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Developing and assessing the appropriateness of the preliminary food-based dietary guidelines for South Africans.Love, Penelope Valmai. January 2002 (has links)
Aim. The aim of this study was to document and provide a critical analysis of the South African Food-Based Dietary Guidelines (FBDGs) development process, and to assess the appropriateness of the proposed South African FBDGs.
To achieve this aim, specific study objectives included the following :
(1) To document and critically analyse the South African FBDGs process in relation to the 10-step development process recommended by the FAO/WHO.
(2) To assess the appropriateness of the proposed South African FBDGs in terms of consumer comprehension (perceptions, general understanding and specific interpretations), and application of the guidelines (ability to apply the guidelines when planning a typical day' s meals for their families).
(3) To assess the compatibility of the proposed South Africa FBDGs in terms of food categorisation as perceived by consumers, and as depicted in the food guides that are commonly used. Methodology. An extensive literature review on the development of international dietary guidelines, the emergence of FBDGs and the FAO/WHO FBDGs process, together with documentation of the South African FBDGs process, was used to critically analyse the process used for developing the proposed South African FBDGs. Focus group discussions (n=15) and structured individual interviews (n=230) were held in ten magisterial districts within KwaZulu Natal (KZN), randomly selected according to settlement strata (rural, urban informal, urban formal) and ethnicity (Black, Indian, White) to reflect the KZN population. Participants were women with no formal nutrition training, who made the food purchasing and preparation
decisions in the household. A total of 103 women participated in the focus group discussions and 230 women in the structured individual interviews. Results. The process followed by the SA FBDG Work Group has ensured that the proposed South African FBDGs are country-specific in that each FBDG is evidence-based and relates to specific nutrition-related public health concerns of South Africans. Except for the "Eat healthier snacks" FBDG, participants understood and interpreted the FBDGs as intended by health professionals, and could construct a day's meals to reflect the FBDGs. Only two other FBDGs were identified as confusing in terms of terminology used, namely, "legumes" and "foods from animals". By rewording these guidelines the FBDGs would be highly compatible in terms of personal food categorisation. Use of food guides was low, mainly due to a lack of knowledge about how to use
them. In terms of food categorisation as depicted by the reportedly most commonly used food guides (3- and 5- Food Group Guides), these food guides are incompatible with the proposed FBDGs. Conclusions. Within the South African context, the FAO/WHO FBDGs development process was feasible and practical to implement. However, to ensure sustainability of the South African FBDGs process, it is strongly recommended that the Department of Health appoint a representative scientific committee specifically for the purpose of reviewing and reformulating the South African FBDGs. Results indicate that a single set of FBDGs can be appropriate for all South Africans provided that certain guidelines are reworded as suggested; and that all the guidelines are accompanied by explanatory information citing commonly consumed foods/drinks as well as practical examples of how to apply the guidelines in light of perceived barriers. In terms of the appropriateness of food guides commonly used in South Africa, there is a need to either move away from the concept of food groups and/or to develop a new South African food guide that is compatible with the proposed FBDGs. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2002.
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The development of a valid and reliable nutrition knowledge questionnaire and performance-rating scale for urban South African adolescents participating in the 'Birth-to-Twenty' studyWhati, Lindiwe Harriet 04 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: The Birth to Twenty (BTT) study involves the monitoring of the health status and related factors of urban-born children from birth until age twenty. When the cohort reached age 13 years in 2003, nutrition knowledge assessment was identified as an important new priority and a nutrition knowledge questionnaire was required for these purposes. Subsequently a valid and reliable nutrition knowledge questionnaire was developed for the BTT study. This process started with the development of a conceptual framework of nutrition-related issues facing urban South African adolescents and identification of related nutrition concepts. A pool of potential questionnaire items reflecting the concepts was subsequently developed. These items were evaluated by an expert panel to ensure content and face validity before being structured into a questionnaire. The resulting 88-item questionnaire was completed by adult and adolescent samples, each age group comprising subgroups of those likely to have good nutrition knowledge and those likely to have poor nutrition knowledge. The data obtained from the completion of the questionnaire by these groups was used to refine the questionnaire through the determination of difficulty and discriminatory indices of the items, and the deletion of items that did not meet the stated criteria. The construct validity of the remaining 63 items was assessed using the same data set. To assess the internal consistency reliability (ICR) of the 63-item questionnaire it was completed by an adolescent sample population considered to be representative of the BTT cohort, after which the questionnaire underwent further steps of refinement. The result was a 60-item questionnaire of which the ICR and construct validity was reassessed and found to be satisfactory. However, to ensure the accurate interpretation of scores obtained by testees, the development of a performance-rating scale was necessary.
A norm-referenced performance-rating scale (norms) was developed by administering the nutrition knowledge questionnaire to a sample population similar to the BTT cohort (norm group) and transforming their performance scores to z-scores. The z-scores ranges were then categorised into stanines, thereby resulting in a norm-referenced performance-rating scale that can be used to rate the performance of the BTT cohort. The validity of the norms was assessed by administering the nutrition knowledge questionnaire to three validation groups that comprised groups who were expected to obtain different performance-ratings on the questionnaire based on their varying levels of nutrition knowledge. The validation groups performed as expected, with significant differences in performance-rating profiles found among the three groups, indicating the validity of the norms. The study was successful in developing a reliable and valid nutrition knowledge questionnaire for use on the urban adolescents who participate in the BTT study. A norm-referenced performance-rating scale for use with the questionnaire was also successfully developed. The questionnaire and norms will be useful in assessing nutrition knowledge as well as in comparing the changes in knowledge of the BTT cohort as they move from lower to higher school grades. / AFRIKAANSE OPSOMMING: Die “Birth to Twenty” (BTT)-studie behels die monitering van die gesondheidstatus en verwante faktore van kinders wat in stedelike gebiede gebore is van geboorte tot twintigjarige ouderdom. Toe die kohort in 2003 dertienjarige ouderdom bereik het, is die evaluering van die voedingkennis van die kinders as ‘n belangrike nuwe prioriteit geïdentifiseer. ‘n Toepaslike voedingkennisvraelys is vir hierdie doeleindes benodig en gevolglik is ‘n geldige en betroubare vraelys vir gebruik in die BTT-studie ontwikkel. Hierdie proses is begin deur die ontwikkeling van ‘n konseptueleraamwerk oor voedingverwante vraagstukke wat stedelike Suid-Afrikaanse adolessente in die gesig staar, asook die identifisering van verwante voedingkonsepte. ‘n Poel van potensiële vraelysitems wat die konsepte reflekteer is daarna ontwikkel. Die items is eers deur ‘n paneel van kenners evalueer om inhoud- en gesigsgeldigheid te verseker alvorens dit in ‘n vraelys omskep is. Die produk was ‘n vraelys wat 88 items ingesluit het wat vervolgens deur volwasse en adolessente groepe voltooi is. Die groepe het subgroepe ingesluit van diegene met verwagte goeie voedingkennis en diegene met verwagte swak voedingkennis. Die data wat tydens hierdie stap gegenereer is, is gebruik om die vraelys verder te verfyn deur die bepaling van die moeilikheids- en diskriminatoriese-indekse van die items. Die items wat nie aan vooraf gestelde kriteria voldoen het nie, is weggelaat. Die konstrukgeldigheid van die oorblywende 63 items is bepaal deur dieselfde datastel te gebruik. Om die interne-konsekwensie-betroubaarheid (IKB) van die vraelys te bepaal, is dit deur ‘n steekproef van adolessente, wat verteenwoordigend van die BTT-kohort is, voltooi. Hierna is die vraelys verder verfyn. Die uitkoms was ‘n 60-item vraelys waarvan die IBR en konstrukgeldigheid weereens bepaal is. Dit is gevind dat dié twee indikatore van geldigheid en betroubaarheid bevredigend is. Om akkurate interpretasie van die punt wat deur ‘n respondent vir die toets behaal te verseker, is die ideal om ‘n skaal te ontwikkel wat gebruik kan word om dié punt te takseer.
‘n Norm-gebaseerde prestasietakseringskaal is ontwikkel deur die voedingkennisvraelys deur ‘n steekproef wat verteenwoordigend is van die BTT-kohort (normgroep), te laat voltooi. Die prestasiepunte is getransformer na z-tellings wat vervolgens getransformeer is na stanneges, wat ‘n norm-gebaseerde prestasietakseringskaal opgelewer het wat gebruik kan word om die prestasie van die BTT-kohort te takseer. Valideringsgroepe met verskillende vlakke van voedingkennis, wat dus na verwagting verskillend getakseer behoort te word indien die norme toegepas word, het die voedingkennisvraelys voltooi om die geldigheid van die norme te bepaal. Dié valideringsgroepe het soos voorspel presteer, met betekenisvolle verskille in die prestasieprofiele van die verskillende groepe. Hierdie resultate dui daarop dat die norme geldig is.
Die ontwikkeling van ‘n geldige en betroubare voedingkennistoets vir gebruik in die BTT-studie is suksesvol in hierdie studie deurgevoer. ‘n Norm-gebaseerde prestasietakseringskaal vir gebruik saam met die vraelys is ook suksesvol ontwikkel. Die vraelys en norme sal van waarde wees vir die evaluering van die voedingkennis van die BTT-kohort. Dit sal ook met sukses gebruik kan word om die verandering in die voedingkennis van die kinders soos wat hulle ouer word, te bepaal.
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Market and product assessment of probiotics and prebiotics and probiotic strains for commercial useBrink, Marelize 03 1900 (has links)
Thesis (MSc Nutrition Science)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Probiotics (live microbes) and prebiotics (non-digestible food-ingredients) are rapidly gaining interest
worldwide as supplements and functional food ingredients but little South African information in this
regard is available. Furthermore, the availability of South African produced probiotic concentrates for
commercial use is also very limited. The aims of this study therefore were to complete a market and
product assessment of probiotic and prebiotic containing products in South Africa and to evaluate
probiotic strains for commercial use in South Africa.
For the purposes of market and product assessment probiotic and/or prebiotic containing products
manufactured in South Africa were identified. The scientific and legal correctness of health and
content claims made on the labels of the products were assessed. An exploratory survey was
conducted to determine the awareness of South African consumers of probiotics and prebiotics. For
the evaluation of probiotic strains for potential commercial use in South Africa, a panel of twelve
lactic acid bacteria (LAB) were screened for inhibitory activity against two porcine pathogens and
indicator strains from the LMG-panel isolated from the faeces of patients diagnosed with AIDS. The
five LAB with the best inhibitory activity were tested for growth in soymilk-base and for the effect of
lyophilization on the inhibitory activity thereof. The effect of prebiotics on the growth and inhibitory
activity of the strains was tested in vitro.
A range of products containing probiotics and prebiotics available on the South African market was
identified. Irregulatories concerning health claims on the labels were found, but content claims
seemed to be less of a problem. The results also indicate that the proposed South African regulations
for the labelling of probiotic and prebiotic containing products need to be revised to include the
probiotic and prebiotic related health claims for which sufficient scientific evidence is available. The
probiotic strains with potential for commercial use in South Africa that were identified, include
Lactobacillus plantarum 423, Lactobacillus casei LHS, Lactobacillus salivarius 241, Lactobacillus
curvatus DF38 and Pediococcus pentosaceus 34. These strains were grown successfully in soymilkbase
and lyophilization did not have a negative effective on the inhibitory activity thereof. The growth
and inhibitory activity of the five LAB were promoted when combined with 1% (w/v)
Raftilose® Synergyl .
It is concluded that although a variety of probiotic and prebiotic containing products are available on
the South African market, the scientific and legislative correctness of especially health related claims
is not satisfactory and that South African consumer awareness of these products is low. It is also
concluded that a combination of at least three of the five identified LAB and 1% Raftilose® Synergy can be used by South African manufacturers for the production of probiotic and
prebiotic containing supplements. / AFRIKAANSE OPSOMMING: Die belangstelling in probiotika (lewendige mikrobe) en prebiotika (onverteerbare
voedselbestanddele) as supplemente en funksionele voedselbestanddele is besig om wêreldwyd toe te
neem, alhoewel weinig Suid-Arikaanse inligting in hierdie verband beskikbaar is. Die beskikbaarheid
van Suid-Afrikaans geproduseerde probiotika konsentrate vir kommersïele gebruik is ook baie beperk.
Die doelwitte van hierdie studie was dus om 'n mark- en produkevaluering van probiotika- en
prebiotika-bevattende produkte in Suid-Afrika uit te voer en om probiotiese stamme te evalueer vir
uiteindelike kommersiële gebruik in Suid-Afrika.
Vir die doel van die mark- en produkevaluering is probiotika- en prebiotika-bevattende produkte wat
in Suid-Afrika vervaardig word geïdentifiseer. Die wetenskaplike en wetlike korrektheid van die
gesondheids- en inhoudsaansprake op die etikette van die produkte is evalueer. 'n Markopname is
uitgevoer om die bewustheid van Suid-Afrikaanse verbruikers van probiotika en prebiotika vas te stel.
Vir die evaluering van probiotiese stamme vir potensïele kommersiële gebruik in Suid-Afrika is 'n
paneel van twaalf melksuurbakteriëe getoets vir inhibitoriese aktiwiteit teen twee patogene geïsoleer
uit varke asook teen indikator stamme van die LMG-paneel. Die vyf melksuurbakteriëe met die beste
inhibitoriese aktiwiteit is getoets vir groei in sojamelk-basis en ook vir die effek van vriesdroging op
die groei en inhibitoriese aktiwiteit van die stamme daarvan. Die effek van prebiotika op die groei en
inhibitoriese aktiwiteit van die stamme is in vitro getoets.
'n Reeks van probiotika- en prebiotika-bevattende produkte wat beskikbaar is op die Suid-Afrikaanse
mark, is geidentifiseer. Ongeruimdhede met die gesondheidsaansprake op die etikette is gevind, maar
inhoudsaansprake was minder problematies. Die resultate dui ook daarop dat die voorgestelde Suid-
Afrikaanse regulasies vir die etikettering van probiotika- en prebiotika-bevattende produkte hersien
moet word om al die probiotika- en prebiotika-verwante gesondheidsaansprake waarvoor voldoende
wetenskaplike bewyse beskikbaar is in te sluit. Die probiotiese stamme met potensiaal vir
kommersiële gebruik in Suid-Afrika sluit die volgende in: Lactobacillus plantarum 423, Lactobacillus
casei LHS, Lactobacillus salivarius 241, Lactobacillus curvatus DF 38 en Pediococcus pentosaceus
34. Hierdie stamme is suksesvol gekweek in sojamelk-basis en vriesdroging het nie' n negatiewe
effek op die groei en inhibitoriese aktiwiteit daarvan gehad me. Die kombinasie van die vyf
melksuurbakteriëe met 1% Raftilose® Synergy het die groei en inhibitoriese aktiwiteit daarvan
bevorder.
Die gevolgtrekking wat gemaak word is dat alhoewel 'n varrasie van probiotika- en prebiotikabevattende
produkte beskikbaar is op die Suid-Afrikaanse mark, die wetenskaplike en wetlike
korrektheid van spesifiek die gesondheids-verwante aansprake op die etikette daarvan nie bevredigend
is nie en dat die bewustheid van die Suid-Afrikaanse verbruikers van hierdie produkte laag is. Die gevolgtrekking kan ook gemaak word dat 'n kombinasie van ten minste drie van die vyf
geïdentifiseerde melksuurbakteriëe en 1% Raftilose® Synergy deur Suid-Afrikaanse vervaardigers
gebruik kan word vir die vervaardiging van produkte wat probiotika en prebiotika bevat.
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Efficacy and safety of acidified enteral formulae in tube fed patients in an intensive care unit / Acidified formulae in ICU patientsKruger, Jeanne-Marie 03 1900 (has links)
Thesis (MNutr (Human Nutrition))--University of Stellenbosch, 2006. / INTRODUCTION: The primary objective was to determine whether acidified formulae (pH 3.5 and
4.5) decreased gastric and tracheal colonisation, as well as microbial contamination of the enteral
feeding delivery system, compared with a non-acidified control formula (pH 6.8) in critically ill
patients. Secondary objectives included tolerance of the trial formulae and mortality in relation to
the administration of acidified formulas.
DESIGN: The trial was a controlled, double-blinded, randomised clinical trial of three parallel
groups at a single centre.
METHOD: Sixty-seven mechanically ventilated, medical and surgical critically ill patients were
randomised according to their APACHE II scores and included in the trial. Patients received either
an acidified (pH 3.5 or 4.5) or control polymeric enteral formula via an 8-Fr nasogastric tube at a
continuous rate. Daily samples were taken for microbiologic analyses of the enteral formulae at
various stages of reconstitution and at 6-hour and 24-hour intervals during administration thereof
(feeding bottle and delivery set). Daily patient samples included nasogastric and tracheal
aspirates, haematological evaluation and gastro-intestinal tolerance. The trial period terminated
when patients were extubated, transferred from the ICU, enteral nutrition became contraindicated,
a patient died, or for a maximum of 21 days.
RESULTS: Gastric pH showed no significant difference (p = 0.86) between the 3 feeding groups
[pH 3.5 (n = 23), pH 4.5 (n = 23) and pH 6.8 (n = 21)] at baseline prior to the administration of
enteral formulae. After initiation of feeds, the gastric pH decreased significantly (p< 0.0001) in the
acidified formulae as compared to the control formula during the trial period. Patients who
received acidified enteral formulae (pH 3.5 and 4.5) had significantly less (p < 0.0001)
contamination from the feeding bottles and delivery systems in respect of Enterobacteriacea, and
Enterococcus., The more acidified group (pH 3.5) showed significantly less gastric contamination
(p = 0.029) with Enterobacteriacea, , but not for fungi. The 3.5 acidified group also had the lowest
gastric growth in terms of colony counts (≤104) of these organisms, but not for fungi, when
compared to the control group (≤105). Vomiting episodes were 22% and abdominal distension
12%, with a higher incidence in the control group. Adverse events occurred equally between the
groups with a higher, but not significantly different incidence of 37% in the control group and 32%
for the acidified groups. There was no evidence of gastro-intestinal bleeding in any patient.
Overall, the mortality rate in this trial was 6%, with 6.5% for the acidified groups (n=46) and 4.8%
for the control group (n=21), a statistically insignificant difference.
CONCLUSION: Acidified enteral formulae significantly decrease gastric colonisation by
preserving gastric acidity that decreases the growth of Enterobacteriaceaes organisms. Acidified
formulae significantly decrease bacterial contamination of the enteral feeding system (bottle and
delivery set) of Enterobacteriaceae and Enterococcus organisms. Acidified formulae are tolerated
well in critically ill patients.
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Micronutrient supplementation for critically ill adults : a systematic review of the evidenceVisser, Janicke 12 1900 (has links)
Thesis (MNutr (Human Nutrition))--Stellenbosch University, 2008. / Background
Critical illness is associated with increased production of reactive oxygen species
and oxidative stress, and low levels of most micronutrients with resultant diminished
endogenous antioxidant defences. Micronutrient supplementation is thought to be
beneficial to the critically ill patient by ameliorating oxidative stress and by improving
clinical outcome.
Objectives
This systematic review assessed the effects of micronutrient supplementation on
adults recovering from critical illness. Primary outcomes included clinical endpoints
[mortality, infectious complications, length of intensive care unit and hospital stay
(LICU and LOS)]. Secondary outcomes included descriptions of practice issues,
micronutrient status, morbidity, course of the acute phase response and oxidative
stress.
Search strategy
An electronic bibliographic database search was carried out, bibliographies of
retrieved articles were reviewed and personal files searched to obtain additional
citations. Databases were searched from inception until 29 February 2008.
Selection criteria
Randomized controlled trials (RCTs) of micronutrient supplementation (by any route)
in adult critically ill patients, given in addition to their routine care, were included.
Data collection and analysis
Two authors independently extracted data and assessed trial quality. For the primary
outcomes the random-effects model was used to estimate overall relative risk /
mean difference and effect size due to the presence of study heterogeneity.
Selected exploratory analyses were undertaken. Differences at the level of p<0.05
was considered to be statistically significant. The secondary outcomes were sparse
and variably recorded such that this data was not formally aggregated.
Main results
Fifteen RCTs involving 1714 participants and 18 RCTs involving 1849 participants were
included for the primary and secondary objectives respectively. The quality of the
RCTs, as reported, was disappointing, particularly for allocation concealment.
Fourteen trials (n=1468) of micronutrient supplementation showed a statistically significant reduction in overall mortality [relative risk (RR) 0.78, 95% confidence
interval (CI) 0.67-0.90, I2=0%, p=0.0009]. An asymmetrical funnel plot necessitates
caution when directly interpreting these results. Six RCTs (n=1194) indicated a
statistically significant reduction in 28 day mortality (RR 0.75, 95% CI 0.63-0.88, I2=0%,
p=0.0006) (symmetrical funnel plot). Micronutrient supplementation in this systematic
review was not associated with a reduction in infectious complications, LICU or LOS.
In sub-group analyses, single nutrients were associated with borderline statistical
significance (RR 0.82, 95% CI 0.66-1.01, I2=0%, p=0.06) in terms of mortality, whist a
sensitivity analysis of combined micronutrients indicated a significant reduction in
mortality (RR 0.69, 95% CI 0.54-0.90, I2=2%, p= 0.006). This review did not find clear
evidence that parenteral is superior to enteral administration in terms of clinical
outcomes. The secondary outcomes confirmed that timing, duration and dosing are
key factors to ensure optimal clinical benefit.
Conclusion
This review does suggest potential benefit of micronutrient supplementation in
critically ill adults for some clinical outcomes (especially mortality), but also highlights
that caution is warranted as nutrient interactions and risk of toxicity are not clearly
defined in critical illness. More large multi-centre randomized trials are necessary to
assess the effects of different types and doses of micronutrient supplementation in
selected groups of patients with different types of critical illness.
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Nutritional quality and consumer acceptability of provitamin A-biofortified maize.Pillay, Kirthee. January 2011 (has links)
Vitamin A deficiency (VAD) is a major public health problem in developing countries, including South Africa. The potential of provitamin A-biofortified maize for use as a complementary strategy to alleviate vitamin A deficiency in developing countries, where maize is the dominant staple food, is currently a subject of research. Although the nutritional composition of white maize is thought to be similar to that of biofortified maize, apart from the differences in provitamin A carotenoid content, the comparative nutritional composition of the two maize types seems not to have been subjected to a comprehensive scientific study. When setting the target level of provitamin A in the provitamin A-biofortified maize, it is important to consider the potential effect of processing on the final provitamin A carotenoid content of the biofortified food products, as the provitamin A carotenoids levels may decrease on processing. Furthermore, the yellow/orange provitamin A-biofortified maize may not be widely accepted by African consumers who are vulnerable to VAD, and are traditional consumers of white maize.
This study firstly aimed to evaluate the nutritional composition, including provitamin A composition, and grain quality of provitamin A-biofortified maize varieties, compared to white maize. The second aim was to assess the effect of processing (milling and cooking) on the retention of provitamin A carotenoids and other nutrients in popular South African maize food products prepared with provitamin A-biofortified maize. Thirdly, the study aimed to assess the acceptability of maize food products prepared with provitamin A-biofortified maize by consumers of different age and gender in rural KwaZulu-Natal, South Africa.
The grains of the provitamin A-biofortified maize varieties and grain of a white maize variety (control) were analysed for their nutritional composition using standard or referenced methods. The carotenoid content of the grains was analysed by High-Performance Liquid Chromatography (HPLC) and mass spectroscopy. The provitamin A carotenoids β-cryptoxanthin, and trans and cis isomers of β-carotene, and other unidentified cis isomers of β-carotene were detected in varying levels in the provitamin A-biofortified maize varieties. The total provitamin A content in the biofortified maize varieties ranged from 7.3-8.3 μg/g dry weight (DW), with total β-carotene ranging from 3.5-3.6 μg/g DW, and β-cryptoxanthin from 3.7-4.8 μg/g DW, whilst no carotenoids were detected in the white maize variety. Results of the evaluation of the content of other nutrients showed that, when compared with the white maize variety, the provitamin A-biofortified maize varieties had higher levels of starch, fat and protein but were lower in iron.
The zinc and phosphorus levels in the white maize and the biofortified maize were comparable. The biofortified maize varieties were better sources of most of the essential amino acids relative to the white maize, but, similar to the white maize, they were deficient in histidine and lysine, indicating that further improvement is required. Selected quality attributes (grain density, susceptibility of kernels to cracking, milling quality and resistance of the kernels to fungal infection) of grains of 32 provitamin A-biofortified maize varieties and a white variety (control) were assessed. Overall, the quality of the grains of the provitamin A-biofortified maize varieties were found to be superior to that of the white maize grain, although the biofortified maize grains showed less resistance to fungi, including mycotoxin-producing types. This indicates that the trait of grain resistance to infection by fungi should also be incorporated in the provitamin A-biofortified maize varieties during breeding.
To assess the retention of provitamin A carotenoids and other nutrients in maize food products, three selected provitamin A-biofortified maize varieties and the control (white maize variety) were milled into mealie meal and samp. The milled products were cooked into three products: phutu and thin porridge (from the mealie meal) and cooked samp. Nutrient retention during processing was determined. Milling resulted in either an increase or slight decrease in the provitamin A carotenoid levels, but there was no major decrease in the total provitamin A level. Most of the other nutrients were well retained during milling, but there were substantial losses of fibre, fat and minerals. Provitamin A carotenoid levels decreased on cooking. In phutu 96.6 ± 20.3% β-cryptoxanthin and 95.5 ± 13.6% of the β-carotene was retained after cooking. In thin porridge 65.8 ± 4.6% β-cryptoxanthin and 74.7 ± 3.0% β-carotene; and in samp 91.9 ± 12.0% β-cryptoxanthin and 100.1 ± 8.8% of the β-carotene was retained after cooking, respectively. Provitamin A retention seemed to be influenced by both maize variety and food form, indicating that suitable varieties and food forms should be found. There was generally a high retention of the other nutrients in all the three cooked products, except for the substantial losses of fat in thin porridge and iron and phosphorus in cooked samp. These findings indicate that an optimal delivery of provitamin A to the consumer can be achieved by processing provitamin A-biofortified maize into foods that have a good retention of provitamin A carotenoids, such as phutu and samp. These food products would be recommended in areas where VAD is prevalent.
In order to assess consumer acceptability of provitamin A-biofortified maize, a total of 212 subjects aged 3-55 years from Mkhambathini Municipality, in KwaZulu-Natal province, South Africa, participated in the sensory evaluation of phutu, thin porridge and cooked samp prepared with provitamin A-biofortified maize varieties and a white variety (control). Preference for yellow maize food products was negatively associated with an increase in the age of the subjects. Overall, preschool children preferred yellow maize to white maize food products: phutu (81% vs. 19%), thin porridge (75% vs. 25%) and samp (73% vs. 27%). In contrast, primary school children preferred white maize to yellow maize food products: phutu (55% vs. 45%), thin porridge (63% vs. 38%) and samp (52% vs. 48%). Similarly, secondary school children and adults also displayed a similar preference for white maize food products. There was no association between gender and preference for maize variety. Focus group discussions revealed that participants had a negative attitude towards biofortified maize due to its colour, taste, smell and texture. However, the participants expressed a willingness to consume biofortified maize if it was cheaper than white maize and was readily available in local grocery stores. These findings indicate that there is a potential to promote the consumption of provitamin A-biofortified maize and its food products in this part of South Africa, thereby contributing to a reduction in the incidence of VAD.
This study has shown that provitamin A-biofortified maize has a good potential to be used as an additional strategy to alleviate VAD in poor communities of South Africa, including similar environments in sub-Saharan Africa. However, the study has revealed that there are still challenges to be overcome in order to achieve the target provitamin A content of 15 μg/g in provitamin A-biofortified maize, set by HarvestPlus, an international challenge program. This may also explain why provitamin A-biofortified maize varieties with this level of provitamin A have been scarcely reported in the literature. Thus, more research is required to achieve the target provitamin A level in maize by conventional breeding. The results of this study indicate that besides provitamin A, the biofortified maize is also a good source of other nutrients including starch, fat, protein and zinc. However, improving the consumer acceptability of the provitamin A-biofortified maize remains a challenge, due to the negative attitudes towards the yellow/orange maize by African consumers. On the other hand, the results of this study indicate that there is an opportunity to promote the consumption of provitamin A-biofortified maize food products by preschool children, a finding which has not been previously reported in the literature. Nutrition education on the benefits of provitamin A-biofortified maize, as well as improved marketing are recommended, in this part of South Africa and also in similar environments in other sub-Saharan countries. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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The effect of Lactobacillus reuteri supplementation on anthropometric measurements, lung function and lung infections in a cystic fibrosis population in KwaZulu-Natal.Read, A. J. P. January 2007 (has links)
BACKGROUND: Cystic fibrosis (CF) patients grow poorly and tend to be malnourished. They frequently suffer from lung infections necessitating the repeated use of antibiotics.
AIM: This study was conducted to determine whether supplementation with a probiotic Lactobacillus reuteri (L. reuteri) could reduce the incidence and duration of lung infections, and whether this would impact on their anthropometric data. The secondary purpose was to compare the nutritional status of the CF patients attending CF clinics in Kwazulu-Natal (KZN) with CF patients attending CF clinics in Cape Town (CT).
METHODS: Twenty three CF patients 6-31 years of age from 2 CF clinics in Kwazulu-Natal started the study although only 16 patients completed it. The study was a randomized, double blind, placebo controlled crossover trial with six months on placebo and six months on probiotic. Weight, height, mid arm circumference (MAC), triceps skin fold thickness (TSF), forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were measured, sputum collected and a symptom diary completed over the 12 month period. Anthropometric data of CF patients attending CF clinics in CT was obtained from the publication by Westwood & Saitowitz (1999).
RESULTS: Compliance with taking the L. reuteri was poor. Most took only 50% of the required daily dose. Probiotic supplementation showed a slight (non significant) trend to improve FEV1 and FVC, while no significant difference could be seen in the number and duration of the lung infections. Sputum analysis showed a non significant trend towards the probiotic reducing the number of bacteria in the sputum. There was a significant reduction of symptoms for fever, running nose, sore throat and ear ache while on placebo. There was a significant increase in weight gained off probiotic compared to the probiotic period. The changes in height, weight for age (WFA) percentiles, height for age (HFA) percentiles, WFA and HFA Z-scores, percentage expected weight for age and percentage expected height for age all showed no difference whether on or off probiotic. Over half the CF children in the KZN clinics were underweight for their actual height compared to one third in the CT clinics with a higher number of subjects below the 5th percentile for MAC and TSF readings compared to CT.
CONCLUSION: Due to a small sample size and poor compliance no firm conclusions could be drawn. However a slight (non significant) improvement could be seen in favour of the probiotic for FEV1, FVC, and sputum analysis. Although all other findings were not significantly different it would be of benefit to carry out further investigation with improved compliance with the probiotic to see if the parameters set out above could be improved. The KZN and CT CF groups were comparable and the nutritional status of CF patients on KZN was well below that of the CT CF clinics and further monitoring would need to be carried out.
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The use and interpretation of the nutrition information on the food label of selected fat spreads by female consumers aged 25-45 years, living in Pietermaritzburg.Wiles, Nicola Laurelle. January 2006 (has links)
Aim: To determine the use and interpretation of the nutrition information on the food label of selected fat spreads by female consumers aged 25 to 45 years, living in Pietermaritzburg.
Objectives: This study set out to determine the following objectives regarding the food label: what the demographics of the consumers making use of the label were; how these consumers used the label and their motivation behind this label use and did the use of the label alter the purchase of that product?
Method: One hundred and fifty women aged 25-45 years were chosen from an accidental, non-probability sample of consumers shopping at selected supermarkets within Pietermaritzburg. Respondents were presented with a four part questionnaire surrounding the purchase of selected fat spreads.
Results: The greatest number of respondents were from the white population group (n = 65), followed by black respondents (n = 46), Indian respondents (n = 29) and then coloured respondents (n = 10). Results showed that the respondent who was most likely to use the nutrition information on the food label had a tertiary education; was a primary food purchaser, lived with other people, had more than R1000 a month to spend on food and was conscious of choosing the healthier option. Fifty five percent of this study sample (n = 82) claimed to use the nutrition information on the label to assist with purchases and 68% (n = 102) found the nutrition information important for purchasing a new product. Of the potential factors that have previously been found to impede the use of the nutrition information label:-inadequate print size, lack of education as well as lack of nutrition information on the food label were found to be factors restricting label use in this study. The most commonly used sources of nutrition information were the media as well as friends and family and the most trusted source was the Health Professional.
Discussion: If the nutrition information is to be used both correctly and effectively, there must be a major educational campaign that sets out to meet the needs of the population that are most vulnerable, especially those with an inadequate education.
Conclusion: The consumer most likely to use the nutrition information on the food label has a tertiary education, is a primary food purchaser with a large amount of money available for groceries and is conscious of choosing a healthier option. The label is most likely to be used when purchasing a fat spread for the first time. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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The hydration status, fluid and carbohydrate intake of male adolescent soccer players during training in Pietermaritzburg, KwaZulu-Natal.Gordon, Reno. January 2012 (has links)
Adolescent athletes of this era are more pressurized than adolescents of previous generations to
perform at an optimum level (Micheli & Jenkins 2001, p49). The importance of winning can result
in adolescent athletes developing inappropriate nutritional practices such as neglecting hydration
and consuming insufficient carbohydrate (Micheli & Jenkins 2001, p57). Consuming insufficient
fluid leads to dehydration which reduces a soccer player’s ability to continue training. Consuming
inadequate carbohydrate reduces performance and blood glucose levels during training. This study
aimed to determine the hydration status, fluid and carbohydrate intake of male, adolescent soccer
players during training.
A cross-sectional study was conducted among 122 amateur male, adolescent soccer players (mean
age = 15.8 ± 0.8 years; mean BMI = 20.4 ± 2.0 kg/m2). The players’ hydration status before and
after training, was measured using urine specific gravity and percent loss of body weight. Their
carbohydrate intake, as well as the type and amount of fluid consumed, were assessed before,
during and after training. A questionnaire was administered to determine the players’ knowledge
regarding the importance of fluid and carbohydrate for soccer training.
The study had an 87.1% response rate. The mean environmental conditions did not predispose
players to heat illness. However, the players were at risk of developing heat illness during six of
the 14 training sessions. Although the mean urine specific gravity indicated that players were
slightly dehydrated before and after training, 43.8% of players were very or extremely dehydrated
before training and 53.6% after training. A few (3.3%) were extremely hyperhydrated before
training and after training (7.0%). On average players lost less than 1% of body weight during
training and less than 3% of players dehydrated more than 2%.
Players consumed mainly water before (289.17 ± 206.37 ml), during (183.20 ± 158.35 ml) and
after (259.09 ± 192.29 ml) training. More than 90% stated that water was the most important fluid
to consume before, during and after training. Very few (4.7%) correctly stated that carbohydrate
should be consumed before, during and after training.
Players were found to be slightly dehydrated before and after training and therefore were not
consuming enough fluids during training. Players consumed inadequate amounts and types of fluid
and carbohydrate. This not only compromises their performance but also health. Players were not
aware of the importance of fluid and carbohydrate for soccer training.
This study is unique in that it focused on the carbohydrate and hydration practices of socioeconomically
disadvantaged adolescent soccer players during training. The study sample therefore
represents a high risk group about which there is limited published data both locally and
internationally. This study generated important baseline information which was lacking before on
the hydration status, fluid and carbohydrate intake of adolescent soccer players in South Africa. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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Nutritional composition and acceptance of a complimentary food made with provitamin A-biofortified maize.Govender, Laurencia. 13 May 2014 (has links)
Introduction: Micronutrient malnutrition has been identified as a serious health problem globally and is on the rise in South Africa. This is evident from the escalating burden of vitamin A deficiency (VAD) in South Africa. Rural infants are the most affected, as their diets often lack micronutrients. Food fortification, vitamin A supplementation and dietary diversity are the strategies that have been employed in South Africa to alleviate VAD. However, these strategies have not been effective, for various reasons. Biofortification is the production of micronutrient dense staple crops to alleviate micronutrient deficiencies. This strategy could complement existing strategies in the alleviation of VAD in South Africa and in other countries, especially in sub-Saharan Africa (SSA), where VAD is prevalent.
Aim: The aim of this study was to investigate the nutritional composition and acceptance of a complementary food (soft porridge) made with provitamin A-biofortified maize by female infant caregivers from the rural areas of Umgungundlovu District of KwaZulu-Natal, South Africa.
Objectives: (i) To evaluate the nutritional composition of soft porridge made with provitamin A-biofortified maize compared to non-biofortified white maize porridge; (ii) To assess the sensory acceptability of soft porridge made with the biofortified maize by black African female infant caregivers of varying age; and (iii) To determine the perceptions of the black African infant caregivers about the biofortified maize relative to the non-biofortified white maize.
Methods: A cross-sectional study was conducted. Grains of two provitamin A-biofortified maize varieties and one white variety (control) were used. Grain and soft porridge of each variety of maize were analysed for their nutritional composition. The sensory acceptability of the porridges were evaluated by black African female infant caregivers, using a five-point facial hedonic scale. Focus group discussions were conducted, using some of the study subjects, to determine their perceptions about the provitamin A-biofortified maize.
Results: The results showed that the grains of the provitamin A-biofortified maize varieties and their soft porridges were more nutritious than the control white variety in terms of energy, fibre, fat, protein, iron, zinc and phosphorus content. The results of the sensory evaluation indicated that there was no significant difference in the sensory acceptability of the biofortified soft porridges and the white maize soft porridge, irrespective of the age of the
sensory evaluation panellists. The female caregivers perceived the biofortified maize as nutritious and health-beneficial and thought that infants would like its unique yellow colour and taste. However, the black African female caregivers perceived the provitamin A-biofortified maize as an animal feed or food for the poor. Nevertheless, the female caregivers expressed a willingness to give their infants porridge made with provitamin A-biofortified maize if it was cheap, readily available and health-beneficial.
Conclusion: This study suggests that provitamin A-biofortified maize has the potential to be used as a complementary food item. Biofortification of maize with provitamin A could be used as a possible complementary strategy to assist in the alleviation of VAD in SSA. Furthermore, the relatively higher energy, fibre, fat, protein, iron, zinc and phosphorus content of the biofortified maize could contribute to the alleviation of protein-energy malnutrition and mineral deficiencies, respectively, which are prevalent in children of SSA. Although the findings of this study, like other previous studies, indicate that there are some negative perceptions about the provitamin A-biofortified maize, this study shows that provitamin A-biofortified maize soft porridge is as acceptable as white maize soft porridge to female infant caregivers from the rural areas of Umgungundlovu District of KwaZulu-Natal, South Africa. The female caregivers are thus likely to accept the biofortified maize for use as an infant complementary food in the form of soft porridge. Further research is recommended to expand the study area and consumer sample size in order to increase the confidence of inferring these results for large rural populations. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.
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