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Abstract Ice cream is the most popular frozen dessert among children and adult in Egypt and the world. Using different ingredient especially the functional ingredients, flavours, probiotic bacteria, prebiotic ingredients and the modern equipments enables the manufacturer to produce different types and forms of ice cream which subsequently increases the production and consumption of ice cream. Ice milk contains relatively low fat (2-7%) and 12-15% milk solids not fat. The concept of functional foods evolved as the role of food in the maintenance of health. It is accepted that the functional food provides a health benefit that goes beyond the general nutritional benefit. In recent years, there has been a growing interest in production of functional foods. Dairy foods are a very important and popular products to consumers all over the world. It can be a useful tool play an important role as a functional product. Among all dairy products, frozen dairy desserts being the most popular products and can be a good vesical to carry up some nutritional components to work as functional products. Grapes (Vitis vinifera L.) are one of the most cultivated fruits in the world. In Egypt, grapes are considered the second main crop production after citrus, almost 200,000 Ton fruits/year. There are three main categories of grapes, namely wine grapes, table grapes and dried grapes. Grape is a rich resource of antioxidants including phenolic, flavonoid, and anthocyanin. Several health benefits are associated with the consumption of grapes and their derivatives. They are proposed to have protective vascular and antioxidant properties, in vitro and in vivo anti postprandial hyperglycemic activities, the ability to reduce the cholesterol levels as well as anticancer actions for several cancer types like skin, prostate and breast cancer. The majority of phenolic compounds in grape waste are flavonoids and phenolic acids which have been reported to have beneficial effects on the lipid metabolism. Grape pomace (GP) is the main byproducts results during grape processing, composed of skins, seeds and stems. The by-product of grape wine or juice industry weighing approximately 20% (w/w) of the grapes after pressing, is known as grape pomace. The health benefits of grape are largely attributed to its rich bioactive compounds, especially polyphenols, which mainly consist of proanthocyanidins, anthocyanins, flavonols, phenolic acids and stilbenes. The majority of phenolic compounds in grape waste are flavonoids and phenolic acids which have been reported to have beneficial effects on the lipid metabolism. Flavonoid intake has been inversely impact in relation to the coronary heart disease. Resveratrol is a major polyphenol compound in grape that is thought to be a potential contributor of several beneficial properties such as decreasing insulin resistance, preventing the heart failure and hypertension. It seems that grape byproducts have considerable potential as a useful component for improving the quality and longevity of dairy products. Additionally, the addition of grape by-products has various biological activities (e.g. antioxidant, antimicrobial, and anti-inflammatory effects) with potential health benefits. Dietary fiber is naturally present in cereals, vegetables, fruits and nuts. It is not digested by enzymes in the human intestinal tract, but part of it may be metabolized by bacteria in the lower gut. Dietary fibers are classified as soluble and insoluble fibers. It has crucial health benefit effects such as reducing of colon and heart related diseases, reducing diabetes incidence, gut reducing neoplasia, reducing the risk of colon cancer, preventing constipation and hemorrhoids, lowering blood cholesterol, regulating blood glucose levels for diabetes management, producing short chain fatty acids, increasing calcium absorption, stimulating the immune system and acting as prebiotics which enhance the growth of beneficial gut microflora. The technological properties of dietary fiber-enriched products are related to physiological function. For example, foods enriched with dietary fiber have increased water binding capabilities, swelling, retention capacity, oil holding, gel-forming, antioxidant capacity, viscosity texturizing, and stabilizing properties. As for antioxidants, they are substance that can prevent or slow down the damage resulting from the oxidation process that occurs within the human body, which results in an amount of free radicals. Antioxidants work to bind to free radicals and thus prevent the damage resulting from those redicals, which includes health problems such as heart disease, diabetes and cancer. Phenolic compounds (secondary compounds produced by plants are substances that have strong antioxidant activity, as they work to bind to free radicals and electron donors). Or hydrogen and bonding to metals preventing fat oxidation, preventing DNA damage, etc. The objectives of this study were to prepare pomace powder of black, red and white grapes, supplementing ice milk with these pomaces and to follow the changes of chocolate ice milk quality during their storage. This study has been carried out in four parts: Part I: Evaluate the chemical composition and functional properties of different grape pomace powders: White, Red and Black grape pomace powders were analyzed for the moisture, protein, fat, ash, crude fiber, carbohydrates, total phenolic compounds contents and antioxidant activity. Also, bulk density (g/cm3), water absorption capacity (g/g), swelling capacity (ml/g), oil absorption capacity (g/g) and solubility (%) of the three pomace powders were assessed. The results could be summarized as follows: 1. Red grape pomace powder (RGPP) had the highest moisture content followed by black grape pomace powder (BGPP), while white grape pomace powder (WGPP) attained significantly the lowest moisture content. 2. WGPP contained the highest fat content followed by RGPP and then BGPP. 3. There were no significant differences among grape pomace powder in protein and carbohydrate contents. 4. Black grape pomace powder contained the highest dietary fiber content followed by RGPP, while WGPP had the lowest dietary fiber content. 5. Black grape pomace powder (BGPP) contained the highest TPC content followed by red grape pomace powder, while white grape pomace powder exhibited the lowest content of TPC. 6. BGPP exhibited the highest antioxidant activity followed by RGPP, while white grape pomace powder showed the least antioxidant activity. 7. White and Red grape pomace powders exhibited lowest bulk density compared to black grape pomace powder which had the highest bulk density. 8. Black grape pomace powder exhibited the highest water absorption capacity followed by RGPP while WGPP exhibited the least water absorption capacity. 9. There were no significant differences in the swelling capacity of all the varieties of grape pomace powder. 10. Black grape pomace powder exhibited highest oil absorption capacity compared to both of red grape pomace powder and white grape pomace powder. 11. There were no significant differences in the Solubility (%) of all the varieties grape pomace powder. |