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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Packaging of table grapes for exports from SA : a comparative study

Nieuwoudt, 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
2

Resistance to airflow and moisture loss of table grapes inside multi-scale packaging

Ngcobo, 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
3

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.
4

Check weighing in table grape punnet packing: Opportunities in the development of operational effectiveness

Smit, 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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