Membrane lipid composition and tissue leakage of pre- and early-climacteric banana fruit

Banana fruit (Musa, AAA) harvested when green and unripe were held in ethylene-free air at 20 °C. Carbon dioxide evolution and the soluble solids content of pulp increased slowly during the preclimacteric, whereas leakage of amino nitrogen and electrolytes from pulp slices did not change. Soluble solids, leakage, and ethylene evolution increased rapidly during the climacteric. The total phospholipid content of pulp did not change before or during the climacteric. The amount of linolenic acid esterified to pulp phospholipid increased slowly in preclimacteric fruit and rapidly during the climacteric. Linoleic acid in pulp phospholipid decreased during the preclimacteric and climacteric periods. The ratio of linolenic to linoleic esters increased from 0.25 to 0.39, but the sum of linolenic and linoleic did not change before or during the climacteric. The change in phospholipid fatty acid esters probably increases membrane fluidity, and may affect metabolism of the fruit.