Consumer acceptance of yellow, provitamin A-biofortified maize in KwaZulu-Natal

Sensory acceptability of biofortified foods and food products: a systematic review

CONTEXT

It is important to understand the sensory acceptability of biofortified food products among target population groups if biofortification is to be realized as a sustainable strategy for mitigation of micronutrient deficiencies, able to be scaled up and applied through programs.

OBJECTIVE

This systemic review aims to summarize and synthesize the sensory acceptability of conventionally bred iron-, zinc-, and provitamin A-biofortified food products.

DATA SOURCES

MEDLINE (PubMed), AGRICOLA, AgEcon, CABI Abstracts (Web of Science), and organizational websites (eg, those of HarvestPlus and CGIAR and their partners) were searched for relevant articles. No access to any market research that may have been internally conducted for the commercial biofortified food products was available.

DATA EXTRACTION

This review identified articles measuring the sensory acceptability of conventionally bred biofortified food products. Extraction of the hedonic ratings of food products was performed.

DATA ANALYSIS

An "Acceptability Index %" was defined based on hedonic scoring to determine an overall rating, and used to categorize biofortified food products as "acceptable" (≥70%) or "not acceptable" (<70%). Additionally, this review narratively synthesized studies using methods other than hedonic scoring for assessing sensory acceptability.

CONCLUSIONS

Forty-nine studies assessed the acceptability of 10 biofortified crops among children and adults, in mostly rural, low-income settings across Africa, Latin America, and India; food products made from mineral and provitamin A-biofortified food products were generally acceptable. Compared with studies on provitamin-A biofortified food products, few studies (1 to 2 each) on mineral-enhanced crops such as rice, cowpeas, lentils, and wheat were found, limiting the generalizability of the findings. Similarly, few studies examined stored biofortified food products. Few commercial food products have so far been developed, although new varieties of crops are being continuously tested and released globally. Certain crop varieties were found to be acceptable while others were not, suggesting that particular varieties should be prioritized for scale-up. Determining sensory acceptability of biofortified food products is important for informing programmatic scale-up and implementation across diverse populations and settings.

Beta-Carotene Retention and Consumer Acceptability of Selected Products Made from Two Provitamin-A Maize Varieties

A study was carried out to determine beta-carotene retention and acceptability of selected products made from two provitamin-A maize varieties grown in Malawi, namely, MH43A and MH44A. Beta-carotene retention in the provitamin-A maize products was determined by using a "completely randomised block design" (CRBD) whereby the maize varieties (replicates) were treated as fixed blocks, and similar treatments (analytical tests) were applied in each block. Acceptability of the provitamin-A maize products was determined in 6 to 23-month-old children and their caregivers using a cross-sectional design. Results showed that in three maize products, namely, porridge, maize meal, and fermented maize beverage, there was an increase in beta-carotene, with apparent retentions of 111.13%, 170.27%, and 138.22% for MH43A and 156.50%, 207.13%, and 126.17% for MH44A varieties, respectively. Results on pregerminated maize flour produced from MH43A and MH44A maize varieties showed lower beta-carotene apparent retention values of 63.3% and 84.7%, respectively. Results on acceptability showed that most of the caregivers (47.1%) preferred porridge prepared from MH43A flour compared to porridge prepared from MH44A (30.6%) and the control variety (MH26-white maize) (22.4%). For roasted maize, roasted white maize grains (49.6%) were more preferred compared to the two provitamin-A varieties. Results on acceptability with respect to children showed that most children (63.5% and 53.7%) who tested MH43A and MH44A porridge, respectively, consumed all the porridge. Results from this study have shown that there is a high acceptability of provitamin-A maize porridges amongst children prepared from MH43A (55.5%) and MH44A (51.9%) maize varieties. The study therefore recommends that provitamin-A maize varieties should be promoted through appropriate preparation methods that ensure high beta-carotene retention to address vitamin-A deficiency.

The Effect of Adding Bambara Groundnut (Vigna subterranea) on the Physical Quality, Nutritional Composition and Consumer Acceptability of a Provitamin A-Biofortified Maize Complementary Instant Porridge

Undernutrition is prevalent in developing regions, particularly sub-Saharan Africa (SSA), especially among children under five. Biofortification of staple crops and using indigenous and traditional crops could be an affordable and sustainable strategy together with other existing strategies to reduce undernutrition. This study aimed to determine the effect of adding bambara groundnut (BGN) on the physical quality, nutritional composition and consumer acceptability of a provitamin A-biofortified maize (PVABM) complementary instant porridge. The PVABM flour was substituted with flour of either red or brown BGN variety at 0, 10, 20 and 30% (w/w) levels. The composite flours were used to make an instantized complementary porridge. The physical quality (texture, color, water absorption capacity (WAC), solubility index (SI) and swelling volume (SV)) of the grains and the composite complementary instant porridges were assessed. Nutritional analysis was conducted using standard AOAC methods. A 55-member consumer panel evaluated the acceptability of the porridge samples using a nine-point hedonic scale. The firmness, WAC, SI and SV decreased with increasing concentration of flour of either of the BGN varieties. The decrease in SV would positively affect the porridge quality as nutrient density and viscosity decreased. The protein, fat, fiber and total mineral (ash) content of the porridges increased with an increase in either BGN variety. There was no significant difference (p > 0.05) in the overall acceptability of the BGN–PVABM composite porridge samples and the porridge without BGN (control). The improved nutritional composition and positive consumer acceptability of BGN–PVABM are encouraging as consumption could contribute to the alleviation of nutrient deficiencies, including protein-energy malnutrition and mineral deficiencies, especially in SSA.

Acceptability of orange corn-common bean as an alternative to corn-soybean complementary porridge in Malawi

This study assessed the acceptability of porridge from a corn-common bean flour blend to increase the diversity of complementary foods in Malawi. Porridges prepared using commercial corn-soybean flour (C-CSB), homemade orange corn-soybean flour (H-CSB), and orange corn-common bean flour (CCBB) were evaluated by 101 pairs of mothers and their respective children aged from 6 to 24 months. A home use test (HUT) setup was used in this study, and the flours were given sequentially to participating households following a randomized complete block design. Each sample type was evaluated for 3 days in a row followed by a 1-day break (washout period) between sample types. Based on aggregate mean scores, all the samples were liked by both the children and their mothers. However, clustering results revealed two distinct consumer segments for mothers as well as for children. Most of the mothers (59.4% in cluster 1) liked all the samples, while the minority (cluster 2) were neutral (neither like nor dislike) regarding the H-CSB porridge. Likewise, most children (66.3% in cluster 2) liked all the samples, while the rest in cluster 1 did not like CCBB porridge. Infants (≤12 months) and those from food-insecure households, respectively, were 5.42 and 6.75 times more likely to like the CCBB porridge than their counterparts. The study has demonstrated the potential of introducing CCBB complementary porridge in Malawi and possibly in other countries with similar food preferences and socioeconomic stature. PRACTICAL APPLICATION: The study provides a solution to the limited diversity of complementary foods in sub-Saharan Africa and Malawi in particular. The findings can help food scientists, nutritionists, marketers, and policymakers develop strategies for promoting the consumption of orange corn-common bean porridge. Furthermore, the findings can inform decisions on commercializing orange corn-common bean flour by flour processors.

Simultaneous dissection of grain carotenoid levels and kernel color in biparental maize populations with yellow-to-orange grain

Maize enriched in provitamin A carotenoids could be key in combatting vitamin A deficiency in human populations relying on maize as a food staple. Consumer studies indicate that orange maize may be regarded as novel and preferred. This study identifies genes of relevance for grain carotenoid concentrations and kernel color, through simultaneous dissection of these traits in 10 families of the US maize nested association mapping panel that have yellow to orange grain. Quantitative trait loci were identified via joint-linkage analysis, with phenotypic variation explained for individual kernel color quantitative trait loci ranging from 2.4% to 17.5%. These quantitative trait loci were cross-analyzed with significant marker-trait associations in a genome-wide association study that utilized ∼27 million variants. Nine genes were identified: four encoding activities upstream of the core carotenoid pathway, one at the pathway branchpoint, three within the α- or β-pathway branches, and one encoding a carotenoid cleavage dioxygenase. Of these, three exhibited significant pleiotropy between kernel color and one or more carotenoid traits. Kernel color exhibited moderate positive correlations with β-branch and total carotenoids and negligible correlations with α-branch carotenoids. These findings can be leveraged to simultaneously achieve desirable kernel color phenotypes and increase concentrations of provitamin A and other priority carotenoids.

Combining higher accumulation of amylopectin, lysine and tryptophan in maize hybrids through genomics-assisted stacking of waxy1 and opaque2 genes

Waxy maize rich in amylopectin has emerged as a preferred food. However, waxy maize is poor in lysine and tryptophan, deficiency of which cause severe health problems. So far, no waxy hybrid with high lysine and tryptophan has been developed and commercialized. Here, we combined recessive waxy1 (wx1) and opaque2 (o2) genes in the parental lines of four popular hybrids (HQPM1, HQPM4, HQPM5, and HQPM7) using genomics-assisted breeding. The gene-based markers, wx-2507F/RG and phi057 specific for wx1 and o2, respectively were successfully used to genotype BC₁F₁, BC₂F₁ and BC₂F₂ populations. Background selection with > 100 SSRs resulted in recovering > 94% of the recurrent parent genome. The reconstituted hybrids showed 1.4-fold increase in amylopectin (mean: 98.84%) compared to the original hybrids (mean: 72.45%). The reconstituted hybrids also showed 14.3% and 14.6% increase in lysine (mean: 0.384%) and tryptophan (mean: 0.102%), respectively over the original hybrids (lysine: 0.336%, tryptophan: 0.089%). Reconstituted hybrids also possessed similar grain yield (mean: 6248 kg/ha) with their original versions (mean: 6111 kg/ha). The waxy hybrids with high lysine and tryptophan assume great significance in alleviating malnutrition through sustainable and cost-effective means. This is the first report of development of lysine and tryptophan rich waxy hybrids using genomics-assisted selection.

Acceptability of Vegetable Fortified Ugali in Sub-Saharan Africa

Corn flour-based porridge like dough, ugali, is the staple food of low-income population in sub-Saharan Africa. Lack of vitamin A, carotenoids, and dietary fibers brings about serious health issues to this population. In this study, vegetables including bok choy, broccoli, cabbage, carrot, Chinese onion stalk (C_onion), mushroom, are added during the cooking of ugali, as nutritional supplements. The freeze-dried powder of each vegetable was used for its long storage, stable nutrients, and similar particle size. Sub-Saharan African assessors were trained and sensory evaluated the six different vegetable fortified ugali with the plain, unfortified as the control on five attributes. The plain ugali was indistinguishable with the C_onion stalk fortified in color, with the carrot and C_onion stalk fortified in odor, with all vegetables (except broccoli and mushroom) fortified ugali in taste, with carrot and C_onion stalk fortified in granularity, and with cabbage, carrot, C_onion stalk fortified in viscosity. Preference ranking analysis showed that the C_onion stalk fortified ugali is even more favorably preferred than the plain, unfortified ugali, probably due to the umami components in C_onion that serve as the taste enhancer. This study indicates that Chinese onion stalk is a potential vegetable supplement to population in the sub-Saharan Africa.

Evaluation of Oxidative Stability of Full Fat Soybean Flour in Storage and Sensory Quality of Tuo Zaafi-Enriched with Soy Flour as Influenced by Traditional Processing Methods

The oxidative stability of pretreated full-fat soybean flour (FFSF) was evaluated under commercial (Experiment I) and accelerated conditions (Experiment II). In Experiment I, soybeans were pretreated using germination, soaking (24 h), or roasting (110–120 °C), and the dried, milled FFSF was stored for 120 days under commercial storage conditions in two cities in Ghana. Acid value (AV) and peroxide value (PV) were determined. The proximate and sensory quality of Tuo Zaafi, a maize-only dish in northern Ghana enriched with 10–30% of the pretreated FFSF, was assessed. Before storage, all samples had similar PV (1.907–4.305 mEq/kg oil); however, the AV of the germinated sample was higher than that of the unprocessed samples (10.83 vs. 3.13 mgKOH/g oil; p < 0.001). After storage, although AV fluctuated, the PV was similar (2.39–3.74 mEq/kg oil; p = 1.00). Storage location showed no significant differences in terms of AV (4.96–4.97 mgKOH/g oil; p = 0.994), unlike PV (2.07–3.55 mEq/kg oil; p < 0.001). Increasing the levels of the pretreated FFSF in Tuo Zaafi resulted in lower consumer preference scores for all sensory attributes. In Experiment II, FFSF samples (dehulled and nondehulled) prepared from germination, soaking (18 h and 24 h) and roasting were evaluated under accelerated conditions (AC) of controlled temperature (45 ± 0.1 °C) and relative humidity (81 ± 1%) for AV, PV, p-anisidine value (pAV), lipoxygenase activity (LOX), color, and moisture. Pretreatment, condition, time, and their interaction affected the oxidative stability of all FFSF samples (p < 0.001). Roasted samples showed the highest increase in AV and pAV in both storage conditions (p < 0.05). Under room temperature conditions (RTC), the roasted and germinated samples had lower LOX activity (p < 0.05) at the end of storage time compared to that of the controls. In conclusion, germination and soaking reduced oxidation of FFSF, while roasting promotes it, despite its common use.

Carotenoid stability and aroma retention during the post-harvest storage of biofortified maize

BACKGROUND

Maize varieties that are rich in carotenoids have been developed to combat vitamin A deficiency in Sub-Saharan Africa. Unfortunately, after harvest, carotenoids degrade and off-flavor volatiles develop, which affect nutrient intake and consumer acceptance. This study evaluated carotenoid retention and aroma compound stability in provitamin A biofortified maize, variety Pool 8A, as influenced by dry milling and storage in different packaging and temperature conditions.

RESULTS

The lowest amount of total carotenoids was found in flour stored in laminated paper bags at 37 °C (only 16% retention after 180 days), attributable to the high storage temperature and oxygen permeability of the packaging material. No significant effect on carotenoid degradation was found for dry milling, either by rotor mill or freezer mill, but the formation of volatile compounds was significantly (P < 0.05) affected. Volatile compounds such as hexanal, 2-pentylfuran, 1-propanol, 2-heptanone, butyrolactone, limonene, and hexanoic acid were found in different proportions after milling. The highest concentration of hexanal was in flour milled by rotor mill or freezer mill, and stored in laminated paper bags at 37 °C after 180 days, and the lowest concentrations were for flour in aluminium bags and double-layered polyethylene bags stored at 4 °C.

CONCLUSION

Maize flour stored in double-layered polyethylene bags had the highest carotenoid retention and aroma stability. Importantly, the use of these bags is economically feasible in low-income countries. Overall, our results show that effective control of storage conditions is crucial to prevent carotenoid loss and decrease off-odor formation. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Multinutrient Biofortification of Maize (Zea mays L.) in Africa: Current Status, Opportunities and Limitations

Macro and micronutrient deficiencies pose serious health challenges globally, with the largest impact in developing regions such as subSaharan Africa (SSA), Latin America and South Asia. Maize is a good source of calories but contains low concentrations of essential nutrients. Major limiting nutrients in maize-based diets are essential amino acids such as lysine and tryptophan, and micronutrients such as vitamin A, zinc (Zn) and iron (Fe). Responding to these challenges, separate maize biofortification programs have been designed worldwide, resulting in several cultivars with high levels of provitamin A, lysine, tryptophan, Zn and Fe being commercialized. This strategy of developing single-nutrient biofortified cultivars does not address the nutrient deficiency challenges in SSA in an integrated manner. Hence, development of maize with multinutritional attributes can be a sustainable and cost-effective strategy for addressing the problem of nutrient deficiencies in SSA. This review provides a synopsis of the health challenges associated with Zn, provitamin A and tryptophan deficiencies and link these to vulnerable societies; a synthesis of past and present intervention measures for addressing nutrient deficiencies in SSA; and a discussion on the possibility of developing maize with multinutritional quality attributes, but also with adaptation to stress conditions in SSA.

Identification of the volatile profiles of 22 traditional and newly bred maize varieties and their porridges by PTR-QiTOF-MS and HS-SPME GC-MS

BACKGROUND

Low adoption of maize varieties bred to address the nutritional needs of the growing African population limits their impact. Aroma is essential in consumer preference, but has hitherto hardly been studied. We analysed the volatile organic compounds of flours and porridges of 22 maize varieties belonging to four nutritionally distinct groups, namely provitamin A maize, quality protein maize, yellow and white maize.

RESULTS

Proton-transfer-reaction quadrupole ion time-of-flight mass spectrometry (PTR-QiTOF-MS) analysis generated 524 mass peaks ranging from 16.007 to 448.089 m/z. Principal component analysis separated the varieties belonging to the four groups. With headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME GC-MS), 48 volatile compounds were identified in maize flour and 21 in maize porridge, including hexane, nonane, pentanoic acid, 1-octen-3-ol, 1-hexanol, hexanal, nonanal, 2-pentylfuran and 2-heptanone. Volatile compounds such as 1,2,4-trimethyl benzene, associated with thermal degradation of carotenoids, increased in the porridge of yellow and provitamin A maize.

CONCLUSION

The results indicate that PTR-QiTOF-MS and HS-SPME GC-MS combined with multivariate analysis are instrumental to study the volatile aroma compounds of different maize varieties.

Towards Sustainable Diets: Understanding the Cognitive Mechanism of Consumer Acceptance of Biofortified Foods and the Role of Nutrition Information

Micronutrient malnutrition, also known as hidden hunger, continues to affect more than 2 billion people globally. Biofortification, which is a process of breeding staple crops with improved micronutrient contents such as vitamin A, iron, and zinc, offers a cost-effective and sustainable solution in reducing hidden hunger. However, the success of these foods depends on consumer acceptance. In contrast to previous studies, this research focuses on the mechanism of consumer acceptance of biofortified crops that undergo physical changes (i.e., changes in appearance) after biofortification. We use data on 473 Chinese consumers collected through online surveys to examine their purchase intentions for biofortified foods that have visible (vs. invisible) nutrition traits. Using two online surveys, we conduct two studies to reveal the mechanism and antecedents of consumer acceptance of different biofortified foods. In Study 1, we find that consumer purchase intentions vary depending upon the visibility of nutrition traits in biofortified foods. Specifically, consumers exhibit a nutrition-related food neophobia (NFN) regardless of visibility of the nutrition trait in biofortified foods; and a sensory-affective food neophobia (SFN) which is only pronounced when the nutrition trait in biofortified foods is visible. The results of the mediation analysis show that for both types of biofortified foods, NFN mediates consumers’ purchasing intentions. For foods that involve visible changes after biofortification, SFN acts as an additional mediator of consumer purchase intentions. Using ordered logistic regression analysis, we find that both food neophobias have a negative impact on consumer acceptance of biofortified foods. The results of Study 2 confirm our findings and further show that nutrition information moderates the mediation of NFN and SFN, i.e., the negative impact of NFN and SFN on purchase intentions can be reduced by providing nutrition information to consumers. The results of this study have several theoretical and practical implications and are of interest to stakeholders and marketers in the promotion of biofortified foods.

Grain Quality, Provitamin A Carotenoid Profiles, and Sensory Quality of Provitamin A-Biofortified Maize Stiff Porridges

Provitamin A-biofortified maize could contribute to the alleviation of vitamin A deficiency (VAD), which is prevalent in sub-Saharan Africa due to a high consumption of starchy, maize-based diets. Four varieties of provitamin A biofortified maize were studied for grain colour, grain texture, thousand kernel weight, and hectolitre mass. Provitamin A biofortified maize stiff porridges were prepared and their retained provitamin A was determined using lutein, zeaxanthin, β-cryptoxanthin, and β-carotene (all-trans and cis isomers) as standards. Provitamin A concentration in the biofortified porridges ranged from 2.24 to 3.18 µg/g and retention from 91-105%. Descriptive sensory analysis and the 5-point facial hedonic test were used to evaluate the sensory quality of the porridges. The biofortified maize porridges were described as sticky, fine, with high intensity residual grain, and having a slightly bitter aftertaste with a cooked maize flavour and aroma, whereas the intensities of these attributes were insignificant in white maize porridge. About 33% of the consumer sample (N = 60) liked the porridges and 28% disliked the porridges, whilst approximately 38% of the consumers were neutral. The findings suggest that biofortified maize stiff porridge can deliver a significant amount of provitamin A to targeted consumers, but the acceptance of biofortified maize still needs to be improved on.

Biofortified Crops for Combating Hidden Hunger in South Africa: Availability, Acceptability, Micronutrient Retention and Bioavailability

In many poorer parts of the world, biofortification is a strategy that increases the concentration of target nutrients in staple food crops, mainly by genetic manipulation, to alleviate prevalent nutrient deficiencies. We reviewed the (i) prevalence of vitamin A, iron (Fe) and zinc (Zn) deficiencies; (ii) availability of vitamin A, iron and Zn biofortified crops, and their acceptability in South Africa. The incidence of vitamin A and iron deficiency among children below five years old is 43.6% and 11%, respectively, while the risk of Zn deficiency is 45.3% among children aged 1 to 9 years. Despite several strategies being implemented to address the problem, including supplementation and commercial fortification, the prevalence of micronutrient deficiencies is still high. Biofortification has resulted in the large-scale availability of βcarotene-rich orange-fleshed sweet potatoes (OFSP), while provitamin A biofortified maize and Zn and/or iron biofortified common beans are at development stages. Agronomic biofortification is being investigated to enhance yields and concentrations of target nutrients in crops grown in agriculturally marginal environments. The consumer acceptability of OFSP and provitamin A biofortified maize were higher among children compared to adults. Accelerating the development of other biofortified staple crops to increase their availability, especially to the target population groups, is essential. Nutrition education should be integrated with community health programmes to improve the consumption of the biofortified crops, coupled with further research to develop suitable recipes/formulations for biofortified foods.

Hydrothermally Treated Soybeans Can Enrich Maize Stiff Porridge (Africa's Main Staple) without Negating Sensory Acceptability

Maize-based stiff porridge, a starchy protein-deficient staple food, dominates among the populations in sub-Saharan Africa (SSA). Unfortunately, this is often consumed along with leafy vegetables since the majority of the population in this region lack resources for the purchase of high protein animal source foods, a situation that exacerbates protein-energy malnutrition. Considering this, the current study evaluated the effect of enriching maize-based stiff porridge with flour made from hydrothermally treated soybeans on consumer acceptability. A total of nine experimental flours were prepared from maize and maize-soybean mixtures following a 32 factorial design involving two factors, namely maize flour type (whole maize, non-soaked dehulled maize, and soaked dehulled maize) and soybean flour proportion (0%, 20%, and 30%). A total of 125 adult consumers from a rural setting in Malawi evaluated maize-based stiff porridges made thereof using a 7-point hedonic scale. Subsequently, the participants were asked to guess an ingredient that was added to some of the test samples. The 10% and 20% soybean-enriched maize-based stiff porridges scored 5/7 and above, with some being statistically similar to plain maize-based stiff porridges. No participant recognized that soybeans were incorporated into the maize-based stiff porridges. The study has clearly demonstrated the potential of enriching maize-based stiff porridge with hydrothermally treated soybeans without compromising consumer acceptability. This innovation could significantly contribute towards reducing the burden of energy-protein under-nutrition in SSA.

Consumer Perceptions and Acceptability of Traditional Dishes Prepared with Provitamin A-Biofortified Maize and Sweet Potato

Vitamin A deficiency (VAD) is prevalent in South Africa, particularly among predominantly poor rural communities. Provitamin A (PVA)-biofortified crops could be used to address VAD; however, there are challenges of poor consumer acceptability. This study investigated the effect of replacing white maize and cream-fleshed sweet potato (CFSP) with PVA-biofortified maize and orange-fleshed sweet potato (OFSP), respectively, on consumer acceptability and perceptions of traditional dishes of rural communities in South Africa. Consumer acceptability of PVA-biofortified phutu (a crumbly maize porridge) served with either curried cabbage, chicken or bambara groundnut, separately, and boiled OFSP was evaluated by black South African adults (n = 120) using a five-point facial hedonic scale. Focus group discussions (FGDs) were conducted with 56 subjects recruited from the consumer panel to assess consumer perceptions of the food samples. The majority of the participants rated the composite dishes containing PVA-biofortified phutu as "4 = good" and the acceptability of the composite dishes varied significantly (p < 0.05). Compared to other age groups, the 50-59-year age group showed higher preference for white phutu and chicken curry, whereas the 30-39-year age group showed higher preference for PVA-biofortified phutu and chicken curry. The acceptability of OFSP and CFSP was similar. The study participants showed positive perceptions of the OFSP, as well as PVA-biofortified phutu if served with either curried chicken or cabbage. The findings suggest that PVA-biofortified maize and OFSP can replace white maize and CFSP, respectively, in selected traditional dishes of the rural communities studied to alleviate VAD.

'Yellow is good for you': Consumer perception and acceptability of fortified and biofortified cassava products

Vitamin A, an essential micronutrient for health, can be obtained from various food sources including cassava products made from either traditional white cassava varieties fortified with red palm oil containing provitamin A, or new high provitamin A biofortified yellow cassava varieties. Both products have a similar yellow appearance due to the coloured pigmentation of provitamin A. Using a range of methods to provide a comprehensive understanding of sensory acceptability (blind triangle test, sensory profiling, hedonic preference that included Check-all-that-applies and Just-about-right tests), we tested the acceptability and nutritional perception of traditional West-African food dough-like products (eba and fufu) made from biofortified, fortified, or control products made with non-fortified white cassava (n = 7) at three suburban locations near Ibadan, Nigeria on a total of 122 consumers. Biofortified, fortified, and control products could be differentiated blindly confirming that products clearly differed with respect to other sensory characteristics than appearance. Overall biofortified products were better accepted than control and fortified ones. Three classes of consumer preference were identified based on the dislike for control and fortified products, which indicated that acceptance of biofortified products was not a hindrance. On the contrary the traditional fortified product had poorer acceptance and this was due to its less desirable sensory characteristics as demonstrated by Just-about-right Penalty analysis. A majority of consumers (85%) had previous knowledge of biofortified cassava. Consumers associated ‘yellow colour’ with ‘good for eyesight’, ‘good for children’s health’ and ‘new’. More nutritional benefits were attributed to biofortified than fortified products although they had similar provitamin A contents and this demonstrates a bias. We suggest that nutrition promotion campaigns to improve the vitamin A status should also encompass all natural sources of provitamin A, including biofortified and traditional fortified products.

The development and release of maize fortified with provitamin A carotenoids in developing countries

Micronutrient deficiencies have been identified as major public health problems affecting a large part of the world's population. Biofortification of staple crops like maize has been proposed as one of the most cost effective and feasible approaches to combat micronutrient deficiencies. Studies have shown that provitamin A from biofortified crops is highly bioavailable and has the capacity to improve vitamin A status of vulnerable groups. Most people in sub-Saharan Africa subsist on maize and many people may benefit from consumption of provitamin A carotenoid biofortified maize, especially women and children. With the exception of transgenic golden rice, biofortified crops have received considerable acceptance by most communities. Negative perceptions associated with yellow maize do not affect orange maize, which is, for example, well-liked in rural Zambia. With proper policy frameworks and full commercialization, provitamin A maize can address the problem of vitamin A deficiencies among poor nations with maize-based diets.

Acceptance and adoption of biofortified crops in low- and middle-income countries: a systematic review

CONTEXT

Biofortification of staple crops is a promising strategy for increasing the nutrient density of diets in order to improve human health. The willingness of consumers and producers to accept new crop varieties will determine whether biofortification can be successfully implemented. This review assessed sensory acceptance and adoption of biofortified crops and the determining factors for acceptance and adoption among consumers and producers in low- and middle-income countries. PubMed, Scopus, and Web of Science were searched for published reports. Unpublished studies were identified using an internet search. From a total of 1669 records found, 72 primary human research studies published in English or Spanish met the criteria for inclusion. : Data were extracted from each identified study using a standardized form. Sensory acceptability (n = 40) was the most common topic of the studies, followed by determinants of acceptance (n = 25) and adoption (n = 21). Of crops included in the studies, sweet potato and maize were the most studied, whereas rice and pearl-millet were the least investigated. Overall, sensory acceptance was good, and availability and information on health benefits of the crops were the most important determinants of acceptance and adoption. : Changes to the sensory qualities of a crop, including changes in color, did not act as an obstacle to acceptance of biofortified crops. Future studies should look at acceptance of biofortified crops after they have been disseminated and introduced on a wide-scale.

Availability, production, and consumption of crops biofortified by plant breeding: current evidence and future potential

Biofortification is the process of increasing the density of vitamins and minerals in a crop through plant breeding-using either conventional methods or genetic engineering-or through agronomic practices. Over the past 15 years, conventional breeding efforts have resulted in the development of varieties of several staple food crops with significant levels of the three micronutrients most limiting in diets: zinc, iron, and vitamin A. More than 15 million people in developing countries now grow and consume biofortified crops. Evidence from nutrition research shows that biofortified varieties provide considerable amounts of bioavailable micronutrients, and consumption of these varieties can improve micronutrient deficiency status among target populations. Farmer adoption and consumer acceptance research shows that farmers and consumers like the various production and consumption characteristics of biofortified varieties, as much as (if not more than) popular conventional varieties, even in the absence of nutritional information. Further development and delivery of these micronutrient-rich varieties can potentially reduce hidden hunger, especially in rural populations whose diets rely on staple food crops. Future work includes strengthening the supply of and the demand for biofortified staple food crops and facilitating targeted investment to those crop-country combinations that have the highest potential nutritional impact.

Food and Nutrition Insecurity in Selected Rural Communities of KwaZulu-Natal, South Africa-Linking Human Nutrition and Agriculture

Lack of access to nutritious and balanced diets remains a major impediment to the health and well-being of people living in rural areas. The study utilizes a qualitative systematic approach to conduct an environmental scan and review of scientific literature of studies conducted in South Africa, specifically KwaZulu-Natal (KZN). Availability and access to nutritious, diverse and balanced diets were identified as key constraints for achieving food and nutrition security as well as for human health and well-being. This has led to both under- and over-nutrition, with the former, in particular stunting, affecting children under 5 years. A high incidence of over-nutrition, both overweight and obesity, was observed among black African females. In South Africa, poor people rely mostly on social grants and cannot afford a balanced diet. Under these circumstances, agriculture could be used to increase availability and access to diverse and nutritious foods for the attainment of a balanced diet. The wider use of traditional vegetable crops and pulses could improve availability and access to healthy and locally available alternatives. The promotion of household and community food gardens, and the use of nutrient dense crops with low levels of water use, i.e., high nutritional water productivity, offers prospects for addressing malnutrition in poor rural areas.

Staple crops biofortified with increased vitamins and minerals: considerations for a public health strategy

Biofortification of staple crops has been proposed as a strategy to address micronutrient malnutrition, particularly with respect to insufficient intake of vitamin A, iron, zinc, and folate. The World Health Organization, in collaboration with the Food and Agriculture Organization of the United Nations and the Sackler Institute for Nutrition Science at the New York Academy of Sciences, convened a technical consultation entitled "Staple Crops Biofortified with Vitamins and Minerals: Considerations for a Public Health Strategy" in April 2016. Participants of the consultation reviewed the definition of biofortification of staple crops, patterns of crops production, processing, consumption, seed varieties, and micronutrient stability and bioavailability, as well as farmers' adoption and acceptability of the modified crops. Also discussed were economic, environmental, safety, and equity aspects of biofortified crops, as well as legal, policy, regulatory, and ethical issues for the implementation of biofortification strategies in agriculture and nutrition. Consultation working groups identified important and emerging technical issues, lessons learned, and research priorities to better support the evidence of improved nutrition and unintended adverse effects of biofortification. This paper provides the background and rationale of the technical consultation, synopsizes the presentations, and provides a summary of the main considerations proposed by the working groups.

Provitamin A retention and sensory acceptability of amahewu, a non-alcoholic cereal-based beverage made with provitamin A-biofortified maize

BACKGROUND

Vitamin A deficiency is a major public health problem in sub-Saharan Africa. Amahewu is a popular southern African lactic acid fermented non-alcoholic maize-based beverage, which is deficient in vitamin A. In this study, provitamin A retention and sensory acceptability of amahewu processed using provitamin A-biofortified maize and three types of inoculums during fermentation (malted maize, wheat bran and Lactobacillus starter culture) were investigated.

RESULTS

The total provitamin A content of amahewu samples, estimated as β-carotene, β-cryptoxanthin and α-carotene content, ranged from 3.3 to 3.8 g kg(-1) (dry weight). Provitamin A was substantially retained (79- 90% β-carotene equivalent) in amahewu after fermentation. Amahewu samples prepared with added starter cultures had the lowest retention of provitamin A. Consumers (approx. 69%) liked provitamin A-biofortified amahewu either moderately or very much. Principal component analysis of amahewu sensory data showed that 71% of variation was due to maize types and 18% of variation could be due to the inoculum used during fermentation. Amahewu samples prepared using provitamin A-biofortified maize were slightly more liked (mean score: 7.0 ± 1.2) compared to those of white maize reference samples. The use of starter culture combined with either malted maize or wheat bran as inoculum during fermentation improved the taste and aroma of amahewu and hence its acceptability.

CONCLUSION

Provitamin A is substantially retained in amahewu after fermentation. The slightly high acceptability of amahewu prepared using provitamin A-biofortified maize compared to that of white maize thus suggests that fermented product like amahewu can potentially be used to deliver provitamin A to vulnerable individuals.