Heating of canned fruits and vegetables: Deaeration and texture changes

The effect of deaeration of apple and/or carrot during heating at 60 °C–100 °C for 20–60 min in packages with hermetic and non-hermetic closures on the texture changes of processed tissues was studied. In heated plant tissues the residual gas content was determined. The texture was evaluated using Instron apparatus, (model 5544, Instron Ltd. UK) by pressing of cylindrical samples of apple and/or carrot between two flat plates. The maximum stress and the modulus of elasticity for each sample were determined.After all heat treatments the total content of free gas in fresh plant tissues decreased more in samples heated in non-hermetic packaging. The correlation between the amount of expelled gas and the texture loss of processed carrot and/or apple was found, the samples heated in the hermetic packaging provided lower texture deterioration.