CA FACILITY CELEBRATES FIRST BIRTHDAY

The state-of-the-art controlled atmosphere (CA) facility at Stellenbosch University’s Horticultural Sciences’ celebrated its first birthday this year. The CA facility was made possible through an industry donation by Hortgro Pome who made the investment of R2.5m last year and aims to help solve post-harvest problems within the deciduous fruit industry. Post-harvest research is critical to the future success of new apple cultivars.

On 5 November 2019, approximately 80 people attended the CA Storage Research Feedback held by the Hortgro Science CA Storage Group at the Department of Horticultural Sciences. This meeting is held annually in November but had record attendance this year.

Since the industry has identified CA-storage as a research gap, it has stimulated funding, research and collaboration between all research organisations on this topic, bringing new ideas to the party and giving this research theme momentum. This also provides the industry with much needed post-graduate specialists in this field. Two students, Monja Gerber (PhD) and Braam Mouton (MSc), presented their research projects on ‘Granny Smith’ apple long-term storage techniques under the supervision of Dr Elke Crouch and collaboration with Dr Pandian Thirupathi (post-doctoral fellow). Monja Gerber’s project is also funded by the Post Harvest Innovation Fund proving the importance of this type of research. This study is done in collaboration with the ARC (Anél Botes) and Experico (Daniël Viljoen). Braam Mouton’s study looks at differences in quality after storing fruit for 9 months under low oxygen storage techniques that adjust the atmosphere according to the fruit condition. Other topics covered were ‘Cripps’ Pink’ browning factors during long term CA storage presented by Heleen Bergman (Experico) in collaboration with Dr Elke Crouch and an honours student, Tsepo Kholoane, at SU. Long term storage techniques of pears were covered by Anél Botes from the ARC. An international guest from Bolzano, Italy, Hubert Wieser also presented on new Isolcel CA technologies that allow for more accurate measurements of DCA-RQ (Storefresh), new intelligent CO₂ scrubbing systems that reduce the use of electricity consumption by 50% (ECO line) and digital starch breakdown measurement (Amilon). Vega Brink from Gas at Site gave an update on dynamic controlled atmosphere adoption in the USA.

This day proved that the foresight of Richard Hurndall (CA group chairman) at Hortgro driving the revival of the CA theme is working. Hurndall quoted the first CA group chairman John Findlay who liked to say: “We are here to learn from our mistakes”.

The current new challenge for CA research is space. The equipment installed at the Dept. of Horticultural Sciences has the capacity to run larger units but currently, there is no more space available to add to the current airtight containers for the great requirement for long term storage trials. This requirement is due to the fact that higher prices are earned by supplying fruit in the offseason. However, storing at a high cost also carries massive risks and the research is therefore required to know exactly how to reduce that risk. Prof Wiehann Steyn at Hortgro has taken over the reins from Richard Hurndall and will be driving the CA research theme and funding to further address these future challenges.

Photo (from left to right): Prof. Wiehann Steyn (Hortgro), Dr Pandian Thirupathi (SU), Mr. Gustav Lötze (SU), Ms. Monja Gerber (SU), Ms. Anel Botes (ARC), Ms. Heleen Tayler (Experico), Dr Elke Crouch (SU), Mr. Richard Hurndall (Hortgro, CA group Chairman).