The residual ozone concentration after passaging through the
container with 4.0 kg of pears was determined by the iodometric
method [23] which consists in bubbling ozone into 50 mL solution of
potassium iodide (KI) 1 N, and Iodine (I2) being produced. To ensure
that the reaction shifts towards producing I2, the medium had to be
acidified with 2.5 mL sulphuric acid (H2SO4) 1 N. The solution was
then titrated with sodium thiosulphate (Na2S2O3) 0.005 N, and a 1%
starch solution was used as an indicator.