The review followed a systematic search in PubMed and Scopus databases. A search strategy was developed in consultation with a research librarian at De Montfort University, Leicester. Search terms included consumer OR individual OR market OR adult AND acceptance OR acceptability OR liking OR rating OR preference OR sensory evaluation OR choice OR Willingness to pay AND indigenous OR local OR traditional OR native OR orphan OR neglected OR wild OR underutilised OR ancient AND vegetable OR fruit OR crops OR foods OR plants OR greens AND sub-Saharan Africa OR Africa OR tropical Africa. Specific searches were conducted for each country in the SSA. The search was done following the inclusion criteria up to October 2024.

The study selection method outlined in Table 1 was used to identify potential publications. The number of included and excluded articles is presented in a search decision flowchart, following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) (Fleming et al., 2013) as shown in Figure 1. The eligibility criteria for studies (Table 1) follow the SPIDER tool (Cooke et al., 2012), that is Sample [S], Phenomenon of Interest [PI], Design [D], Evaluation [E], and Research type [R].

All identified literature was exported to RefWorks reference manager in the Research Information Systems (RIS) format. After removing duplicates, all literature was exported to Rayyan, a systematic review screening tool, and screened based on title, abstracts, and key terms. Only English-language articles were included in the review. Two reviewers (NB and MGE) independently screened the studies, and any conflicts were discussed until consensus was reached. If consensus could not be achieved, a third researcher was consulted. Full-text examinations were then conducted for studies meeting both the inclusion and exclusion criteria, following the same process for resolving disagreements.

Data was charted in an excel sheet including the following: publication year, study objective (s), study region and country, types of vegetables/fruits studied, citation, target population for study, sample size, years of data collection, study design and data collection method, duration of study period, methodology for consumer acceptance, main findings, methodological limitation, coherence, adequacy of data, and relevance.

In the final screening phase, content analysis was conducted to further assess eligibility. We adapted the Quality Assessment for Diverse Studies (QuADs) tool by Harrison et al. (2021) by selecting only the items relevant to our review objectives to determine the quality of included studies. Rather than performing a full critical appraisal, which was not appropriate for this type of review, we focused on specific criteria to identify study quality. Responses to the adapted appraisal questions guided the final decisions to include or exclude full-text articles for data synthesis that had advanced through PRISMA screening steps. One author independently appraised all studies, and all authors reviewed and approved these appraisals. Studies were excluded if they lacked a clear statement of objectives, used a study design inappropriate for addressing the research questions, applied unsuitable analytical methods, or, in the case of quantitative evaluation studies, had a sample size smaller than 75 (Drake et al., 2024).

Both quantitative and qualitative (thematic) analyses were employed to synthesize findings from the studies included in the systematic review. The descriptive analysis involved examining the frequency of publications by year, country, and across various regions within SSA to highlight geographic patterns and the diversity of indigenous plant species evaluated across the literature. Additionally, the number of times each indigenous vegetable or fruit appeared in the studies was tallied. A separate descriptive summary was conducted for consumer acceptance studies, focusing on the types of sensory tests used.

Inferential analysis was presented using effect direction plots (Thomson and Thomas, 2013) of consumer preference. This was assessed by comparing participant evaluations of foods containing African IFV to control versions without African IFV or to versions prepared using different cooking or processing techniques. A positive effect direction indicated that the African IFV-enriched foods were more favourably rated than the controls; a negative direction indicated lower ratings; and a neutral direction suggested no difference in acceptance.

A thematic analysis was conducted to explore the determinants for consumer acceptance and preference for African IFV. Two iterative coding stages were used. First, open coding was applied to extract key ideas and recurring concepts across studies. In the second round, these codes were grouped into broader categories based on similarity, resulting in a final set of themes and sub-themes. These were visualized using a thematic map with color-coded categories for clarity. The results were summarized according to these themes.

Overall, 2,934 studies were retrieved from the initial search from two databases (PubMed n = 643; Scopus n = 2,291). After title and abstract screening, a total of 55 studies met the inclusion criteria as shown in Figure 1.

Using the QuaDs tool (Harrison et al., 2021), the quality of included studies was appraised by examining key methodological criteria rather than assigning overall quality scores. Research aims were generally well reported with studies stating objectives that were aligned with their respective research themes. However, few studies situated their work within theoretical or conceptual frameworks which limited the depth of interpretation and the broader applicability of findings beyond the immediate experimental context. Reporting on sampling approaches and participant characteristics was often less comprehensive. When assessed against the sample size criterion, many studies were found to be inadequate relative to established sensory science standards. According to Lawless and Heymann (2010) and Civille and Carr (2015), quantitative consumer tests evaluating two to four food samples should ideally include 75–100 participants to ensure statistical reliability and reduce bias. Only a few studies such as (Ntila et al., 2019) with 120 participants, (Sangija et al., 2022) with 370 participants, (Agúndez et al., 2018) with 432 participants, (Gido et al., 2017a) with 450 participants, and (Atuna et al., 2022) with 1,393 participants, met these thresholds, providing sufficient power for valid inferences.

Most of the included quantitative sensory and consumer acceptance studies used very small sample sizes, often ranging between 15 and 50 participants. Such small sample sizes fall below the recommended standards for quantitative consumer testing, limiting representativeness and the robustness of statistical conclusions. Although a smaller sample size may be acceptable for qualitative sensory profiling or preliminary product development, many of these studies reported quantitative outcomes for example, p-values and mean hedonic scores suggesting they were positioned as inferential tests. These findings underscore the need for future research on African IFV to adopt more standardized and transparent reporting practices.

Several studies indicated that consumer acceptance and preference for African IFV are primarily influenced by social perceptions and stigma (Figure 4). In some studies, the consumption or sale of African IFV was associated with poverty, backwardness, or primitiveness, particularly among younger and urban populations (Onyeoziri et al., 2018; Quaye et al., 2009). In Ghana, some African leafy vegetables are considered as weeds (Quaye et al., 2009). Specific vegetables, such as red amaranth, are linked to intra-household conflict or seen as undesirable due to their perceived social connotations (Nyonje et al., 2022). In contrast, the perceived nutritional and medicinal attributes of African IFV are consistently reported as key facilitators of acceptance. Across various regions, African IFV are believed to confer a range of health benefits, including the treatment and prevention of common ailments such as anaemia, diarrhoea, constipation, childhood malnutrition, among others (Chacha and Laswai, 2020; Quaye et al., 2009; Sitotaw et al., 2020; Termote et al., 2010). Certain African IFV such as spider plant, moringa, and amaranth are specifically noted for their functional health properties, including immune-boosting effects, enhancement of lactation, and support for ocular and digestive health (Ntila et al., 2019).

Other determinants include organoleptic properties (sensory characteristics of food that can be perceived by the senses), availability and affordability, preparation complexity, and intergenerational knowledge transmission (Lawal et al., 2021). While some adults appreciate the unique flavors of African IFV, others reported aversions due to bitterness or undesirable textures (Sitotaw et al., 2020; Thovhogi et al., 2021). Although African IFV are often more accessible and cost-effective than exotic vegetables in some regions of SSA (Chacha and Laswai, 2020), limited availability of staple food accompaniments and labour-intensive preparation processes are reported to be practical barriers (Lawal et al., 2021).

Consumer acceptance levels were variable, reflecting diverse responses across study populations. While several studies demonstrated positive acceptance of dishes incorporating IFV, a notable proportion reported preferences for meals without them. All accepted products containing IFV were incorporated into familiar foods such as meatloaf, bread, porridge, swallow, nut-based beverages, soups, and salads. Embedding IFV within formats that consumers already recognize and commonly consume increases acceptance, suggesting that the familiarity of the food vehicle potentially reduces resistance towards underutilised fruits and vegetables. Unfamiliarity with a food often gives rise to food neophobia, defined as the reluctance or avoidance of consuming novel foods (Pliner and Hobden, 1992). The incorporation of IFV is most effective when paired with an appropriate food vehicle. For instance, oyster mushrooms enhanced the acceptability of chicken meatloaf (Olabinke et al., 2024), whereas their addition to biscuits reduced consumer preference (Owheruo et al., 2023a). This highlights the importance of aligning IFV with compatible carriers to optimize both sensory appeal and consumer acceptance. On the other hand, food prototypes containing smaller quantities of IFV were generally more accepted than those with higher levels of incorporation (Melese and Keyata, 2022; Mezajoug Kenfack et al., 2023; Uckert et al., 2023). In several cases, control prototypes with 0% IFV received the highest overall liking scores (Adedokun et al., 2022; Alozie and Ene-Obong, 2018; Diddana et al., 2021; Lawal et al., 2021; Mungofa and Beswa, 2024; Olagunju et al., 2022; Olusanya et al., 2023), indicating that consumer preference tends to increase when only modest amounts or no IFV are added to foods.

Current efforts to improve fruit and vegetable intake often focus on nutrition education and availability (Azupogo et al., 2025), yet persistent barriers, such as unfamiliar sensory attributes, limited food literacy, and negative perceptions continue to constrain consumption (Babirye et al., 2025; Stadlmayr et al., 2023). To address these sensory barriers, incorporating IFV into prepared foods has emerged as a promising strategy. Similar to food fortification approaches, this method varies by food type, cultural context, and country-specific dietary practices. Incorporating a combination of different IFV into a food product may help balance or counteract the undesirable sensory attributes of a single IFV, thereby improving consumer tolerance and potentially increasing overall consumption (Kriesemer et al., 2021; Onyebuchi and Asouzu, 2020; Uckert et al., 2023). Overall, the findings reveal that sensory appeal can be enhanced through careful selection of preparation techniques with certain methods improving flavor, texture, and overall liking, while others reduced consumer preference. Several studies highlighted that leafy vegetables are well accepted when cooked or processed in ways that enhance palatability without altering the food too far from familiar sensory expectations. These preparation techniques are an important dimension of food literacy that shapes how individuals interpret, prepare, and enjoy indigenous foods. For instance, in the case of canned leafy vegetables, amaranth prepared in cream sauce was preferred over that canned in brine (Onyeoziri et al., 2018), suggesting that cream can enhance flavor and texture, thereby improving consumer acceptance. Similarly, sauces made from fresh African nightshade and cowpea leaves were more acceptable than those prepared from dried forms (Ahmed et al., 2023; Ahmed et al., 2023), reinforcing the preference for freshness. Stir-fried African pumpkin leaves were also favoured compared to boiling, steaming, and microwaving (Mashiane et al., 2021), suggesting that cooking methods which retain color, texture, and flavor are more appealing. By contrast, spekboom leaves were only rated neutrally when raw and slightly disliked when cooked, indicating that not all indigenous leafy vegetables are equally adaptable to conventional cooking methods.

Species-specific preferences exist for mushrooms (Agaricus bisporus), Gnetum (Gnetum buchholzianum), and edamame (Glycine max) varieties, suggesting that promoting the right variety can improve uptake. In a recent study from Benin and Mali, consumer preferences were shaped by distinct species-dependent traits. For example, amaranth, jute mallow, and okra varieties with green to dark green leaves or pods were particularly valued and preferred (Mitchodigni et al., 2025). The findings also reveal a complex interplay of cultural, sensory, socio-economic and health-related determinants shaping consumer acceptance and preference of African IFV. Acceptance is higher where traditions are intact and intergenerational transfer of knowledge is strong. Studies show that children who grow up eating meals prepared with indigenous vegetables become accustomed to them, which fosters long-term acceptance. This practical and cultural knowledge, that is, how to cook the IFV, what staple foods to pair them with, and how to reduce undesirable sensory traits is often transmitted within households (Van Der Hoeven et al., 2013). In settings where this transfer of knowledge is disrupted, such as with increasing urbanization, acceptance and use of African IFV are more likely to decline (Paul et al., 2015).

The recurring association of African IFV with poverty, primitiveness, and rural life, especially among younger and urban populations in the included studies reflects a wider process of food socialization where dietary practices become markers of status and modernity (Fischler, 1988). This aligns with theories of food choice that emphasize the symbolic meanings of food (Jones, 2007), suggesting that stigma may represent a stronger barrier to African IFV uptake than affordability or availability alone. Tackling these negative perceptions requires deliberate repositioning of African IFV as modern and health-promoting foods, potentially through co-creating them with traditional staples and integration into urban food spaces.

Most studies (80%) were published after 2017, peaking in 2023 (Figure 2) showing an increasing research attention and recognition of the nutritional, cultural, and economic value of African IFV in SSA. There is a dominance of quantitative approaches mainly relying on hedonic scales, suggesting that methodological diversity remains limited. Geographically, the distribution of studies reveals disparities, with West Africa, particularly Nigeria emerging as the leading contributor, followed by East Africa, while Central Africa remains underrepresented. This pattern contrasts with findings from a systematic review on indigenous crops in SSA, where Southern Africa led with 22 studies, including 10 from South Africa (Ndlovu et al., 2024). This uneven representation may be linked to differences in research infrastructure and funding priorities. Across regions, amaranth consistently stands out as the most studied vegetable, reflecting its versatility, accessibility, and central role in traditional diets. Often described as a low-cost crop, amaranth plays a critical role in enhancing food security, particularly among resource-poor households (Ruth et al., 2021). Other widely studied indigenous vegetables including cowpea leaves, moringa, and baobab leaves, further highlight the central role of leafy vegetables in local food systems. In contrast, indigenous fruits were underexplored despite their nutritional value. This may be linked to environmental pressures such as deforestation driven by population growth, reliance on trees for firewood and charcoal, and, in some contexts, the expansion of commercial activities which undermine the availability and diversity of these species (Cernansky, 2015).

To effectively introduce IFV into dietary patterns, it is essential to understand their acceptability across multiple dimensions. First, it is important to assess how people perceive and accept IFV when consumed on their own, as many IFV may have unfamiliar or strong sensory attributes such as bitterness, pungency, or fibrous textures that can limit direct consumption. Second, evaluating individuals’ willingness to consume commonly eaten foods or staples enriched with IFV is critical, as incorporating these ingredients into familiar dishes may enhance intake while reducing taste-related barriers. However, repeated tasting may be necessary to increase familiarity and overcome food neophobia. Third, understanding how different cooking or processing methods, such as boiling, steaming, drying, fermenting, or blending affects taste, texture, color, aroma, and overall appeal is key to identifying preparation methods that maximize acceptability without compromising nutritional value. Fourth, it is necessary to identify which species or varieties are preferred within a population as consumer preferences can vary by cultural background, region, and familiarity. Addressing sensory barriers, cultural perceptions, and culinary familiarity is therefore essential for designing interventions, educational campaigns, or product formulations that can successfully integrate IFV into everyday diets. Without such an understanding, even highly nutritious IFV are unlikely to achieve sustained uptake, highlighting the need for systematic investigation into consumer acceptability, preferences, and the factors influencing their adoption in dietary patterns.

Limitations of this review include potential publication bias favouring recent and English-language studies, as well as the predominance of quantitative sensory analyses, which may limit deeper understanding of cultural and contextual influences. Challenges encountered included variability in study designs, heterogeneous sensory evaluation methods and reporting of consumer acceptance outcomes. The next step should logically involve directly incorporating and building on the findings of this review. This may offer a more immediate and feasible pathway for advancing IFV research and practice. Future studies should therefore adopt multidisciplinary, culturally sensitive approaches that integrate sensory science with ethnographic, behavioural, and economic perspectives. Investigations into strategies for stigma reduction and market integration, especially in urban settings, are crucial for unlocking the full potential of African IFV to contribute to food security, nutrition, and sustainable livelihoods across SSA.

This review offers a comprehensive and original synthesis of consumer acceptance and preference for IFV across SSA, revealing trends and patterns that were previously underexplored in such detail. In line with the objectives of the review, the findings demonstrate that consumer acceptance of IFV is strongly shaped by food familiarity, sensory attributes (taste, texture, and appearance), and deeply rooted cultural norms. The review also highlights the critical role of food vehicles and preparation techniques in enhancing palatability, acceptability, and willingness to consume IFV, particularly among younger and urban populations.

Despite their nutritional and cultural value, there is persistent stigma framing IFV as “foods of the poor” or symbols of primitiveness causing a major socio-cultural barrier to wider adoption. Addressing this stigma requires deliberate and context-specific repositioning strategies that reframe IFV as desirable, modern, and health-promoting foods rather than survival foods.

Based on these findings, recommendations to improve IFV consumption include considering interventions that prioritize their familiarity and sensory appeal. Such interventions include the use of culturally acceptable recipes, improved preparation methods, and incorporation of IFV into commonly consumed dishes. Co-creation of recipes with communities, particularly women and youth, is recommended to ensure acceptability and sustainability. Secondly, food environment strategies should promote innovative food vehicles, such as snacks, and minimally processed IFV products to enhance convenience and align IFV consumption with contemporary lifestyles. These approaches may be particularly effective in urban and peri-urban settings where traditional preparation practices are declining.