Food Science and Technology Library

The effects of coating and thawing conditions on the colour change (lightness, chroma and hue), total soluble solids (TSS), pH, ascorbic acid (AA) content, total titratable acidity (TTA) content and texture of frozen jackfruit bulbs (Artocarpus heterophyllus var. J33) by direct freezing were investigated. Individual bulb of ripe jackfruit was pre-treated with T1: without coating (Control), T2: 16°Bx sugar and T3: 2°Bx salt solution. Direct freezing was performed at -20°C for all samples and stored for one week. Thawing conditions at both room temperature (25±2°C) and chilled (2±1°C) were done at 0, 1/2, 1, 2 and 4 hrs on the quality of frozen jackfruit bulbs. Both thawing conditions did not affect TSS, pH, AA content and TTA content except for texture. Control (T1) had a higher texture when compared to coated samples (T2 and T3). Thawing in the ambient temperature had a lower hue angle than the chilled condition. The significant changes in pulp firmness were observed after 2 hrs of thawing at both room temperature and chilled conditions. Fruit thawed in chilled condition had a firmer texture than ambient condition even after 4 hrs. It is recommended for the fruits to be consumed within 1 hr after thawing in the ambient condition. This study demonstrated that coating pre-treatment does not help to improve the taste and texture of frozen jackfruit bulbs by direct freezing.