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Packaging of table grapes for exports from SA : a comparative studyNieuwoudt, Tania 04 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Table grapes are the second-largest contributor to the perishable product export in
South Africa. The table grape industry also experienced considerable growth in the
past ten years. The industry contributes toward employment in South Africa. The
South African table grape industry experiences quality-related problems with
exporting table grapes to the European market. Examples of quality related problems
can range from chemical damage, chilling injury/freezing damage, heavy bruising
and decay. A great amount of table grapes is basically wasted. The postharvest loss
of table grapes during transportation can range from 1%-25% per day depending on
the degree of temperature fluctuation. Therefore, it is important to minimize waste
and increase the export volumes in order to utilise the potential profit possibilities.
Based on data analysis for this case, results indicated that packaging is preventing
cool air from flowing through the pallet during transportation and preventing the table
grapes to cool evenly. The fluctuation in temperature contributes to the qualityrelated
problems of these table grapes. The primary research goal is to identify
packaging-related problems and propose possible solutions to improve the
packaging-related conditions in which table grapes arrive at the destination. This
study therefore investigated and evaluated the performance of the current packaging
system of table grapes within a South African context for exporting to Europe for a
specific case. Further analyses of the data received from Dole South Africa, a fruit
marketing and distribution company, revealed that the following two types of
packaging showed serious quality-related problems:
1) A04I: The 4.5kg box with the grapes in plastic bags.
2) A05E: The 5kg box with 500g punnets (10 x 500g punnets).
A questionnaire combining with the Packaging Portfolio Evaluation Model and the
Packaging Scorecard was developed and used to evaluate the two identified
packaging systems in the following stages:
Stage 1: Development of a new questionnaire by combining the Packaging Portfolio
Evaluation Model and the Packaging Scorecard.
Stage 2: Survey with the questionnaire developed in Stage 1. The identified types of
packaging were evaluated with a new questionnaire with specific criteria. Members of
the table grape supply chain from the farmer in South Africa to consumer in Sweden
were used during the evaluation process.
Descriptive statistics were calculated for each criteria or question in order to describe
the performance and importance of the different packaging criteria. Data were also
analysed with the use of box plots. The box plots and data visualisation methods
were used to make conclusions and recommendations regarding the different
categories of each type of packaging. It was clear that the major problem areas of
both packaging systems involved were related to the environmental aspect of the
packaging. The marketing and the logistics of the plastic bag also underperformed.
However, individual criteria regarding the other business areas can also be improved.
Possible solutions to these problem areas are also suggested in this thesis. The
possible solutions include the Tali Grape Basket, Perforated Plastic Liners, New Generation Pack (NGP), Vinguard TM
, Easypunnet and the Sulphur Dioxide Liner
Bag. / AFRIKAANSE OPSOMMING: Tafeldruiwe is die tweede grootste bydraende faktor tot bederfbare produkuitvoere in
Suid-Afrika. Die tafeldruifindustrie het ook aansienlike groei die afgelope tien jaar
beleef. Die industrie dra tot werkskepping in Suid-Afrika by. Die Suid-Afrikaanse
tafeldruifindustrie ervaar kwaliteitsverwante probleme met die uitvoer van tafeldruiwe
na die Europese mark. Voorbeelde van hierdie kwaliteitsverwante probleme kan
wissel van chemiese skade, koueskade / vries skade, swaar kneusing en bederf. ‘n
Groot hoeveelheid tafeldruiwe word vermors. Die oes verlies van tafeldruiwe tydens
vervoer kan wissel van 1% -25% per dag, afhangende van die mate van temperatuur
verandering. Daarom is dit belangrik om vermorsing te beperk en
uitvoerhoeveelhede te verhoog om sodoende potensiële winsmoontlikhede te benut.
Volgens data-analise blyk dit dat huidige verpakking tans verhoed dat koel lug tydens
die vervoer van die produk deur die palet vloei, en dit veroorsaak dat die tafeldruiwe
nie eweredig afkoel nie. Die wisseling in temperatuur dra grootliks tot die
kwaliteitsverwante probleme van die tafeldruiwe by. Die primêre navorsingsdoelwit is
om die verpakkingsverwante probleme te identifiseer en moontlike oplossings voor te
stel om sodoende die toestand te verbeter waarin tafeldruiwe by die eindbestemming
aankom. Daarom ondersoek en evalueer hierdie studie die prestasie van die huidige
verpakkingsisteem van tafeldruiwe binne ʼn Suid-Afrikaanse konteks vir uitvoere na
Europa; met betrekking tot ʼn spesifieke situasie.
Verdere analise van data soos ontvang vanaf Dole Suid-Afrika, ‘n vrugtebemarkingsen
verspreidingsmaatskappy, het getoon dat ernstige kwaliteitsverwante probleme
veral by die volgende twee tipes verpakkingsisteme voorkom:
1) A04I: Die 4.5kg karton met druiwe in plastieksakkies.
2) A05E: Die 5kg karton met 500g bakkies (10 x 500g bakkies).
ʼn Vraelys, gebaseer op die kombinasie van die Verpakkingportefeulje
Evalueringsmodel model en die Verpakkingstelkaart, is ontwikkel en gebruik om die
bogenoemde verpakkingsisteme te evalueer en wel in die volgende fases:
Fase 1: Ontwikkeling van ʼn gekombineerde Verpakkingsportefeulje
Evalueringsmodel en die Verpakkingstelkaart tot ʼn nuwe vraelys. Fase 2: Opname met die vraelys soos ontwikkel in Fase 1. Die twee geïdentifiseerde
tipes verpakking is geëvalueer met die nuwe vraelys met spesifieke kriteria. Die lede
van die tafeldruiwe voorsieningsketting van die boer in Suid-Afrika tot die verbruiker
in Swede is gebruik tydens die evaluasieproses.
Beskrywende statistiek vir elke kriteria of vraag was bereken sodat die prestasie en
belangrikheid van die verskillende verpakkingskriteria beskryf kan word. Data was
ook beskryf met behulp van ‘n houer-en-puntstipping. Data visualiseringmetodes en
die houer-en-puntstippings was gebruik om gevolgtrekkings en aanbevelings
rakende die verskillende kategorieë van die tipes verpakking te maak. Dit was
duidelik dat die omgewingsaspek van beide tipes verpakking ‘n groot probleem was.
Die bemarking en logistiek van die plastieksakkie het ook onderpresteer. Individuele
kriteria van ander besigheidsareas kan egter ook verbeter word. Moontlike
oplossings vir hierdie probleem-areas word ook in hierdie tesis aangedui. Die
moontlike oplossings sluit die “Tali Grape Basket”, “Perforated Plastic Liners”, “New
Generation Pack (NGP)”, “Vinguard TM
”, “Easypunnet” en die “Sulphur Dioxide Liner
Bag” in
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Resistance to airflow and moisture loss of table grapes inside multi-scale packagingNgcobo, Mduduzi Elijah Khulekani 03 1900 (has links)
Thesis (PhD(Agric))--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Postharvest quality of fresh table grapes is usually preserved through cooling using cold air. However, cooling efficiencies are affected by the multi-scale packaging that is commercially used for handling grapes after harvest. There is usually spatial temperature variability of grapes that often results in undesirable quality variations during postharvest handling and marketing. This heterogeneity of grape berry temperature inside multi-packages is largely due to uneven cold airflow patterns that are caused by airflow resistance through multi-package components. The aims of this study were therefore to conduct an in-depth experimental investigation of the contribution of grape multi-packaging components to total airflow resistance, cooling rates and patterns of grapes inside the different commercially used multi-packages, and to assess the effects of these multi-packages on table grape postharvest quality attributes. A comprehensive study of moisture loss from grapes during postharvest storage and handling, as well as a preliminary investigation of the applicability of computational fluid dynamics (CFD) modeling in predicting the transport phenomena of heat and mass transfer of grapes during cooling and cold storage in multi-packages were included in this study.
Total pressure drop through different table grapes packages were measured and the percentage contribution of each package component and the fruit bulk were determined. The liner films contributed significantly to total pressure drop for all the package combinations studied, ranging from 40.33±1.15% for micro-perforated liner film to 83.34±2.13 % for non-perforated liner film. The total pressure drop through the grape bulk (1.40±0.01 % to 9.41±1.23 %) was the least compared to the different packaging combinations with different levels of liner perforation. The cooling rates of grapes in the 4.5 kg multi-packaging were significantly (P<0.05) slower than that of grapes in 5 kg punnet multi-packaging, where the 4.5 kg box resulted in a seven-eighths cooling time of 30.30-46.14% and 12.69-25.00% more than that of open-top and clamshell punnet multi-packages, respectively. After 35 days in cold storage at -0.5°C, grape bunches in the 5 kg punnet box combination (open-top and clamshell) had weight loss of 2.01 – 3.12%, while the bunches in the 4.5 kg box combination had only 1.08% weight loss. During the investigation of the effect of different carton liners on the cooling rate and quality attributes of ‘Regal seedless’ table grapes in cold storage, the non-perforated liner films maintained relative humidity (RH) close to 100 %. This high humidity inside non-perforated liner films resulted in delayed loss of stem quality but significantly (P ≤ 0.05) increased the incidence of SO2 injury and berry drop during storage compared to perforated liners. The perforated liners improved fruit cooling rates but significantly (P ≤ 0.05) reduced RH. The low RH in perforated liners also resulted in an increase in stem dehydration and browning compared to non-perforated liners.
The moisture loss rate from grapes packed in non-perforated liner films was significantly (P<0.05) lower compared to the moisture loss rate from grapes packed in perforated liner films (120 x 2 mm and 36 x 4 mm). The effective moisture diffusivity values for stem parts packed in non-perforated liner films were lower than the values obtained for stem parts stored without packaging liners, and varied from 5.06x10-14 to 1.05x10-13 m2s-1. The dehydration rate of stem parts was inversely proportional to the size (diameter) of the stem parts. Dehydration rate of stems exposed (without liners) to circulating cold air was significantly (P<0.05) higher than the dehydration rates of stems packed in non-perforated liner film. Empirical models were successfully applied to describe the dehydration kinetics of the different parts of the stem. The potential of cold storage humidification in reducing grape stem dehydration was investigated. Humidification delayed and reduced the rate of stem dehydration and browning; however, it increased SO2 injury incidence on table grape bunches and caused wetting of the packages.
The flow phenomenon during cooling and handling of packed table grapes was also studied using a computational fluid dynamic (CFD) model and validated using experimental results. There was good agreement between measured and predicted results. The result demonstrated clearly the applicability of CFD models to determine optimum table grape packaging and cooling procedures. / AFRIKAANSE OPSOMMING: Naoes kwaliteit van vars tafeldruiwe word gewoonlik behou deur middel van verkoeling van die produk met koue lug. Ongelukkig word die effektiwiteit van dié verkoeling beïnvloed deur die multivlakverpakking wat kommersieel gebruik word vir die naoes hantering van druiwe. Daar is gewoonlik ruimtelike variasie in die temperatuur van die druiwe wat ongewenste variasie in die kwaliteit van die druiwe veroorsaak tydens naoes hantering en bemarking. Die heterogene druiwetemperature binne die multivlakverpakkings word grootliks veroorsaak deur onegalige lugvloeipatrone van die koue lug as gevolg van die weerstand wat die verskillende komponente van die multivlakverpakkings teen lugvloei bied. Die doel van hierdie studie was dus om ‘n indiepte eksperimentele ondersoek te doen om die bydrae van multivlakverpakking op totale lugvloeiweerstand, verkoelingstempo’s en –patrone van druiwe binne kommersieël gebruikte multivlakverpakkings te ondersoek, asook die effek van die multivalkverpakking op die naoes kwaliteit van druiwe te bepaal. ‘n Omvattende studie van vogverlies van druiwe tydens naoes opberging en hantering, asook ‘n voorlopige ondersoek na die bruikbaarheid van ‘n berekende vloei dinamika (BVD) model om die bewegingsfenomeen van hitte en massa oordrag van druiwe tydens verkoeling en koelopberging in multivlakverpakkings te voorspel, was ook by die studie ingesluit. Die totale drukverskil deur verskillende tafeldruif verpakkingssisteme is gemeet en die persentasie wat deur elke verpakkingskomponent en die vruglading bygedra is, is bereken. Van al die verpakkingskombinasies wat gemeet is, het die voeringfilms betekenisvol tot die totale drukverskil bygedra, en het gewissel van 40.33±1.15% vir die mikro geperforeerde voeringfilm tot 83.34±2.13 % vir die nie-geperforeerde voeringfilm. Die totale drukverskil oor die druiflading (1.40±0.01 % to 9.41±1.23 %) was die minste in vergelyking met die verskillende verpakkingskombinasies met die verskillende vlakke van voeringperforasies.
Die verkoelingstempos van die druiwe in die 4.5 kg multiverpakking was betekenisvol (P<0.05) stadiger as vir die druiwe in die 5 kg handmandjie (‘punnet’) multiverpakking. Die 4.5 kg karton het ‘n seweagstes verkoelingstyd van 30.30-46.14% en 12.69-25.00% langer, respektiewelik, as oop-vertoon en toeslaan-‘punnet’ multiverpakkings gehad. Na 35 dae van koelopberging by -0.5°C het druiwetrosse in die 5 kg ‘punnet’-kartonkombinasies (oop-vertoon en toeslaan-’punnet’) ‘n massaverlies van 2.01 – 3.12% gehad, terwyl die trosse in die 4.5 kg kartonkombinasie slegs ‘n 1.08% massaverlies gehad het.
In die ondersoek na die effek van verskillende kartonvoerings op die verkoelingstempo en kwaliteitseienskappe van ‘Regal seedless’ tafeldruiwe tydens koelopbering, het die nie-geperforeerde kartonvoerings ‘n relatiewe humiditeit (RH) van byna 100 % gehandhaaf. Hierdie hoë humiditeit in die nie-geperforeerde voeringfilms het ‘n verlies in stingelkwaliteit vertraag, maar het die voorkoms van SO2-skade en loskorrels betekenisvol (P < 0.05) verhoog in vergelyking met geperforeerde voerings. Die geperforeerde voerings het vrugverkoelingstempos verbeter, maar het die RH betekenisvol (P ≤ 0.05) verlaag. Die lae RH in die geperforeerde voerings het gelei tot ‘n verhoging in stingeluitdroging en –verbruining in vergelyking met die nie-geperforeerde voerings. Die vogverliestempo uit druiwe verpak in nie-geperforeerde voeringfilms was betekenisvol (P<0.05) stadiger in vergelyking met druiwe verpak in geperforeerde voeringfilms (120 x 2 mm and 36 x 4 mm). Die effektiewe vogdiffusiewaardes vir stingelgedeeltes verpak in nie-geperforeerde voeringfilms was stadiger as vir stingelgedeeltes wat verpak is sonder verpakkingsvoerings, en het gevarieer van 5.06x10-14 – 1.05x10-13 m2s-1. Die uitdrogingstempo van stingelgedeeltes was omgekeerd eweredig aan die grootte (deursnit) van die stingelgedeeltes. Die uitdrogingstempo van stingels wat blootgestel was (sonder voerings) aan sirkulerende koue lug was betekenisvol (P<0.05) hoër as die uitdrogingstempos van stingels wat verpak was in nie-geperforeerde voeringfilms. Empiriese modelle is gebruik om die uitdrogingskinetika van die verskillende stingelgedeeltes te beskryf.
Die potensiaal van koelkamer humidifisering in die vermindering van die uitdroging van druifstingels is ondersoek. Humidifisering het stingeluitdroging vertraag en het die tempo van stingeluitdroging en -verbruining verminder, maar dit het die voorkoms van SO2-skade op die tafeldruiftrosse verhoog en het die verpakkings laat nat word.
Die bewegingsfenomeen tydens verkoeling en hantering van verpakte tafeldruiwe is ook ondersoek deur gebruik te maak van ‘n BVD model en is bevestig met eksperimentele resultate. Daar was goeie ooreenstemming tussen gemete en voorspelde resultate. Die resultaat demonstreer duidelik die toepaslikheid van BVD-modelle om die optimum tafeldruifverpakkings- en verkoelingsprosedures te bepaal. / PPECB and Postharvest Innovation Programme (PHI-2) for their financial support
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Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.)Du Plessis, S. F. (Stephanus Francois) 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: The table grape industry uses rapid cooling and packaging to protect grapes from desiccation
and decay. Numerous packaging methods and combinations are used in the industry with
each having their own advantages and disadvantages.
Inferior postharvest grape quality can usually be ascribed to either deficient or excessive
moisture in the carton. Berry split, decay and S02 damage are all disorders that are either
caused or aggravated by wet berries in conjunction with elevated temperature. On the other
hand, grapes that are exposed to desiccating conditions will develop brown stems and cause
ineffective control by S02 gas generators. Moisture management is governed by perforated
or non-perforated liners and/or by placing moisture absorbing materials inside the liners. To
find the optimum liner perforation or moisture sheet combination, 'Thompson Seedless' and
'Red Globe' (Vitis vinifera Linnaeus) table grape quality was evaluated in various trials.
The investigation of non-perforated liners compared to liners with different degrees of
perforation concluded the following: Perforated liners benefit grape quality by decreasing
S02 damage and berry split due to less moisture in the carton. These benefits, however, also
lead to loss in quality due to increased stem desiccation and a lower S02 concentration in the
packaging. The lower moisture content in the carton compensates for the lower S02
concentration, creating an environment less favourable for decay development. S02 damage
and berry split decreased with an increase in degree of liner perforation, irrespective of the
cultivars sensitivity to the disorder. Optimum level of perforation depends on the specific
sensitivity of a cultivar to certain quality disorders and the characteristics of the quality
disorders associated with a cultivar. Additionally, packing conditions such as product
temperature and humidity should be considered. The specific costs associated with the
advantages and disadvantages influenced by the degree of liner perforation will be the
deciding factor in liner selection.
The investigation of a clay-containing, moisture absorbing sheet emphasized the benefits and
risks of absorbing large amounts of water within the packaging. Irrespective of using a
perforated or non-perforated liner the influence of the desiccant sheet was evident throughout
the trials. It benefited grape quality by lowering the incidence of berry split and S02 damage. However, decay control was impaired by the desiccant sheet, and stem desiccation was
aggravated.
The comparison of non-perforated liners with liners of various degrees of perforation showed
the benefit of faster cooling rates of perforated liners. The various perforated liners showed
little variation in airflow and cooling times.
Morphological studies of various cultivars could not ascribe differences in stem condition to
anatomical dissimilarities between various cultivars. It was found that 'Red Globe' had a
much larger berry volume to stem weight ratio contributing to a high rate of water loss and
stem dehydration. Stem visibility is high in 'Red Globe' due to the straggly, loose nature of
the bunches. This heightens the perception of dry, brown stems and overemphasizes the
actual severity of the disorder. / AFRIKAANSE OPSOMMING: Die tafeldruifbedryf gebruik versnelde verkoeling en verpakking om druiwe te beskerm teen
uitdroging en bederf. Verskeie verpakkingsmetodes word gebruik in die industrie waarvan
elkeen sy eie voor- en nadele het.
Ondergeskikte na-oes kwaliteit kan gewoonlik toegeskryf word aan óf te min óf te veel vog
in die karton. Korrelbars, S02 skade en bederf is almal kwaliteitsdefekte wat óf veroorsaak
word, óf vererger word deur nat korrels, saam met 'n verhoging in temperatuur. In
teenstelling hiermee sal druiwe wat blootgestel word aan droë toestande, bruin stingels
ontwikkel en S02 beheer salook ondoeltreffend wees. Vog in verpakking word beheer deur
geperforeerde of nie-geperforeerde binnesakke en/of deur vogabsorberende materiaal binne
die binnesak te plaas. Om die optimum binnesak perforasie of vogabsorberende vel
kombinasie te vind is 'Thompson Seedless' en 'Red Globe' (Vitis vinifera Linnaeus)
tafeldruif kwaliteit ge-evalueer in verskeie proewe.
Die bestudering van nie-geperforeerde binnesakke teenoor binnesakke met verskillende grade
van perforasies het die volgende resultate gelewer: Geperforeerde binnesakke bevoordeel
druif kwaliteit deur die vermindering van S02 skade en korrelbars weens minder vog in die
karton. Hierdie voordele sal egter lei tot verlies in kwaliteit weens die vinniger uitdroging
van stingels en die verlaging van S02 konsentrasie in die verpakking. Die laer vog inhoud in
die karton vergoed vir die vermindering van S02 konsentrasie, omdat minder gunstige
toestande vir die ontwikkeling van bederf geskep word. S02 skade en korrelbars het
verminder met 'n vermeerdering van perforasies, ongeag die kultivar se sensitiwiteit vir die
defekte. Optimum vlakke van perforasie is afhanklik van die spesifieke sensititiwiteit van 'n
kultivar tot sekere kwaliteitsdefekte, en eienskappe van die kwaliteitsdefekte wat geassosieer
word met die kultivar. Boonop moet verpakkingsomstandighede soos produktemperatuur en
humiditeit ook in gedagte gehou word. Die spesifieke koste verbonde aan die voor- en nadele
wat beïnvloed word deur die graad van perforasie sal die bepalende faktor wees wanneer 'n
binnesak gekies word.
Die bestudering van 'n klei-bevattende, vogabsorberende vel het bewys dat dit voordele en
risiko's inhou om groot hoeveelhede vog te absorbeer. Ongeag die gebruik van 'n geperforeerde of nie-geperforeerde binnesak, was die invloed van die desikkante vel duidelik
in al die proewe. Dit was voordelig vir druif kwaliteit deurdat dit korrelbars en S02 skade
verminder het. Bederfbeheer is egter verswak deur die desikkante vel, en stingel uitdroging
IS vererger.
Die vergelyking van nie-geperforeerde binnesakke met verskillende grade van geperforeerde
binnesakke het die voordeel bewys van vinniger verkoelinstempo's van die geperforeerde
binnesak. Verskille in die graad van perforasie het 'n klein invloed gehad op die lugvloei en
verkoelingstempo 's.
Bestudering van verskeie kultivars kon geen morfologiese verskille uitwys wat variasie in
stingelkwaliteit tussen kultivars kan verklaar nie. Dit is bevind dat 'Red Globe' 'n baie groter
korrelvolume tot stingelgewig verhouding het. Stingels is meer sigbaar by 'Red Globe'
weens die yl, los aard van die trosse. Dit verhoog die persepsie van droë, bruin stingels en dit
oorbeklemtoon die voorkoms van die defek.
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Check weighing in table grape punnet packing: Opportunities in the development of operational effectivenessSmit, Rudi 12 1900 (has links)
Thesis (MScEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: South Africa is ranked as one of the largest table grape exporting countries in the world.
The biggest markets for table grape exports have always been the EU and the UK, with
emerging markets in Eastern Europe and Asia. The growing demand for pre-packaged
fruit and vegetables in these markets are driven by factors like consumer comfort, hygiene
and quality. These consumer needs have given rise to stringent quality control standards,
putting more pressure on the producers to produce higher quality products.
This thesis investigates the use of check weighing as a tool to enhance the operational
effectiveness of table grape punnet packing. It looks at the current state of table grape
punnet packing in South Africa, then determines the operational effectiveness of current
packing practices and finally evaluates the merits of using automated check weighing as
an operational management tool to improve current systems.
Producers primarily make use of unskilled labour for the pre-packaging of table grapes,
making it difficult to consistently produce good quality products. Some packing systems
guide the operators towards filling punnets to the specified mass; some packing systems
also feature internal check weighing in some form. Although these features improve mass
accuracy and hence product quality, the packing processes are still prone to human and
machine errors. Producers employ internal quality controllers who try to identify and rectify
any human or machine errors as soon as possible.
The PPECB, a local statutory body, enforces the minimum quality standards for South
African exports by means of inspectors checking random product samples during
production. If products of sub-standard quality are found (including under mass), the whole
batch needs to be checked and repackaged where necessary, at great cost to the
producer. Pre-packaged products may be produced according to the minimum mass system or the
average mass system. The average mass system reduces the amount of raw product
giveaway and increases revenue, but it requires that all products are check weighed and
the masses recorded with a specified level of accuracy.
The addition of automated final product check weighing saw a significant reduction in the
occurrence of under as well as over mass punnets. It also managed to improve the
productivity of some packing systems. Subsequent experiments with the check weigher
using different setup parameters yielded much better measurement accuracy and would
reduce under and over mass punnets even more.
Considering the potential costs of having to repack batches due to the discovery of under
mass products, it would be viable to implement automated final product check weighing
even for small producers, with a payback period of less than 5 packing seasons depending
on the producer’s specific pack house layout.
The implementation of check weighing could not only reduce the risk of sub-quality
products being produced, but also open up entirely new market opportunities in a very
competitive market for products produced to the average mass system. / AFRIKAANSE OPSOMMING: Suid-Afrika is een van die grootste tafeldruiwe-uitvoerders ter wêreld. Die hoofmarkte vir
tafeldruiwe-uitvoere was nog altyd die Europese Unie en Verenigde Koninkryk, met
opkomende markte in Oos-Europa en Asië. Die groeiende behoefte vir voorafverpakte
vrugte en groente in hierdie markte word gedryf deur verbruikersfaktore soos
gemaksugtigheid, higiëne en kwaliteit. Hierdie behoeftes het tot gevolg gehad dat
strenger reëls en regulasies vir kwaliteitsbeheer ontstaan het. Dit plaas ekstra druk op
produsente om hoër gehalte produkte te produseer.
Hierdie tesis ondersoek die gebruik van weging van die finale produk as ʼn hulpmiddel om
die operasionele effektiwiteit van die verpakking van tafeldruiwe te verbeter. Daar word
gekyk na die huidige toestand van die verpakking van tafeldruiwe in Suid-Afrika. Die
operasionele effektiwiteit van bestaande verpakkingstelsels word bepaal. Die meriete van
ʼn “weging van die finale produk stelsel” as bestuurshulpmiddel is nagevors. Daar word
ook bespreek of die stelsel as bestuurshulpmiddel aangewend kan word om die
effektiwiteit van huidige verpakkingstelsels te verbeter.
Produsente maak primêr gebruik van ongeskoolde arbeid om tafeldruiwe te verpak. Dit
maak dit moeilik om konstante goeie kwaliteit te lewer. Sommige verpakkingstelsels
begelei die operateur om bakkies van ʼn spesifieke massa te produseer. Sommige
verpakkingstelsels bevat ʼn interne toetsweeg funksie van een of ander aard. Alhoewel die
funksies die akkuraatheid, produkmassa en dus produkkwaliteit verbeter, kan menslike- en
masjienfoute steeds ʼn impak hê op die verpakkingsprosesse. Produsente maak gebruik
van interne kwaliteitsbeheerstelsels wat poog om menslike- en masjienfoute so gou
moontlik op te spoor en te herstel. Die PPECB, ʼn staatsliggaam, dwing die minimum Suid-Afrikaanse uitvoerstandaarde af
deur middel van inspekteurs wat lukraak produkte tydens produksie ondersoek. Indien die
produkte nie aan die kwaliteitstandaarde (insluitend massa) voldoen nie, moet die hele
pallet nagegaan word en die bakkies moet reggemaak word waar nodig, teen ʼn groot
onkoste vir die produsent.
Voorafverpakte produkte kan volgens die minimum- of gemiddelde-massa sisteme
geproduseer word. Die gemiddelde-massa sisteem verminder die hoeveelheid druiwe wat
weggegee word en verhoog dus inkomste, maar dit vereis dat elke bakkie met ʼn bepaalde
akkuraatheid geweeg moet word. Daar moet ook rekord gehou word van die massas.
Die byvoeging van geoutomatiseerde finale produk toetsweging het ʼn aansienlike
verbetering in die hoeveelheid oor- en ondermassa bakkies tot gevolg gehad. Dit het ook
die produktiwiteit van party verpakkingsstelsels verbeter. Daaropvolgende weër
eksperimente met ander opstellingsparameters het baie beter akkuraatheid getoon en dus
kon die hoeveelheid oor- en ondermassa bakkies selfs verder beperk word.
Met inagneming van die kostes daaraan verbonde om ʼn pallet oor te pak as gevolg van
ondergewig bakkies, sou dit selfs vir klein produsente die moeite werd wees om finale
produk toetsweging te implementeer. Dit het ʼn terugbetalingsperiode van minder as vyf
pakseisoene, afhangend van die produsent se spesifieke pakstooruitleg.
Nie alleen kan die implementering van finale produk toetsweging die risiko van ondergewig
produkte verlaag nie, maar dit kan ook nuwe markgeleenthede oopmaak vir gemiddeldemassa
produkte in ʼn baie kompeterende mark.
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