Nutritional and phenotypical characterization of two South African maize (Zea mays L) varieties sampled in the Qwa-Qwa region

Zea mays L represents one of the main source of energy in the diet in many African countries, especially in the sub-Saharan regions. White maize varieties, characterized by the lack of carotenoids, are usually widely preferred in Africa for human consumption, and this contributes to the occurrence of Vitamin A deficiency; yellow varieties, often derived from commercial hybrids, are usually destined for animal feeding. In this study we characterized from the phenotypical and nutritional points of view one white and one yellow South African landrace maize cultivar obtained directly from the farmers in the rural region of Qwa-Qwa (Free State Province). Calorific value, oil, protein, starch, minerals, flavonoids and carotenoids content were determined, together with free and phytic phosphorus (P). Both of the varieties showed lower protein and Fe content in comparison to the ones used as control, and the yellow one also had a low content of Zn. The white variety was characterized by a higher free P content but also by a very low level of carotenoids. Our data show that there are no nutritional reasons to prefer the white variety for human consumption, with the exception of the large size of the seeds, which make them particularly adapted for milling; hence the nutritional value of these varieties, and in particular of the white one, should be improved (protein, Fe and carotenoids), contributing in this way to tackle the problem of malnutrition in South African rural areas

Exploring the prevalence of multiple forms of malnutrition in children 6–18 years living in the Eastern Cape, South Africa

Background: The existence of multiple forms of malnutrition is a growing problem in developing countries. Children living in the Eastern Cape have a relatively high prevalence of cardiovascular disease (CVD) risk factors and food insecurity, suggesting the possibility of the several coexisting forms of malnutrition. Due to the negative long-term consequences of undernutrition, overnutrition and, to a greater extent, a combination of both, it is important for this issue to be identified early in children and addressed. Aim: This study was undertaken to investigate the prevalence of the different forms of malnutrition in children living in the Eastern Cape province. Methods: Secondary analysis of a cross-sectional sample of 237 school-aged children, aged 6–18 years, in the Eastern Cape province of South Africa was conducted. The variables included in the analysis were the demographic data, anthropometric data and biochemical data, specifically blood profiles related to micronutrient deficiencies and CVD risk factors. Fisher’s exact test was used to compare the prevalence rates of several coexisting forms of malnutrition in the children. All data analysis was conducted in R version 4.0.3 and statistical significance was set at 0.05. Results: In children with overweight/obesity, 13.6% had a micronutrient deficiency, while 37.71% of the children within the normal weight range had coexisting micronutrient deficiencies and CVD risk factors. The prevalence of folate deficiency was 73.0%, iron deficiency 6.3%, and hyperglycaemia was at 10.6%. Fisher’s exact test was used to compare the prevalence rates between genders and no statistically significant differences were observed. Conclusion: Further research is needed to understand the relatively high prevalence of CVD risk factors in these children within the normal weight range and to investigate how dietary intake contributes to the overall double burden of malnutrition in children

Home-prepared soymilk: Potential to alleviate protein-energy malnutrition in low-income rural communities in South Africa?

Research findings reported pronounced protein and some energy shortfalls for school-aged children and female caregivers in rural communities in Qwa-Qwa, South Africa. The household gardening project was expanded to include soy cultivation. Subsequently, a process was developed for home-preparation of soymilk to support macronutrient consumption. The limited explorative experimental approach included chemical analysis for total protein (Kjeldahl digestion, spectrophotometric determination), total carbohydrate (Anthone method) and total lipid content (extraction, Gravimetric method, separation). Total energy content was calculated. All results were benchmarked against equivalents. Duplicate analysis of samples, respectively prepared from 1:2 (n = 6) and 1:4 (n = 4) volume ratios of rehydrated minced soybeans : water for cooking of soy mash, indicated statistically-significant differences for reported nutrients (p ≤ 0.05). Comparison between sourced commercial soymilk products for drinking indicated no statistical differences (p > 0.05). Although statistically-significant shortfalls were indicated for nearly all such values for home-prepared soymilk (1:4 ratio) against industrial ‘SoyCow’ soymilk and values reported in the South African database for standardised nutrient composition of food (p ≤ 0.05), a much-needed contribution will be made to protein (and energy) intake through consumption of the product. More efficient extraction (possibly double mincing of rehydrated soybeans and more efficient pressing of cooked soy mash) should be explored, followed by an intervention study to evaluate the impact of daily consumption of home-prepared soymilk on the nutritional status of children in low-income communities. The development of recipes to promote the inclusion of undissolved fibre from the soymilk extraction process (okara) in dishes prepared at household level, such as bread, is recommended. Navorsing het beduidende proteïen en minder ernstige energie te korte uitgewys by skoolkinders en vroulike versorgers in plattelandse gemeenskappe in Kwa-Kwa. Die huishoudelike tuinbouprojek is uitgebrei om soja-verbouing in te sluit en ’n proses is ontwikkel vir die tuisbereiding van sojamelk om makronutriënt inname te bevorder. Die beperkte eksperimentele benadering het chemiese analise vir totale proteïen (Kjeldahlvertering, spektro-fotometriese bepaling), totale koolhidraat (Anthonemetode) en totale lipied inhoud (ekstraksie, Gravimetriese metode, skeiding) ingesluit. Totale energie is bereken en alle resultate is met ekwivalente vergelyk. Duplikaatanalise van sojamelkmonsters, onderskeidelik berei van 1:2 (n = 6) en 1:4 (n = 4) volume verhoudings van gehidreerde gemaalde sojabone : water vir die kook van die sojapulp, het statisties-beduidende verskille uitgewys (p ≤ 0.05). Geen statisties-beduidende verskille is gevind in die makronutriëntwaardes van kommersiële sojamelkprodukte wat gedrink kan word nie (p > 0.05). Alhoewel statisties-beduidende tekorte vir bykans alle soortgelyke waardes van tuisbereide sojamelk (1:4) teenoor die industrieel bereide ‘SoyCow’ produk en waardes gerapporteer in die Suid Afrikaanse databasis vir gestandardiseerde nutriëntsamestelling van voedsel (p ≤ 0.05) waargeneem is, sal inname van die tuisbereide produk tog ’n belangrike bydrae tot proteïen (en energie) inname kan lewer. Die effektiwiteit van ’n verbeterde nutriëntekstraksie, byvoorbeeld deur ‘n dubbel-maalproses en meer effektiewe pers van die gekookte sojapulp, moet ondersoek word. ’n Intervensiestudie om die effek van daaglikse sojamelk inname op die voedingstatus van kinders in lae-inkomste bemeenskappe te meet, word aanbeveel. Verder word aanbeveel dat resepte ontwikkel word om die onopgeloste vesel wat oorbly na die melkmaak proses (okara) in huishoudelike geregte in te sluit, byvoorbeeld in die bereiding van brood

Prevalence of zinc deficiency among primary school children in a poor peri-urban informal settlement in South-Africa

This cross-sectional study assessed the risk of zinc deficiency in randomly selected children, aged between 7 and 11 years, living in a poor, peri-urban informal settlement in South Africa. Dietary intake of 149 respondents was evaluated by 24-hour recall and quantitative food frequency questionnaires. Anthropometric and biochemical indices of a subset of 113 were determined. Descriptive statistics, analysis of variance and Pearson correlations were computed using the Statistical Package for Social Sciences, version 14.0. Anthropometric data were analysed using the World Health Organization Anthro plus version 1.0.2 statistical software. Dietary data were analysed with FoodFinder® version 3. The mean age of the children was 9.0±1.1 years. Few zinc-rich sources appeared in the diet that was predominantly plant-based. Mean dietary zinc intake was 4.6±2.2 mg/day. The mean value of serum zinc was 66.4±21.5 µg/dL, with 46% of the children having values less than the 70 µg/dL cut-off. The findings indicate a high risk of zinc deficiency and suboptimal zinc status for the majority of this study population of children, possibly as a result of low consumption of food sources with high bioavailability of zinc, which invariably is a direct consequence of poverty and food insecurity.Die doel van hierdie dwarsdeursnitstudie was die bepaling van die risiko van ’n sinktekort in ’n ewekansige steekproef van 7 tot 11 jaar-oue kinders, woonagtig in ’n arm, voorstedelike informele woonbuurt in Suid Afrika. Dieetinnames van 149 respondente is geëvalueer deur 24-uur herroep en kwantitatiewe voedselfrekwensie vraelyste. Antropometriese en biochemiese indikatore van ’n kleiner steekproef van 113 is ook bepaal. Beskrywende statistiek, analise van variansie en Pearsonkorrelasies is bepaal deur die Statistical Package for Social Sciences, uitgawe 14.0. Antropometriese data is geanaliseer deur die statistiese program, Anthro plus, uitgawe 1.0.2, van die Wêreld Gesondheid Organisasie. Dieetdata is met behulp van FoodFinder® uitgawe 3 geanaliseer. Die gemiddelde ouderdom van die kinders was 9.0±1.1 jaar. Min sinkryke voedselbronne is in die hoofsaaklik plantryke dieet waargeneem. Die gemiddelde sinkinname was 4.6±2.2 mg/dag en die gemiddelde serumsinkwaarde was 66.4±21.5 µg/dL, met 46% van die kinders se waardes onder die 70 µg/dL afsnypunt. Die bevindings dui op ’n hoë risiko vir sinktekort en suboptimale sinkstatus vir die meerderheid van hierdie kinders, moontlik as gevolg van die swak inname van voedselbronne met hoë biobeskikbare sink, wat gewoonlik ’n direkte gevolg van armoede en huishoudelike voedsel insekuriteit i