variety identification. Results showed that the expert panel overestimated the adoption of more recent varieties while about 89% of the farmer-reported varieties were accurate, as verified by DNA fingerprinting. DNA fingerprinting appears to have little advantage for estimating the level of adoption in this case, where few varieties of lentils are found, local variety names do not exist, and most seed is obtained through a formal system. However, even under these conditions, determinants of adoption vary by identification method, and use of farmer-reported information on the variety can lead to erroneous conclusions about determinants of adoption. Because recent breeding efforts have focused on taste and cooking considerations, yield impacts were not significantly different from zero.     

Food self-sufficiency in Micronesia: Effects of a nutrition assistance programme on food consumption

Food assistance programmes in Micronesia have been blamed for creating disincentives to agriculture and nutritionally adverse dietary habits. In 1982 a USDA commodity programme in the Northern Mariana Islands was replaced by the Nutrition Assistance Program (NAP), which required that at least 25% of food coupons be used for the purchase of local foods. Consumption of local fish and bread increased, but consumption of local fruits and vegetables declined among NAP participants. Although targeted coupons did not reverse the trend towards imported foods, the bakery and fishery endeavours indicate that improved marketing can be coupled with food stamps to increase local food production and consumption.     

The effects of price deregulation on maize marketing margins in South Africa

There has been continuous controversy over the impact of food market reforms on food security in Africa. In South Africa, the government and media have often questioned the effects of price deregulation of maize meal, the major staple food, on consumers. This article determines the effect of retail price deregulation on the size of maize milling/retail margins in South Africa. Regression models of monthly milling/retail margins are run from the period May 1976 to December 2004. To assess the robustness of our findings, we estimate several different models of structural change, vary the sample period to examine the sensitivity of findings to unusual weather and market conditions in the region during episodes between 2001 and 2004, and run the models using different estimation techniques, OLS with Newey-West robust estimators and Feasible General Least Squares. In virtually all models, the results indicate that real maize milling/retailing margins in South Africa have increased by at least 20% since the deregulation of retail prices in 1991. Moreover, there is evidence of trend growth in the size of the milling margin over time. Simulations indicate that the deregulation of maize meal prices has entailed a transfer of at least US$179 million/year from consumers to agents in the marketing system. Further study is needed to understand why this outcome in South Africa differs from findings in other countries in the region concerning the effects of reform on food marketing margins.     

Food security implications of staple food substitution in Sahelian West Africa

Low-income households in Sahelian West Africa face multiple shocks that risk compressing their already-low food consumption levels. This paper develops a multi-market simulation model to evaluate the impact of common production and world-price shocks on food consumption of vulnerable groups in Sahelian West Africa. Empirical analysis confirms that poor households bear the brunt of ensuing consumption risks, particularly in closed markets, where trade barriers restrict imports, and the poor find themselves in a bidding war with richer consumers for limited food supplies. In the absence of trade, a drought that reduces domestic rainfed cereal production by 20% would compress already low calorie consumption of the rural poor by as much as 15%, four times as much as other household groups. Conversely, a 50% spike in world rice prices hits the urban poor hardest, compressing calorie consumption by up to 8%.Policy responses need to focus on two basic mechanisms that can help to moderate this pressure – consumer substitution among staple foods and trade. Immediately south of the Sahel, coastal West African countries enjoy higher rainfall, dual rainy seasons, more stable staple food production based on root crops (cassava and yams) as well as frequent double cropping of maize.Our simulation results suggest that regional trade in maize, yams and cassava-based prepared foods like gari and attieké could fill over one-third of the consumption shortfall resulting from a major drought in the Sahel. Increasing substitutability across starchy staples, for example through expansion of maize, cassava and sorghum-based convenience foods, would further moderate consumption pressure by expanding the array of food alternatives and hence supply responses available during periods of stress.     

Value of parsimonious nutritional information in a framed field experiment

This study investigates consumers’ beliefs about the tastiness and healthiness of 173 food items in a framed field experiment designed to mirror a grocery shopping environment. Using data collected from 129 food shoppers in Grenoble, France, demand models are estimated to determine how product choice is affected by price, taste, and perceived healthiness, and how choices change with the provision of objective health information. Unlike previous studies focusing on relatively complex nutrition labels, we elicit and convey health information using simple nutritional indices meant to lower search and cognitive processing costs. The results indicate that consumers are willing to pay for tastier foods and for healthier foods, particularly if the consumers have objective information (as opposed to perceived, subjective information) on nutrient content. The estimates suggest that the value of the type of nutritional information provided in the experiment is €0.98 per day. The figure refers to the daily welfare benefits that arise from being able to make a set of choices that better reflect people’s preferences by receiving the nutrient index information on all 173 food items versus not having such information.     

Bargaining power,decision making,and biofortification: The role of gender in adoption of orange sweet potato in Uganda

We examine the role of gender dimensions of intrahousehold bargaining power and decision making in the adoption and diffusion of orange sweet potato (OSP), a biofortified crop being promoted to increase dietary intakes of vitamin A in Uganda. We use patterns of ownership and control of land and other assets by married men and women to create gender-disaggregated indicators of bargaining power, allowing for joint and sole ownership and control of land and assets. Using data from an experimental evaluation of a project promoting OSP adoption, we find that the probability of adopting OSP is not affected by the exclusive or joint control of assets by women at the household level. However, within households, parcels of land under joint control, in which the woman has primary control over decision making, are significantly more likely to contain OSP. Women who control a higher share of household nonland resources are more likely to share OPS vines, showing that women use greater bargaining power to facilitate diffusion of this health-promoting technology. We do not find any impact of women’s bargaining power on children’s dietary intakes of Vitamin A, possibly because husbands and wives have the same preferences regarding their children’s nutritional status. These results contribute to reshaping our understanding of household decision making to inform the design and implementation of agriculture-nutrition interventions.     

Dynamic Product Diversity

This paper examines the frequency of new product introductions in monopoly markets where demand is subject to temporary satiation. Consumers' taste for diversity is satisfied over time as new varieties are introduced to the market. If two varieties are introduced in consecutive periods then they become imperfect substitutes and the firm has an incentive to raise prices and sell each one to consumers with higher valuations (better preference matching). Higher frequency can also generate market expansion. However, under strong temporary satiation, better preference matching may dominate and the frequency of new product introductions may become socially excessive.     

Monopolistic competition and a firm's product range

A model is presented which assumes that firms maximise profits with respect to both the number of varieties supplied as well as the output level of a typical variety. The incentive to produce more than one variety comes from a cost advantage due to inter-product economies. It is found that in a long-run free-entry equilibrium the industry is characterised by too few product varieties and each variety is over supplied compared to the welfare maximum for any conjectural variation elasticity. The former result also holds if the number of firms is held fixed.     

Developing viable farmers markets in rural communities: An investigation of vendor performance using objective and subjective valuations

Farmers markets are drawing increasing attention by consumers as a local source of fresh foods; by producers as an alternative marketing opportunity to improve farm sales; and by policy makers concerned about the limited availability of affordable, nutritious foods in low-income, sparsely-populated rural areas. Using unique data collected from customers, vendors, and markets in a rural region of New York State, we develop an empirical model of subjective and objective measures of vendor performance to identify important factors for improved market sustainability. The empirical results suggest four inter-related planning recommendations when considering market and public policy interventions: (1) establishing larger, centrally located markets with public sector contributions, (2) targeting variety in products and vendors, (3) prioritizing attention to marketing and promotion, and (4) reducing cost burdens to underserved, low-income residents. As rural areas are spatially unique, future research across a variety of rural communities and regions will be important to the further development of sound initiatives aimed at improving market performance and access to healthy foods.     

Conceptual problems in nutrition education in Western Nigeria

A pilot survey of the factors affecting infant feeding practices in rural Western Nigeria highlights intercultural perceptual problems. Results show widespread use of imported, high cost carbohydrate foods and great resistance to the early introduction of local health protective items. It is commonly thought that "too much food" is bad for a child. Staff responsible for health education are held in a degree of disrepute not conducive to the acceptance of their educational efforts in the community. Recommendations include control of advertising; reviewed staff orientation and training; and an intensive campaign to reestablish breast feeding as the cultural norm. No data is presented on feeding of fluids (breast milk, additional milk, boiled water and glucose in water) and nonfluids (imported carbohydrate, local carbohydrate, local protein and fruits and vegetables) based on the mother's estimate of the age of a baby shown in a photograph. Approximate market prices of imported commodities commonly used for infant feeding in the study area are also included.     

Quality certification vs. product traceability: Consumer preferences for informational attributes of pork in Georgia

Consumer willingness-to-pay for informational attributes of food products is important information for food producers and supply chain participants and policy makers. We examine consumer demand in the pork sector of the Republic of Georgia. Results of conditional and mixed logit estimation, conducted on choice experiment data, reveal that Georgian consumers treat quality certification and product traceability attributes as substitutes. We also find that producers and other supply chain participants should be concerned primarily with maintaining the appearance of pork products. Retailer specific factors such as location and type of outlet can also substitute for product traceability. Store location and product appearance, however, are complementary attributes. In light of the recent turbulence in Georgia these consideration may be of paramount importance as participants in the supply chain seek to rebuild damaged infrastructure.     

Adoption of improved maize varieties in Southern Ethiopia: Factors and strategy options

This paper identifies factors that influence the decision behavior of farmers in Southern Ethiopia in adopting improved maize varieties by estimating a logistic regression. Data for this study came from 222 farmers interviewed as part of a national adoption survey conducted in three selected maize growing administrative zones of Southern Ethiopia in 1998. The paper also assesses the impact of pure and mixed strategy options on the probability of adoption of improved maize varieties through simulation under different scenarios. As far as pure strategies are concerned, the credit strategy is more powerful than the others in terms of raising the probability of adoption. However, results from the analysis of pure versus mixed strategies imply that mixed strategies are no necessarily much better than pure strategies.