STUDYING THE CHEMICAL AND PHYSICAL PROPERTIES FOR THE JUJUBE PLANT( ZIZIPHUS SPINA-CHRISTI ) FRUIT MOLASSES.

• Muna N. Khalaf

  Author

This study evaluated the quality of jujube (Nabq) fruit molasses produced via three distinct thermal evaporation and concentration techniques: Sample 1 (oven - concentrated at 50°C), Sample 2 (vacuum - concentrated at 70°C), and Sample 3 (direct heat - concentrated at 100°C). The findings demonstrate that the low temperature oven concentration method at 50 °C (Sample 1) was the most efficient and superior manufacturing model for producing jujube molasses. This technique achieved an optimal equilibrium by reducing the moisture content to 32% while increasing total soluble solids and total sugars to 68% and 48%, respectively. Furthermore, it recorded the highest viscosity (560  cP) and total protein content (6.56%), owing to the preservation of colloidal compounds and their protection against thermal denaturation and Maillard browning reactions, compared to vacuum concentration at 70°C (Sample 2) and direct heating at 100°C (Sample 3). The low - temperature treatments (Sample 1 and 2 ) also maintained the stability of the dry matter and mineral content of the fruits, which proved to be rich in essential elements, with potassium emerging as the element with the highest concentration (5,112 ppm in Sample 1 ), followed by calcium and iron, which decreased in the third Sample. Conversely, sodium (Na) exhibited an opposite trend, reaching its highest level in Sample 3 (298.1 ppm). Regarding vitamin content, the results revealed severe degradation and complete depletion of certain vitamins in Sample 3, such as vitamins A, K, and B9, because of heat-induced lipid oxidation. Vitamin C content dropped drastically from (209.607 to 31.004) ppm in Sample 1 and 3,respectively as a result of its high thermal sensitivity, whereas vitamin B3 exhibited remarkable stability. In terms of sensory evaluation, all Samples showed high consumer preference and acceptance without obvious processing defects. Sample 1 was best characterized by its texture, Sample 2 by its flavor, and Sample 3 by its light color, with Sample 1 receiving the highest rating in general acceptability (24 points). Ultimately, these results confirm that jujube fruit molasses processed under low-temperature conditions represents an excellent dietary source with high bio-nutritional value.

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