Quality Management

Quality Management

Quality management refers to maintaining quality throughout the logistical chain to the end consumer. With reference to stone fruit, shrivel due to moisture loss is the main post-harvest defect and therefore the key research focus area. Dr Elmi Lötze and PhD student Dr Imke Kritzinger investigated peel properties affecting cultivar and fruit susceptibility to shrivel. They found that moisture loss, although a key driver of shrivel, doesn’t necessarily determine whether shrivel develops or not. The peel properties and components of some cultivars decrease their susceptibility to shrivel despite considerable moisture loss. This information can potentially be used in the selection of new cultivars and may also in future allow us to predict the shrivel risk in particular seasons.

Expertise:
Quality management workgroup

Projects list

POME FRUIT PROJECTS
  • Assessment of malic acid equivalents of Forelle pears on the storability and taste thereof. (D Viljoen)
  • Thermal and non-thermal treatments of stone and pome fruit: Towards efficient phytosanitary measures. (O Caleb, Z Belay  and N Nyamende)  - see Pre- and post-har-vest pathology [Abstract]
  • The effect of a water deficit on fruit tree phenology, fruit production, fruit quality and storability of Fuji and Cripps’ Pink apples. (S Midgley and S Daiber) - see Irrigation and nutrition [Abstract]
  • Moisture loss studies in pears. (A Botes, E Crouch and A Same) [Abstract]
  • Revision of FEMA release standards when fruit do not make FEMA firmness or sugar criteria. (D Viljoen) [Abstract]
  • To develop marketing protocols for FEMA designated orchards that are harvested two to three weeks after normal release but do not qualify for FEMA release. (D Viljoen) [Abstract]
  • Integrated post-harvest ethylene man-agement along the value chain: From the farm to the consumer. (O Caleb, Z Belay and M Nkohla) [Abstract]
  • The use of HarvistaTM (pre-harvest 1-MCP) application to prevent green colour loss and reduce blush of Granny Smith apples. (D Viljoen) [Abstract]
  • Fuji browning types explored via X-Ray CT in collaboration with existing trial. (E Crouch & K Chigwaya)  [Abstract]
  • To investigate different step down cool-ing regimes, utilised in conjunction with SmartFreshSM, to reduce the risk of internal browning of Cripps’ Pink apples and provide year round supply of good quality fruit. (H Tayler, D Viljoen, E Crouch and T Kholoane) – see Storage techniques [Abstract]
  • Quantifying the effect of bag perforations on forced-air cooling cycles and post storage quality of apples. (D Viljoen) [Abstract]
  • The effect of DPA on fruit quality in pome fruit. (A Botes) [Abstract]
  • The use of HarvistaTM (pre-harvest 1-MCP) application to control superficial scald on Packham’s Triumph pears. (D Viljoen) [Abstract]
STONE FRUITS PROJECTS
  • Technology testing for the ability to control shrivel in cold-stored plums and nectarines. (H Viljoen)
  • Thermal and non-thermal treatments of stone and pome fruit: Towards efficient phy-tosanitary measures. (O Caleb, Z Belay and N Nyamende)  - see Pre- and post-harvest pathology [Abstract]
  • Effect of irradiation as a mitigation treat-ment on storage quality of early peaches and nectarines for airfreight consignments. (H Viljoen) – see Phytosanitary and market access [Abstract]
  • Evaluation of the 8 mm penetrometer plunger to determine harvest maturity on plums. (H Viljoen) [Abstract]
  • Application of post-harvest edible coat-ings to alleviate shrivel in plums and nectar-ines. (O Fawole and S Riva) [Abstract]
  • Profiling sugar metabolism in plums as related to maturity, cultivar difference and post-harvest storage regimes. (O Fawole and T Majoni) [Abstract]
  • Application of postharvest bioactive edible coatings and natural antimicrobial peptides as a green-solution to alleviate shrivel and extend storage life of plums. (O Fawole and N Jenneker) [Abstract]
  • Develop a six week storage protocol for plums harvested from week 5 onwards. (H Viljoen) [Abstract]
  • Develop optimum ripening protocols for nectarines and plums arriving too green (skin colour) or too firm in market. (H Viljoen) [Abstract]
  • Identify and test improved packaging as well as humidity control in cold stores to reduce moisture loss and shrivel in nectarines. (H Viljoen) [Abstract]
  • Identify and test improved packaging as well as humidity control in cold stores to reduce moisture loss and shrivel in plums. (H Viljoen) [Abstract]
  • Postharvest moisture loss studies in Japanese plums (Prunus salicina Lindl). (E Lötze and I Kritzinger) [Abstract]
  • Determine the CO2 sensitivity of the four main plum cultivars. (A de Kock) [Abstract]
  • Evaluation of micro-perforated LDPE bags for reduction of postharvest moisture loss and shrivelling in Japanese plums (E Lötze)*
  • Peel water vapour permeance of Japanese plums as indicator of susceptibility to postharvest shriveling (I Kritzinger)*