+publisher:"Stellenbosch University" +contributor:("Huysamer, M.")

Stellenbosch University

1. Matsikidze, Stenford Ngonidzashe. Feasibility of closed ventilation and automatic ventilation for sea freight of Proteaceae cut flower stems.

Degree: MScAgric, Horticulture, 2018, Stellenbosch University

URL: http://hdl.handle.net/10019.1/103857

► ENGLISH ABSTRACT: Global trends aimed at advancing sea freight technology and reducing carbon emissions have led to the invention of automated reefer technologies. This development… (more)

▼ ENGLISH ABSTRACT: Global trends aimed at advancing sea freight technology and reducing carbon emissions have led to the invention of automated reefer technologies. This development brings the challenge of having to determine product physiological limits that are vital for the implementation of automatic ventilation technology on South African produced Proteaceae cut flower stems. A study was conducted to determine the respiration rates, lower O2 limits and CO2 toxicity tolerance limits of Proteaceae cut stems in order to assess the feasibility of using automatic ventilation (AV+) vs. conventional fixed open-air exchange (AirEx) ventilation shipping of Proteaceae cut stems. In a closed ventilation system (representing unvented conditions as is possible with AV+ technology) which contained a mixed load of Proteaceae products in 45-55 % free air, it was observed that the O2 level fell to approximately 8.5 % whilst the CO2 level rose to about 10 %, when a HarvestWatch™ dynamic controlled atmosphere (DCA) system was used for gas sampling. Using a handheld gas analyser as an alternative sampling method revealed that under these conditions O2 levels fell below 2 %, and CO2 levels rose to above 17 %. Although the O2 dropped considerably, it was still above the Lower Oxygen Limit (LOL), which ranged from 0.09-0.33 % O2, 0.08-0.41 % O2 and 0.08-0.48 % O2 for Leucadendron, Leucospermum and Protea products respectively. At 5 ℃, the respiration rates were between 15.11-48.07 mL CO2.kg-1.h-1 for Leucadendron, 19.06-45.44 mL CO2.kg-1.h-1 for Leucospermum and 10.76-27.24 mL CO2.kg-1.h-1 for Protea. Closed ventilation, low O2 and high CO2 atmospheres generally resulted in mass loss that was lower than or comparable to AirEx. The inflorescence and leaf colour changes in Proteaceae products stored in closed ventilation, low O2 and high CO2 treatments were commercially not significant. There were no signs of low O2 and/or high CO2 damage on the stems stored under closed ventilation. The inflorescence and leaf visual quality of Proteaceae products stored in closed ventilation was generally better than that of stems stored in AirEx. Leucadendron, Leucospermum and Protea stems stored in high CO2 treatments had comparable or better quality than stems stored in AirEx. However, exposure to 15 % CO2 for 21 d reduced longevity of some products. In Leucadendron, the response to AirEx, DCA and 2 % O2 on flower head visual quality was variable and the treatments were equally effective in maintaining leaf visual quality. Flower and leaf visual quality and longevity was comparable between the AirEx and low O2 treatments in Leucospermum and Protea. Monosaccharides plus oligosaccharides were the most abundant sugars, followed by polysaccharides, and starch was the least abundant in Leucadendron, Leucospermum and Protea stems. Differences in polysaccharide and starch content were minor, between AirEx and low O2 treatments, also between AirEx and high CO2 treatments. Lipid peroxidation was comparable between AirEx and high CO2 atmospheres. The AirEx,… Advisors/Committee Members: Hoffman, E. W., Huysamer, M., Botes, A., Stllenbosch University. Faculty of Agrisciences. Dept. of Horticulture..

Subjects/Keywords: Closed ventilation shipping; Freight shipping of Proteaceae cut flowers; Automatic ventilation technology; UCTD

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APA (6^th Edition):

Matsikidze, S. N. (2018). Feasibility of closed ventilation and automatic ventilation for sea freight of Proteaceae cut flower stems. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/103857

Chicago Manual of Style (16^th Edition):

Matsikidze, Stenford Ngonidzashe. “Feasibility of closed ventilation and automatic ventilation for sea freight of Proteaceae cut flower stems.” 2018. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/103857.

MLA Handbook (7^th Edition):

Matsikidze, Stenford Ngonidzashe. “Feasibility of closed ventilation and automatic ventilation for sea freight of Proteaceae cut flower stems.” 2018. Web. 15 Dec 2019.

Vancouver:

Matsikidze SN. Feasibility of closed ventilation and automatic ventilation for sea freight of Proteaceae cut flower stems. [Internet] [Masters thesis]. Stellenbosch University; 2018. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/103857.

Council of Science Editors:

Matsikidze SN. Feasibility of closed ventilation and automatic ventilation for sea freight of Proteaceae cut flower stems. [Masters Thesis]. Stellenbosch University; 2018. Available from: http://hdl.handle.net/10019.1/103857

Stellenbosch University

2. Van Hoorn, A. T. (Aaltje Trientje). Optimisation of blueberry postharvest handling and storage.

Degree: MScAgric, Horticulture, 2004, Stellenbosch University

URL: http://hdl.handle.net/10019.1/20906

► ENGLISH ABSTRACT: By world standards South Africa’s contribution to fresh blueberry production is very small, a mere 0.25 %. This seemingly insignificant and unimpressive statistic… (more)

▼ ENGLISH ABSTRACT: By world standards South Africa’s contribution to fresh blueberry production is very small, a mere 0.25 %. This seemingly insignificant and unimpressive statistic is, however, by no means indicative of the impending impressive potential the South African blueberry industry holds. South Africa is encountering a rapid growth phase off a very small base and the current 100-150 ton export crop is expected to increase to a range of 500 to 600 tons or more in the next five years. Consequently, export by sea must be considered as a logistic alternative. Seafreight success relies on controlled atmosphere storage which in turn relies on berries of exceptional quality. To achieve this, fundamental differences between blueberry cultivars must be examined and blueberry handling and storage regimes must be assessed and optimised. This study investigates the storage potential of certain rabbiteye blueberries relative to controlled atmospheres and short pre-cooling delays. Quality assessments were based on external colour, soluble solids, titratible acidity, firmness and decay development. Furthermore, the respiration and ethylene production rates as well as moisture loss, of various cultivars were determined to characterize fundamental differences amongst cultivars and to gain insight into their postharvest behaviour. Lastly the effect of infection on pigment levels of blueberry flesh and peel was examined for the purpose of laboratory experience. Controlled atmosphere storage had the greatest impact on berry firmness and percentage decay. No off flavours were detected during sensory analysis at the CA levels tested. CAstored berries were firmer and incidence of decay was reduced significantly. Significant decay reduction was challenged by the market tolerance of no more than 2 %. Decay suppression and storage extension was insufficient (for the set period), particularly after the shelf life period. Cultivar and seasonal differences as well as picking maturity and inoculum pressure determine blueberry CA storability. CA may be a valuable technology, however advances must first be made in ensuring optimal blueberry quality to warrant export by sea. Short pre-cooling delays (0, 2, 4, 6 h) at 20 ºC had no effect on colour (L, C, H), total soluble solids, titratable acidity and firmness of blueberry cultivars, ‘Centurion’, ‘Premier’ and ‘Tifblue’. Results for percentage decay indicate that prompt cooling becomes more critical as the duration of storage increases, particularly when market specification of no more than 2 % decay must be met. Berries subjected to longer delays appear to be more susceptible to decay. Differences exist among cultivars and knowledge gained from this research can be used to adapt handling and cooling regimes. Information generated will benefit cultivar selection for marketing (local vs. export), storage (short vs. long term) and logistics (air vs. seafreight). Rabbiteye blueberry cultivars differ considerably in terms of their respiration rate, ethylene… Advisors/Committee Members: Huysamer, M., Jacobs, G., Stellenbosch University. Faculty of Agrisciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture; Dissertations – Horticulture

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APA (6^th Edition):

Van Hoorn, A. T. (. T. (2004). Optimisation of blueberry postharvest handling and storage. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/20906

Chicago Manual of Style (16^th Edition):

Van Hoorn, A T (Aaltje Trientje). “Optimisation of blueberry postharvest handling and storage.” 2004. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/20906.

MLA Handbook (7^th Edition):

Van Hoorn, A T (Aaltje Trientje). “Optimisation of blueberry postharvest handling and storage.” 2004. Web. 15 Dec 2019.

Vancouver:

Van Hoorn AT(T. Optimisation of blueberry postharvest handling and storage. [Internet] [Masters thesis]. Stellenbosch University; 2004. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/20906.

Council of Science Editors:

Van Hoorn AT(T. Optimisation of blueberry postharvest handling and storage. [Masters Thesis]. Stellenbosch University; 2004. Available from: http://hdl.handle.net/10019.1/20906

Stellenbosch University

3. Ngcobo, Mduduzi E. K. Cooling and shipping studies on table grapes (Vitis vinifera L.).

Degree: MScAgric, Horticulture, 2008, Stellenbosch University

URL: http://hdl.handle.net/10019.1/21440

► ENGLISH ABSTRACT: Fruit quality is the most important factor that determines prices for the fruit in the international markets. Although different consumers perceive quality differently… (more)

▼ ENGLISH ABSTRACT: Fruit quality is the most important factor that determines prices for the fruit in the international markets. Although different consumers perceive quality differently there are quality variables that are always associated with poor quality by all consumers. In table grapes (Vitis vinifera L.) these variables may include overall appearance, stem condition, SO2 damage, decay, berry browning and shatter. The presence of these quality defects negatively affects prices and most often results in quality claims. Cooling is the most widely used method to reduce the postharvest loss of fruit quality. In South Africa, most deciduous fruits including table grapes are forced air cooled to a statutory pulp temperature of –0.5°C prior to shipping in an effort to preserve quality, thus ensuring good market prices for the fruits. Despite these efforts, there are still quality claims from the markets and this reduces the returns to the growers. The objectives of this research were to: (i) see if cooling time can be reduced by cooling to higher pulp temperatures of 1.5°C and 3°C without causing quality losses, thus improving the throughput of the cold rooms; (ii) see if the problem of berry browning can be alleviated by cooling grapes to higher pulp temperature, and (iii) see whether pallet positioning in the cooling tunnels and reefer container affect quality. The trends showed better quality when ‘Victoria’ and ‘Regal Seedless’ were forced air cooled (FAC) to pulp temperatures of 1.5 °C and 3 °C as opposed to –0.5 °C. There were no economic losses associated with pre-cooling grapes to pulp temperatures of 1.5 °C and 3 °C. There were no significant differences in berry browning related to pre-cooling treatments. However, cooling time was reduced significantly. In most of the cooling tunnels and reefer containers used in this trial, grape quality results showed no significant differences between the positions in the stack and in reefer containers. However, in cases where there were significant differences, the middle and the rear positions showed better grape quality in terms of stem condition (dry and brown stems) than the front position (near fan) in both the pre-cooling stack and reefer containers. The trends showed that the front is cooler than the back of the pre-cooling stack. The pulp temperature differences between the front and rear positions in the reefer container were as high as 1.23 °C. The trends also showed that the bottom layers of the pallets were cooler than the top layers in the reefer container. FAC to 3°C resulted in a constant reduction in percentage electrolyte leakage after 4 weeks of storage at –0.5°C, while FAC to 1.5°C, -0.5°C and static room cooling (control) in some cases showed an initially low electrolyte leakage followed by an increase in leakage after 4 weeks of storage. FAC grapes to higher pulp temperatures of 3°C and 1.5°C could reduce the cooling time, thereby improving the throughput of cold rooms. There was no clear evidence to suggest that… Advisors/Committee Members: Huysamer, M., Jacobs, G., Stellenbosch University. Faculty of AgriSciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture; Dissertations – Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ngcobo, M. E. K. (2008). Cooling and shipping studies on table grapes (Vitis vinifera L.). (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/21440

Chicago Manual of Style (16^th Edition):

Ngcobo, Mduduzi E K. “Cooling and shipping studies on table grapes (Vitis vinifera L.).” 2008. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/21440.

MLA Handbook (7^th Edition):

Ngcobo, Mduduzi E K. “Cooling and shipping studies on table grapes (Vitis vinifera L.).” 2008. Web. 15 Dec 2019.

Vancouver:

Ngcobo MEK. Cooling and shipping studies on table grapes (Vitis vinifera L.). [Internet] [Masters thesis]. Stellenbosch University; 2008. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/21440.

Council of Science Editors:

Ngcobo MEK. Cooling and shipping studies on table grapes (Vitis vinifera L.). [Masters Thesis]. Stellenbosch University; 2008. Available from: http://hdl.handle.net/10019.1/21440

Stellenbosch University

4. Kapp, Anine A. C. Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature.

Degree: MScAgric, Horticulture, 2008, Stellenbosch University

URL: http://hdl.handle.net/10019.1/21447

► ENGLISH ABSTRACT: Stone fruit is susceptible to chilling injury and intermittent warming has been shown to alleviate chilling injury during cold storage. A dual temperature… (more)

▼ ENGLISH ABSTRACT: Stone fruit is susceptible to chilling injury and intermittent warming has been shown to alleviate chilling injury during cold storage. A dual temperature storage regime was developed in South Africa for plums based on the principles of intermittent warming. The regime consists of an initial period at -0.5°C, a variable duration warming period at 7.5°C, followed by -0.5°C. Refrigerated integral containers were designed to maintain product temperature and not to reduce product temperature, per se. Considering that dual temperature shipment requires significant refrigeration and effective distribution of cool air to remove sensible- and respiratory heat, the capacity of integral containers to ship plums successfully at dual temperature is questioned. The objectives of this study were, firstly, to analyse pulp temperature data and possibly identify different temperature zones within containers shipping plums at dual temperature. Secondly, to understand the underlying processes differentiating the temperature zones and thirdly, to determine the effect of container performance on fruit quality. Three processes were identified as important characteristics of pulp temperature data sets recorded during dual temperature shipping, namely cooling down, heating up and over heating in the container. The order of importance differed according to the cultivar shipped and the container’s performance. Three temperature zones were identified in dual temperature containers, where the average pulp temperature, time to heat up and time to cool down for each temperature zone increased along the length, across the width from the left to the right and up the container system. The variable temperature conditions were possibly due to a variation in delivery air temperature, poor airflow and the effect of increased respiration and, therefore, production of vital heat by the fruit. The cooling down process was identified as the most important process discriminating the temperature zones. With the exception of ‘Fortune’, variable temperature conditions found within integral containers shipping plums at dual temperature had a significant influence on the fruit firmness post-shipment, where deterioration levels increased from the front to the door end of the container due to an increase in pulp temperature. However, it was also shown that fruit firmness prior to shipment could have a determining effect on differences found. It could not be proven that variable temperature conditions resulted in significantly higher levels of internal defects within the integral container. Temperature zones could not be identified within refrigerated integral containers shipping plums at single temperature, suggesting that the containers are able to maintain the temperature well throughout the container area. A constant 2°C storage temperature could possibly replace the commercial dual temperature regime in the case of ‘Pioneer’ plums due to improved fruit firmness, similar colour development to the control and… Advisors/Committee Members: Huysamer, M., Jacobs, G., Theron, K. I., Stellenbosch University. Faculty of AgriSciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture; Dissertations – Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kapp, A. A. C. (2008). Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/21447

Chicago Manual of Style (16^th Edition):

Kapp, Anine A C. “Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature.” 2008. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/21447.

MLA Handbook (7^th Edition):

Kapp, Anine A C. “Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature.” 2008. Web. 15 Dec 2019.

Vancouver:

Kapp AAC. Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature. [Internet] [Masters thesis]. Stellenbosch University; 2008. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/21447.

Council of Science Editors:

Kapp AAC. Evaluation of temperature variances found with integral reefer containers during shipment of Japanese plums (Prunus salicina Lindl.) at dual and single temperature. [Masters Thesis]. Stellenbosch University; 2008. Available from: http://hdl.handle.net/10019.1/21447

Stellenbosch University

5. Laubscher, Nicolaas Johannes. Pre- and post harvest factors influencing the eating quality of selected Nectarine (Prunus persica (L.) Batsch ) cultivars.

Degree: Horticulture, 2006, Stellenbosch University

URL: http://hdl.handle.net/10019.1/2718

►

Thesis (MscAgric (Horticulture)) – University of Stellenbosch, 2006.

Fruit quality, and especially eating quality, of nectarines has become very important to markets and consumers in recent… (more)

▼

Thesis (MscAgric (Horticulture)) – University of Stellenbosch, 2006.

Fruit quality, and especially eating quality, of nectarines has become very important to markets and consumers in recent years. Pre- and post harvest factors that influence the eating quality of nectarines were studied to optimise fruit quality at harvest and to maintain this quality during export. This will ensure good returns for a producer and will maximise his profit. The influence of the variables canopy position, initial fruit size and bearing position was studied to determine the variation in fruit quality within a nectarine tree. ‘Red Jewel’ and ‘Ruby Diamond’ fruit from the upper part of the tree canopy had significantly higher total soluble solids (TSS). Fruit position on the shoot does not seem to play a significant role in fruit quality for ‘Red Jewel’ nectarines, which will allow producers to leave more than one fruit per bearer if necessary. Fruit thinning is an important means to improve fruit size and quality in ‘Red Jewel’, but poor thinning can cause extreme variability in size and quality. Fruit that were small at thinning remained significantly smaller, weighed less, had lower sugars and higher acids at harvest. If it is possible to reduce the variation in size at thinning, fruit will be much more homogenous at harvest. The effect of pre-conditioning (PC) prior to storage and controlled atmosphere (CA) storage was evaluated on ‘Red Jewel’ and ‘Spring Bright’ nectarines. Free juice percentage was determined at the end of a simulated export protocol. The severity of woolliness differed between the two seasons for both nectarine cultivars. PC, to a firmness of 6 kg, followed by regular atmosphere (RA) storage increased percentage free juice significantly in ‘Spring Bright’ and ‘Red Jewel’ nectarines. However, a PC protocol for each cultivar and each producer must be determined beforehand to ensure fruit quality. CA storage is another technique that can be used to prevent the development of chilling injury (CI) symptoms. Both ‘Spring Bright’ and ‘Red Jewel’ showed an increase in percentage free juice with the use of CA storage during both seasons.The eating quality of nectarines depends on the composition of the individual sugars and organic acids and the ratio between them. Sucrose, fructose, glucose and sorbitol were found to be the major sugars in all evaluated nectarine cultivars. Sucrose was the dominant sugar in all cultivars at optimum maturity. The three main organic acids in nectarine cultivars were malic, citric and quinic acid, with malic acid being dominant at optimum maturity. Small amounts of shikimic, fumaric and succinic acid were also observed. It was evident that cultivars differ in the composition of sugar and organic acids at optimum maturity, especially the standard acid cultivars and the new low-acid cultivars. Individual sugars and organic acids in cultivars also differ in how they react during storage.

Advisors/Committee Members: Theron, K. I., Huysamer, M., University of Stellenbosch. Faculty of Agrisciences. Dept. of Horticulture..

Subjects/Keywords: Agriculture

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APA (6^th Edition):

Laubscher, N. J. (2006). Pre- and post harvest factors influencing the eating quality of selected Nectarine (Prunus persica (L.) Batsch ) cultivars. (Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/2718

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Laubscher, Nicolaas Johannes. “Pre- and post harvest factors influencing the eating quality of selected Nectarine (Prunus persica (L.) Batsch ) cultivars.” 2006. Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/2718.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Laubscher, Nicolaas Johannes. “Pre- and post harvest factors influencing the eating quality of selected Nectarine (Prunus persica (L.) Batsch ) cultivars.” 2006. Web. 15 Dec 2019.

Vancouver:

Laubscher NJ. Pre- and post harvest factors influencing the eating quality of selected Nectarine (Prunus persica (L.) Batsch ) cultivars. [Internet] [Thesis]. Stellenbosch University; 2006. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/2718.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Laubscher NJ. Pre- and post harvest factors influencing the eating quality of selected Nectarine (Prunus persica (L.) Batsch ) cultivars. [Thesis]. Stellenbosch University; 2006. Available from: http://hdl.handle.net/10019.1/2718

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Stellenbosch University

6. Valentyn, Aatika. Orthodox and alternative strategies to control postharvest decay in table grapes.

Degree: Horticulture, 2007, Stellenbosch University

URL: http://hdl.handle.net/10019.1/1802

►

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… (more)

Subjects/Keywords: Agriculture; Table grapes – Postharvest diseases and injuries; Table grapes – Postharvest losses – Prevention

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APA (6^th Edition):

Valentyn, A. (2007). Orthodox and alternative strategies to control postharvest decay in table grapes. (Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/1802

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Valentyn, Aatika. “Orthodox and alternative strategies to control postharvest decay in table grapes.” 2007. Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/1802.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Valentyn, Aatika. “Orthodox and alternative strategies to control postharvest decay in table grapes.” 2007. Web. 15 Dec 2019.

Vancouver:

Valentyn A. Orthodox and alternative strategies to control postharvest decay in table grapes. [Internet] [Thesis]. Stellenbosch University; 2007. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/1802.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Valentyn A. Orthodox and alternative strategies to control postharvest decay in table grapes. [Thesis]. Stellenbosch University; 2007. Available from: http://hdl.handle.net/10019.1/1802

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Stellenbosch University

7. Burger, G. E. (Gerrit Erasmus). Factors affecting shrivelling and friction discolouration of pears (Pyrus communis L. ).

Degree: MScAgric, Horticulture, 2005, Stellenbosch University

URL: http://hdl.handle.net/10019.1/16264

► ENGLISH ABSTRACT: Shrivelling and friction discolouration (FD), as postharvest disorders, negatively influence the marketability and potential shelf life of pears. By investigating the contributing factors… (more)

▼ ENGLISH ABSTRACT: Shrivelling and friction discolouration (FD), as postharvest disorders, negatively influence the marketability and potential shelf life of pears. By investigating the contributing factors in each of the disorders, the potential involvement of handling and storage variables were determined. This allowed for a better understanding of the responsible factors that create susceptible environments for these disorders to occur. From the moment that pears are harvested they lose weight by means of transpiration and, to a lesser extent, respiration. When excessive losses are experienced, the fruit will appear shrivelled and the marketability and shelf life are negatively influenced. By minimizing the rates of weight loss, the occurrence of shrivelling among pears during the postharvest handling can be lessened. The periods that proved to be most conducive to shrivelling (during a simulated postharvest handling duration) were where temperatures above 0 °C were experienced. These short periods proved more perilous for shrivelling than lengthy storage durations at low temperatures. This influenced the transpiration rate in such a way that the driving force accelerated the rate of weight loss in all the cultivars that were studied. Removing field heat from fresh produce and maintaining the cold chain reduces the driving force behind the transpiration of the pears. In all the cultivars studied, ‘Packham’s Triumph’, ‘Beurrè Bosc’ and ‘Forelle’, smaller and less mature fruit were more inclined to appear shrivelled. The surface area to volume ratio is fundamental in determining the rate of weight loss. This was most evident in ‘Beurrè Bosc’. Although no reproducible results could be obtained from the morphological studies, literature has attributed this phenomenon to the composition and quantity of the cuticle layer. Reduction of weight loss was obtained by sealing of the fruit stem. This obstructed water movement from the fruit through the xylem conducting tissue to the surrounding atmosphere. Not only did the stem appear greener and fresher, but less weight loss and subsequent shrivel was noticeable in the treated fruit. This effect was most evident in ‘Packham’s Triumph’ and ‘Beurrè Bosc’, but not in ‘Forelle’. ‘Forelle’ typically has a very short, thin stem in comparison to the other two cultivars.All the cultivars showed visual shrivel symptoms after 11 days at 18 °C. Rate of weight loss was the lowest in ‘Packham’s Triumph’, but due to its prominent dimensions, it appeared shrivelled before any of the other cultivars. ‘Beurrè Bosc’ lost weight at the highest rate (0.42%.day-1). As fruit injury, in the presence of oxygen, is inevitable, the oxidative enzymatic browning of pears will always be troublesome. This defensive mechanism partially prevents the infection of the fruit where epidermal cells are injured. To minimize FD, impact and frictional forces need to be lower during both harvesting and handling practices. A laboratory scale method was developed through which… Advisors/Committee Members: Huysamer, M., Jacobs, G., University of Stellenbosch. Faculty of Agrisciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture; Dissertations – Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Burger, G. E. (. E. (2005). Factors affecting shrivelling and friction discolouration of pears (Pyrus communis L. ). (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/16264

Chicago Manual of Style (16^th Edition):

Burger, G E (Gerrit Erasmus). “Factors affecting shrivelling and friction discolouration of pears (Pyrus communis L. ).” 2005. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/16264.

MLA Handbook (7^th Edition):

Burger, G E (Gerrit Erasmus). “Factors affecting shrivelling and friction discolouration of pears (Pyrus communis L. ).” 2005. Web. 15 Dec 2019.

Vancouver:

Burger GE(E. Factors affecting shrivelling and friction discolouration of pears (Pyrus communis L. ). [Internet] [Masters thesis]. Stellenbosch University; 2005. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/16264.

Council of Science Editors:

Burger GE(E. Factors affecting shrivelling and friction discolouration of pears (Pyrus communis L. ). [Masters Thesis]. Stellenbosch University; 2005. Available from: http://hdl.handle.net/10019.1/16264

Stellenbosch University

8. Van Wyk, Angelique A. (Angelique Ann). Time-temperature interaction on postharvest rind colour development of Citrus.

Degree: MScAgric, Horticulture, 2004, Stellenbosch University

URL: http://hdl.handle.net/10019.1/16456

► ENGLISH ABSTRACT: Rind colour is one of the most important external quality characteristics of citrus fruit and plays an important role in purchasing decisions by… (more)

▼ ENGLISH ABSTRACT: Rind colour is one of the most important external quality characteristics of citrus fruit and plays an important role in purchasing decisions by consumers. Consumers perceive brightlycoloured fruit to be sweet and mature, whereas citrus with a green rind is perceived to be sour and immature. However, there is a poor correlation between rind colour and internal quality, contradicting what is generally assumed by the fruit-buying public. In general, a bright orange rind colour improves consumer acceptance. Thus, it is important to ensure that the rind of citrus fruit is well-coloured on arrival at the market. Various pre-harvest cultural practices and postharvest techniques can be applied to improve rind colour. Degreening with ethylene gas is the most commonly used postharvest technology to improve rind colour, but has various negative side-effects. Degreened fruit are more prone to decay, have rinds which appear dull and flaccid, have been reported to develop off-flavours and have a shorter shelf-life period. Therefore, it is necessary to find alternatives to ethylene degreening and to extend shelf-life of citrus fruit. Under normal orchard conditions, rind colour development is associated with low night temperatures, usually experienced during autumn or following the passing of a cold front. To simulate cold front conditions, a hydrocooler and cold room were used to rapidly drop fruit temperature to 4 ºC for 6 hours, and then fruit were incubated at 20 to 22 ºC for 72 hours. This “cold shock” treatment of ‘Nules Clementine’ mandarin improved rind colour to a level similar to that of degreened fruit in the 2002 season due to a decrease in chlorophyll content and increase in carotenoid content. However, this result could not be repeated. Storage temperature is one of the most important postharvest factors affecting rind colour. Citrus fruit shipped to export markets requiring low temperatures (-0.6 ºC) for pest disinfestations purposes have been reported to arrive with poor rind colour. Shipping under low temperatures results in poor rind colour of fruit on arrival in the market. To comply with the USA’s phytosanitary requirement for imported citrus, fruit is held at -0.6 ºC for a minimum of 22 days. The effect of shipping at various temperatures (-0.6 ºC or 4.5 ºC), durations and the influence of initial rind colour, “orange” or “yellow”, on fruit colour upon arrival in the market was evaluated. Fruit shipped at a higher temperature (4.5 ºC) had a marginally better rind colour than fruit shipped at -0.6 ºC. The perceived loss of rind colour following shipping at sub-zero temperatures is probably due to carotenoid degradation. Therefore, initial rind colour plays a critical role in final product quality. Depending on market destination and shipping temperature, pale-coloured fruit should not be packed for markets sensitive to rind colour. Holding temperature after shipping can be effectively used to improve the rind colour of fruit arriving in the market with… Advisors/Committee Members: Barry, G.H., Huysamer, M., University of Stellenbosch. Faculty of Agrisciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture; Dissertations – Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Van Wyk, A. A. (. A. (2004). Time-temperature interaction on postharvest rind colour development of Citrus. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/16456

Chicago Manual of Style (16^th Edition):

Van Wyk, Angelique A (Angelique Ann). “Time-temperature interaction on postharvest rind colour development of Citrus.” 2004. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/16456.

MLA Handbook (7^th Edition):

Van Wyk, Angelique A (Angelique Ann). “Time-temperature interaction on postharvest rind colour development of Citrus.” 2004. Web. 15 Dec 2019.

Vancouver:

Van Wyk AA(A. Time-temperature interaction on postharvest rind colour development of Citrus. [Internet] [Masters thesis]. Stellenbosch University; 2004. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/16456.

Council of Science Editors:

Van Wyk AA(A. Time-temperature interaction on postharvest rind colour development of Citrus. [Masters Thesis]. Stellenbosch University; 2004. Available from: http://hdl.handle.net/10019.1/16456

Stellenbosch University

9. Reynolds, Johan Schalk. Colour improvement of bi-coloured pears.

Degree: MScAgric, Horticulture, 2001, Stellenbosch University

URL: http://hdl.handle.net/10019.1/52166

► ENGLISH ABSTRACT: Poor colour development in bi-coloured pears is a big concern for the South African deciduous fruit industry, resulting in low Class 1 packouts… (more)

▼ ENGLISH ABSTRACT: Poor colour development in bi-coloured pears is a big concern for the South African deciduous fruit industry, resulting in low Class 1 packouts with huge financial implications. The objective of this study was, therefore, to evaluate manipulation practices to improve colour development. The effect of summer pruning on the colour development of 'Rosemarie' pear fruit was studied over two seasons. Pruning consisted of removing the upright shoots of the current season's growth on the lateral branches. The effect of the time of summer pruning on Class 1 packout percentage and average fruit mass were determined. The percentage blushed fruit (colour grading 1-10) of the trees pruned in November or pruned repeatedly from November to just before harvest were significantly higher than for unpruned control trees or trees pruned at other times. Fruit mass was not affected by summer pruning. A second study was conducted on 'Rosemarie' and 'Forelle' pears and the treatments consisted of non-pinched and pinched, where the bourse shoots were cut back at petal drop. There were no significant differences in fruit colour, fruit size, flesh firmness and total soluble solids after pinching compared to the control. In a third study on 'Rosemarie' and 'Forelle' trees, bourse shoots were removed in combination with defoliation. Spur leaves were removed at different times throughout the season from petal drop towards harvest. Both bourse shoots (Rosemarie), or one bourse shoot (Forelle) per cluster was removed as control, one treatment where no bourse shoots were removed served as a secondary control. Spur leaf removal on 'Rosemarie' and 'Forelle' did not have any significant effect on fruit set, fruit size or total soluble solids. In 'Rosemarie', there was also no significant effect on fruit colour. In 'Forelle', colour improved significantly between unmanipulated branches (control 1) and branches were one bourse shoot was removed (control 2). However, all treatments compared to control 1, improved red colour, indicated by a significant decrease in the hue angle values and an increase in Class 1 packout. A fourth study was conducted on 'Flamingo', 'Forelle' and 'Rosemarie' pears. A number of urea applications were made onto the fruit. Fruit nitrogen content increased with urea sprays. Urea sprays did not affect red colour of 'Flamingo', 'Forelle' and 'Rosemarie' pears. Urea sprays had no effect on the anthocyanin concentration (ug.g") of 'Rosemarie' and 'Flamingo'. However, there was a quadratic relationship between number of urea sprays and anthocyanin concentration of 'Forelle'. There were not significant differences in the chlorophyll a and b concentrations of 'Flamingo' and 'Forelle'. Urea applications significantly increased the chlorophyll a concentration of 'Rosemarie'. In contrast there was no significant difference in the chlorophyll b concentration of 'Rosemarie'. The carotenoid concentration of 'Flamingo' and 'Forelle' was not affected by urea applications. In contrast the… Advisors/Committee Members: Theron, K. I., Jacobs, G., Huysamer, M., Stellenbosch University. Faculty of AgriSciences. Dept. of Horticulture..

Subjects/Keywords: Pear – Color

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Reynolds, J. S. (2001). Colour improvement of bi-coloured pears. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/52166

Chicago Manual of Style (16^th Edition):

Reynolds, Johan Schalk. “Colour improvement of bi-coloured pears.” 2001. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/52166.

MLA Handbook (7^th Edition):

Reynolds, Johan Schalk. “Colour improvement of bi-coloured pears.” 2001. Web. 15 Dec 2019.

Vancouver:

Reynolds JS. Colour improvement of bi-coloured pears. [Internet] [Masters thesis]. Stellenbosch University; 2001. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/52166.

Council of Science Editors:

Reynolds JS. Colour improvement of bi-coloured pears. [Masters Thesis]. Stellenbosch University; 2001. Available from: http://hdl.handle.net/10019.1/52166

Stellenbosch University

10. Mare, Leon. Various storage techniques of plums and avocados.

Degree: MSc, Horticulture, 2002, Stellenbosch University

URL: http://hdl.handle.net/10019.1/53212

► ENGLISH ABSTRACT: Historically the storage of South African plum fruit involved cold storage at single low temperatures (-O.5°C). The ever present problem of internal breakdown,… (more)

▼ ENGLISH ABSTRACT: Historically the storage of South African plum fruit involved cold storage at single low temperatures (-O.5°C). The ever present problem of internal breakdown, however, led to the development of the dual temperature storage regime (a type of intermittent warming) which was found to restrict the level of internal breakdown. However, this temperature regime led to the development of or unmasking of gel breakdown (GB). During season one it was proposed that 'Songold' and 'Angeleno' plums could be stored at a single high temperature (7.5°C) during the shipping period (18 days) in combination with controlled atmospheres (CA). This was compared to the commercially used dual temperature regime (10 days at -O.5°C and eight days at 7.5°C). During season two the temperature regimes were adjusted to mirror the storage of the fruit from the date of harvest until the fruit is purchased. During the shipping period the dual temperature regime and the single high temperature regime were still compared. It was hypothesised that the fruit could be stored at the higher temperature in combination with CA during shipping, and this would allow the ripening of the fruit to be retarded, retaining good quality without exposure to the low, chilling inducing temperatures associated with the dual temperature regime. The storage of both plum cultivars at the single high temperature in combination with CA had a positive influence on delaying the ripening of the fruit. Most noticeable was the delay of fruit softening and the restriction of colour and GB development of the 'Songold' plums. Most importantly, these results were achieved without the fruit being exposed to the low, injurious temperatures associated with the dual temperature regime. It was, however, concluded that due to the suppressed climacteric trait of these plums more benefit could be gained from the higher temperature storage in combination with CA on climacteric plums which display stronger ripening patterns. In contrast to the plum industry, the use of CA in the storage of avocado fruit has risen to about 95% of the exported fruit. CA storage of avocados has shown positive results in retaining fruit firmness, restricting disorder development and extending the shelf life. Recently, research with l-methylcyclopropene (l-MCP) storage of avocados has been found to be as successful as CA storage and there is a belief that it will be the answer to storage for the avocado industry once registered for commercial use. During the first experiment, 'Fuerte' and 'Hass' avocados were treated with CO2 shocks (C02 levels which greatly exceed the initial intercellular concentrations of CO2 are known as CO2 shock treatments). These shock treatments were done over a series of three time periods and four CO2 concentrations for the 'Fuerte' avocados and two time periods and two concentrations for the 'Hass' avocados. Results were disappointing, as the fruit treated with CO2 were not able to retain their quality. For the second experiment,… Advisors/Committee Members: Huysamer, M., Holcroft, D. M., Dodd, M. C., Stellenbosch University. Faculty of AgriSciences. Dept. of Horticulture..

Subjects/Keywords: Plum – Storage; Avocado – Storage

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mare, L. (2002). Various storage techniques of plums and avocados. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/53212

Chicago Manual of Style (16^th Edition):

Mare, Leon. “Various storage techniques of plums and avocados.” 2002. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/53212.

MLA Handbook (7^th Edition):

Mare, Leon. “Various storage techniques of plums and avocados.” 2002. Web. 15 Dec 2019.

Vancouver:

Mare L. Various storage techniques of plums and avocados. [Internet] [Masters thesis]. Stellenbosch University; 2002. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/53212.

Council of Science Editors:

Mare L. Various storage techniques of plums and avocados. [Masters Thesis]. Stellenbosch University; 2002. Available from: http://hdl.handle.net/10019.1/53212

Stellenbosch University

11. Du Plessis, S. F. (Stephanus Francois). Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.).

Degree: MScAgric, Horticultural Science, 2003, Stellenbosch University

URL: http://hdl.handle.net/10019.1/53404

► 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… (more)

▼ 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… Advisors/Committee Members: Huysamer, M., Jacobs, G., Stellenbosch University. Faculty of AgriSciences. Dept. of Horticultural Science..

Subjects/Keywords: Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Du Plessis, S. F. (. F. (2003). Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.). (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/53404

Chicago Manual of Style (16^th Edition):

Du Plessis, S F (Stephanus Francois). “Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.).” 2003. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/53404.

MLA Handbook (7^th Edition):

Du Plessis, S F (Stephanus Francois). “Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.).” 2003. Web. 15 Dec 2019.

Vancouver:

Du Plessis SF(F. Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.). [Internet] [Masters thesis]. Stellenbosch University; 2003. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/53404.

Council of Science Editors:

Du Plessis SF(F. Effects of packaging and postharvest cooling on quality of table grapes (Vitis vinifera L.). [Masters Thesis]. Stellenbosch University; 2003. Available from: http://hdl.handle.net/10019.1/53404

Stellenbosch University

12. Burger, D. A. (Dirk Albert). Postharvest berry split and abscission in 'Thompson Seedless' and 'Waltham Cross' table grapes.

Degree: MScAgric, Horticulture, 2000, Stellenbosch University

URL: http://hdl.handle.net/10019.1/51877

► 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… (more)

▼ 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.… Advisors/Committee Members: Taylor, M. A., Jacobs, G., Huysamer, M., Stellenbosch University. Faculty of AgriSciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Burger, D. A. (. A. (2000). Postharvest berry split and abscission in 'Thompson Seedless' and 'Waltham Cross' table grapes. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/51877

Chicago Manual of Style (16^th Edition):

Burger, D A (Dirk Albert). “Postharvest berry split and abscission in 'Thompson Seedless' and 'Waltham Cross' table grapes.” 2000. Masters Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/51877.

MLA Handbook (7^th Edition):

Burger, D A (Dirk Albert). “Postharvest berry split and abscission in 'Thompson Seedless' and 'Waltham Cross' table grapes.” 2000. Web. 15 Dec 2019.

Vancouver:

Burger DA(A. Postharvest berry split and abscission in 'Thompson Seedless' and 'Waltham Cross' table grapes. [Internet] [Masters thesis]. Stellenbosch University; 2000. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/51877.

Council of Science Editors:

Burger DA(A. Postharvest berry split and abscission in 'Thompson Seedless' and 'Waltham Cross' table grapes. [Masters Thesis]. Stellenbosch University; 2000. Available from: http://hdl.handle.net/10019.1/51877

Stellenbosch University

13. Fraser, W. J. Manipulation of the taste of Regal Seedless (Vitis vinifera L.) table grapes.

Degree: Viticulture and Oenology, 2007, Stellenbosch University

URL: http://hdl.handle.net/10019.1/3079

►

Thesis (MscAgric (Viticulture and Oenology)) – University of Stellenbosch, 2007.

Regal Seedless is a white, seedless grape which has the potential to become a profitable cultivar… (more)

Subjects/Keywords: Viticulture and oenology; Table grapes – Biotechnology; Fruit – Flavor and odor

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APA (6^th Edition):

Fraser, W. J. (2007). Manipulation of the taste of Regal Seedless (Vitis vinifera L.) table grapes. (Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/3079

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fraser, W J. “Manipulation of the taste of Regal Seedless (Vitis vinifera L.) table grapes.” 2007. Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/3079.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fraser, W J. “Manipulation of the taste of Regal Seedless (Vitis vinifera L.) table grapes.” 2007. Web. 15 Dec 2019.

Vancouver:

Fraser WJ. Manipulation of the taste of Regal Seedless (Vitis vinifera L.) table grapes. [Internet] [Thesis]. Stellenbosch University; 2007. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/3079.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fraser WJ. Manipulation of the taste of Regal Seedless (Vitis vinifera L.) table grapes. [Thesis]. Stellenbosch University; 2007. Available from: http://hdl.handle.net/10019.1/3079

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Stellenbosch University

14. Khumalo, Ngcebo Parton. Factors affecting post-storage quality of ‘Nules Clementine’ mandarin fruit with special reference to rind breakdown.

Degree: Horticulture, 2006, Stellenbosch University

URL: http://hdl.handle.net/10019.1/1944

►

Thesis (MSc (Horticulture)) – University of Stellenbosch, 2006.

Rind breakdown of ‘Nules Clementine’ mandarin (Citrus reticulata Blanco) is a physiological rind disorder that develops during storage.… (more)

▼

Thesis (MSc (Horticulture)) – University of Stellenbosch, 2006.

Rind breakdown of ‘Nules Clementine’ mandarin (Citrus reticulata Blanco) is a physiological rind disorder that develops during storage. The disorder appears following leakage of essential oil from oil glands in the flavedo, which then leaks into and oxidises the albedo. Oxidised tissue appears as brown spots in the rind. Occurrence of this disorder over the years has caused high financial losses to ‘Clementine’ mandarin producers and exporting companies. Therefore, research aimed at solving this problem was identified as a priority by the citrus industry. Several factors have been reported to be associated with rind breakdown of ‘Clementine’ mandarin fruit, and include environmental factors, fruit maturity at harvest, ethylene gas degreening, storage temperature and storage duration, canopy position where fruit are borne, plant growth regulators, and differences in susceptibility among selections. Practical information has been generated on rind breakdown, but the basic physiology of the disorder is still unresolved. The objective of this study was, therefore, to quantify the effects of various factors on the development of rind breakdown of ‘Nules Clementine’ mandarin fruit, as well as to establish an association between rind pigments and rind antioxidant capacity on the development of this disorder. In this study a series of five experiments was conducted, and included quantifying the differences in susceptibility to rind breakdown between ‘Nules’ and ‘Oroval Clementine’ mandarin fruit, investigating the effects of fruit canopy position, harvest date, ethylene gas degreening, storage temperature and duration on the development of rind breakdown. The effect of these factors on rind pigments and antioxidant capacity was also reported. Generally, ‘Nules’ and ‘Oroval Clementine’ mandarin fruit exhibited similar characteristics at harvest, in terms of maturity and antioxidant capacity. After storage, ‘Nules Clementine’ mandarin developed higher levels of rind breakdown than ‘Oroval Clementine’ mandarin. However, the difference in susceptibility to rind breakdown of ‘Nules’ and ‘Oroval Clementine’ mandarin fruit could not be associated with the antioxidant capacity measured at harvest...

Advisors/Committee Members: Barry, G. H., Huysamer, M., De Kock, A. V., University of Stellenbosch. Faculty of Agrisciences. Dept. of Horticulture..

Subjects/Keywords: Horticulture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Khumalo, N. P. (2006). Factors affecting post-storage quality of ‘Nules Clementine’ mandarin fruit with special reference to rind breakdown. (Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/1944

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Khumalo, Ngcebo Parton. “Factors affecting post-storage quality of ‘Nules Clementine’ mandarin fruit with special reference to rind breakdown.” 2006. Thesis, Stellenbosch University. Accessed December 15, 2019. http://hdl.handle.net/10019.1/1944.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Khumalo, Ngcebo Parton. “Factors affecting post-storage quality of ‘Nules Clementine’ mandarin fruit with special reference to rind breakdown.” 2006. Web. 15 Dec 2019.

Vancouver:

Khumalo NP. Factors affecting post-storage quality of ‘Nules Clementine’ mandarin fruit with special reference to rind breakdown. [Internet] [Thesis]. Stellenbosch University; 2006. [cited 2019 Dec 15]. Available from: http://hdl.handle.net/10019.1/1944.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Khumalo NP. Factors affecting post-storage quality of ‘Nules Clementine’ mandarin fruit with special reference to rind breakdown. [Thesis]. Stellenbosch University; 2006. Available from: http://hdl.handle.net/10019.1/1944

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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Open Access Theses and Dissertations