Abstract
ABSTRACTSuper-atmospheric O2 has been shown to affect respiration rate (RR), but no model describing its effect on RR for pomegranate arils has been reported. This study investigated the effects of four different gas compositions (5 kPa O2, 10 kPa CO2 and 85 kPa N2; 10 kPa O2, 5 kPa CO2 and 85 kPa N2; 70 kPa O2, 10 kPa CO2 and 20 kPa N2; and air) on RR of pomegranate arils (cv. Wonderful) stored at 5°C. Michaelis–Menten enzyme kinetics models were used to investigate the effect of CO2 inhibition on O2 consumption rate. Respiratory quotient was used to determine fermentation threshold. The O2 consumption rate increased from 0.87 to 2.81 mL/kg h, with increase in O2 concentration from 5 kPa to 70 kPa. All enzyme kinetics model parameters adequately described the influence of gas concentration on aril RR with correlation coefficient (R2adj = 81–91%).
Highlights
After harvest, fresh produce are susceptible to increased physiological stress and deterioration in quality due to accelerated respiration rate (RR) (Aindongo, Caleb, Mahajan, Manley, & Opara, 2014; Caleb, Mahajan, Opara, & Witthuhn, 2012a)
O2 concentration decreased from 21 kPa to 14.06 kPa for air storage and from 70.05 kPa of O2 decreased to 37.83 kPa under super-atmospheric O2
The headspace CO2 concentration increased in all modified atmosphere (MA) storage from the first day of storage and it reached the recommended range of 20 kPa on day 6
Summary
Fresh produce are susceptible to increased physiological stress and deterioration in quality due to accelerated respiration rate (RR) (Aindongo, Caleb, Mahajan, Manley, & Opara, 2014; Caleb, Mahajan, Opara, & Witthuhn, 2012a). This process consumes O2 and produces CO2 in a series of enzymatic reaction (Iqbal, Rodrigues, Mahajan, & Kerry, 2009). Banda, Caleb, Jacobs, and Opara (2015) studied the effect of O2 (5, 21 and 30 kPa) and CO2 (0, 10 and 40 kPa) on the RR of ‘Wonderful’ pomegranate arils These studies showed that low O2 atmosphere significantly reduced the RR. Recent studies have introduced the benefits of super-atmospheric O2 (>70 kPa) to overcome the limitation of low O2 atmosphere on postharvest physiology and quality maintenance of fresh produce (Belay, Caleb, & Opara, 2017; Maghoumi et al, 2013; Molinu et al, 2016)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
