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Item Open Access Empowerment model for people with disabilities participating in income generating activities: a case of a protective workshop in Bloemfontein(University of the Free State, 2018) Tinta, Nokuthula; Steyn, H. J. H.; Vermaas, J. F.𝑬𝒏𝒈𝒍𝒊𝒔𝒉 South Africa has 7,5% of people living with a disability. As a result, they experience difficulty in accessing education and employment opportunities. This high level of unemployment consequently results in people with disabilities working in sheltered employment which are offered by the State or by private welfare organisations and self- help programmes that are not sustainable in themselves. The aim of the study was to design an empowerment model that can enhance the participation of people with disabilities in income-generating activities. To achieve this aim, the study explored the experiences and perceptions of people with disabilities working in a protective workshop towards income-generating activities. The researcher used a qualitative approach to explore the experiences of people with disabilities participating in income-generating activities in one of the protective workshops in Bloemfontein. A total of 18 participants were recruited, using a purposive sampling approach. Both observations and semi- structured interview guides were used to generate more in‐depth interpretations from the participants. The content analysis which is based on turning the observations and data from the interviews into themes that can be used to gain insight into participants were applied. Findings indicated that the participants were involved in most popular informal income- generating activities such as beading, knitting, tapestry and sewing and that the majority had not attained adequate education and training to enable them to participate effectively in income-generating activities. Findings also indicated that the participants were mainly faced with attitudinal and institutional barriers, which have had an adverse influence on their performance. Despite the challenges that the participants were experiencing, the findings suggest that the participants also benefited in various ways from their involvement in the workshop. It is concluded that despite government schemes and programmes people with disabilities participating in still experience institutional, attitudinal and physical barriers as viewed by the social model. The main recommendations are that education and training to empower people with disabilities should start from pre-school to adulthood as it will raise perfection which will enhance effective task performance in the future as well as provision of more training programs and workshops that will empower people with various disabilities with vocational and life skills. People with disabilities participating in income-generating activities empowerment model could enhance the skills of people with disabilities. ___________________________________________________________________Item Open Access The effect of dietary omega-3 fatty acids with specific reference to Echium seed oil on pork quality(University of the Free State, 2019-01) Van Wyngaard, Barbara Elizabeth; Hugo, A.; Strydom, P. E.; Pohl-Albertyn, C. H.; De Witt, F. H.; Kanengoni, A.The objective of this study was to determine the effect of Echium seed oil, together with other n-3 containing oils, on the levels of long chain n-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA), eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) deposited in the animal tissue. Further, to determine the effect of these experimental diets on animal production and meat quality under commercial production conditions. The study also included the manufacturing of processed meat products from experimental animals and determining the chemical and sensory stability of such products. Sixty Landrace x Large White crossbred pigs, with an average weight of ± 30 kg, were randomly divided into five treatment groups. These treatments comprised of a control diet, supplemented with 1% palm oil (BergaFat HPL-160) and four experimental diets supplemented with one of 1% soya oil, 1% linseed oil, 1% fish oil and 1% Echium oil. Pigs were fed until the average live weight was ± 110 kg. Growth performance (weight increase, ADG and FCR) showed no significant differences between treatments. The only differences in carcass characteristics were the linseed treatment which demonstrated a smaller shoulder circumference and thinner backfat thickness compared to the other treatments. Backfat from the control had the best technological properties as it had lower levels of PUFA and a lower double bond index (DBI) compared to the other treatments. The Echium treatment had the highest levels of stearidonic acid (SDA) (mg/100g tissue) in the back-, belly fat and muscle. In all three these tissues the Echium treatment also had higher levels of EPA and DPA, however it was still significantly lower than the levels in the tissue of the fish oil treatment. In both the back- and belly fat, the Echium had no effect on the levels of DHA, however in the muscle it did increase the levels of DHA. The levels of EPA, DPA and DHA was the highest in the fish oil treatment, however the Echium treatment had significantly higher levels than the other treatments. There were no problems with lipid stability in either the fresh or frozen pork and values were far below the threshold value. A trained panel was unable to detect any sensory differences between the Echium treatment and the control. Processed meat products are more susceptible to lipid oxidation and increasing the levels of PUFA normally causes accelerated rancidity problems. In general pork bangers had very high TBARS and the Echium treatment had the highest values. The high TBARS values had a clear influence on the sensory properties as the bangers from the Echium treatment scored the lowest for taste, aftertaste and overall acceptability. Bacon did not have any problems with either the lipid stability or sensory properties, due to the anti-oxidative action of nitrite and the preservative effect of smoking. TBARS values for all treatments from the salami were all below the threshold value were rancidity could be detected. Under the US Food and Drug Administration guidelines the meat from Echium oil treatment in this study can be labelled as a source of EPA, DPA and DHA as it contributed more than 10% to the daily recommendation. Pork products (bangers, bacon and salami) manufactured from meat of the Echium treatment can be labelled an excellent source of total n-3 PUFA as they contribute 91.5, 34.08 and 41.1% respectively. Therefore, pork and pork products from animals fed Echium oil can be considered functional foods as it will have a positive effect on human health. South African pig producers may therefore consider using Echium oil to improve the healthiness of their pork and marketing it as a health food.Item Open Access Selection, extraction, characterization and application of mucilage from cactus pear (Opuntia ficus-indica and Opuntia robusta) cladodes(University of the Free State, 2016-08) Du Toit, Alba; De Wit, Maryna; Hugo, Arno; Fouché, HermanEnglish: Cactus pear plants (Opuntia ficus-indica and Opuntia robusta) are edible plants that grow and thrive in the semi-arid area of the Free State, South Africa, yet are unknown food sources. Cactus pear cladodes could be developed into a crop that could offer solutions in terms of food security, yet are ignored and underutilized in South Africa. Extensive research done abroad on the nutritional and therapeutic properties of cladodes and mucilage verified its high potential for human consumption. The development of mucilage into a commercial nutraceutical food product offers an opportunity to add value to the crop while providing a healthy product that could significantly enhance the well-being of the South African consumer. A successful, easy, inexpensive and chemical free extraction process was developed, yet cladodes were not equal in terms of the amount of quality of mucilage. Thus, the most appropriate cultivar for optimal mucilage yield and quality from forty-two local cultivars had to be selected and cladode harvesting time established. It was found that mucilage yield was not a consequence of cladode size or moisture content, but of cultivar and viscosity. Seven cultivars were selected that proved to have the lowest viscosity while commercially viable in South Africa (O. ficus-indica cultivars namely Algerian, Meyers, Morado, Ficus-Indica, Gymno-Carpo, Tormentosa, Turpin). The eighth cultivar represented a different species (O. robusta Robusta). Further morphological and rheological investigations revealed that the dormant stage (dormant months) would be the optimal harvesting time, while the selection of cultivars were narrowed down to four (O. ficus-indica Algerian, Morado, Gymno- Carpo and O. robusta Robusta). Mucilage (native and freeze-dried powders) from all cultivars showed non-Newtonian, pseudoplastic tendencies. Higher viscosity mucilage was time dependent, rheopectic and had yield stress tendencies. Fluctuations in temperature, pH, concentration and electrolytes influenced the mucilage viscosity that could affect product texture. In the analyses of the native mucilage, lower pH during summer was correlated to higher mucilage yields. The flow properties, water- and oil- related properties showed the high potential of mucilage powders as commercial nutraceutical product. The chemical analysis of freeze-dried mucilage powders showed high fibre and minerals, yet low fat and carbohydrates. Although the protein content was low, the presence of proteins was confirmed for the protein-lipid interaction necessary in the stabilization action of emulsions. The higher organic acids in summer concurred with the lower pH (as a consequence of CAM) that in turn affected the mucilage viscosity and yield. Mucilage was successfully applied to food products and is recommended for commercialization as a nutraceutical food product. In terms of cultivar selection, ‘Robusta’ had the highest contents of protein, total fats (beneficial fatty acids), starch, potassium and phosphorous, while ‘Algerian’ mucilage had the lowest energy and insoluble fibre, but highest calcium, iron and copper contents. ‘Gymno-Carpo’ had high linoleic acid, magnesium and manganese and good fat ratios. It is recommended that cladodes be harvested in the summer months, directly after the fruit had been harvested for optimal mucilage yield and quality. ‘Robusta’ emerged as the best cultivar for higher viscosity mucilage and Algerian for lower viscosity mucilage of the best quality. However, a careful selection of the most appropriate cultivar mucilage would be paramount for specific food applications.Item Open Access Evaluation of the antimicrobial effect and strength properties of polyester, polyester/cotton and cotton treated with Anolyte(University of the Free State, 2011) Vermaas, Jana F.; Steyn, H. J. H.; Hugo, C.English: Textile materials are usually treated with chemicals like sodium hypochlorite and high temperatures to ensure sterility. This poses two potential problems: (1) it has a negative effect on strength properties of the textile fabric; (2) the harmful chemicals are discarded into the environment. Therefore, better and safer methods need to be investigated. A process has been developed where electro-chemically activated water (Anolyte) is produced by an anode-cathode system and the process is described as a change of the molecular state of the water. After production, the Anolyte exists in a metastable state while containing many free radicals and a variety of molecules and a very high oxidation-reduction potential. It returns to a stable state after 48 hours and become inactive again and, therefore, it is not a threat to the environment when discarded after use. Anolyte has been shown to be an effective disinfection agent in other areas such as the food industry. The aim of this study was to determine if Anolyte could reduce E. coli and Staph. aureus on textiles to the same extent as sodium hypochlorite and be effective without implementing such high temperatures. The influence of the Anolyte on textile material should also be evaluated to ensure that it could be used without damaging textile materials more than the currently used disinfection agents. The antimicrobial effect of the Anolyte was determined by contaminating cotton, polyester and polyester/cotton fabric swatches with E. coli and Staph. aureus, respectively. Survival was determined after laundering with the respective wash liquors. AATCC Test Method 61- 2009 was used with the LaunderOmeter. Wash liquors included filtered water, phosphate reference detergent B, sodium hypochlorite and Anolyte. Temperatures were maintained at 24, 30 or 60°C. The cotton, polyester/cotton and polyester were laundered for 5, 10 or 20 cycles respectively for the evaluation of the influence on tensile strength and tearing strength. The tensile strength tests were conducted with the Instron Tensile Tester and ISO/SANS 13934-1:1999 test method. The tearing strength tests were conducted with the Elmendorf Tearing Strength tester as per ASTM Test Method D 1424 - 63. The results indicated that Anolyte destroyed all E. coli and Staph. aureus on all the fabrics regardless of the temperature. The effect of the other agents were enhanced by the increasing temperature, but after laundering at 60°C no survival was found as a result of the high temperature. The Anolyte did not influence the strength properties of the cotton, polyester and polyester/cotton fabrics to a larger extent than the detergent or sodium hypochlorite solution. An increase in maximum load required to break the fabric and displacement at maximum load was found for the cotton and polyester/cotton fabrics after laundering treatments, while a decrease was caused after laundering of the polyester fabric. A decrease in tearing strength of all the fabrics was found after laundering with the treatments. The Anolyte also did not affect the dimensional stability of the fabrics. It could be concluded that the Anolyte is a viable alternative to currently used sodium hypochlorite, while it is effective at low temperatures. The Anolyte do not affect the textile fabrics more negatively than the detergent and sodium hypochlorite combination, and could, therefore, be a successful alternative.Item Open Access The evaluation of catholyte treatment on the colour and tensile properties of dyed cotton, polyester and polyamide 6,6 fabrics(University of the Free State, 2015-01) Cronjé, Natasha; Steyn, H. J. H.English: Colour is one of the most significant factors in the appeal and marketability of textile products. Cotton, polyester and polyamide 6,6 are the most prominent groups of fibres used in the world. A Life Cycle Assessment done on textile products revealed that the area of greatest environmental impact is the consumer use phase, due to the laundering habits for the care of these products over its life span. With the development of electrochemically activated water (Catholyte) and some research done to suggest it might be an environmentally friendly alternative detergent for laundering; the environmental impact during the consumer phase can therefore be considerably scaled down. The influence of Catholyte on the colourfastness of textiles is, however, unknown. Thus it was the aim of this study to determine the influence of Catholyte on certain colourfastness properties of dyed cotton, polyester and polyamide 6,6 textile fabrics. The sulphur, direct, reactive and azoic dyed cotton, disperse dyed polyester and acid dyed polyamide 6,6 textile fabrics were laundered (AATCC 61) with Catholyte, detergent and filtered water at 40C and 60C for five, ten, twenty or fifty cycles respectively. Wash fastness and staining (AATCC Evaluation Procedure 6) were measured instrumentally with a Konika Minolta Spectrophotometer 2300d using illuminant 10 standard observer. Colourfastness to rubbing, dry and wet (AATCC 8), as well as tensile strength (SANS 1092) was also evaluated. The colorimetric data obtained was converted to Gray scale ratings (AATCC Evaluation Procedure 12). The results indicate that laundering with Catholyte caused slightly less Gray scale values as opposed to laundering with detergent, with regards to sulphur and direct black dyed cotton. Higher wash fastness was observed when reactive black and direct red dyed cotton samples were laundered with Catholyte, as opposed to laundering with detergent. When laundering disperse red dyed polyester, acid red dyed polyamide, azoic orange, reactive red, blue, violet and green dyed cotton, with both Catholyte and detergent indicated similar wash fastness results. Staining results indicate that laundering sulphur black, reactive black, red, blue and violet, azoic orange dyed cotton and acid red dyed polyamide with detergent resulted in less staining than laundering with Catholyte. Laundering direct black dyed cotton resulted in less staining when laundered with Catholyte, compared to laundering with detergent. Regardless of laundering the disperse red dyed polyester, direct red and reactive green dyed cotton with either Catholyte or detergent, similar staining results were observed. The influence of both Catholyte and detergent on the colourfastness to dry rubbing of sulphur black, direct black and reactive black and red, azoic orange dyed cotton and acid red dyed polyamide were similar. Laundering the disperse red dyed polyester and the direct red, reactive green and blue dyed cotton, resulted in slightly higher colourfastness to dry rubbing when laundered with detergent. Laundering the reactive violet dyed cotton with Catholyte resulted in better colourfastness to dry rubbing when compared to laundering with detergent. Laundering the direct black, reactive black, red, blue, violet and green, azoic orange dyed cotton, disperse red dyed polyester and acid red dyed polyamide with Catholyte and detergent resulted in similar colourfastness to wet rubbing. Laundering the sulphur black and direct red dyed cotton with detergent resulted in slightly less colourfastness to wet rubbing when compared to laundering with Catholyte. Laundering sulphur black, reactive black and violet, direct red and azoic orange dyed cotton with detergent, caused greater loss in tensile strength as opposed to laundering with Catholyte. Laundering the direct black and reactive red, blue and green dyed cotton, disperse red dyed polyester, acid red dyed polyamide with Catholyte, caused greater loss in tensile strength.Item Open Access Degumming Gonometa postica cocoons using environmentally conscious methods(University of the Free State, 2015-02) Van der Merwe, Ismari; Steyn, H. J. H.; Hugo, C.English: The trend in the textile industry is at present towards eco-friendly processes and minimising the adverse ecological effects of production. Silk degumming is a high resource-consuming process, as far as water and energy are concerned. It further is ecologically questionable, because of the high environmental impact of effluents. The development of an effective degumming process would mean saving water and energy, recovery of valuable by-products such as sericin peptides, and lower environmental impact of effluents. The aim of this study was to develop and evaluate environmentally conscious degumming methods that could discriminate between sericin and fibroin, without harming the fibroin. The methods used and evaluated as environmentally conscious methods were tested against Orvus paste and all the samples were exposed to the method at a constant temperature of 32°C and a period of 10 days. Results indicated that an increased degumming time resulted in a decrease in the silk fibroin average molecular weight. A clear band at 25 kDa appeared with all the methods, indicating that the light chains were separated from the heavy chains during degumming. The degumming weight loss ranged from 27 to 41% over a time period of 10 days. Two of the methods namely the combination Orvus paste and Eucalyptus oil and catholyte were more efficient than Orvus paste. The SEM micrographs showed no fibrillations. This indicated further that the degumming methods were successful; the sericin was removed without damage done to the surfaces of the fibres. The maximum load and displacement means of the fibres differed with the different degumming methods applied. The strongest fibres were obtained from the control method. The weakest fibres came from the Vermicompost method. The results demonstrated that the environmentally conscious methods allow efficient, low cost degumming of sericin.Item Open Access Anolyte as an alternative bleach for cotton fabrics(University of the Free State, 2015-01) Seiphetlheng, Kgalalelo; Steyn, H. J. H.English: Bleaches are used in the textile industry for brightening, whitening and cleaning fabrics. The two commonly used bleaches are hypochlorite and peroxide bleaches. Peroxide bleaches are used more often than chlorine bleaches in fabric finishing. Chlorine is a harsh chemical harmful to human health and may even destroy the cotton fibre if not monitored. It destroys the cellulose and that affects the quality of the bleached fabric. Large amounts of these bleaches are released into the environment through washing and they harm the environment and ozone layer. Hence, new and better ways of bleaching needs to be investigated. Electrochemically activated water (Anolyte) has been recently introduced to the food industries as a disinfecting agent. Disinfection with Anolyte has been successful and convenient because Anolyte is generated onsite by simple electrolysis of a dilute salt solution. The production of Anolyte requires lower production cost and hazards associated with handling, transportation and storage. Anolyte is stable and after 48 hours the solution become inactive water and can be discarded without causing harm to the environment. Although Anolyte has been successful in the food industry, extensive research has not been done to determine whether it can be used in the textile industry. The aim of this study was to investigate the effectiveness of Anolyte as a bleaching agent compared to the commonly used sodium hypochlorite. Distilled water was used as control. The efficacy of Anolyte was determined at 24°C 30°C, 40°C, 60°C and 80°C. The effect of Anolyte and sodium hypochlorite on bleached cotton, unbleached cotton, dyed cotton and stained cotton respectively were evaluated in terms of tensile strength, stiffness and whiteness. Further investigations were done on the effect of bleaching temperatures mentioned above and duration of exposure ranged from 9 minutes, 18 minutes, 30 minutes, 45 minutes, 60 minutes, 90 minutes and 120 minutes. The study was an experimental research where bleaching of samples was done according to AATCC Test Method 61- 2009 carried out in the Launder-Ometer. Reactive red dyed cotton, vat blue dyed cotton, bleached cotton and unbleached cotton were laundered for 5, 10 or 20 cycles respectively for the evaluation of the influence on tensile strength, stiffness and colour change. The tensile strength tests were conducted with the Instron Tensile Tester and ISO/SANS 13934-1:1999 test method. The stiffness test ASTM D1388 – 08 the Cantilever principle was used. While AATCC test method 135-1985 for instructional colour measurement of textiles was used in determining colour change. 169 The results gathered from the study indicated that Anolyte was less effective than sodium hypochlorite as a stain remover for blood, tea, soot/mineral oil and blackcurrant juice. Anolyte caused more colour loss on coloured materials than sodium hypochlorite especially at high temperatures. Anolyte was less effective in bleaching unbleached cotton than sodium hypochlorite but without harming the tensile strength of the cotton. Although Anolyte caused dyed cotton to lose colour, the stiffness of the dyed cotton was less than that bleached with sodium hypochlorite, making the cotton fabric to be much softer and desirable. It was also gathered that sodium hypochlorite reduced the tensile strength of vat blue dyed cotton and bleached cotton more than Anolyte. However, Anolyte on the other hand reduced the tensile strength of reactive red dyed cotton more than sodium hypochlorite.