Vacuum infiltration with calcium chloride influences oxygen distribution in apple fruit flesh

Abstract

Oxygen distribution within flesh tissues of ‘Cox's Orange Pippin’ and ‘Braeburn’ apples was determined following vacuum infiltration with solution. Vacuum infiltration with 0.2 M calcium chloride (CaCl2) solution and, to a lesser extent, with water increased estimates of skin resistance to O2 diffusion and resulted in reduced O2 levels in tissues beneath the skin and in the central core cavity. Gradients in O2 concentration across skin and flesh tissues were increased by vacuum infiltration but the proportional increase in O2 gradient across the flesh tissues was higher than the gradient across the skin. These effects were due to decreased O2 diffusivity in flesh tissues and increased skin resistance to gas diffusion. Vacuum infiltration effects on O2 concentration gradients declined with time. Development of controlled or modified atmosphere (CA/MA) storage techniques for vacuum infiltrated fruit should take account of the altered O2 distribution characteristics within flesh tissues to avoid detrimental effects on internal quality.