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THE EVALUATION OF ELECTRO-CHEMICALLY ACTIVATED WATER AS AN ALTERNATIVE DETERGENT FOR POLYAMIDE AND MACHINE WASHABLE WOOLvan Heerden, Natasha 17 October 2011 (has links)
The electro-chemical activation of aqueous media is relatively new technology.
The alkaline part of the activated media (catholyte) is used in a wide variety of
applications due to outstanding detergency properties. The standard
phosphate based detergents currently used by consumers cause a negative
impact on the environment. Catholyte provides an environmental friendlier
alternative as it returns to be neutral water within 48 hours after activation.
Although catholyte may be an environmentally friendly medium for washing,
the influence that it has on the properties of textile materials, for example wool
and polyamide is still only based upon speculation. Little is also known about
the soil removal efficiency of this medium on wool and polyamide.
The aim of this study was to evaluate electro-chemically activated water
(catholyte) as an alternative detergent for machine washable wool and
polyamide 6,6. This was done by determining the influence of catholyte on
certain important properties of these textile fabrics as well as the soil removal
efficiency.
The machine washable wool and polyamide 6,6 textile fabrics were laundered
at 30°C and 40°C with catholyte, phosphate detergent or distilled water for five,
ten, twenty or fifty laundering cycles respectively.
The standard test methods for laundering (AATCC 61) and measuring the
tearing strength (ASTM D1424), tensile strength (ISO/SANS 13934-1), wrinkle
recovery (AATCC 66), bending length (BS 3356), soil removal (AATCC 135) and
dimensional change were used. Analysis of variance (ANOVA) was used for the
statistical interpretation of the results obtained. Catholyte, detergent and distilled water caused a significant decrease in the
tearing strength of both the polyamide 6,6 and wool fabrics. The temperature
had no significant influence on the tearing strength of polyamide 6,6 fabric
although it caused a significant decrease in the tearing strength of wool. The
number of laundering cycles caused a significant decrease in the tearing
strength of the warp yarns of polyamide 6,6 as well as the weft and warp yarns
of wool, however it did not have a significant influence on the weft yarns of
polyamide 6,6.
Catholyte, detergent and distilled water as well as the temperature and number
of laundering cycles did not have a significant influence on the tensile strength
on the weft yarns of the polyamide 6,6. It did however cause a significant
decrease in tensile strength of the warp yarns of polyamide 6,6 and the weft
and warp yarns of wool.
Catholyte, detergent and distilled water as well as the temperature and number
of laundering cycles had a significant influence on the bending length
(stiffness) of polyamide 6,6 and wool, causing the fabric to become stiffer.
Catholyte, detergent and distilled water caused a significant increase in the
wrinkle recovery in the weft of polyamide 6,6 and decrease in wrinkle recovery
in the weft of wool. It did not have a significant influence in the warp of wool
and polyamide 6,6. The temperature had no significant influence on the
wrinkle recovery of the wool and weft of polyamide, although it caused a
significant fluctuation in the warp of polyamide 6,6. The number of laundering
cycles caused a significant fluctuation in the wrinkle recovery of the polyamide
6,6 and wool fabrics.
Catholyte, detergent and distilled water, as well as the temperature and
number of laundering cycles did not have a significant influence on the dimensional stability of polyamide 6,6. It did however cause the wool fabric to
shrink significantly.
Catholyte and detergent proved to be significantly effective in removing soil
from polyamide 6,6 and wool. The temperature only had a significant influence
on soil removal from the wool.
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THE WATER, ENERGY AND SOIL REMOVAL EFFICIENCY OF A TOP AND A FRONT LOADER WASHING MACHINESeiphetlheng, Kgalalelo 16 August 2012 (has links)
Water and energy are used in the domestic laundering processes for optimum soil and stain
removal. Water and energy conservation are important issues in the quest for more environment friendly household practices. Washing machines have been invented as
household gadgets making laundry easier and faster. Common types of washing machine
include top loaders, front loaders and twin tubs. Literature indicate that top loaders use less
electricity but more water and front loaders use less water but more electricity. However
efficient soil removal is the main concern of the consumer.
The purpose of the study was to determine water, energy and soil removal efficiency of a top
loader and a front loader washing machine. A quantitative research strategy was used and
controlled experiments were conducted in order to attain accurate data. An 8.0 kg capacity
top loader and an 8.5 kg capacity front loader of the same manufacturer were purchased.
The âdaily wash programâ and the âquick wash programâ of both machines were selected as
wash programs for the project. Cold wash (water at room temperature) was used for the top
loader and cold wash, 30 °C, 40 °C and 60 °C for the front loader. A 5kg load of 3 samples
of C-09 cotton (soiled with pigment oil, purchased from CFT) and cotton filler cloths were
used for each wash cycle and each cycle repeated three times. The efficiency of the
machines and programs to remove stains were tested on the following stains: CS-103 red
wine, CS-12 blackcurrant, CS-BC-03 tea, C-BC-02 coffee, CS-28 rice starch, CS-26 corn
starch, CS-6 dressing, CS-73 locust bean gum, CS-54 oatmeal/chocolate, CS-38 egg
yolk/pigment, CS-01 blood, C-05 blood/milk/ink, CS-08 grass, CS-02 cocoa, C-10
pigment/oil/milk, C-02 olive oil/soot, CS-32 sebum bey, CS-17 make-up and CS-216 lipstick.
60g Non phosphate ECE reference detergent without optical brightener was used.
Redeposition of soil was determined on CN-11 white cotton.
The drained water was collected and measured in litres. The energy consumption was
measured in watt-hour in every program. Soil removal was measured with a colorimeter in
CIE L*a*b* colour scale (AATCC test method 61-2010) and an analysis of variance was
used to aid in the interpretation of the data. The results of the study indicate that, the top
loader used more water than the front loader. The daily wash used more water than the
quick wash in both the top loader and front loader. The front loader used more energy than the top loader at cold wash. More energy was used in the daily wash than quick wash of the
front loader. It was also evident that the daily wash program in both machines was more
efficient in soil and stain removal than the quick wash. At cold wash the daily wash was more
efficient in soil and stain removal than the quick wash program but at 60 °C there was no
difference in the rate of stain removal in both the quick and daily wash programs. The best
soil and stain removal was observed at 60 °C in both the quick and daily programs. The top
loader machine used more water, less energy and removed less soil and stain. It was also
evident that, the front loader washing machine is more efficient in soil and stain removal and
it uses less water but it uses more energy than the top loader machine.
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EVALUATION OF THE ANTIMICROBIAL EFFECT AND STRENGTH PROPERTIES OF POLYESTER, POLYESTER/COTTON AND COTTON TREATED WITH ANOLYTEVermaas, Jana F 16 August 2012 (has links)
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.
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Professional socialisation of family ecology and consumer science students at South African UniversitiesCornelissen, Judith Jean 03 1900 (has links)
Thesis(PhD)--University of Stellenbosch, 2006. / Professional socialisation can be described as a subconscious process whereby persons
internalise behavioural norms and standards and form a sense of identity and commitment
to a professional field. The primary goal of professional socialisation is considered to be
internalisation of the professional culture and the development of a professional identity. It
is learned through interaction with professionals and educators during a student’s
education. It is a continuous, life-long process of learning formal knowledge, skills and
rules, as well as informal and tacit knowledge, norms, values and loyalties within the
profession. An understanding of the professional socialisation process is vital to all persons
involved in postsecondary education, for it is the professional socialisation process that
allows education to achieve its goals.
This dissertation determined whether students of Family Ecology and Consumer Sciences
in South Africa are professionally socialised into developing a professional identity within
the Family Ecology and Consumer Sciences profession. The objectives of the research
included; to examine through a literature review the development of the profession and to
propose a new position for the profession in South Africa; to identify the factors that
influenced South African students when they decided on Family Ecology and Consumer
Science as a field of study and the factors that influenced them while they were obtaining
their degree at a South African university; to determine whether Family Ecology and
Consumer Science students evidence the developmental stages of the Cohen model of the
professional socialisation process; to determine Family Ecology and Consumer Science
professionals’ perceptions of their professional preparation environments; and to analyse
and compare Family Ecology and Consumer Science programmes at South African
universities.
A quantitative research methodology in the form of an analytical survey was undertaken
with the participation of students and staff at South African universities where Family
Ecology and Consumer Science programmes are offered by means of postal questionnaires. Three questionnaires were used in the research, namely; the Professional Socialisation
Influences (PSI) questionnaire; the Professional Socialisation Staging Scale (PS3)
questionnaire; and the Emphases, Process and Influences on the Professional Preparation
Programmes questionnaire. A conceptual framework was used to compare the Family
Ecology and Consumer Science professional preparation programmes presented at South
African universities..
Descriptive statistics and the factor analysis method were used to examine the objectives to
determine which factors influenced students to select Family Ecology and Consumer
Sciences and the factors that influenced them while they were studying for a degree at a
South African university. Descriptive statistics, ANOVA and Bonferroni Post-Hoc tests
were used to examine whether Family Ecology and Consumer Science students evidenced
the developmental stages of the Cohen model of the professional socialisation process.
Descriptive statistics were used to examine Family Ecology and Consumer Science
professionals’ perceptions of their professional preparation environments.
The main findings drawn from the study indicated that Family Ecology and Consumer
Sciences students, when selecting Family Ecology and Consumer Science as a profession,
were influenced by the ‘Service Ideal’ and ‘Entrepreneurial’ factors. Aspects that elicited
the highest percentage of positive responses from the respondents were; ‘desire to help
others’; ‘a desire to improve the quality of family living’; ‘a desire to help people learn to
do things’; and ‘entrepreneurial possibilities of the course’.
While studying for a degree in Family Ecology and Consumer Science, they were
influenced by the factors ‘Student Interaction’ and ‘Departmental Influences’. Aspects such
as; ‘career opportunities available’; ‘application of what I learned to my personal life’; and
‘employment opportunities available’; were those that had the biggest influence.
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Die versoenbaarheid van katoen/nylon- en katoen/poliester- skeringgebreide terriestofhanddoeke met industriele versorgingsproseduresDe Bruin, Riette 10 1900 (has links)
Thesis (MVerbruikerswet)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: The aim of the study was to investigate the compatibility of cotton/nylon and cotton/polyester warpknit
terry towelling fabrics with industrial laundering procedures. The literature review focused, on
the one hand, on the manufacture, finishing and structure of warp-knit terry towelling fabrics as well
as on the physical structure, chemical nature and characteristics of the textile fibres used in the
manufacturing of the towelling. On the other hand, a full exposition of the industrial laundering
processes is provided, with specific reference to aspects that can have an effect on the towelling
fabrics during the wash and tumble-drying cycles.
Chapters Three and Four are reports on two research projects that can each be read
independently. The aim of the first project was to determine the effect of industrial laundering
procedures on the durability of cotton warp-knit terry towelling fabrics with a synthetic base
structure. The tensile strength of cotton warp-knit terry towelling samples with a synthetic base
structure was determined in the warp and weft directions and after 10, 20, 30, 40, and 50 wash
cycles as well as wash and tumble-drying cycles. The tensile strengths in the warp direction of the
washed terry towelling samples decreased significantly (p < 0.001) after 50 wash cycles. In
contrast to this, the tensile strength in the weft direction increased, although not significantly
(p > 0.05). As far as the comparison of the effect of industrial wash and wash and tumble-drying
cycles is concerned, the tensile strengths in the warp direction of the towelling samples that were
washed and washed/tumble-dried, were significantly lower (p < 0.001) after 20 and after 50
laundering cycles. As far as the tensile strengths in the weft direction were concerned, a similar
pattern as with the wash and wash/tumble-drying processes, occurred. The tensile strengths
initially increased and then gradually decreased. Furthermore, the tumble-drying process had
greater damaging effects after 40 laundering cycles (p = 0.043) and especially after 50 laundering
cycles (p < 0.0001).
The aim of the second research project was to compare the durability of cotton warp-knit terry
towelling fabrics with a nylon base structure with cotton warp-knit terry towelling fabrics with a
polyester base structure after they had been subjected to industrial laundering processes. It was
first established whether cotton/nylon and cotton/polyester warp-knit terry towelling fabrics are
comparable. Secondly, the durability of cotton/nylon and cotton/polyester terry towelling fabrics
was compared by determining the tensile strengths of the samples in the warp direction after they
have been subjected to 50 industrial wash as well as wash and tumble-drying cycles. The two
groups of untreated samples were regarded as similar on the basis of the percentage of fibre
composition, knit fabric structure, knit density, mass and tensile strength. After 50 industrial wash
cycles the tensile strengths of the cotton/nylon and cotton/polyester warp-knit terry towelling
samples decreased significantly (p < 0.05). But there was no significant difference (p > 0.05) between the tensile strengths of the cotton/nylon and the cotton/polyester terry towelling samples
after 50 washing cycles. There was a highly significant difference (p < 0.001) between the tensile
strengths of the cotton/nylon and the cotton/polyester terry towelling samples after 50 wash and
tumble-drying cycles. The tensile strength of the cotton/polyester terry towelling samples remained
practically unchanged after the 50 wash/tumble-drying cycles, with the tensile strength of the
cotton/nylon terry towelling samples decreased significantly (p < 0.001). / AFRIKAANSE OPSOMMING: Die doel van die studie was om ondersoek in te stel na die versoenbaarheid van katoen/nylon- en
katoen/poliëster- skeringgebreide terriestofhanddoeke met industriële versorgingsprosedures. In
die literatuuroorsig is daar enersyds gefokus op die vervaardiging, afwerking en struktuur van
skeringgebreide terriehanddoekstowwe asook op die fisiese struktuur, chemiese aard en
eienskappe van die tekstielvesels waarvan die handdoeke vervaardig is. Andersyds is ’n volledige
uiteensetting van industriële versorgingsprosedures gegee, met spesifieke verwysing na aspekte
wat tydens die was- en tuimeldrogingsiklusse ’n uitwerking op die handdoekstowwe kan hê.
Hoofstukke drie en vier is opgeskryf as twee navorsingsprojekte wat elk ‘n geheel vorm. Die doel
van die eerste projek was om die effek van industriële versorgingsprosedures op die
duursaamheid van katoen skeringgebreide terriestofhanddoeke met ‘n sintetiese basisstruktuur te
bepaal. Die breeksterkte van katoen skeringgebreide terriestofmonsters met ’n sintetiese
basisstruktuur is in die skering- en inslagrigtings tydens en na afloop van 10, 20, 30, 40, en 50
was- asook was- en tuimeldrogingsiklusse bepaal. Die breeksterktes in die skeringrigting van die
gewaste terriestofmonsters het betekenisvol afgeneem (p < 0.001) na 50 wassiklusse. In
teenstelling hiermee het die breeksterktes in die inslagrigting toegeneem, hoewel nie betekenisvol
nie (p > 0.05). Wat die vergelyking van die effek van industriële was- en was en
tuimeldrogingsiklusse betref, is die breeksterktes in die skeringrigting van die handdoekmonsters
wat gewas en gewas/getuimeldroog is, beduidend laer (p < 0.001) na 20 en na 50
versorgingsiklusse. Wat die breeksterktes in die inslagrigting betref het ‘n soortgelyke patroon by
die was- en was/tuimeldrogingprosesse voorgekom. Die breeksterktes neem aanvanklik toe en
daarna geleidelik af. Verder het die tuimeldrogingsproses na 40 versorgingsiklusse (p = 0.043) en
veral na 50 versorgingsiklusse (p < 0.0001) ’n groter skadelike effek getoon.
Die doel van die tweede navorsingsprojek was om die duursaamheid van katoen skeringgebreide
terriestowwe met ’n nylon basisstruktuur te vergelyk met katoen skeringgebreide terriestowwe met
’n poliëster basisstruktuur nadat dit aan industriële versorgingsprosedures blootgestel is. Daar is
eerstens vasgestel of katoen/nylon en katoen/poliëster terriehanddoekstowwe vergelykbaar is.
Tweedens is die duursaamheid van katoen/nylon en katoen/poliëster terriestowwe vergelyk deur
die breeksterktes van die monsters in die skeringrigting te bepaal nadat dit aan 50 industriële wasasook
was- en tuimeldrogingsiklusse blootgestel is. Die twee groepe onbehandelde monsters is
as soortgelyk beskou op grond van die persentasie veselsamestelling, breistofstruktuur,
breidigtheid, massa en breeksterkte. Na 50 industriële wassiklusse het die breeksterktes van die
katoen/nylon en katoen/poliëster skeringgebreide terriestofmonsters betekenisvol (p < 0.05)
afgeneem. Daar was egter nie ’n betekenisvolle verskil (p > 0.05) tussen die breeksterktes van die katoen/nylon en katoen/poliëster terriestofmonsters na 50 wassiklusse nie. Daar was ’n hoogs
betekenisvolle verskil (p < 0.001) tussen die breeksterktes van die katoen/nylon en
katoen/poliëster terriestofmonsters na die 50 was/tuimeldrogingsiklusse. Die breeksterkte van die
katoen/poliëster terriestofmonsters het na die 50 was/tuimeldrogingsiklusse feitlik onveranderd
gebly terwyl die breeksterkte van die katoen/nylon terriestofmonsters hoogs betekenisvol
(p < 0.001) afgeneem het.
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The development and evaluation of measurements on spaghetti with diverse quality characteristicsMacGregor, Elizabeth 04 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Pasta manufacturing is a process whereby wheat flour is converted into a shelf-stable food that is
more desirable than native wheat flour. It can be fortified and may serve as a valuable source of
nutrition in developing countries. Quality measures are of importance in the production process to
ensure a consistent and acceptable finished product.
Literature provides information on many aspects of wheat types, milling techniques and processing
of pasta. Protein content and quality of cultivated wheat varieties is of major importance to
produce quality pasta products. Wheat types of lower protein content are more readily available
than traditionally used durum wheat. As in all food products, the cost of final products is of major
importance. Bread wheat is generally less expensive than durum wheat. However, product quality
(and thus acceptability) may be lower. Direct measurements of product quality are currently limited
to protein content, moisture content, colour analyses and certain other characteristics measurable
in a laboratory, for example mechanical strength and firmness. Direct measurements of defects
that may affect final product quality, such as cracks and fissures on the strands of spaghetti,
different types of spots and lines on the strands, broken units, units sticking together and odd
shapes are not well documented.
During the first part of this study, spaghetti quality evaluation techniques were reviewed, improved
or developed and thereafter standardised. This developmental research was conducted to
establish valid and reliable measures (with a high degree of repeatability) for the evaluation of dry
and cooked pasta quality characteristics. A wide variety of available products on the South African
market were evaluated for different quality characteristics. From this evaluation standards were
drawn up, tested for validity and reliability by means of repeatability. Minimum sample sizes for the
evaluation of different quality characteristics were calculated and presented in the study, together
with reference photographs that can be used to evaluate spaghetti. This study found that colour evaluation by means of commercially available apparatus needs
revision. This study suggests the use of multiple layers when evaluating translucent food products
for colour. The occurrence of fissures and flour spots are of importance for the quality of the final
product. This study provides a set of valid and reliable measurements for measuring the quality of
dry and cooked spaghetti. Simple techniques can therefore be used to detect the presence or
absence of these defects.
Thereafter an empirical study was conducted to describe the differences between spaghetti
prepared from durum and non-durum wheat, dried at different temperatures and at different relative
humidity. Spaghetti samples of diverse perceived quality, from different manufacturers, were
purchased and evaluated. Standard methods and the newly developed testing methods were used
to test whether these methods effectively distinguish between spaghetti of diverse quality,
reflecting on the validity of the methods. Correlations were calculated between dependent and
independent variables in an attempt to find possible explanations for certain defects or quality
differences, and to test certain theories in the literature.
Certain relationships between quality characteristics were found, while others were questioned.
The most important proven relationships were between protein content and its effects on reducing
quality defects such as fissures, breakages and cooking losses. The relationship between ash
content and spaghetti colour could not be confirmed in this study. This study confirmed that
protein remains one of the most important variables to ensure consistent quality spaghetti. / AFRIKAANSE OPSOMMING: Pastavervaardiging is ‘n proses waartydens koring meel omskep word in a produk met ‘n stabiele
en lang rakleeftyd wat meer gewens is as die oorspronklike koring meel. Pasta kan gefortifiseer
word and kan dien as a waardevolle voedingsbron in ontwikkelende lande. Om ‘n konstante en
aanvaarbaare finale produk te verseker is kwaliteitmetings gedurende die produksie proses
belangrik.
Die literatuur voorsien heelwat inligting rakende aspekte van belang vir pastakwaliteit, byvoorbeeld
koringtipes, maaltegnieke en die vervaardigingsproses. Proteïninhoud en die kwaliteit daarvan is
van groot belang tydens die produksie van hoë kwaliteit pasta. Koringtipes met ‘n laer
proteïninhoud is meer geredelik beskikbaar as tradisionele durumkoring. Soos met alle
voedselprodukte, is die koste van die finale produk van groot belang. Oor die algemeen verhandel
broodkoring teen laer pryse as durumkoring. Die produkkwaliteit en aanvaarbaarheid van pasta
vervaardig van broodkoring kan egter laer wees as dié van durumkoring. Direkte metings van
produkkwalitiet is tans beperk tot proteïninhoud, voginhoud, kleuranalise en sekere eienskappe
meetbaar in ‘n laboratorium, byvoorbeeld meganiese sterkte en fermheid. Die direkte meting van
defekte wat finale produkkwaliteit kan beïnvloed, byvoorbeeld barste, krake, meel kolletjies, strepe
op spaghetti-eenhede, gebreekte eenhede, eenhede wat aan mekaar kleef en ongewone vorms, is
nie goed gedokumenteer nie.
Gedurende die eerste gedeelte van hierdie studie, is ‘n oorsig van spaghetti evaluasie tegnieke
beskikbaar in die literatuur gdoen, waarna sekeres verbeter is, ander ontwikkel is en finaal
gestandariseer is. Hierdie navorsing is uitgevoer om geldige en betroubare metings (met ‘n hoë
graad van herhaalbaarheid) vir die evaluasie van droë- en gaar pastakwalitietseienskappe vas te
stel. ‘n Wye verskeidenheid van produkte beskikbaar op die Suid-Afrikaanse mark is ge-evalueer
ten opsigte van verskillende kwaliteitseienskappe. Vanuit hierdie evaluasies is standaarde
saamgestel en getoets vir geldigheid en betroubaarheid deur middel van herhaalbaarheid. ‘n
Minimum steekproefgrootte per kwaliteitseienskap is bereken en word vermeld in hierdie studie.
Daarmeesaam word verwysingsfoto’s aangebied wat gebruik kan word tydens die evaluasie van spaghetti. Hierdie studie bied a stel geldige en betroubare meting vir die kwaliteit van droe en
gaan spaghetti. Eenvoudige tegnieke kan dus gebruik word om die voorkoms van hierdie defekte
te meet.
Met afloop van die verkennende studie, is ‘n empiriese studie gedoen om die verskille te beskryf
tussen pasta vervaardig van durum en brood koring, gedroog teen verskillende temperature en
relatiewe humiditeit. Spaghettimonsters met oënskynlike diverse kwaliteit, vervaardig deur
verskillende maatskappye, is aangekoop en ge-evalueer. Standaardmetings en nuutontwerpte
metings is gebruik om te bevestig of die metings kan onderskei tussen spaghetti met
uiteenlopende kwaliteit, wat reflekteer op die geldigheid van die metingsmetodes. Korrelasies is
bereken tussen afhanklike en onafhanklike veranderlikes in ‘n poging om moontlike verklarings vir
sekere defekte of kwaliteitsverskille te vind, en ook om sekere teoriëe in die literatuur te toets.
Die verband tussen sekere kwaliteitseienskappe is bevestig en bewys, terwyl ander bevraagteken
was. Die mees belangrike verband was proteïninhoud en die effek daarvan om die voorkoms van
defekte, soos barste, gebreekte eenhede en kookverliese te verlaag. Die verband tussen
asinhoud en spaghettikleur kon nie in hierdie studie bevestig word nie.
Hierdie studie het bevestig dat proteïn die mees belangrike veranderlike is wat oorweeg moet word
wanneer ‘n konstante hoë kwaliteit spaghettiproduk vervaardig word. Kleurevaluasie met behulp
van kommersieel-beskikbare apparaat vereis hersiening. Hierdie studie stel voor dat tydens kleur
evaluasie van voedsel wat lig deurlaatbaar is, dit in veelvoudige lae evalueer moet word. Die
voorkoms van defekte soos barste, krake of meel kolletjies is van belang ten opsigte van finale
produkkwaliteit. Hierdie studie bied riglyne vir die evaluasie van die genoemde defekte. Die
voorkoms van hierdie defekte is van groter belang as die graad waarteen die defek voorkom.
Eenvoudige tegnieke kan vervolgens gebruik word om die teenwoordigheid of afwesigheid van
hierdie defekte te bepaal.
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Meat quality of raw and processed guinea fowl (Numeda meleagris)Tlhong, Tumelo Maud 12 1900 (has links)
Thesis (MSc (Consumer Science)--Stellenbosch University, 2008. / The purpose of this study was to investigate the chemical composition mineral and cholesterol
content of the different cuts (breast, drumstick and thigh) of raw guinea fowl meat. The study
also aimed at establishing the effect of cooking method on guinea fowl quality attributes by
investigating the effect of different cooking methods on the chemical composition and sensory
attributes of the different cuts. The effect of injecting a brine solution on the chemical
composition and sensory attributes were also investigated.
There were no differences in terms of moisture content of the various cuts raw guinea fowl meat
The breast had significantly higher protein content when compared to drumstick and thigh
(P<0.05). The fat content was similar for all the cuts (P>0.05). Whilst the drumstick had
significantly the lowest value for ash content when compared to the thigh. Saturated fatty acids
(SFAs) and total unsaturated fatty acids (TUFAs) were not different (P>0.05) in all the cuts.
Drumstick had significantly higher monounsaturated fatty acids compared to other cuts (P<0.05),
and it had the highest polyunsaturated fatty acids (P<0.05). The breast had the lowest (P<0.05)
n-6 fatty acid value (44.25) and had relatively the lowest Polyunsaturated:Saturated (P:S) fatty
acid ratio of 1.74 when compared to the other cuts. High n-6:n-3 ratios, ranging from 7.05 to
16.58, were also found in all the cuts. Cholesterol was lowest (P<0.05) in the breast. Seventeen
amino acids were found, including the eight of the nine essential amino acids. Significant
differences were found in amino acid values for the different cuts. Values of iron were
significantly higher in the drumstick and thigh cuts (P<0.05), whilst drumstick had the highest
zinc content of all the cuts (P<0.05).
On investigating the effect of three cooking methods (baking-bag, foil-wrap, open-roasting at
140ºC for 65 minutes) on the chemical composition, the open-roasting method produced higher
moisture content (P<0.05) consistently for all cuts, with the breast having the highest and the
drumstick the lowest (P<0.05). The moisture content of the baking-bag method on the other
hand was consistently the lowest (P>0.05). This effect was significant for the breast, which had
lost the most moisture (P<0.05). The baking-bag method consistently resulted in a higher protein
content, which is attributed to the higher moisture loss (P<0.05) in comparison with the other
methods, resulting in a more concentrated product. With regard to the fat content no effect
resulting from the cooking methods could be observed (P>0.05), but the cuts’ natural fat content
was reflected especially in the open–roasting method (P<0.05) giving further support to the understanding that the open-roasting method indeed made the least inroads on the chemical
composition of guinea fowl meat under these restraints: controlled for cooking time and
temperature, internal temperature not controlled.
All the cuts cooked according to all the methods, had the favourable >0.4
Polyunsaturated:Saturated fatty acids (P:S) ratio, ranging from 0.91 to 1.42 between cuts and
treatments. The n-6:n-3 ratio was below the recommended beneficial value, namely <4:1, in all
the cuts irrespective of all the cooking methods, ranging from 2.47 to 3.08.
The study of the effect of the three cooking methods (baking-bag, foil-wrap and open-roast) on
the sensory attributes of the breast meat revealed that aroma-intensity of the three cooking
treatments did not differ significantly (P>0.05). Foil-wrap produced a more tender and juicier
product (P<0.05), while, when using the baking-bag method, values for flavour decreased
(P<0.05). It is proposed that a higher internal temperature (which was not controlled) was
attained when using the baking-bag method (temperature and time controlled) resulting in loss
of volatile flavour components.
The effect of the three cooking methods (baking-bag, foil-wrap and open-roast) on the proximate
composition (moisture, protein, fat and ash) of raw and cooked breast meat was investigated. As
anticipated raw breast meat had higher moisture content (74.55%, P<0.05) than the cooked
cuts, with open-roasting showing the highest (68.55%) value and foil-wrap close second
(68.12%). These values differed significantly from the baking-bag method (66.06%, P<0.05).
An investigation on the effect of brine infusion on the sensory attributes and chemical
composition (proximate and fatty acid composition, and mineral content) of breast meat, baked
in foil-wrap, was carried out using descriptive sensory analysis with the injected breast and the
control as variable. There were no significant differences (P>0.05) between the injected and the
control samples for any of the sensory attributes of aroma, tenderness, initial juiciness,
sustained juiciness and flavour. Judge:treatment variations were observed for all the attributes,
and samples differed for all attributes except for aroma. It is proposed that the use of the hand
injector could not effectively distribute the brine solution, hence the recommendation to repeat
the experiment using an electronic multineedle-injector. No effect was observed for the
proximate composition (P>0.05). Further research pertaining to cooking methods of meat of
free-range guinea fowl is recommended to address certain issues that have been highlighted.
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HIGH SCHOOL STUDENTS' PERCEPTIONS OF FAMILY AND CONSUMER SCIENCES EDUCATION AS A CAREER IN THE JACKSON PURCHASE DISTRICT OF KENTUCKYRattray, Stacey Michelle 01 May 2010 (has links)
The purpose of the study was to investigate why high school junior and senior students in the Jackson Purchase district of Kentucky choose to go or not to go into the profession of teaching Family and Consumer Sciences. The participants of the study were Family and Consumer Sciences teachers and junior and senior high school students enrolled in their classes. This study used a quantitative mode of inquiry. More specifically, two questionnaire instruments were developed and administered to participating teachers and students to answer the research questions. The questionnaire gathered data on the subject's perceptions of Family and Consumer Sciences education. In addition, demographics were derived from student participants. The study determined that students were predominantly college bound, mostly Caucasian, seniors, and female. The majority of students thought Family and Consumer Sciences was important and should be offered in high school. In addition, only 9.3% (10) have considered Family and Consumer Sciences education as a career, 63.7% have never thought of it as a possible career, and 17.8% indicated there was not enough available jobs. The study determined that most of the Family and Consumer Sciences teacher participants declared there was not a decline in enrollment in classes over the past ten years. Two of the seven teachers will be retiring within the next five years.
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Development of standardized sizing systems for the South African children’s wear marketVan Huyssteen, S. 04 1900 (has links)
Thesis (DSc (Consumer Science)--University of Stellenbosch, 2006. / 326 leaves on CD format, preliminary i-xix pages and numbered pages 1-210. Includes bibliography, list of tables, figures and appendixes. / ENGLISH ABSTRACT: This research focused on the need of the children’s wear industry in South Africa for sizing systems based on accurate and current body measurement tables developed from the actual measurements of children. The broad objective of this study was to develop standardised measuring methodologies and techniques which would be relevant to the subsequent development of reliable, accurate and comprehensive body measurement tables. These tables could then be implemented as a basis for the development of new sizing systems, as well as new, improved and authentic fit dummy ranges. The literature study served as a point of departure for the planning and execution of the empirical study, focusing on sizing and size designation systems. The study population comprised children representative of three categories, namely age (2 to 14 years), gender (boys and girls) and sector (Black and Non-Black) categories. A convenience sample was selected, representing children from two geographical areas (Western Cape and Gauteng). The empirical study has a three phase structure. The first pilot study aimed at developing standardised measuring equipment, as well as the methodologies and properly recorded guidelines for their implementation. The specific standards according to which subjects were measured and the strict quality control measures implemented to ensure the validity, reliability and accuracy of recorded data, were confirmed during the second pilot study. Based on this, the final study was executed following the guidelines as recorded in the Field Worker Manual. The statistical analysis was done after data capturing during which the data sets were first cleaned up. Secondly, the key measurements for use as a basis for the development of the sizing systems were identified. Based on these, body measurement tables were compiled and age of gender split and growth patterns were analysed for fit dummy prototype development. The new size designation system developed for children’s clothing was successfully implemented as a multi-indicator system, linking height ranges with both age ranges and numerical size indicators. The development of the subsequent new and improved fit dummy prototypes was based on measurements within minimum and maximum values of the body measurements, in order to facilitate the construction of these three-dimensional bodies. It was also possible to develop complete body measurement tables with accurate, and notably irregular, increments between sizes as well as to determine specific growth patterns and separate growth spurts for both boys and girls. This study made new and original as well as more detailed and correct information available concerning the size and shape of the typical South African children’s wear consumer. Using the information contained in the new height based sizing system, retailers have been able to develop a proper set of grade rules for application in product development. The identification and demarcation of important body landmarks facilitated pattern drafting, garment development and fit assessments, resulting in an improved product offering for the typical South African children’s wear consumer. Recommendations regarding further research were formulated, such as comparing the study population categories, namely gender, age and sector. Implications for retailers, inter alia that each retail company could choose how to implement the new height based sizing system and the specific size designation system most suitably for their own consumers and internal systems. The standards set and methodologies implemented in this survey were an improvement on the sizing and fit of children’s wear in the context of South African manufacturers, retailers and consumers. / AFRIKAANSE OPSOMMING: Hierdie navorsing fokus op die behoefte van die Suid-Afrikaanse kinderklerekleinhandelbedryf aan ‘n sisteem van kleregroottes, gebaseer op akkurate en huidige liggaamsmate-tabelle wat ontwikkel is van die werklike mates van kinders. Die oorkoepelende doelstelling van hierdie studie was om gestandaardiseerde meetmetodologieë en -tegnieke te ontwikkel wat relevant is vir die daarstelling van betroubare, akkurate en omvattende liggaamsmate-tabelle, wat dan gebruik kan word as basis vir die nuwe kleregroottesisteem, sowel as om nuwe, verbeterde en oorspronklike figuurmodelreekse te ontwikkel. Die literatuurstudie het gedien as vertrekpunt vir die beplanning en uitvoering van die empiriese studie met die fokus op kleregroottesisteme en kleregrootteaanwysingsisteme. Die kinders in die studiepopulasie het drie kategorieë verteenwoordig: ouderdom (2 tot 14 jaar), geslag (seuns en meisies) en sektor (Swart en Nie-Swart). ‘n Gerieflikheidsteekproef is uit twee geografiese areas (Wes-Kaap en Gauteng) gekies. Die empiriese studie het ‘n drie-fase-struktuur. Die eerste loodsstudie het ten doel gehad om gestandaardiseerde meettoerusting, meetmetodologieë en behoorlik aangetekende implementeringsriglyne daar te stel. Die spesifieke standaarde waarvolgens die proefpersone gemeet is en die implementering van streng kwaliteitbeheermaatreëls wat geldige, betroubare en akkuraat vasgelegde data verseker, is tydens die tweede loodsstudie bevestig. Die finale studie is gebaseer op en uitgevoer volgens die riglyne soos uiteengesit in die Field Worker Manual. Die statistiese analise is gedoen nadat die data vasgelê en skoongemaak is. Vervolgens is sleutelmates geïdentifiseer wat as basis vir die ontwikkeling van kleregroottesisteme kan dien. Volledige liggaamsmate-tabelle is daarna ontwikkel. Die identifisering van die geslagverdelingsouderdom, sowel as die analisering van groeipatrone vir die ontwikkeling van figuurmodelle, is hierop gebaseer. Die nuwe klere-aanwysingsisteme wat ontwikkel is vir kinderklere is suksesvol geïmplementeer as ‘n veelvoudige aanwysingsisteem wat liggaamslengtereekse met ouderdomsreekse en numeriese grootte-aanwysers koppel. Die nuwe en verbeterde figuurmodel-prototipes wat vervolgens ontwikkel is, is gebaseer op minimum en maksimum waardes van die liggaamsmates ten einde die konstruksie van die driedimensionele figure te vergemaklik. Daarbenewens was dit moontlik om volledige liggaamsmate-tabelle met akkurate en opmerklik ongelyke inkremente tussen groottes daar te stel, sowel as om die spesifieke groeipatrone en afsonderlike groeitoenames vir beide seuns en meises te bepaal. Die studie het nuwe en oorspronklike, sowel as meer gedetailleerde en korrekte inligting ten opsigte van die grootte en vorm van die tipiese Suid-Afrikaanse kinderklereverbruiker beskikbaar gestel. Met hierdie nuwe kennis van die liggaamslengte-gebaseerde kleregroottesisteem, is dit nou vir kleinhandelaars moontlik om ‘n volledige stel graderingsreëls daar te stel en in produkontwikkeling toe te pas. Die identifikasie en afbakening van belangrike liggaamsbakens vergemaklik patroon- en klereontwikkeling sowel as die evaluering van die mate waarin dit pas; dit waarborg ‘n verbeterde produk vir die tipiese Suid-Afrikaanse kinderklereverbruiker. Aanbevelings vir verdere navorsing is gemaak, soos ‘n vergelyking van die studiepopulasiekategorieë, naamlik geslag, ouderdom en sektor. Die implikasies vir kleinhandelaars is onder meer dat elke kleinhandelaar kan kies hoe om hierdie nuwe liggaamslengte-gebaseerde kleregroottesisteem te implementer en watter die mees geskikte kleregrootte-aanwysingsisteem vir hul verbruikers en interne sisteme sal wees. Die standaarde wat vir hierdie studie gestel is, sowel as die metodologieë wat geïmplementeer is, is ‘n aansienlike verbetering op die groottes en pas van kinderklere binne die konteks van die Suid-Afrikaanse vervaardigers, kleinhandelaars en verbruikers.
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A participatory action research approach to programme evaluation in a rural societyBester, Alte 03 1900 (has links)
Thesis (MA)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Recently, Participatory action research (PAR) has become a common approach to
social programmes in South Africa. This tendency has created a need to evaluate
this kind of programmes to determine if it really achieves what it sets out to do. The
purpose of this study was to evaluate an entrepreneurial skills training programme in
a rural community where a participatory action research approach was followed.
A literature review was undertaken to present an in-depth look into the body of
literature that surrounds the study. Programme evaluation was discussed as a
research design, including types and stages of evaluation. The concept of
empowerment was investigated. The review also included a study of literature on
PAR, especially the definitions, context and process of PAR. The role of
entrepreneurship in rural development was also investigated as well as the
evaluation of entrepreneurial skills training programmes.
An entrepreneurial skills training programme was implemented in the rural town of
Darling on the West Coast of South Africa. The PAR approach was followed in the
implementation of the study that was conducted over a period of 15 months.
Participants joined the programme that included different projects, voluntarily. The
participants were divided into three groups according to their period of participation in
the programme. The researcher facilitated actions as well as reflection meetings with
the group of participants before and after the entrepreneurial skills training course.
The researcher made field notes during the implementation of the programme. The
participants' empowerment status was measured with a standardized questionnaire
using a pre-test-post-test design. The participants' application of the entrepreneurial
skills that were taught in the course was measured during semi-structured interviews
at the end of the research perico. four case studies document the extremes of the
respective outcomes of the programme, namely empowerment and entrepreneurship.
Statistical analysis showed statistically significant improvements in the micro, macro
and total empowerment scores of the total group. Looking at the three groups
separately, group one showed statistically significant improvements on the micro and interface levels and group two on the micro level. Even though group three showed
small improvements on all three levels, none of them were statistically significant.
Data from the field notes wer:e analyzed according to the PAR concepts of
participation, action and reflection. Participation mostly had a collaborative nature;
action was aimed at economical change and reflection aimed at practical problem
solving. The interviews revealed that 20 of the 24 participants had micro baking
businesses at the end of the research period and they succeeded in the short-term
goal of applying the skills that were taught in the course. The case studies showed no
correlation between the participants' application of entrepreneurial skills and the
changes in their empowerment status.
The findings of the study suggest that the longer participants participate in a PAR
programme, the bigger the improvement in their empowerment status will be.
Monitoring of the implementation revealed that the study fell short of the "ideal type"
of PAR, since participation was not yet collegiate. Actions were only effective in
economic change and not in social transformation. Reflection resulted in limited
critical self-awareness among the participants. The PAR approach has proven to be
successful in the attainment of the short-term goals of an entrepreneurial skills
training programme. The long-term sustainability of the entrepreneurs' businesses
will have to be followed-up by further research. / AFRIKAANSE OPSOMMING: Die afgelope tyd is deelnemende aksie navorsing (DAN)'n algemene benadering tot
sosiale intervensie programme in Suid-Afrika. Hierdie tendens het 'n behoefte laat
ontstaan om hierdie tipe programme te evalueer om te bepaal of dit werklik die
program doelwitte bereik. Die doel van hierdie studie was om 'n
entrepreneursvaardighede opleidingsprogram in 'n landelike gemeenskap waar die
DAN-benadering gevolg is, te evalueer.
'n Literatuuroorsig is onderneem om die konseptueie raamwerk wat vir die studie
saamgestel is, te kan beredeneer. Programevaluering, insluitende tipes and stadia
van evaluering, is bespreek as 'n navorsingsontwerp. Die konsep van bemagtiging is
ook bestudeer. Die oorsig het 'n ook studie van literatuur oor DAN ingesluit, veral
definisies, die konteks en die proses van DAN. Die rol van entrepreneurskap in
landelike ontwikkeling is 00~ ondersoek sowel as die evaluering van
opleidingsprogramme gemik op die ontwikkeling van entrepreneursvaardighede.
'n Entrepreneursvaardighede opleidingsprogram is in 'n landelike dorpie, Darling, aan
die Weskus van Suid-Afrika geïmplementeer. Oor 'n periode van 15 maande is die
DAN-benadering in die implementering van die program gevolg. Deelnemers het
vrywillig by die program wat uit verskillende projekte bestaan het, aangesluit. Die
deelnemers is na aanleiding van hul tydperk van deelname in die program in drie
groepe verdeel. Die navorser het aksies sowel as refleksie byeenkomste met die
groep deelnemers voor en na die entrepreneursvaardighede opleidingskursus
gefasiliteer. Die navorser het veldnotas tydens die implementering van die program
gemaak. Die deelnemers se bemagtigingstatus is gemeet met 'n gestandaardiseerde
vraelys terwyl 'n voor-en-na-toets ontwerp gevolg is. Die deelnemers se toepassing
van die entrepreneursvaardighede wat in die kursus geleer is, is tydens semigestruktureerde
onderhoude aan die einde van die navorsingsperiode gemeet. Vier
gevallestudies dokumenteer die uiterstes van die onderskeidelike uitkomste van die
program, naamlik bemagtiging en entrepreneurskap. Statistiese analise het statisties betekenisvolle verbeteringe in die mikro, makro en
totale bemagtigingsvlakke van die totale groep getoon. Afsonderlik gesien, het groep
een statisties betekenisvolle verbeteringe op die mikro en tussenvlak getoon en
groep twee net op die mikrovlak. Alhoewel groep drie klein verbeteringe op al drie
vlakke getoon het, was geen van die verbeteringe statisties betekenisvol nie. Data
van die veldnotas is volgens DAN konsepte, naamlik deelname, aksie en refleksie
geanaliseer. Die deelnemers en die fasiliteerder se deelname het meestal In
samewerkende aard gehad, aksie was gemik op ekonomiese verandering en
refleksie was gemik op praktiese probleemoplossinq. Die onderhoude het aangetoon
dat 20 van die 24 deelnemers aan die einde van die navorsingsperiode In mikro
bakbesigheid gehad het en dat hulle daarin geslaag het om die korttermyn doelwit,
naamlik die toepassing van die vaardighede wat in die kursus geleer is, te bereik. Die
gevallestudies het geen korrelasie getoon tussen die deelnemers se toepassing van
entrepreneursvaardighede en die veranderinge in hulle bemagtigingstatus nie.
Die studie se bevindinge dui daarop dat hoe langer deelnemers aan In DAN-program
deelneem, hoe groter sal die verbetering in hulle bemagtigingstatus wees. Die
monitering van die implementering van die program het laat biyk dat die studie tekort
skiet in vergelyking met die "ideaaltipe" van DAN, want die deelname was nog nie
korporatief nie. Aksies was net suksesvol in ekonomiese verandering en nie in
sosiale transformasie nie. Refleksie het tot beperkte kritiese "selfbewustheid" by die
deelnemers gelei. Dit blyk dat die DAN-benadering suksesvol was om die korttermyn
doelwitte van In entrepreneursvaardighede opleidingsprogram te bereik. Die
langtermyn volhoubaarheid van die entrepreneurs se bakbesighede sal met verdere
navorsing opgevolg moet word.
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