Clean and sterilize the bottles if you reuse them for your next homemade wine project.  It ensures no harmful bacteria can interrupt your winemaking process and cause spoilage and disease.  Here’s how:  Clean Your Bottles Use a cleaning solution for wine bottles because detergents can contain chemicals that alter winemaking.  You can fill a sink with cleaning solution and hot water, then let the bottles soak for an hour.  Use a small and long brush to clean the insides before rinsing them with hot water.  Make sure to reach all the solid debris so it cannot mix with your wine and cause problems during winemaking. Sanitize Your Bottles Sanitizing your wine bottles can eliminate the remaining microorganisms that may remain during the cleaning process. If you skip this step, your wine can be prone to contamination and spoilage, which you want to avoid. Use a sulfur pump that contains sulfur dioxide gas and water that can kill microorganisms.  Drain Your Bottles Let your bottles drain and dry by placing them in a rack upside down to let any solution flow out of the bottle.  Ensure it is completely dry before using, as moisture can introduce bacteria to the wine and cause spoilage. Fill With Wine After sanitizing, immediately fill the bottle with your wine to avoid contamination if you delay this process.  It would help to use a cork to ensure an airtight seal and prevent oxygen from entering the bottle. Use a siphon hose or funnel to pour the wine, leaving a few spaces on top to expand the wine during aging.