Thesis (MScAgric) -- University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Postharvest berry split and abscission are prevailing physiological disorders that negatively impact on the quality of table grapes exported from South Africa. Inferior grape quality due to these disorders results in a considerable decline in consumer confidence in the branded product, which leads to a drop in demand, and consequently, lower prices. Since information concerning postharvest factors influencing postharvest berry split and abscission is limited, the search for reliable methods to adequately control these problems remains elusive. In an attempt to obtain the required information, the influence of harvest temperature, harvest maturity, perforated liners, field heat removal prior to packing, delay periods before and after packing, storage duration and the elevation of storage temperature on the development of berry split and abscission in 'Thompson Seedless' (Vitis vinifera Linnaeus) table grapes was investigated. Changes in abscission related factors during berry development, and the influence of pre-and postharvest ethylene inhibitors on the development of berry abscission in 'Waltham Cross' table grapes, was also studied. Berry split was aggravated by packing 'Thompson Seedless' grapes at high pulp temperatures of approximately 30°C, especially if the grapes were packed in non-perforated bags. The incidence of berry split could be reduced by between 80 and 90% by packing grapes in perforated instead of non-perforated liners. Perforated bags also reduced levels of S02 damage. However, due to significantly more moisture loss from grapes in perforated bags, compared to non-perforated bags, the risk of higher fruit and stem desiccation and softer berries existed. Optimum size and density of perforations needs to be determined to reduce berry split without excessive loss of moisture from the grapes, and S02gas from the air space surrounding the product. The influence of harvest temperature and liner type on berry abscission was not conclusive. Advanced maturity increased grape resistance to berry split. However, grapes harvested too mature were prone to stem desiccation and the development of Botrytis decay. The occurrence of berry abscission also appeared to increase with advanced harvest maturity. Consequently, to ensure optimal post-storage quality, 'Thompson Seedless' grapes should be harvested as soon as horticultural maturity has been reached, which appears to be at approximately 18°Brix. Field heat removal for 1.5 hours at 19°C prior to packing had no beneficial or adverse effect on berry split and abscission. Delay periods prior to packing aggravated berry abscission, but did not influence berry split significantly. Grapes delayed for 12 hours showed a significant increase in berry abscission and Botrytis decay, compared to grapes delayed for only 3 or 8 hours. Considering that the absence of fungal decay is the most important quality prerequisite in table grapes, it is of vital importance to pack grapes with as short a delay period as possible. Grapes packed in non-perforated liners and delayed for different durations after packing, before the onset of forced-air cooling (FAC), showed significant differences regarding the incidence of berry split. Grapes delayed for 18 hours had significantly higher levels of berry split directly after the delay period, compared to grapes delayed for 6 or 12 hours. No significant difference in berry abscission occurred between grapes delayed for different periods. To minimise the amount of berry split, FAC should be applied as rapidly as possible after the packing of grapes in non-perforated liners. Two storage related factors significantly influenced the incidence of berry split in 'Thompson Seedless' grapes during cold storage significantly, viz. the duration of storage at -O.soC,and the increase in temperature after low temperature storage. Berry split increased almost linearly with prolonged storage at -O.soC. An elevation of storage temperature from -O.soC to 10°C any time during the cold storage period, further aggravated the split problem. Consequently, the reduction of berry split in 'Thompson Seedless' table grapes during cold storage requires (a) the shortest possible cold storage period, and (b) good temperature management throughout distribution, from initiation of cooling until the final point of sale. The grape berry abscission potential, as quantitatively indexed by the measurement of the fruit removal force (FRF), showed significant changes during berry development of 'Waltham Cross' table grapes, from 27 to 111 days after full bloom (OAFB). This showed that at certain stages of fruit growth, 'Waltham Cross' grapes are more prone to berry abscission. At 27 OAFB, when the berries had an average diameter of 6.6mm, the grape bunches showed a significantly higher potential for berry abscission, compared to grapes sampled at a later stage. 'Waltham Cross' has inherently straggly bunches with bare shoulders. Therefore, any abscission during berry development will aggravate the problem. Consequently, it is of vital importance that any adverse factors such as moisture stress be avoided, especially during the period when 'Waltham Cross' grapes appear to be very susceptible to berry abscission. Of all parameters measured, moisture loss showed the best correlation with abscission. Grapes harvested with total soluble solids (TSS) of 12.3°Brix, 83 OAFB, had a significantly higher abscission potential than grapes harvested more mature. Therefore, by harvesting 'Waltham Cross' grapes at optimum maturity, at a TSS of approximately 16.4°Brix, berry abscission can be reduced to a great extent. It was evident that at veraison, the metabolism of grape berries changes drastically, and additional to the rapid increase in sugars and the rapid decrease in acidity, a decrease in FRF occurs. Preharvest sprays of ReTain™ (a derivative of aminoethoxyvinylglycine), which inhibits ethylene synthesis, showed no promise as a means to reduce postharvest berry abscission. A postharvest treatment with EthylBloc® (1-methylcyclopropene), which inhibits ethylene action, only reduced berry abscission during one season. / AFRIKAANSE OPSOMMING: Die fisiologiese defekte korrelbars en los korrels wat algemeen voorkom tydens opberging van sekere tafeldruif-kultivars, het 'n negatiewe invloed op tafeldruiwe wat uitgevoer word vanaf Suid-Afrika. Minderwaardige kwaliteit as gevolg van hierdie defekte het 'n aansienlike afname in verbruikers-vertroue tot gevolg wat aanleiding gee tot 'n ooreenkomstige afname in aanvraag en prys van die produk. Inligting rakende na-oes faktore wat die voorkoms van korrelbars en los korrels beïnvloed is beperk, en geen gewaarborgde metode bestaan om hierdie twee defekte volkome te beheer nie. In 'n poging om dié gewenste inligting te bekom, is ondersoek ingestel na die effek van oes-temperatuur, oes-rypheid, geperforeerde sakke, veldhitte verwydering voor verpakking, vertragingsperiodes voor en na verpakking, tydsduur van opberging, en die verhoging van die opbergingstemperatuur, op die voorkoms van korrelbars en los korrels by 'Thompson Seedless' (Vitis vinifera Linnaeus) druiwe. Daar is ook ondersoek ingestel na veranderings in afsnoering verwante faktore tydens korrel-ontwikkeling, en die invloed van vooren na-oes toedienings van etileen inhibeerders op die ontwikkeling van los korrels by 'Waltham Cross'tafeldruiwe. Korrelbars is vererger deur 'Thompson Seedless' met hoë pulptemperature van ongeveer 29.5°C te verpak, veral indien dit in 'n riie-geperforeerde sak verpak is. Die voorkoms van korrelbars kon tussen 80 en 90% verminder word deur 'Thompson Seedless' druiwe in geperforeerde sakke te verpak, in plaas van nie-geperforeerde sakke. Geperforeerde sakke het ook S02 skade op die druiwe verminder. Tog, as gevolg van betekenisvol meer vogverlies vanaf druiwe in geperforeerde sakke as vanaf druiwe in nie-geperforeerde sakke, bestaan die risiko van meer stingel-uitdroging en minder ferm korrels indien druiwe in geperforeerde sakke verpak word. Optimale grootte en digtheid van perforasies moet bepaal word om korrelbars te verminder, maar sonder oormatige vogverlies vanaf die druiwe en oormatige verlies aan S02. Die invloed van oes-temperatuur en sak-tipe op los korrels was nie oortuigend nie. Gevorderde oes-rypheid het die druif se weerstand teen korrelbars verhoog. Daarteenoor was druiwe wat té ryp geoes is, meer gevoelig vir stingel-uitdroging en Botrytis bederf. Dit wilook voorkom of die voorkoms van los korrels toeneem met gevorderde rypheid. Dus, om optimum kwaliteit na opberging te verseker, moet 'Thompson Seedless' geoes word sodra hortologiese rypheid bereik word, wat blyk om by 'n totale opgeloste vaste stof-inhoud (TOVS) van ongeveer 18°Brix te wees. Veldhitte verwydering voor verpakking, vir 1.5 uur by 19°C, het geen effek gehad op die voorkoms van korrelbars en los korrels nie. 'n Vertragingsperiode voor verpakking het die los korrel-probleem vererger, alhoewel dit geen betekenisvolle invloed op die voorkoms van korrelbars gehad het nie. Druiwe wat vir 12 uur voor verpakking vertraag is, het betekenisvol meer los korrels en Botrytis bederf getoon, in vergelyking met druiwe wat slegs 'n vertragingsperiode van 3 of 8 uur ondergaan het. Aangesien die afwesigheid van bederf die belangrikste kwaliteits-vereiste vir tafeldruiwe is, is dit van kardinale belang om druiwe so gou as moontlik na oes te verpak. Druiwe, verpak in nie-geperforeerde sakke, wat vir verskillende periodes vertraag is voor geforseerde-lug verkoeling, het betekenisvolle verskille getoon betreffende die voorkoms van korrelbars. Druiwe vertraag vir 18 ure voor verkoeling, het betekenisvol meer korrelbars getoon, soos gemeet onmiddellik na die vertragingsperiode, in vergelyking met druiwe wat slegs vir 6 of 12 ure vertraag was. Geen betekenisvolle verskille in los korrels het voorgekom tussen druiwe wat verskillende vertragingsperiodes ondergaan het nie. Om korrelbars te verminder, moet geforseerde-lug verkoeling so gou as moontlik na verpakking van druiwe in nie-geperforeerde sakke toegepas word. Twee opbergings-verwante faktore beïnvloed die voorkoms van korrelbars by 'Thompson Seedless' druiwe tydens koelopberging, naamlik die tydsduur van opberging by -O.soC,asook 'n styging in temperatuur vanaf -O.soC tot 1DoC. Korrelbars het feitlik liniêr toegeneem met verlengde opberging by -O.soC. 'n Styging in temperatuur vanaf -O.SoCtot 1DoCop enige tydstip gedurende die koelopbergingsperiode, het korrelbars verder vererger. Dus, om korrelbars by 'Thompson Seedless' tydens opberging tot die minimum te beperk, moet die tydsduur van opberging so kort as moontlik wees, en moet die koue ketting regdeur die distribusie-proses gehandhaaf word, vanaf inisiëring van verkoeling tot en met die uiteindelike verkoop van die produk. Die afsnoerings-potensiaal van druiwe, soos kwantitatief geïndekseer is deur meting van die vrug-verwyderings-vermoë (VVV), het betekenisvol verander gedurende korrel-ontwikkeling van 'Waltham Cross' tafeldruiwe, vanaf 27 tot 111 dae na volblom (DNVB). Dit het getoon dat 'Waltham Cross' druiwe by sekere stadiums van vrug-groei meer gevoelig is vir korrel afsnoering. By 27 DNVB, wanneer die korrels 'n gemiddelde deursnee van 6.6mm gehad het, het die druiwe 'n betekenisvolle hoër potensiaal vir afsnoering getoon, in vergelyking met druiwe wat op 'n latere stadium getoets is. 'Waltham Cross' is inherent geneig tot yl trosse met kaal skouers, gevolglik sal enige afsnoering tydens korrel-ontwikkeling die probleem vererger. Dus is dit van kardinale belang dat enige nadelige faktor, soos byvoorbeeld vogstres, vermy moet word, veral gedurende periodes wanneer dit wil voorkom of 'Waltham Cross' baie vatbaar is vir korrel afsnoering. Van al die parameters wat gemeet is, het vogverlies die beste korrelasie met korrel afsnoering getoon. Druiwe wat 83 DNVB, by 'n TOVS van 12.3°Brix geoes is, het 'n betekenisvol hoër potensiaal vir korrel afsnoering getoon, in vergelyking met druiwe wat ryper geoes is. Dus, deur 'Waltham Cross' druiwe by optimum rypheid te oes, by 'n TOVS van ongeveer 16.4°Brix, kan korrelbars in 'n groot mate verminder word. Tydens verelson, wanneer die metabolisme van die druiwe drasties verander, was daar gepaardgaande met die drastiese toename in TOVS en die drastiese afname in totale titreerbare sure (TSS), ook 'n afname in Voor-oes bespuitings met ReTain™, wat etileen sintese inhibeer, het geen potensiaal getoon om los korrels by 'Waltham Cross' te verminder nie. 'n Na-oes behandeling met EthyIBloc®, wat etileen werking inhibeer, het slegs korrel afsnoering in een van die seisoene effens verminder.

Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosch, 2007. / The South African and international table grape industries are growing rapidly, which necessitates the production of high quality export fruit at competitive production costs. For this reason, alternative irrigation methods are required to utilise water optimally while still attaining good quality table grapes. An increase in agricultural productivity may be dependent on either the availability of more water for irrigation or an increase in the efficiency of water use. The first aim of this study was to evaluate the effectiveness of the Partial Rootzone Drying (PRD) irrigation strategy in Crimson Seedless and Dauphine table grape production. This irrigation system is based on the drying of half of the vine roots, thereby allowing the plant to produce hormones like abscisic acid (ABA) in reaction to water stress. The hormone production in turn results in stomatal closure and the reduction of water loss via transpiration. The drying cycle is then repeated after 10 to 15 days on the other side of the vine, irrigating the previously dried roots. PRD will encourage a consistent production of the stress hormone abscisic acid (ABA), without actual water stress. This strategy reduces the amount of water used for irrigation, without an accompanying loss in fruit yield, as compared to conventional techniques. In this study, conventionally treated vines were irrigated according to historical block data and PRD-treated vines were irrigated at the same times. The second aim of this study was to monitor the efficacy of a foliar nutrient, Croplife. This foliar nutrient allegedly improves the uptake of foliar applied nutrients, assists with transport of all minerals through the leaves and enables the plant to attain higher pest and disease resistance thresholds. Conventionally treated vines that did not receive foliar nutrient treatment were compared to vines that received foliar nutrients as prescribed by the manufacturer. Vine cultivars Crimson Seedless and Dauphine, were grown under open hydroponic principles with drip and drip irrigation respectively in this experiment. For the hydroponic vines (Crimson Seedless), all vines were situated in the same row and 72 vines were divided into mini-plots of three vines. Treatments were then assigned to an equal number of plots at random. The same procedure was followed for the drip irrigated vines (Dauphine) but the vines were situated in two rows of equal length. Treatment effects were followed from budburst until harvest, where after post-harvest analyses were conducted. The first aim, namely to show that PRD is an effective irrigation strategy for table grape production in Crimson Seedless and Dauphine cultivars , has shown that vines did not exhibit signs of stress even though they received only half the conventional amount of water. This study was conducted over only one growth season and therefore no definite conclusions could be drawn about the long term effectiveness of PRD on table grapes. It did, however, confirm numerous results obtained from different studies on the use of PRD in wine grape production. The results obtained in the second part of the study were inconclusive and could not show that Croplife is effective in improving the uptake and transport of applied foliar nutrients. Because Crimson Seedless is cultivated under open hydroponic principles, nutrients can be absorbed by the roots via the soil and micronutrients are also available from chemical sprays during the season. There was no evidence to indicate that the use of Croplife increased nutrient absorption and transport, neither did it supplement or detract form the observed effect of PRD. Despite the limitations experienced during this study, it has shown that the use of PRD for table grape production may be a useful tool for improving water utilisation efficiency in future. The strategy will have to be developed systematically through experimentation to fully unlock the potential of the PRD management system for table grape production. This study provides a good starting point for future research required to elucidate numerous aspects of the PRD system and has clearly shown that established vineyards can be switched to a PRD system without a loss in table grape quality. It is envisaged that the advantages of this system could have a positive effect on the production of high quality fruit for the international market.

Thesis (MscAgric (Viticulture and Oenology))--University of Stellenbosch, 2006. / Under certain South African conditions, Redglobe develops a colour that is too dark and thus unacceptable for the Far Eastern markets. These markets require a pink colour instead of a dark red colour. The cultivation of grapes with an acceptable colour involves amongst other, canopy management practices. This generally includes the removal of leaves and/or lateral shoots. Hereby, the leaf area and the microclimatic conditions in the canopy are altered. The aim of this study was to test the usefulness of leaf and lateral shoot removal at different defoliation times after anthesis in order to obtain a pink coloured Redglobe crop. Other quality aspects, namely total soluble solids (TSS), total titratable acidity (TTA), berry mass and total yield, were also evaluated. A canopy management trial was conducted on six year old Redglobe vines with moderate vigour. The treatment design was a 2 x 3 x 4 factorial and involved two leaf removal (L) levels (L0 = 0% leaf removal; L33 = 33% leaf removal) in combination with three lateral shoot removal (LS) levels (LS0 = 0 % lateral shoot removal; LS50 = 50% lateral shoot removal; LS100 = 100% lateral shoot removal). Four defoliation times (DT) were selected: 36 (pea berry size), 69 (véraison), 76 (one week after véraison) and 83 (two weeks after véraison) days after anthesis (DAA). A total of 24 treatment combinations, replicated in four blocks, were applied. Generally, treatment combinations involving 33% leaf removal lowered the main shoot leaf area. Likewise, the lateral shoot leaf area was decreased by increasing levels of lateral shoot removal at any defoliation time. As expected, 33% leaf removal applied in combination with any level of lateral shoot removal, always resulted in a lower total vine leaf area compared to where 0% leaf removal was part of the treatment combination. Compensation reactions occurred and in this regard the main shoot leaf size increased due to 33% leaf removal applied at 1 week after véraison and 2 weeks after véraison. Treatment combinations involving lateral shoot removal increased the ratio of main shoot leaf area to the total leaf area. On the other hand, the main shoot leaf area percentage was lowered by the application of 33% leaf removal at 2 weeks after véraison compared to no leaf removal at the same defoliation time. It can therefore be assumed that the contribution of lateral shoot leaves to grape composition might have increased in cases where the main shoot leaf area was lowered at a later stage (e.g. 2 weeks after véraison). The bunches were visually evaluated and divided into classes from dark (class one) to light (class nine). This visual bunch evaluation showed that the mean bunch colour was in class three (lighter than class two) due to the defoliation time. The lateral shoot removal x leaf removal interaction resulted in a mean bunch colour that was in classes 2 and 3. However, within these classes, there was a tendency that bunch colour decreased for defoliation times later than pea berry size. The lateral shoot removal x leaf removal interactions showed that bunch colour was darker when the treatment combinations involved 0% leaf removal. The percentage of bunches with the desired colour was increased by application of the treatments at véraison, compared to the other defoliation times, and also with 50% lateral shoot removal and 100% lateral shoot removal compared to 0% lateral shoot removal. Biochemical analyses confirmed that increased levels of lateral shoot removal generally lowered the anthocyanin concentration regardless of defoliation time. A similar effect on TSS was observed, i.e. from véraison onwards, the application of 50% lateral shoot removal and 100% lateral shoot removal tended to lower TSS. The effect of these levels of lateral shoot removal at véraison was significant. The role of the lateral shoots in colour development and sugar accumulation is therefore emphasized. Furthermore, the special role that lateral shoots also play in berry development is illustrated in that berry mass tended to decrease when 100% lateral shoot removal in combination with 33% leaf removal and 100% lateral shoot removal in combination with 0% leaf removal were applied at véraison. This, together with the positive relationship obtained between grape colour and the lateral shoot leaf area:fruit mass ratio, accentuates the role of active leaf area during the ripening period. The possible effect of the microclimatic light environment on colour must also be considered. However, although the light intensity increased with increased levels of LS, the colour that was obtained was probably not associated with the differences in light intensity. It was found that it is possible to manipulate the colour of Redglobe grapes with defoliation treatments. However, the treatments that have a decreasing effect on grape colour also affected other quality parameters like TSS and berry size negatively. Although, it is possible to reduce the colour of Redglobe through the application of leaf and lateral shoot removal at different defoliation times, the question arises whether the treatment combinations used in this study are worthwhile to pursue because the mean bunch colour that was obtained was still too dark. However, it was possible to increase the percentage of bunches with the desired colour. Therefore, if such treatments are applied, it must be approached cautiously, keeping in mind that assimilate supply has to be sustained throughout the ripening period.

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

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

Thesis (MscAgric (Horticulture))--University of Stellenbosch, 2007. / More and more markets develop around the world for South African grapes and it becomes a challenge to store grapes for longer and reach the market with superior quality. The most destructive decay fungus, Botrytis cinerea can cause huge economic losses and successful postharvest control in the table grape industry relies on SO2. This gas not only controls the fungus but also causes losses due to phytotoxicity. SO2 also creates allergic reactions amongst certain people. In modern times the focus is on food safety and governments consequently impose certain regulations and restrictions to restrict the use of chemicals and ensure “cleaner” produce. The objective of this study was to find a steriliser to reduce B. cinerea inoculum on the berry surface prior to storage,to be used in conjunction with the current method of control – the SO2 generator pad.

Thesis (MScAgric (Conservation Ecology and Entomology)--University of Stellenbosch, 2005. / The South African table grape industry exports approximately 60% of the table grapes produced. A major threat to the export of these grapes is the phytosanitary risk that insect pests pose. This study was conducted in the Hex River Valley, South Africa’s main table grape producing area. The aim of this study was to reduce the number of phytosanitary rejections from insects on table grapes from the Hex River Valley. Thus the main objectives of the study were to identify the most important phytosanitary pests in the Hex River Valley; the determination of their presence in the vineyards with possible means to control them; and to assess the possibility of using postharvest quarantine treatments in the Western Cape. Further aims were to determine the effect of different colour harvesting crates on the phytosanitary pests and whether the phytosanitary pests infested the grapes via packhouses. The most important phytosanitary pests of table grapes of the Hex River Valley are in order of importance: Phlyctinus callosus (Schonherr) (Coleoptera: Curculionidae), Epichoristodes acerbella Walker (Lepidoptera: Tortricidae), Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), Gonocephalum simplex Fabricius (Coleoptera: Tenebrionidae) and Dysdercus fasciatus Signoret (Hemiptera: Pyrrhocoridae). 12.71% of rejections were from species that were not identified, while a further 33% of the rejections were possibly identified incorrectly. Phytosanitary control of P. callosus appeared to be far more effective using Plantex® than pesticides. Weather conditions appeared to affect the abundance of P. callosus, especially warm weather, while bunches harboured less P. callosus later in the day. Control of E. acerbella with DiPel® (Bacillus thuringiensis var. kurstaki) appeared to at least reduce the population within the vineyards, and so its use is recommended. P. ficus is a non-actionable species for the USA market and is not listed as a phytosanitary pest for the Israeli market and so should not be causing any phytosanitary rejections. C. capitata appeared to be successfully controlled by the fruit fly sterile release program and the cold sterilisation it currently undergoes. G. simplex caused few rejections. It is still unclear where this pest infests the grapes, as it was found in both the field and in the packhouses. D. fasciatus occurrence on grapes was probably accidental. It was shown that picking during the early and late parts of the day, when this species was less active, reduced its occurrence in bunches. Gryllus bimaculatus (De Geer) (Orthoptera: Gryllidae), although not reported as a reason for rejections in table grapes for the past two years, was an actionable species that was present in large numbers in the Hex River Valley. There was a strong correlation between increasing quantities of pesticides and higher abundances of G. bimaculatus. It appeared to be an indicator of the overuse of pesticides. Results of this study showed that infestation by the phytosanitary pests came from neighbouring vineyards. The creation of barriers to prevent the movement of these pests between vineyards is suggested. Methyl bromide is the most commonly used postharvest quarantine treatment. Owing to the ozone-depleting properties of methyl bromide, it is scheduled to be outlawed in many countries from 2005. Alternative postharvest treatments are irradiation, extreme temperatures, forced air, vapour-heat treatments and the use of controlled atmospheres. Irradiation treatments appeared to control the pests at doses that do not damage the grapes. Controlled atmosphere treatments also have a high probability of success, although more research is required on this treatment. Low temperature treatments are relatively cheap as most exported fruit already undergoes cold storage, and appears to control species in the families Pseudococcidae and Tephritidae, although further research is required for the other pest. Colour or location of the harvesting crates in the vineyards appeared not to influence the number of phytosanitary pests collected, as they were not attracted to these crates.

Thesis (MscAgric (Viticulture and Oenology))--Stellenbosch University, 2008. / The South African table grape industry is under great pressure to produce table grapes of the best quality for the export markets. Quality defects such as poor colour, inadequate berry firmness, browning and soft tissue breakdown cause great losses in export. The firmness of table grapes is one of the major factors determining the eating quality of grapes. Consumers prefer grapes with a firmer flesh above those with soft flesh. Firmer berries are commonly accepted to have better eating quality and longer cold storage capacity. Factors that promote and maintain berry firmness are only speculated about; therefore producers cannot effectively control the development of firmer berries by managerial practises or by applying specific sprays. The study was done on Redglobe and two Waltham Cross clones (the firmer Clone 8 and softer Clone 13). The aim of this study was two-fold. Firstly the cellular and ultracellular differences between the tissues of firm and soft berries were determined. The effect of gibberellic acid (GA3), synthetic cytokinin (CPPU) and bunch applied calcium sprays on the cellular and ultracellular structure of berry tissues were also under investigation. Secondly, the effects of GA3, CPPU and bunch directed calcium sprays on berry firmness, eating quality and storage capacity were determined. To determine the cellular and ultracelular structure of berry tissues, light microscope (LM) and transmission electron (TEM) studies were done. In order to investigate the effect of different sprays on berry firmness, 20 mg/L GA3 (GA3 treatment) was applied at 10mm average berry size; 20 mg/L GA3 plus 3 mg/L CPPU (CPPU treatment) was applied at 10 mm average berry size; and a mixture of 8 L/ha Stopit® and 5 L/ha Caltrac® (calcium treatment) was applied directly to the bunches every two weeks from berry set till veraison for the calcium treatments. The control received no plant bioregulators (PBR’s). The treatments were the same for both cultivars. Grapes were stored three weeks at 0 °C and one week at 10 °C after which it was evaluated for loose berries, botrytis infections, rachis browning and berry split. Afterwards it was tasted by an independent tasting panel. Firm berries were found to have an opaque coloured flesh while soft berries had a gel-like translucent flesh. For berries with normal firmness, the opaque flesh is limited to the outer mesocarp of the berry. Extremely firm berries’ whole mesocarp consisted of the opaque coloured flesh while soft berries’ mesocarp consisted of mostly the gel-like translucent flesh with, in some cases, a very thin layer of opaque flesh just under the skin. Berry firmness was not related to cell size as the cell size of the tissues in the firm and soft berries were identical. Cell shape seems to play an important role in berry firmness. The cells in the opaque coloured flesh of the outer mesocarp are more turgid and oval than those in the gel-like flesh of the inner mesocarp. Berry firmness is therefore determined by the thickness of the outer mesocarp with the opaque coloured flesh that contains turgid cells. The thickness of cell walls between the different tissues did not differ. There was however a difference between the cell contents and the plasmalemmas of the inner and outer mesocarp. The plasmalemma and tonoplast of the outer mesocarp cells was more intact than those of the inner mesocarp. The membranes in the inner mesocarp are more subtracted form the cell wall than in the outer mesocarp. Both the PBR’s and calcium treatments cause a delay in sugar accumulation in the case of Redglobe and Waltham Cross. The CPPU treatment results in significantly bigger and firmer berries for both cultivars. In the case of Redglobe, this treatment cause bigger cells in the outer mesocarp suggesting a correlation between berry firmness and cell size. In the case of Waltham Cross, however, cell size did not play a role in berry size and firmness; instead the rate of cell division earlier in berry development. The CPPU treatment was the only treatment that maintains berry firmness during cold storage for Redglobe while GA3 and CPPU did so in the case of Waltham Cross. PBR’s seems to have no effect on cell wall thickness. In the case of Redglobe, the calcium treatments resulted in significantly thinner cell walls, but this can not be explained. Calcium and GA3 treatments had a negative effect on grape quality after cold storage of both Redglobe and Waltham Cross. The Waltham Cross CPPU treatment results in better taste and colour as observed by the tasting panel, while in the case of Redglobe, the tasting panel preferred the control. It is found that the use of CPPU in combination with GA3 had the best effect on the eating quality, storage capacity, berry size and firmness. When a producer decides to use the CPPU treatment in order to improve berry firmness, he must realize that it can cause delayed ripening which can affect the export of the fruit.

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.

Thesis (MCom)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: “Within the context of the current market conditions, SCF may be one of the most attractive tools for companies to diversify funding basis, enrich and solidify their relationships with suppliers and their core banks.” – Michiel Steeman (Executive Director – Supply Chain Finance Community). (ING Group, 2013b). Insufficient cash flow is one of the major reasons for business failure in the current business environment. The spotlight is on collaboration between supply chain management and finance to release tied up cash in supply chains. Supply Chain Finance is a financial tool to help improve cash flow and optimise working capital to operate more efficiently. South Africa is one of the leading fruit exporters in the world with complex supply chains and even more complex financial arrangements. The need for Supply Chain Finance is aggravated by the long distances to overseas markets, and thus the long delay in payments after goods have been shipped. Supply Chain Finance is beneficial to the supplier, buyer and the financial service provider, creating a win-win-win situation. During this research the table grape export supply chain of Denau Farming is investigated to develop an explorative case study to implement Supply Chain Finance into their business model. During the research the problem of late payment received by buyers is explored by means of interviews and existing literature. A Concept Model is developed by adapting the Supply Chain Operations Reference Model (SCOR®) and the Management for Supply Chains (M4SC™) framework to identify the supply chain strategy during the current as-is physical and financial flow and to identify the gap in the supply chain. Two Supply Chain Finance solutions are identified based on Denau Farming’s financial needs in order to develop the to-be physical and financial supply chains and the resource changes required to facilitate the respective implementation. The final result determines how the proposed Supply Chain Finance solutions affect the expected cash-to-cash cycle time and the expected Economic Value Added (EVA®) in the case study. / AFRIKAANSE OPSOMMING: “Within the context of the current market conditions, SCF may be one of the most attractive tools for companies to diversify funding basis, enrich and solidify their relationships with suppliers and their core banks.” – Michiel Steeman (Executive Director – Supply Chain Finance Community). (ING Group, 2013b). Onvoldoende kontantvloei is een van die vernaamste redes waarom besighede in die huidige sakeomgewing misluk. Die kollig val op samewerking tussen voorsieningskettingbestuur en finansiering om kontant wat vasgevang is in voorsieningskettings te kan vrystel. Voorsieningsketting-finansiering is ‘n finansiële instrument wat kan help om kontantvloei verbeter en bedryfskapitaal te optimeer om meer doeltreffend te bedryf. Suid Afrika is een van die voorste vrugte-uitvoerders in die wêreld met komplekse voorsieningskettings en nog meer komplekse finansiële reëlings. Die behoefte vir voorsieningskettingbestuur-finansiering word vererger deur die lang afstande na oorsese markte, en dus die lang vertraging vir betaling nadat goedere reeds verskeep is. Voorsieningsketting-finansiering is voordelig vir die verskaffer, koper, en die finansiële diensverskaffer deur die skep van ‘n wen-wenwen situasie. As deel van hierdie navorsing is die tafeldruif-uitvoer voorsieningsketting van Denau Boerdery ondersoek as deel van die ontwikkeling van ‘n verkennende gevallestudie om sodoende voorsieningsketting-finansiering in hul sake-model te implementeer. Tydens die navorsing is die problem van laat betaling ontvang vanaf kopers in oorsese markte verder ondersoek deur middel van onderhoude en bestaande literatuur. ‘n Konsep model is ontwikkel deur die toepassing en aanpassing van die Supply Chain Operations Reference Model (SCOR®) en die Management for Supply Chains (M4SC™) raamwerk beginnende met die identifisering van ‘n voorsieningskettingstrategie tydens die huidige fisiese en finansiële vloei en die begin van ‘n gapings-identifisering vir die voorsieningsketting. Twee voorsieningsketting-finansiering oplossings is geidentifiseer gebaseer op Denau Boerdery se finansiële behoeftes en die ontwikkeling van ‘n verwagte toekomstige fisiese en finansiële voorsieningsketting asook die hulpbronveranderinge benodig wat die onderskeie implementerings kan help fasiliteer. Die finale navorsingsresultate bepaal tot watter mate die voorgestelde voorsieningsketting-finansiering oplossings die verwagte kontant-tot-kontant siklustyd asook die verwagte Ekonomiese Waarde Toevoeging (EVA®) in die gevallestudie beïnvloed.