Development of a technique to sample and quantify pineapple internal atmosphere

Abstract

Introduction. As a living organism, fruit is a site of intense gas exchange due to respiration. Carbon dioxide, oxygen and ethylene are the main components involved in this biological activity; they influence the fruit maturity and ripening phenomena. To help studies on pineapple ripening, this paper presents an easy technique to recover and measure the internal atmosphere of pineapple. Materials methods. Experiments were performed with 30 pineapples (two varieties) at the maturity stage. After a procedure validation with standard gas, the sampling technique was applied to pineapple pieces. The fruit’s internal atmosphere was released after scratching the fruit into a calcium chloride-saturated brine. The recovered gas was transferred into an air-tight flask equipped with a septum and a bladder. The headspace was analysed with a gas chromatograph or an IR analyser, at atmospheric pressure. Results. Twenty complete procedure cycles were done with three different standard gases to test the reproducibility of the technique. Each pineapple of each variety was sampled once according to the procedure. All of the results were situated in the best standardisation range for reproducibility. Conclusion. The main advantages and drawbacks of the technique are presented.