Li 6262 co2 h2o analyzer

The respiration rate was determined by conducting an infrared analysis. Five replicate groups of three papaya fruits from each treatment were weighed, and then sealed in a 2.4-L container at 25°C. An infrared gas analyzer (Li-6262 CO₂/H₂O analyzer, LI-COR, America) was used to monitor CO₂ concentration in the container. A colorimeter (Minolta, model CR-400, Tokyo, Japan) was used to determine the color characteristics of the papaya pericarp. Three independent points in the equatorial region of the papaya fruit skin were chosen to determine color characteristics. The method for assessing color characteristics has been described previously (Liu et al., 2014 (link)).

According to the method of Huang et al. [13 (link)], respiration rate was measured using an infrared gas analyzer (Li-6262 CO₂/H₂O analyzer, LI-COR, Inc, USA). Before being put into a plastic container (2.4 L) at 25 °C, three replicates of nine fruits from each treatment were weighted. The amount of CO₂ was recorded for 5 min. The respiration rate was expressed as nmol kg⁻¹ s⁻¹.
Ethylene release rate was analyzed by the method of Huang et al. [13 (link)]. Three fruits were weighted and then placed into a 2.4 L plastic container. After 2 h, 10 mL of the headspace volume was sampled into a glass container, and then a sample (1 mL) was injected into the gas chromatography (GC-2010; Shimadzu, Kyoto, Japan) equipped with a 30 m HP-PLOT Q capillary column (Agilent Technologies, USA) and a flame ionization detector to measure the amount of ethylene production. Ethylene release rate was expressed as mmol kg⁻¹s⁻¹.