H.C. Schonfeldt
University of Pretoria
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Meat Science | 1993
H.C. Schonfeldt; R.T. Naudé; W. Bok; S.M. van Heerden; L. Sowden; E. Boshoff
Significant differences exist between the quality characteristics of meat obtained from 27 sheep, Angora and Boer goat carcases, when compared. Sheep meat showed greater drip loss than goat meat and was more juicy than that of Angora and Boer goat meat. In general, Angora goat meat was found to be more juicy than Boer goat meat. Drip loss increased significantly with increased animal age. Meat of younger animals (no permanent incisors) was more juicy (initial and sustained) than that of older animals (7-8 permanent incisors). This was irrespective of whether it was obtained from sheep, Angora or Boer goats and was confirmed by the expressible moisture measurements. Higher drip, evaporation and total cooking loss were reported when carcases had increased fat content. With increasing fatness of carcases, the juiciness of the cooked cuts decreased and the expressible moisture content of the meat increased.
Meat Science | 1993
H.C. Schonfeldt; R.T. Naudé; W. Bok; S.M. van Heerden; R. Smit; E. Boshoff
The quality characteristics of 27 Angora goats, Boer goats and sheep carcases were compared. Significant differences exist between the quality characteristics of sheep meat and Angora or Boer goat meat. Sheep meat has a more intense aroma, it is more tender, contains less fibrous tissue residue and the species flavour is more pronounced (typical) than that of Angora and Boer goat meat. In general, goat meat was found to be significantly different to sheep meat, the Angora to a lesser extent, however, than the Boer goat. This study confirms the fact that the meat of younger animals is more tender, contains less fibrous tissue residue and the species flavour is less typical than that of older animals. This was irrespective of whether it was obtained from sheep, Angora or Boer goat. With increasing fatness of carcases, the tenderness and species flavour of the cooked cuts increased significantly.
British Journal of Nutrition | 2012
H.C. Schonfeldt; Nicolette Gibson Hall
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 Chemistry | 2013
Nicolette Gibson Hall; H.C. Schonfeldt
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.
Food and Nutrition Bulletin | 2008
Rozanne Kruger; H.C. Schonfeldt; Johanna Hendriena Owen
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.
The South African journal of clinical nutrition | 2011
Ingrid Vivienne Van Heerden; H.C. Schonfeldt
Abstract Generally, South African researchers working in the fields of nutrition and dietetics collect food intake data as a first step towards determining the nutritional status of various populations. However, on publication, the majority of the results obtained from these studies are expressed in terms of nutrient intake, whereas food intake data are either not included, or are presented in non-uniform formats. Subsequently, other researchers who wish to determine what foods South Africans are eating are not able to access food intake data from existing studies. For example, if the Food-Based Dietary Guidelines (FBDG), which are expressly based on food, and not nutrient intakes, are to be revised regularly as stipulated by the World Health Organization (WHO), very little additional food intake data from the decade following publication of the first FBDG in 2001 would be available for adult South Africans. It is probable that the consumption of certain foods may have increased because of urbanisation and Westernisation of large sectors of the population. Conversely, economic factors, including the present recession, household food insecurity and poor food choices, may have reduced the intake of nutrient-dense foods in the past decade. The present review describes the disparity in reporting of food intake data, and deficiencies in making data that are available in electronic storage systems accessible to researchers working in the fields of public health nutrition, food production and utilisation, community nutrition and education. The creation of a working committee to make food intake data more accessible is proposed.
Development Southern Africa | 2011
Teclah P Khumalo; H.C. Schonfeldt; Hester Vermeulen
This study examined the acceptability and perceptions of traditionally prepared maize meal porridge, cooked from commercial roller-mill white maize meal and hammer-mill white and yellow maize meal (with and without fibre), among female Tsonga consumers in Giyani in Limpopo Province, South Africa. The study used sensory evaluation tests, followed by focus group discussions to gather supportive information about consumer attitudes, perceptions and practices regarding the consumption of maize meal porridge prepared from these maize meal types. Giyani consumers preferred commercial roller-mill white sifted fortified and white super-fortified maize meal, but, contrary to popular belief, were also willing to accept hammer-mill yellow maize meal, mainly for its nutritional value.
Food Chemistry | 2013
Beulah Pretorius; H.C. Schonfeldt
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.
Development Southern Africa | 2005
Anne Bichard; Sandrine Dury; H.C. Schonfeldt; Tshidi Moroka; Faith Motau; Nicolas Bricas
This study of urban residents of Polokwane, the capital of the Limpopo province in South Africa, was designed to describe how, where, when and by whom sorghum and millet are consumed; how the subjects of the study perceived these grains; to what extent the produce of small-scale producers was considered acceptable; and to gauge their potential demand for products derived from indigenous cereals. Qualitative data were collected using individual interviews and focus-group sessions. The findings suggest that sorghum, which is easily purchasable in town, is widely consumed, mainly as soft porridge, but also as thick porridge, fermented porridge and sorghum beer. The age of consumers, the closeness of their links with rural areas and their religion influence their consumption of sorghum products. Sorghum is seen as being healthy, nutritious and traditional, but inconvenient to cook and preserve. Millet, which is not readily available in Polokwane, is considered old-fashioned. A ‘need for tradition’, or its opposite, a ‘need for modernity’, among consumers underlies their demand for products derived from indigenous cereals, a demand which is only partially satisfied. Many respondents would be ready to purchase products originating from small-scale farmers; some may believe that the quality of the produce of small farms is better, or may feel solidarity with small farmers and want to support them. This paper presents ideas for further investigation about the possibility of developing specific products and marketing strategies that will allow small-scale farmers to meet an unsatisfied urban demand.
Food Chemistry | 2013
H.C. Schonfeldt; Nicolette Gibson Hall
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.