Homemade Wine Slush Mix! 1 2/3 – 1 3/4 cups sugar (Less for if using a sweeter wine, more for a dry wine), 1 1/2 tsp citric acid, 1/4 tsp matcha (green tea) powder *optional. Measure all ingredients into a food processor. Pour 1 batch of mix into a 1 gallon freezer bag (or large bowl). Add 1 750 ml bottle of wine, and 3 cups of water. Stir/shake well. Freeze for about 3 hours before serving in glasses of your choice.