Dynamic controlled atmosphere storage of New Zealand grown Hass avocados
J. Burdon, N. Lallu, G. Haynes, K. McDermott, D. billing
Program and Abstract. 2007 Australasian Postharvest Conference. Crowne Plaza Terrigal, NSW, Australia. 12 September 2007. 87 p.
2007
บทคัดย่อ
Dynamic controlled atmosphere storage of New Zealand grown Hass avocados
The outturn quality of 'Hass' avocados shipped from New Zealand under controlled atmosphere (CA) has been variable. Recommended CA for avocado is in the range 2-5% O2 and 3-10% CO2 but CA conditions for New Zealand grown 'Hass' avocados have not been optimised. There are two approaches to applying CA, static (SCA) or dynamic (DCA) systems. The O2 level in SCA is maintained at a pre-determined level throughout storage whereas in DCA the O2 level is set dependent on a low O2 stress response from the fruit. To demonstrate the impact on fruit quality of DCA compared to SCA, 'Hass' avocados were stored for 6 weeks at 5°C in DCA (<3%O2 / 0.5%CO2) or SCA (5%O2 / 5%CO2), and assessed for quality at the end of storage and when ripe. In addition, fruit were stored in DCA plus CO2 (<3%O2 / 5%CO2) to determine the impact of CO2. The quality of DCA-stored fruit was significantly better than SCA-stored fruit, with a lower incidence of rots after storage and when ripe. However, inclusion of 5% CO2 with DCA resulted in rot levels similar to SCA-stored fruit. It is concluded that the quality of DCA-stored fruit was better than SCA-stored fruit, and that a large component of the difference was the result of rot expression stimulated by CO2 in the storage atmosphere.