Effect of calcium concentration and vacuum pressure on pulp hardness and Ca quantity of post harvest ‘Golden Delicious’ apples

Abstract

In this study, fruits of the apple cv. ‘Golden Delicious’ (Malus_/domestica Borkh.) were subjected to post-harvest calcium infiltration under vacuum. Research has been performed in two harvest years. In the first year, ‘Golden Delicious’ fruit were infiltrated with 0, 2, 4 or 5% CaCl2 solutions and stored at 0 °C for up to 6 months. In the first year of harvest, apples were kept under -53.3 kPa and -66.6 kPa vacuum pressures for 2 and 2.5 minutes. In the second harvest year, ‘Golden Delicious’ apples were infiltrated with 0, 2, 4 CaCl2 solutions and stored at 0 °C for up to 6 months. In that harvest year, apples were investigated under -26.6 kPa and -53.3 kPa vacuum pressure for 2.5 min. and submerged into solution for 1 min. Calcium chloride absorbed apples were investigated for surface hardness, water soluble matter criteria and compared with untreated apples. The highest calcium infiltration was determined under -66.6 kPa vacuum pressure in 5% CaCl2 solution but also the highest harm was also seen under the same conditions. The most suitable vacuum pressure for calcium infiltration and pulp hardness was found to be -53.3 kPa. The best Ca quantity and pulp hardness was obtained in 4% CaCl2 solution so that the pulp hardness values after 6 months storage were nearly same or higher than control fruits.