Antinutrients and metabolomic compounds of Bambara groundnut (Vigna subterranean) as affected by traditional processing by smallholder farmers.

Bambara groundnut (BG) (Vigna subterranean) is an underutilized, indigenous crop in South Africa that has nutritional and associated health benefits. Decreasing the antinutrients in food sources can potentially increase the digestibility of proteins and mineral absorption. To determine the effect of traditional processing (cooking) on the antinutrient content and metabolome of this crop, BG was sampled from 12 rural farms in three districts of the Mpumalanga province, South Africa. The four main colors that were identified (cream, orange, brown, and purple) were pooled together according to the district they were obtained from. One-half of each color sample obtained from each of the three districts was dehulled, color sorted, milled, and subjected to subsequent antinutrient and metabolome analyses, while the other half was cooked, air-dried, and milled prior to analyses. Samples were analyzed for phytate and tannins (antinutrients) by hydrochloric acid extraction methods as well as metabolome constituents by ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). Phytate, tannins, as well as other metabolomic constituents, namely, catechin, epicatechin, procyanidin, as well as citric acid, were identified in all raw and cooked BG samples. The cooking process resulted in a significant decrease (p < 0.05) in the phytate and tannin content as well as an increase in the health-associated phenolic compounds.

Monitoring the quality of honey: South African case study.

The popularity of honey as a high-valued commodity is growing and consequently, honey adulteration is on the rise affecting the honey quality. The quality of the honey on the South African market was evaluated using the Agricultural Product Standards Act, 1990 as assessment tool. Various physico-chemical characteristics were tested which indicated compliance of >80% for all honey samples. A canonical variate analysis using 95% confidence regions indicates significant differences between the quality of local and imported honey with total acid, sucrose and ash as the parameters mostly distinguishing between the groups. Honey produced from agricultural crops differed significantly from all other forage types. The parameters that mostly distinguished between forage types were Lund, hydroxy-methyl-furfural and ash content. Even though honey sold on the South African market is generally in accordance with national and international standards, an overall declining trend in quality was observed and it should be continuously monitored.

Importance and use of reliable food composition data generation by nutrition/dietetic professionals towards solving Africa's nutrition problem: constraints and the role of FAO/INFOODS/AFROFOODS and other stakeholders in future initiatives.

Despite the rich biodiversity of the African continent and the tremendous progress so far made in food production, Africa is still struggling with the problems of food insecurity, hunger and malnutrition. To combat these problems, the production and consumption of nutritious and safe foods need to be promoted. This cannot be achieved without reliable data on the quantity and quality of nutrients and other components provided through these foods. Food composition data (FCD) are compiled as food composition tables (FCT) or food composition databases (FCDB). These are subsequently used for a variety of purposes, ranging from clinical practice, research, public health/education, food industry to planning and policy, as well as nutrition monitoring and surveillance. To perform these functions effectively, the importance of reliable FCT/FCDB cannot be overemphasised. Poor quality FCT/FCDB have serious consequences on the health of the population, and provide skew evidence towards developing nutrition and health-related policies. The present paper reviews different methods to generate FCT/FCDB, their importance and use in assisting nutrition/dietetic professionals in solving Africa's nutrition problems; current status of FCT/FCDB generation, compilation and dissemination in Africa, constraint to their use by professionals and the role of FAO/INFOODS/AFROFOODS and other stakeholders towards improvement and future initiatives. The information provided will create awareness on the need for up-to-date and high-quality FCT/FCDB and facilitate the identification of data gaps and prioritisation of future efforts in FCD generation, compilation and dissemination in Africa and subsequent strategies for the alleviation of the food and nutrition problems in Africa.

Using regulation to limit salt intake and prevent non-communicable diseases: lessons from South Africa's experience.

OBJECTIVE: To analyse the policy process for the South African regulation setting upper limits for salt in thirteen commonly consumed food categories, to inform future policy action for prevention of non-communicable diseases. DESIGN: Semi-structured interviews (n 10) were conducted with key stakeholders from government, academia, non-governmental organisations and the food industry. Interviewees were asked about the content, context, process and actors involved in developing the regulation. Data were analysed according to Walt and Gilson's health policy analysis triangle. SETTING: South Africa. PARTICIPANTS: Key actors and stakeholders in the policy process to develop the salt regulation. RESULTS: The regulation was a response to research establishing the effectiveness of food supply interventions and to a shared perception that government regulation was the quickest way to address the problem of salt overconsumption. While the regulations were developed through a consultative process, food industry stakeholders perceived the consultation as inadequate. Implementation is currently underway, supported by a health promotion programme. Monitoring and enforcement were identified as the most likely challenges due to capacity constraints. CONCLUSIONS: Comprehensive mandatory salt limits are an innovative approach to food reformulation. Factors that enabled regulation included robust scientific evidence, strong political and bureaucratic leadership, and the pragmatic use of existing regulatory instruments. The main challenges identified were disagreement over the appropriate nature and extent of food industry participation, and monitoring and enforcement challenges due to capacity constraints.

The contribution of processed pork meat products to total salt intake in the diet.

Consumption of processed meats is reported to be the second largest contributor to total dietary sodium intake. This study aims to describe the contribution of commonly consumed processed pork products to total salt intake. A large variation was found in the sodium content between similar products. Sodium content (mg/100g) for bacon ranged from 558 to 1570, russians from 762 to 1403, viennas from 480 to 1340 and ham from 696 to 1360 respectively. When converting sodium content from 100g to serving size, different products contributed the most sodium to the diet. A serving size of brawn (125g uncooked) will contribute on average 983mg sodium to total sodium intake. Pork bangers will contribute the lowest amount of sodium (∼400mg) to the diet (∼4% of RDI). Reported daily intake are smaller than indicated serving sizes and the contribution of processed meat to sodium intake can be predicted to be lesser than expected.

The important role of food composition in policies and programmes for better public health: A South African case study.

Most governments have committed to the set of Sustainable Development Goals established by the United Nations (UN) to be achieved by 2030. Subsequently the governments have drafted, or are in process of drafting, policies and programmes which aim to answer to these global requests. South Africa provides a unique case study: despite economic growth, undernutrition has not improved when compared to other industrialised nations, while at the same time, diet-related non-communicable diseases and obesity have exponentially increased. Access to healthy food is a constitutional right of all South Africans, and towards increasing food security and improving population health, various policies, programmes and regulations have been developed and implemented by the government to rectify the situation. The paper presents an overview of food composition within these public health policies, programmes and regulations and unpacks the important role of accurate food composition data.

Total and haem iron content lean meat cuts and the contribution to the diet.

This study provides data on the total and haem iron contents in raw lean beef, chicken, lamb and pork meat samples. Total iron, expressed as mg/100g edible portion on fresh weight basis in raw lean beef (A-age), lamb, pork and chicken average 1.58, 1.64, 0.81 and 0.78, respectively. The haem iron content in beef (A-age), lamb, pork and chicken are 77%, 81%, 88% and 74% respectively of total iron. This has important dietary implications in calculating haem iron fractions of meat as this is higher than the common value used in the Monsen equation.

Effect of animal age and trimming practices on the physical composition of Bonsmara beef.

Increased economic incentive for producing young and leaner carcasses, as well as demand for lean meat from progressively health conscious consumers, are considered drivers for change in carcass composition over time. Furthermore, many retailers trim visible fat from meat to various degrees and consumers increasingly remove visible fat from meat prior to, or after, cooking. The objective of this study was to determine the composition of South African Bonsmara beef from four age groups from different production systems, as well as to extrapolate the effect of fat trimming on physical composition. Fat content of marketable beef has decreased notably since the 1930s, and beef from the South African Bonsmara breed contains less than 10g lipid per 100g after trimming of subcutaneous fat, irrespective of age. Removal of all visible fat reduces the lipid content to less than 5g per 100g, comparing favourably with other lean animal products.

A Review of Dietary Surveys in the Adult South African Population from 2000 to 2015.

One serious concern of health policymakers in South Africa is the fact that there is no national data on the dietary intake of adult South Africans. The only national dietary study was done in children in 1999. Hence, it becomes difficult to plan intervention and strategies to combat malnutrition without national data on adults. The current review consequently assessed all dietary studies in adults from 2000 to June 2015 in an attempt to portray typical adult dietary intakes and to assess possible dietary deficiencies. Notable findings were that, in South Africa micronutrient deficiencies are still highly prevalent and energy intakes varied between very low intakes in informal settlements to very high intakes in urban centers. The most commonly deficient food groups observed are fruit and vegetables, and dairy. This has been attributed to high prices and lack of availability of these food groups in poorer urban areas and townships. In rural areas, access to healthy foods also remains a problem. A national nutrition monitoring system is recommended in order to identify dietary deficiencies in specific population groups.

Capacity building in food composition for Africa.

Capacity building in food and nutrition involves more than formal training and individual development. Such a process is long term and continues, requiring lasting mentorship, coaching and leadership development, including individual commitment to continued self-development. It expands to include the development of knowledge and skills of an individual within his/her organizational or institutional arrangements, and requires buy-in and support from his/her institution or organization, as well as other funding bodies involved in agriculture and health. It needs to be supported by government and be part of the regional and international agenda for agriculture and health. Under the auspices of International Network of Food Data Systems (INFOODS), an African Network of Food Data Systems (AFROFOODS) was established in September 1994, and a number of training courses, educational and scientific publications, posters, presentations and visits were hosted, organized and delivered with the aim to build enthusiasm, long term commitment and capacity in food composition within the AFROFOODS region. Formal training and human resource development were the major focus to take food composition forward in Africa. Significant progress was made in food composition activities, but constraints including lack of organizational and institutional commitment and financial support are straining the pace of progress.

Effect of different maize meal diets on growth and vitamin A: case-study on chickens.

South Africa embarked on mandatory vitamin and mineral fortification of wheat flour and maize meal in 2003 as part of a multi-faceted approach to alleviate malnutrition. However, it was reported, in 2008, that vitamin A deficiency increased despite the mandatory fortification programme. This motivates an investigation into the absorption of vitamin A as fortificant in the maize meal. Relative absorption, in chickens as the biological model, was determined by evaluating growth and vitamin A status. The weight, cumulative feed intake and liver retinol stores of chickens on different diets were measured over a 6week period. The fortified white maize meal diet was able to maintain the vitamin A status of the chickens. Poor absorption of the fortificant vitamin A is therefore not a constraint in combating vitamin A deficiency. It is in therefore also important to focus on the level of fortification delivered when consumed as a traditional prepared dish. In the traditional diet, maize porridge is often consumed with only a relish. The total fat content of the traditional meal is very low, lacking absorption enhancers.

Total nitrogen vs. amino-acid profile as indicator of protein content of beef.

In most cited food composition studies and tables, the proximate system measures protein as total nitrogen (N) (determined by Kjeldahl or Dumas method) multiplied by a specific factor. A factor of 6.25 is used for determining total protein from total N (Jones, Munsey, & Walker, 1942). Although more expensive, it is considered more accurate to base protein content of foods on amino acid data (Greenfield & Southgate, 2003). A study on the nutrient composition of beef analysed the full amino-acid profile of fifteen retail cuts from three age groups and six fat codes, as well as determined total nitrogen content to determine proximate protein composition. For all cuts, the correlation coefficient of total amino acids to protein (N×6.25) was 0.635. This indicates a poor correlation for predicting actual protein content (as determined by total amino acid count), based on the nitrogen factor of 6.25. On average, the sum of amino acids per cut amounted to 91% of total determined protein (N×6.25) for the same cut.

A comparison of the eating quality of selected potato cultivars from two potato production regions in South Africa.

BACKGROUND: Limited scientific information is available on the eating quality of potato cultivars in South Africa. This study aimed to determine, describe and compare the eating quality of three potato cultivars from two production regions (dry land and irrigated land) in South Africa, through sensory and physical evaluation. Sensory descriptors were identified for the sensory attributes and a lexicon was developed. A category scale was used to rate the sensory attributes and physical measurements of specific gravity, shear force resistance and scanning electron microscopy were performed. RESULTS: It became evident that both sensory evaluation and physical measurements need to be performed in order to determine the eating quality of potato cultivars, as one evaluation supports the other. A partial least squares regression modelling method was used to relate the sensory attributes and physical measurements. The intensity of the sensory attributes of the specific cultivars varied between the two production regions. CONCLUSION: The eating quality of potatoes obtained from two production regions differed from another due to climatic conditions and other production characteristics that exist (dry land vs. irrigation). The study confirms the valuable contribution of determining the eating quality of potato cultivars.

Dietary protein quality and malnutrition in Africa.

The WHO (2007) Technical Report on protein and amino acid requirements in human nutrition states that the best estimate for a population average requirement is 105 mg nitrogen/kg body weight per day, or 0·66 g protein/kg body weight per day. In many developing countries protein intake falls significantly short of these values. Apart from protein quantity, protein quality including bioavailability and digestibility, from different food sources, are currently on the global agenda. The 1st International Symposium on Dietary Protein for Human Health held in Auckland, in March 2011, and the consecutive Food and Agricultural Organization of the United Nations (FAO) Expert Consultation on Dietary Protein Quality, both highlighted the importance of assessing the quality of protein from different food sources through determination of amino acid content. Throughout the developed world, animal products and cereals are the two most important sources of protein; in developing countries this order is reversed. In low income countries only 3 % of total dietary energy, as an indicator of diet composition, is derived from meat and offal, 11 % from roots and tubers and 6 % from pulses, nuts and oilseeds. The remainder of the dietary energy is mainly derived from cereal-based staple food. Although the production of livestock has increased in developing countries, the consumption of protein in these countries with people consuming the most limited amounts of protein are continually decreasing. Undernutrition, including insufficient consumption of protein, remains a persistent problem in the developing world, and although many diets within these developing countries are deficient in the quantity of protein compared to recommendations, the quality of the protein also strongly comes into focus.

Food-coping strategy index applied to a community of farm-worker households in South Africa.

BACKGROUND: In South Africa, households living in informal urban settlements, in rural areas, and on commercial farms experience various levels of dietary variety, food intake, and household hunger. Low incomes, poor food production and availability, and low spending power characterize these households. Households employ various food-coping strategies to alleviate food stress or poor food availability. OBJECTIVE: To apply an existing food-coping strategy (FCS) index to assess household hunger and its usefulness in identifying the level of food stress and the patterns of food coping in farm-worker households. METHODS: A cross-sectional survey was conducted. Data were gathered from women (18 to 57 years of age) responsible for food provision in a small farm-worker community in Fouriesburg, South Africa. A structured food-coping questionnaire and a standardized FCS index were used to gather data. RESULTS: The two most common FCS used were relying on cheaper food (chicken feet, diluted soya-mince soup) or less preferred food (meat bones) and employing food-seeking strategies (gathering wild foods), followed by consumption of seed stock (maize) and reduced portion sizes (protein foods and side dishes), resulting in starch-based diets of poor variety. Seasonal strategies varied according to the level of food stress experienced. Patterns of food coping were identified. CONCLUSIONS: Negative FCS (limiting food choices, only consuming starchy staples) may cause poor health status. The FCS index was effectively used to assess farm-worker household food-coping behavior (early, clear signals of the level of food distress). These results could be used to allocate appropriate food aid (type of food) and to design nutrition education programs focused on positive FCS (food gathering or bartering) in a particular community to prevent suboptimal nutritional status.