Consumer valuation of improved rice parboiling technologies in Benin

https://doi.org/10.1016/j.foodqual.2011.07.005Get rights and content

Abstract

In Benin, traditional parboiling is still widely practiced among rice processors, resulting in inferior grain quality. A new parboiler was introduced to improve the milling yield and intrinsic quality of local rice. We conducted Vickrey second price auctions to elicit rural Beninese consumers’ willingness to pay for rice obtained through the new parboiler and two locally innovated parboilers. The individual auctions were followed by a group discussion during which consensus was reached on socially acceptable prices. Relative to traditionally parboiled rice, consumers were willing to pay price premiums of 9–13% for rice obtained through a local parboiler using a container of which the bottom is a perforated metal, 27% for rice obtained through a local parboiler using wooden sticks at the bottom of the pot, and 25–34% for rice parboiled through the improved parboiler. Bids were influenced by the presentation order of the products according to perceived quality. Bids were also higher when participants had been informed on the benefits of improved parboiling techniques, which is a crucial insight for developing marketing and communication strategies for this improved quality product. Group bids were not significantly different from individual bids which suggests that the latter are within the range of socially acceptable prices defined through group consensus.

Highlights

► Consumers’ valuation of parboiled rice is elicited through experimental auctions and group consensus. ► Beninese consumers bid significant price premiums for improved parboiled rice. ► Bids are affected by the time of the day, but unaffected by sensory experience. ► Bids are affected by the presentation order of the alternative rice qualities. ► Bids were within the range of socially acceptable prices determined through group consensus.

Introduction

Rice is a staple food throughout West Africa and growth in rice demand as a preferred staple is so strong that production intensification and increasing yields will not be sufficient to bridge the widening gap between domestic demand and supply. Rice consumption in Benin has increased since the 1960s according to an impressive annual growth rate of 21%, i.e. the highest rate recorded in sub-Saharan Africa (Rutsaert, Demont, & Verbeke, 2012). In 2008, it reached the level of 218,000 tons, while domestic production only attained 65,000 tons of milled rice and, hence, satisfied only 30% of the country’s demand (FAO, 2010). In addition, urban consumers have developed a preference for imported rice, mainly because of its superior perceived quality (Rutsaert et al., 2012, Seck et al., 2010). This has slowed down the development and implementation of policy measures to stimulate local rice production and processing. Measures that address the quality of local rice could reverse this trend to the benefit of local rural producers (Demont and Neven, 2012, USAID, 2009). Parboiling of rice is a possible treatment of raw paddy that can enhance the physical, chemical and organoleptic quality of rice.

Issues of rice availability in Africa have to be addressed from a broad perspective that takes into account the technologies as well as the socio-institutional context of food production and consumption (Demont, 2010, Nwanze et al., 2006). Knowing how consumers react to different qualities of locally processed rice will help to gain insights in how to promote innovations that improve product availability and quality (Demont and Neven, 2012, USAID, 2009). Women, the target group of our study, are the major decision-makers in rice purchase in Benin and the wider region (Fall et al., 2007, Tomlins et al., 2007, Lançon et al., 2003, Lançon.et al., 2001, Tomlins et al., 2005). The main objective of this study is therefore to elicit rural Beninese consumers’ willingness to pay (WTP) for rice qualities obtained through alternative parboiling techniques, namely traditional parboiling compared with three alternative methods, including two locally innovated parboilers, as well as one improved parboiler developed by INRAB and Africa Rice Center.

Parboiling is a hydrothermal treatment applied to raw paddy that can enhance the physical, chemical and organoleptic quality of rice. This process involves the three basic processes of soaking, steaming and drying (Chukwu, 1999). During this process, the physical properties of the grain change as starch gelatinizes because of the heat treatment in the presence of water (Islam et al., 2001, Rao and Juliano, 1970). These physical changes in the physicochemical properties of rice affect the later processing operations of storage, milling, cooking and eating qualities. The lipase in the bran layer of brown rice becomes inactivated due to the heat treatment, which improves the shelf life of parboiled brown rice by reducing the tendency for oxidative rancidity. The benefits of parboiling are an increase in total head yield of paddy, reduction of loss of nutrients during milling, salvaging of damaged paddy and reduced incidence of breakage during milling, reduced stickiness of the cooked rice and the improved cooking behavior of the parboiled rice. Cooked parboiled rice grains are significantly more intact and retain their natural shape as compared to non-parboiled grains. On the other hand, parboiling rice adversely affects some of the nutritional contents of the product (Chukwu & Oseh, 2009).

In Benin and many other West African countries, rice parboiling is exclusively done by women and girls from rice producing villages and surrounding areas. Rice production and processing tasks are divided on the basis of gender, with women being responsible for much of the work involved in processing (Norman & Kebe, 2006). Rice processing is a viable vehicle to empower women by providing them with livelihood and micro-enterprise opportunities. Thus, better processing technologies may directly improve the lives of women and advance their position and respect in rural communities.

However traditional parboiling does not consistently lead to good quality rice because processors are often poorly aware of the basic technicalities of parboiling, despite its simplicity (Diop, Hounhouigan, & Kossou, 1997). Paddy is often pre-cooked with excess water, which can have deleterious effects in terms of quality (Behrens, Heinemann, & Lanfer-Marquez, 2007). The prevailing traditional method in Benin results in low milling yield and poor quality. During traditional rice parboiling, paddy rice is poured directly into the pot with water, and grains at the bottom burn and are not uniformly pre-cooked. At the end of the steaming, moisture content is higher and not uniform. Paddy steamed using this method requires a longer time to dry completely and the rate of cracks is increased thereby causing lower yield. The higher presence of cracks or burnt paddy rice in the final product lowers its quality (Houssou & Amonsou, 2004). This can also negatively affect the nutritional value of rice (Diop et al., 1997). To enhance the quality of parboiled rice, researchers from INRAB (The National Agricultural Research Institute) and Africa Rice Center (AfricaRice, ex-WARDA) collaborated with local artisans and female rice processors to develop an improved parboiler with local materials and equipment. The improved parboiling equipment consists of a large, metal pot with a perforated bottom that is placed on top of a large aluminium pot containing water (Fig. 1). The equipment can be made by local artisans with available materials and skills. The principle behind this improved technology is that after soaking the paddy, it is transferred to the top container and pre-cooked with steam, without the paddy touching the water (Zossou, Van Mele, Vodouhe, & Wanvoeke, 2009). The improved parboiler enhances product-related quality (notably better moisture content, lower rate of cracks, and lower rate of burnt grains) (Houssou & Amonsou, 2004). AfricaRice subsequently developed a video where rural women explain how to use this improved technology and its benefits (Van Mele, 2006).

The two most frequently encountered local innovations to separate the paddy from the water during steaming were: (i) the use of a perforated metal base adapted to a pan, hereafter referred to as the “perforated-base parboiler,” and (ii) the placement of wooden sticks at the bottom of the pot that are covered with a bag before putting paddy for parboiling, hereafter referred to as the “wooden-sticks parboiler” (Fig. 1).

Studies on consumer preferences and acceptability of parboiled rice are scarce. Tomlins et al. (2005) investigated consumer preferences for locally produced versus imported parboiled rice and related sensory attributes with consumer acceptability of rice through consumer surveys and sensory panels in three urban centers in Ghana. Similar to urban Benin, parboiled rice produced in Ghana is of poor quality and is being overtaken by imported rice. The authors observed that acceptability of rice is mostly influenced by the brown color of the cooked rice and unshelled paddy in the raw rice. Heinemann, Behrens, and Lanfer-Marquez (2006) analyzed acceptability and consumer attitude towards parboiled rice in Brazil using sensory panels and consumer surveys. They concluded that the majority of consumers do not reject the parboiled rice solely based on its sensory properties, but for not being familiar with it and so, unaware of its characteristics and advantages. In a follow up study Behrens et al. (2007) used cluster and correspondence analysis to identify and profile consumer segments and observed that a positive attitude was a reflection of habit and liking, while a negative attitude was attributed to previous negative experience and misconceptions about the product. Their findings corroborate the need for an increased attention for rice quality, together with marketing efforts and information campaigns in order to inform consumers about the nutritional value and convenience of parboiled rice. Tomlins et al. (2007) evaluated consumer acceptance, affordability and market value of rice parboiled with an improved prototype rice-parboiling vessel in urban Ghana. Their findings suggest that there is a trade-off between improving sensory attributes to increase market price and increasing affordability which is associated with sensory attributes related to poor quality. Sensory attributes associated with quality were positively related with price but negatively with affordability.

The available evidence on consumer acceptability of parboiled rice is based on contingent valuation methods in which consumers state their preferences. Harrison and Rutström (2008) however demonstrated that in stated preference methods participants typically overstate their true valuation. Chowdhury, Meenakshi, Tomlins, and Owori (2011) extend the validity of this finding to the African context and show that valuations of biofortified foods in Uganda are overstated in hypothetical transactions. To avoid this bias, in this article we use an experimental auction market designed to elicit revealed preferences for alternative parboiled rice qualities. Because real products and real money are exchanged in an experimental setting, participants have increased incentives to reveal their true value for a product.1 Surprisingly, little experimental auction evidence is available on developing countries. Notable exceptions are Corrigan, Depositario, Nayga, Wu, and Laude (2009), who compare open-ended choice experiments and experimental auctions to estimate consumer demand for biofortified rice in the Philippines and De Groote, Kimenju, and Morawetz (2011), who use experimental auctions to assess consumers’ WTP for yellow and biofortified maize in Kenya.

Any strategy of food quality upgrading in a food insecure country needs to take into account the trade-off between adding value to improve market price and increasing affordability (Tomlins et al., 2007). Therefore, it would be interesting if the social component could be somehow integrated in the elicitation of value. One way to do this would be to follow individual experimental auction rounds by a consensus session (Bonner, Sillito, & Baumann, 2007), during which participants are requested to achieve a consensus on their collective valuation (collective WTP or CWTP) of the alternative rice types. From a psychological point of view, “value” is a judgment (Oliver, 2006) and grouping of individuals provides a mechanism for including diverse personal preferences and expertise in social judgment processes (Davis, 1973, Davis, 1996), such as for example achieving consensus on CWTP. The mechanism is called “collective induction” and is defined as “the cooperative search for descriptive, predictive, and explanatory generalizations, rules, and principles” (Laughlin & Hollingshead, 1995, p. 94). The absolute values of CWTP are not our primary focus here, but to the extent that they can be interpreted as socially acceptable prices, they provide a “social cross-check” for the individual WTPs. If there is no divergence between both values, this may suggest that the individual WTP values are within the range of socially acceptable prices.

To the best of our knowledge, consumer valuation of improved parboiled rice in Africa has never been assessed through experimental auctions and group consensus, which constitutes a major rationale for the methodological approaches in our study.

Section snippets

Overall setting

We selected the market of Glazoué, an important rural market in the Collines department in central Benin, where parboiling is a major economic activity (Zossou et al., 2009). In a first stage, we identified the most popular local rice variety in the test area, which is gambiaka. We used this variety for the entire experiment. A total of four women groups were selected to parboil the rice under the supervision of four facilitators. Rice was parboiled in the villages under local conditions using

Sample characteristics

Table 1 shows some summary statistics of the socio-demographic characteristics of the sample. Women were on average 37 years old and could be categorized into two major ethnic groups, i.e. Yoruba (59%) and Fon, including Mahi and Minan (41%). The average monthly household income was 46,000 FCFA (US$93) and was used to feed five individuals on average. The education level was fairly low; only 12% had been educated beyond primary school. As discussed before, we accounted for the high illiteracy

Acknowledgements

Financing from the Government of Japan and the European Union is greatly acknowledged. We are grateful to Bernard Dossou-Yovo (animator, NGO Castor Appuis-Conseils) and Hyacinthe Assogba (animator, NGO Un Monde) for their valuable translation and animation services during the experiments.

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