Methods for gas permeability measurement in edible films for fruits and vegetables: a review

Abstract

Permeability is a crucial parameter to describe the transport rate of a gas under pressure gradient, relevant to gas molecule movement in pores. The gas permeability of edible film, used on fresh or minimally processed fruits and vegetables, is an important parameter because it directly affects the product’s respiration rate and metabolic activity. The present study summarizes the principal methods for gas permeability measurement in edible films, considering methods developed at laboratory scale and the methods of the American Society for Testing and Materials Standards (ASTM), some of which have been adapted for edible films. The methods are classified as follows: gravimetric, differential pressure, and continuous flow. Gas permeability results depend heavily on the procedure achieved and laboratory conditions employed, as well as the preconditioning of the films before the tests.

Keywords:
respiration rate; permeation; film properties; postharvest