Theses and dissertations (Applied Sciences)
Permanent URI for this collectionhttp://ir-dev.dut.ac.za/handle/10321/6
Browse
5 results
Search Results
Item Trans fatty acid content in used vegetable cooking oil and food safety hygiene practices of informal food vendors in Warwick Triangle, Durban(2023-05) Rubushe, Mthokozisi; Napier, Carin E.; Mdluli, Phumlane SelbyAim: The aim of the study was to determine the food safety and hygiene practices and the safety levels of cooking oil used, by the informal food vendors in the Warwick Triangle Avenue (WTA) to prepare meals to sell to consumers by determining the trans-fatty acid content of the cooking oil used. Objectives: The specific objective of the study is to investigate the oil safety, hygiene practices and food safety knowledge of informal food vendors at the WTA in eThekwini. Methods: A total number of 40 informal food vending outlets, scattered in the WTA, participated in the study. Fried food prepared by vendors in the WTA were either deep-fried or shallow-fried. Therefor the vendors were divided into two groups: 20 deep-frying and 20 shallow-frying groups. This study was descriptive with an analytical component. The data collection exercise was quantitative, using a socio-demographic questionnaire and a food handler’s questionnaire. A detailed observation sheet and a sheet for recording the results of 3MTM oil quality test strips were also used. Used cooking oil samples were collected in small glass bottles for lab analysis. Data was captured in Excel and analyzed using a statistical package for social science (SPSS) version 24 for descriptive statistics. Summary of Findings: Adequate cooking spaces was not present in 70.0% (n=14) of DF vendors and 65.0% (n=13) of SF vendors. Sixty-five percent (n=13) DF and 80.0% (n=16) of the SF vendors did not have access to safe water for food preparation. Most of the DF vendors (40.0%; n=8) kept food for less than 15 minutes and 30.0% (n=6) kept the food for more than 45 minutes. A small number of vendors (10.0%; n=2) kept the food from 30 to 45 minutes, while 20.0% (n=4) kept the food from 15 to 30 minutes. Most of the SF vendors (30.0%; n=6) kept food for more than 45 minutes and 25.0% (n=5) kept the food for less than 15 minutes, and 25.0% (n=5) kept the food between 15 – 30 minutes. A small number of vendors (20.0%; n=4) kept the food for 30 to 45 minutes. Cleaning or removal of rubbish by DF vendors took place once a day in 45.0% (n=9) of the cases, and twice a day in 6.0% (n=30) for the rest of the cases. Cleaning or removal of rubbish took place once a day in 5% (n=1) SF of the vending sites. Only 50.0% (n=10) of DF vendors and 30.0% (n=6) of SF vendors had rubbish bins with tightly fitting lids. Only 10.0% (n=2) of the DF vendors indicated that they clean their utensils during food preparation compared to 25.0% (n=5) of the SF vendors. The researcher's observation reveals that correct cleaning chemicals were not available in all the SF and DF vending sites (100.0%) such as detergent for clothes and sanitizers and dishwashing liquid. All the DF and SF vending sites were not sanitized during food preparation, and 65.0% (n=13) of the areas were not cleaned during food preparation. Forty-five percent (n=9) of the DF vendors changed oil daily, while 30.0% (n=6) changed the oil frequently, with 15.0% (n=3) changing the oil weekly and 10.0% (n=2) changing it seldom. Forty-five percent (n=9) of the DF vendors’ cooking oil was suitable for cooking, 20.0% (n=4) was probably suitable and 20.0% (n=4) was probably not safe depending on the quality of food and 15.0% (n=3) was not safe and had to be discarded. Gas chromatography further revealed that a value of 4.62% for methyl palmate (sample A1) was obtained implying an increase in viscosity, acid value as well as the saturation process. The highest saturation point was observed for samples A11 and A12. This effect implies an increase from C17: 1 (monosaturated) fatty acid to C17: 2 (diunsaturated) fatty acid chains. Additionally, the results obtained indicate that fats and oils experience different degrees of proportionality in saturation during frying or cooking use, with the magnitude of these changes varying from sample to sample. It was observed that most of the DF food handlers did not wash their hands before serving (90.0%; n=18), as 50.0% (n=10) of the DF vending sites did not have water available for food handlers to wash their hands. Conclusion: It was observed that there was no evidence of monitoring of policies and procedures for all SF vending sites (100.0%; n=20) and for the majority (95.0%; n=19) of the DF sites. A high degree of composition is observed in the used frying oil samples. The results indicate high consistency (or repeatability) of used cooking or frying oil from the sampling points of WTA.Item Food safety practices, nutrition knowledge and menu adequacy at non-registered Early Childhood Development (ECD) centres in the Ntuzuma Area, Durban, South Africa(2023-05) Shabangu, Gugu Bongiwe; Grobbelaar, Heleen; Napier, Carin; Ijabadeniyi, Oluwatosin AdemolaGlobally, millions of children are deprived of their right to good nutrition which contributes to child development and nurturing while eliminating preventable diseases that could affect them at their early age. According to the World Health Organisation (WHO), food safety has become a health priority over the years with more than 95% of deaths reported globally due to diarrhoea and dehydration and 40% of these being young children. Food safety is the responsibility of every person who is involved in food handling. In general, food handlers’ mistakes include serving contaminated food, inadequate cooking, heating or reheating of food and allowing the consumption of food from unsafe sources. Children spend more than 50% of their day at an Early Childhood Development (ECD) centre therefore centres need to provide adequate meals and snacks in order to provide for the basic nutritional needs of these children. Nutrition remains an essential element of a child’s health care and nutrients are important for optimum growth, which is why regular small healthy meals for young children should include fruit and vegetables, whole grain and cereals, meat and meat alternatives (fish, legumes). The aim of this study was to investigate the food safety and hygiene practices, and evaluate the current nutrition knowledge of food handlers and also assess the nutritional adequacy of the menus at nonregistered ECD centres. This study also aimed to observe the food handling and hygiene practices of the food handlers and also determine the menu adequacy of meals served to the young children in these non-registered ECD centres. The designing of the research is one of the important steps in conducting a research as it helps structure research questions and objectives that have been outlined to provide a solution. This cross sectional study was of a quantitative nature and data was collected through structured research measuring tools that have been tested for their validity and reliability, and ensuring accuracy in measurements. A list of non-registered ECD centres (n=10) based in the Ntuzuma area was provided to the researcher by the Department of Social Development’s (DSD) Durban office. It must be stated that this list consisted of ECD centres that were not registered with DSD at the time of the study but were in the process of complying with the regulations and requirements stated by DSD, to assist in the sampling process. All ten of the centres were approached by the researcher and they all agreed to participate. Questionnaires and the observation checklist were then piloted in a sample group to establish suitability and adapted if necessary in one ECD centre while the remaining ECD centres formed part of the study (n=9). Eleven participants in total, two of whom were food handlers who assisted the managers when they were not available and nine who were both managers and food handlers formed part of the study. The researcher also conducted a plate waste study to determine the consumption patterns during meal times. Food finder version 2019 software was used to analyse the menu adequacy in each ECD centre by comparing it to the DRIs for children younger than five years old. Data collected from this study showed that food handlers were more knowledgeable on certain aspects of food safety as the majority of the food handlers knew that raw and cooked food needed to be placed separately during storage to prevent cross contamination. The vast majority of the centres had adequate space and utensils for cooking but insufficient chopping boards. Furthermore, simple hygiene practices such as washing of hands after a visit to the toilet and before food preparation were demonstrated by most of the food handlers. However, there was no antibacterial soap available for hand washing and no designated hand washing stations. Knowledge on temperature control was poorly demonstrated as all cooked foods should be kept very hot before serving; however, the food handlers kept their food warm by leaving it in pots on the stove with the lid tightly secured during the holding stage. The data gathered from this study was that food handlers at all the non-registered ECD centres needed to attend intensive formal training on food safety and hygiene practices on all the different aspects of food safety Nutrition knowledge questionnaire showed that majority of the FHs were able to correctly answer most of the questions relating to the South African Food Based Dietary Guidelines. However, it was disappointing that most of the food handlers were not aware that an average of 8 glasses of water a day are recommended to be drunk. The dietary analysis indicated that there was a low consumption of fruits and vegetables and dairy products as most meals lacked essential macro and micronutrients, contributing to the poor nutritional status of the young children. The microbial analysis revealed that the occurrence of Staphylococcus aureus and Escherichia coli was visible on the hands of the food handlers, the chopping boards and the preparation surface areas in each centre before washing but no growth was observed after washing, indicating that the cleaning process was effective. The overall observation assessment suggested that food safety compliance was not implemented. This indicates that thorough food safety and hygiene training is urgently needed. This study aimed to determine the food safety, hygiene practices and nutrition knowledge of all the food handlers, while analysing and assessing the nutrition adequacy of the menus offered to the children in these non-registered ECD centres, and lastly, to observe the food safety practices of food handlers and analyse the food workspaces for bacterial count. More research at non-registered ECD centres in other provinces is crucial in order to compare the results to the results obtained in this study. It is also recommended that other government stakeholders such as the Department of Social Development and the Department of Health be engaged in order to supplement existing knowledge and implement further practical improvements.Item Food hygiene and safety practices of food handlers in tuckshops at secondary schools in Umlazi(2019) Dlomo, Kaite Nokuthula; Napier, Carin E.; Ijabadeniyi, Oluwatosin Ademola; Vermeer, S. I.Objective: To determine the food safety and hygiene practices of the food handlers at secondary school tuck shops in Umlazi, Durban, South Africa in order to assess the risk of exposure to harmful bacteria that may cause food poisoning by conducting knowledge questionnaires and microbial tests from food handlers’ hands, counter surfaces and kitchen cloths. Research Methods: A total of 18 secondary schools, 48 food handlers and 24 managers were included in the study. The observational, descriptive and analytical study consisted of quantitative data collection methods. Quantitative data was obtained through a food hygiene and safety questionnaire designed for food handlers and tuck shop owners/managers, an observational checklist and microbial swab tests from food handlers’ hands, counter surfaces and kitchen cloths for analysis of microbial presence before preparation, during preparation and after preparation of food. The microbes tested for were Staphylococcus aureus, Escherichia coli, Salmonella, Listeria monocytogene, Aerobic spore formers and anaerobic spore formers. Data was captured in Excel and analyzed using a statistical package for social sciences (SPSS) version 24 for descriptive statisticsItem Food hygiene, safety, handling practices and knowledge of food handlers in a food retail company in Durban, KwaZulu-Natal, South Africa(2019) Sibisi, Anele Sinethemba; Napier, Carin E.The purpose of this study was to investigate the food hygiene, food safety, food handling practices and knowledge of Food Handlers in a food retail company in Durban, KwaZulu-Natal, South Africa in order to inform management on the knowledge of the Food Handlers in the company of the standards of food hygiene, food safety, and food handling practices. The objective was to determine and describe the knowledge of food hygiene and safety versus the standard of the observed food hygiene, safety and handling practices demonstrated by the Food Handlers in the particular establishments. Literature suggests that there is a direct correlation between knowledge and performance with regard to the food hygiene and safety standards that would exist in an establishment (Seaman 2010). This study attempted to draw a correlation between the managers/supervisors (Mngrs/Sups) knowledge and that of the Food Handlers (FHs) as it was of particular interest, in order to verify the assumptions made by other researchers with regard to management/supervisory knowledge being linked to the level of food knowledge and practices demonstrated by the Food Handlers (Medeiros, Cavalli, Salay, and Proenca 2011). The research was conducted in 20 food service establishments that belonged to the same food retail company in Durban, KwaZulu-Natal. This food retail company has about 150 stores which practice voluntary trading. The company has a very solid food safety policy which is made available to the owners of each establishment to implement and maintain. Quarterly food safety audits by an external company are carried out at each establishment and the results are shared with the owners in order to close any gaps that may exist. This research aims to provide data that will report on the food safety standards in each establishment as assumed by the company to be practised. The sample was randomly selected (all the names of the stores were put into a container and randomly selected) based on the establishment category i.e. mini market, super market and hyper store. Ethical approval was granted by the Institutional Research Ethics Committee at Durban University of Technology. The total sample for the study was 250 which was made up of 234 Food Handlers and 16 managers/supervisors. Information letters and consent forms were presented to and signed by the participants before data collection commenced. The study design was observational and descriptive by nature. To determine the food hygiene, food safety, food handling practices and knowledge of Food Handlers, two questionnaires were administered and an observation checklist was administered. All data collection was quantitative and all participation was voluntary. A permission letter was obtained from the company which was used to grant the researcher entry into the establishments but access was dependent on permission being given by the owners of the selected establishments. Data obtained from this questionnaire was captured on a Microsoft Excel® Spreadsheet and analysed for descriptive statistics using the Statistical Package for the Social Sciences (SPSS), version 24. The majority of the workforce was made up of females at both management and food handler level (75.0%; n=12 and 74.8%; n=175 respectively). The study group was predominately aged 30 years and older with the majority having grade 12 as the highest level of education. Noticeably, not all of the managers and FHs were trained upon appointment although the company has a solid food safety induction resource programme that is made available and distributed to each establishment. The food safety training module focuses on all aspects of food safety but since not all the respondents were trained on all the 12 modules, they displayed greater knowledge in selected areas and less in others; for instance, greater knowledge was shared about personal hygiene compared to record keeping, temperature recording and pest control, which are critical elements in ensuring food safety. To support this finding, unexpectedly 25.0% (n=4) of Mngrs/Sups and 47.0% (n=110) of the FHs stated that according to their knowledge thawing frozen food on the counter at room temperature was acceptable. This demonstrated that almost half of the FHs did not know that it is important to prevent bacteria present in food from multiplying in order to eliminate food poisoning. Additionally, the practice of thawing/defrosting food at room temperature was observed at most of the establishments but mostly at the Hyper stores. Furthermore, the vast majority of FHs knew that food should not be handled when they are suffering from any type of health problem, but 7.3% (n=17) stated that when they are suffering from the flu, and are coughing and sneezing, they are still permitted to handle food which assumes that it does not pose a risk to food safety whereas all the Mngrs/Sups knew that illness should not be permitted in the food production areas. Some FHs even stated that they would come to work sick otherwise they would not be paid. Almost all (n=15; 93.8%) of the Mngrs/Sups correctly stated that wiping cloths spread microorganisms but not all of the Mngrs/Sups knew that wiping cloths should be placed in a sanitizer bucket in-between use. This indicates a lack of knowledge with regard to food safety hazard preventative measures. Some of the FHs did not know that not all chemical cleaning products are graded as being effective in a food production/preparation environment and that general cleaning removes dirt only while sanitizing surfaces also kills bacteria. More than half of the FHs incorrectly stated that it was acceptable to leave mops and brushes in a bucket of dirty water in-between use which was an unacceptable practice prevalent in most of the establishments. The vast majority (93.8%; n=15 Mngrs/Sups, 93.2%; n=218 FHs) of the respondents agreed that food that has reached its expiry date should be thrown away but the researcher found during the observations that some of the establishments had expired stock that was being used in food preparation, and this was mostly evident at the Hyper stores (80.0%; n=4); however, at the Mini stores the expired stock was still on the shelves for sale. A shortage of utilities, resources and facilities in the various establishments was highlighted as a stumbling block to obtaining and achieving the desired food safety standards. Some establishments were under new ownership and were still establishing food safety structures. The outcomes of the study will be made available to the management of the food retail stores in the hope that the standards of food safety in each establishment will be improved as an unfortunate food incident will tarnish the brand image of the organization and not just the particular establishment.Item Evaluation of traditional South African leafy plants for their safety in human consumption(2007) Mudzwiri, Mashudu; Reddy, Lalini; Odhav, BhartiEighteen traditionally leafy vegetables consumed as food or medicinal compounds by a majority of people in the KwaZulu Natal province of South Africa were analysed for the presence of potentially harmful chemicals (antinutrients) and for their toxicity and mutagenicity. The purpose of the study was to determine whether leafy vegetables were safe for human consumption. Chemical analysis showed that none of the vegetables contained cyanogenic glycosides, however all the vegetables contained oxalic acid ranging from 24.1 mg/ml to 798.2 mg/ml with Solanum nigrum, Portulaca oleracea and Mormodica balsamina showing the highest concentrations. Most of the vegetables contained negligible amounts of phytic acid and saponins, except for Momordica balsamina (3.01 mg/ml and 1.83 mg/ml, respectively). Fourteen of the plants contained alkaloids with Portulaca oleracea having the highest content (1.53 g total alkaloids/5 g leaf material). Eight of the plants were found to inhibit trypsin activity. These chemical analyses were carried out in duplicate and the mean and standard deviation were used. The Ames test revealed that none of the leafy vegetables produced a mutagenic frequency above 1, except 10 000 µg/ml organic extract of Senna occidentalis (mutagenecity considered at mutagenic frequency above 2), thus none were considered mutagenic. All 18 organic extracts did not kill off more than 50% brine shrimp and were thus considered non-toxic. On the other hand the aqueous extracts of seven vegetables, namely, Physalis viscosa, Amaranthus dubius, Justicia flava, Bidens pilosa, Senna occidentalis, Chenopodium album and Ceratotheca triloba, killed more than 50% of the shrimp and are thus considered toxic above 100 µg/ml. The MTT assay carried out on the organic extracts indicated that 17 vegetables did not kill off more than 50% of HepG2 cells and were thus considered non-cytotoxic. The aqueous extracts of four vegetables, namely, Justicia flava, Asystasia gangetica, Momordica balsamin and Senna occidentalis, however killed more than 50% of the shrimp and were thus considered cytotoxic above 1 000 µg/ml. It may be concluded from the antinutrient analyses and the bioassays on the 18 vegetables that caution needs to be maintained with the consumption of certain leafy vegetables included in this study, especially Senna occidentalis.