Juice was extracted from McIntosh apples that had been
stored commercially under controlled atmosphere. The apples
were crushed and pressed in a crusher-press model no. EG 260-
X6 (Goodnature Products Inc., New York, USA) under
maximum pressure of 1500 psi. About 20 L of juice was
obtained from 30 kg of apples. For each experiment, 4 L of juice
was used. The remaining juice was stored at temperature close
to 0 °C prior to use.