Muthulisi Siwela

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

Abstract Objectives: To assess the acceptance of popular maize food products (phutu, thin porridge and samp), prepared with yellow, provitamin A-biofortified maize varieties, in 212 subjects between the ages of three and 55 years, from rural KwaZulu-Natal. Design: A cross-sectional study. Method: Preschool, primary school and secondary school subjects were randomly selected from two primary schools and one secondary school, respectively, while adult subjects constituted a convenience sample. Pre- and primary school children completed a paired preference test. Secondary school and adult subjects completed a five-point facial hedonic and a preference ranking test. Focus group discussions were conducted using adult subjects. Results: Preschool children preferred yellow maize to white maize food products: phutu (81% vs. 19%; p-value < 0.001), thin porridge (75% vs. 25%; p-value < 0.001) and samp (73% vs. 27%; p-value < 0.001). There was no statistically significant difference in preference for white and yellow maize by primary school children. Secondary school and adult subjects preferred white maize to yellow maize. Focus group discussions confirmed the preference for white maize by the adults. Conclusion: The study findings suggest that yellow, provitamin A-biofortified maize has the potential to succeed as a new strategy of dealing with the serious problem of vitamin A deficiency, especially among children of preschool age. However, in older groups, this strategy is unlikely to be successful, unless other strategies are implemented, including intensive nutrition education programmes on the nutritional benefits of the maize, targeting the market price at which yellow maize is sold, increasing its availability in local grocery stores, and improving its sensory properties through breeding.

Provitamin A carotenoids in biofortified maize and their retention during processing and preparation of South African maize foods

Provitamin A-biofortified maize may contribute to alleviating vitamin A deficiency (VAD), in developing countries. However, processing the maize into food products may reduce its provitamin A content. The aims of this study were to determine the composition of provitamin A carotenoids in biofortified maize varieties as well as to assess their retention during processing of popular maize foods consumed in KwaZulu-Natal, South Africa. The non-provitamin A carotenoid, zeaxanthin and the provitamin A carotenoids, β-cryptoxanthin, and trans and cis isomers of β-carotene, and other unidentified trans and cis isomers of β-carotene were detected in varying concentrations in the maize. Milling provitamin A-biofortified maize into mealie meal resulted in a higher retention of carotenoids compared to milling into samp. The highest retention of provitamin A carotenoids was observed in cooked phutu and cooked samp, whilst cooking into thin porridge resulted in the lowest retention of provitamin A carotenoids. In phutu, 96.6 ± 20.3% β-cryptoxanthin and 95.5 ± 13.6% of the β-carotene were retained after cooking. In samp, 91.9 ± 12.0% β-cryptoxanthin and 100.1 ± 8.8% β-carotene; and in thin porridge, 65.8 ± 4.6% β-cryptoxanthin and 74.7 ± 3.0% β-carotene were retained after cooking. This study demonstrates that provitamin A retention in maize is affected by the cooking method (and hence cooked food form) and therefore cooking methods that result in a good retention of provitamin A need to be identified and recommended.

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.

Acceptance of a complementary food prepared with yellow, provitamin A-biofortified maize by black caregivers in rural KwaZulu-Natal

Abstract Objectives: The objective was to assess the sensory acceptability and consumer perceptions of soft porridge made with yellow, provitamin A-biofortified maize by black African female infant caregivers from rural KwaZulu-Natal. Design: This was a cross-sectional study. Setting: The study was conducted at Edendale Hospital, located in the uMgungundlovu District, KwaZulu-Natal province. The hospital serves a high proportion of people from rural areas in this district. Subjects: Sixty black African female infant caregivers participated in the study. Outcome measures: The sensory acceptability of soft porridge made from two varieties of provitamin-A biofortified maize and one variety of white maize were evaluated by black African female infant caregivers (n = 60) using a five-point facial hedonic scale. Some of the subjects (n = 21) participated in focus group discussions to assess consumer perceptions. Results: There was no significant difference in the sensory acceptability of the biofortified maize porridge and the white maize porridge, irrespective of caregiver age (p-value > 0.05). The caregivers expressed a willingness to give their infants porridge made with provitamin A-biofortified maize if it was more affordable, readily available and beneficial to health. Conclusion: The biofortified maize soft porridge was found to be as acceptable as the white maize soft porridge to black African female infant caregivers from rural KwaZulu-Natal. Provitamin A-biofortified maize has the potential to be used as a complementary food item that would contribute to the alleviation of vitamin A deficiency.

Effects of amaranth addition on the pro-vitamin A content, and physical and antioxidant properties of extruded pro-vitamin A-biofortified maize snacks

BACKGROUND Pro-vitamin A-biofortified maize snacks with added leafy vegetable may have a potential as nutritious and health-promoting products, especially in addressing vitamin A deficiency, which is prevalent in developing regions. The objective of the study was to determine the effects of adding amaranth leaf powder on the physical, antioxidant properties and pro-vitamin A content of extruded pro-vitamin A-biofortified maize snacks. Extruded snacks were processed using four pro-vitamin A-biofortified maize varieties that were composited with amaranth leaf powder at 0%, 1% and 3% (w/w) substitution levels. RESULTS At higher amaranth concentration, the expansion ratio of the snacks decreased, while their hardness increased by as much as 93%. The physical quality of the snacks may therefore need improvement. As amaranth was increased, the phenolic content and antioxidant activity of the snacks increased as well as the pro-vitamin A content. CONCLUSION Pro-vitamin A-biofortified maize with added amaranth has a potential for use in nutritious and healthy extruded snacks. There are limited studies reporting on processing pro-vitamin A maize with complementary plant foods, which is common with white maize in southern Africa; thus the current study serves as a baseline.

Effect of Amaranth addition on the nutritional composition and consumer acceptability of extruded provitamin A-biofortified maize snacks

The objective of this study was to determine the effect of adding Amaranth leaf powder on the nutrient content and consumer acceptability of extruded provitamin A-biofortified (PVA) maize snacks. Flours of four varieties of PVA maize were composited with Amaranth leaf powder at 0, 1 and 3% (w/w) substitution of, respectively, and extruded into snacks. The ash content of the snacks increased from 0.53 g/100 g-0.58 g/100 g to 0.650 g/100g-89 g/100 g and protein content increased from 9.12 g/100 g-10.94 g/100 g when Amaranth was increased from 0% to 3%. Similarly, lysine content increased from 0.10 g/100 g to 0.17 g/100 g, whilst methionine increased from 0.14 g/100 g to 0.19 g/100 g. The provitamin A content of the snacks ranged from 1.29 µg/g to 1.40 µg/g at 0% Amaranth and 1.54 µg/g to 1.78 µg/g at 3% Amaranth. The acceptability of the snacks decreased with increasing Amaranth concentration, only a very small proportion (2-8%) of the panel liked the snacks extremely. PVA maize with added Amaranth leaf powder has a potential for use in nutritious and healthy extruded snacks, but the consumer acceptability of the snacks should be improved.

Influence of biofortification with provitamin A on protein, selected micronutrient composition and grain quality of maize

Provitamin A-biofortified maize is currently being evaluated for use in the alleviation of vitamin A deficiency. Apart from the differences in provitamin A content, the nutritional composition of provitamin A-biofortified maize compared to white maize is hardly known. This study aimed to evaluate the protein and selected micronutrient composition of biofortified maize varieties and the quality of their grains. A total of 32 provitamin A-biofortified maize varieties was analysed for their starch, fat, protein and mineral content. The milling and storage quality of the biofortified maize grains were also assessed. When compared with the white maize variety, the biofortified varieties were higher in starch, fat and protein, but were lower in iron. The biofortified maize varieties were better sources of most of the essential amino acids relative to the white variety, but, similar to the white maize, they were deficient in histidine and lysine. Overall, the quality of the grains of the biofortified maize varieties was superior to that of the white maize grain, although, the biofortified grains were more susceptible to fungal invasion. This study indicates that, in terms of the nutrients assessed, provitamin A-biofortified maize is generally superior to white maize, except for minerals. Keywords: Biofortification, provitamin A, protein, micronutrient composition, maize. African Journal of Biotechnology Vol. 12(34), pp. 5285-5293

Acceptability of a moringa-added complementary soft porridge to caregivers in Hammanskraal, Gauteng province and Lebowakgomo, Limpopo province, South Africa

Objectives: This study determined caregivers’ (mothers’) acceptability and perceptions of a soft, white maize porridge (traditional complementary food (TCF)) that was modified by substituting maize meal with Moringa oleifera Lam. leaf powder at different levels, 1%, 2% and 3% weight for weight (w/w). Design: A cross-sectional study was conducted. Setting: The study was conducted in Stinkwater, Hammanskraal, Gauteng province (25° 23’ 59.99” S: 28° 16’ 60.00” E) and Ga-Mphahlele village, Lebowakgomo, Limpopo province (24°18’0.83”S: 29°32’33.61”E), South Africa. Subjects: Sixty mothers were sampled, separately, from Hammanskraal and Lebowakgomo communities. Outcome measures: The sensory acceptability of the complementary soft porridges was evaluated by caregivers from Hammanskraal and Lebowakgomo communities using a five-point facial hedonic scale (n = 60 per study area). A series of three focus-group discussions were conducted per study area (n = 12 persons per group) to assess caregivers’ perceptions on the inclusion of moringa in complementary foods. Results: Sensory evaluation results showed that the acceptability of the two traditional complementary foods decreased as the level of moringa leaf powder increased. Caregivers indicated in the focus-group discussions that moringa-based soft porridges had a bitter taste, which would not be suitable for children. Only the Lebowakgomo modified traditional complementary food (MTCF) containing 1% of moringa was rated similar in overall acceptability to the corresponding TCF (control). Nevertheless, all caregivers expressed willingness to use moringa in complementary foods provided they would be trained on how to process it. Conclusions: Varying product formulation and processing methods may contribute to increased acceptability of moringa-based foods. Overall, moringa appears to have the potential for use in complementary foods.

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.

An Assessment of the Food and Nutrition Security Status of Weaned 7–12 Months Old Children in Rural and Peri-Urban Communities of Gauteng and Limpopo Provinces, South Africa

This study assessed the food and nutrition security status of children receiving complementary food in rural and peri-urban communities. A group of 106 mothers from Lebowakgomo village and Hammanskraal Township, respectively, participated in the survey. Additionally, six focus group discussions were conducted per study area to assess the mothers’ perceptions about children’s food access. The Children’s Food Insecurity Access Scale (CFIAS) was used to assess the food security status (access) of the children. The Individual Dietary Diversity Score (IDDS) together with the unquantified food consumption frequency survey were used as a proxy measure of the nutritional quality of the children’s diets. The age and weight of the children obtained from the children’s clinic health cards were used to calculate Weight-for-Age Z scores (WAZ) in order to determine the prevalence of underweight children. The findings showed that a large percentage of children were severely food-insecure, 87% and 78%, in rural and peri-urban areas, respectively. Additionally, Lebowakgomo children (23.6%) and Hammanskraal children (17.9%) were severely underweight. Overall, children’s diets in both study areas was characterized by nutrient-deficient complementary foods. Cheaper foods with a longer stomach-filling effect such as white maize meal and sugar were the most commonly purchased and used. Hence, the children consumed very limited amounts of foods rich in proteins, minerals, and vitamins, which significantly increased the risk of their being malnourished.