Apple is a globally consumed fruit, both in fresh (63%) and processed (37%) form. Apple juice is a good source of vitamin C, which helps grow and repair body tissues. It also contains polyphenol compounds and soluble fiber, which can significantly reduce the risk of cancer, obesity, arteriosclerosis, and diabetes. Apple pomace, which is the leftover pulp after juicing, is also highly nutritious due to its high fiber content and bioactive compounds like polyphenols, flavonoids, and carotenes. Fiber is essential in our diet as it helps reduce the risk of diabetes, obesity, high cholesterol, blood fat, and cardiovascular diseases. Besides its nutritional value, dietary fiber has technological properties that make it useful in the food industry. It can form a gel, absorb water and oil, reduce water retention, increase viscosity, modify texture, and form and stabilize emulsions and foams. Studies have also shown that the technological properties of dietary fiber affect its nutritional properties. In this study, we aimed to use apple pomace powder as a source of fiber to enrich apple juice while also finding a way to prevent the accumulation of apple pomace waste. We eva‎luated the quality of apple pulp dried by four methods: normal oven, vacuum oven, microwave, and freezing. The eva‎luation considered the chemical composition and functional characteristics of each method, such as particle size, water and oil absorption capacity, antioxidant activity, phenolic compounds, anthocyanin, and color. We found that the freeze-dried sample was the optimal treatment for fiber extraction due to its high antioxidant activity, a significant percentage of phenolic content, high water and oil storage capacity, and transparency (L*). The insoluble fiber obtained from freeze-dried pomace did not show any significant difference in quality compared to pomace, so we used it to enrich apple juice due to its higher purity To enhance the fiber content of apple juice and prevent sedimentation, researchers used three concentrations of hydrocolloids tragacanth, carboxymethyl cellulose and pectin, individually and combined in ratios of 1:2, 1:3, and 1:4 - at 0.5%, 0.33%, and 0.25% by weight. The fiber concentration in all samples was kept at 1% by weight. The researchers tested the viscosity, suspension stability, acidity percentage, pH, soluble solid matter, mechanical turbidity, cloudiness index, and drink stability of the different formulations. The treatments containing tragacanth and a tragacanth-pectin mixture had the highest suspension stability among the 21 primary treatments. The treatments with 0.33% tragacanth and 0.5% tragacanth-pectin mixture performed the best in terms of cloudy index analysis and stability. To test the effect of time on the product stability, the researchers kept the best samples refrigerated for 16 days and analyzed them. The treatments containing tragacanth had the highest suspension stability, phenolic content, and antioxidant activity over time. The researchers recommend using treatments containing tragacanth to produce the product with the best performance.

اميرحسين گلي

صبيحه سليمانيان زاد , علي نيك بخت