If your apple cider has started to fizz, taste tangy, or smell slightly boozy, it’s fermenting, and you don’t need to pour it down the drain. Naturally occurring yeast on apple skins can kick off fermentation even in the fridge, turning sweet cider into something closer to a mildly alcoholic drink. You have several good options depending on how far along the fermentation has gone.
First, Figure Out What You’re Working With
Fresh apple cider that has just begun to ferment will taste slightly fizzy and tart, with a faint alcohol bite. This is normal yeast activity converting fruit sugars into alcohol and carbon dioxide. If it smells pleasantly yeasty or like mild wine, it’s fine to use. If it smells strongly of nail polish remover, has visible mold on the surface, or tastes genuinely unpleasant, toss it.
Cider left to ferment fully can reach 4% to 8% alcohol by volume, similar to beer. Partially fermented cider sitting in your fridge for a week or two will be somewhere below that range. Children, elderly adults, and anyone with a weakened immune system should avoid drinking unpasteurized cider at any stage, fermented or not.
Drink It as Lightly Fermented Cider
If your cider is only mildly fizzy and still tastes mostly like apples, you can simply drink it. Many people enjoy this stage. It’s essentially a very young, naturally sparkling cider with low alcohol content. Chill it well and serve it over ice. The carbonation will be gentler than commercial hard cider, and the flavor will lean more toward fresh apple with a dry, slightly sour edge.
If you want to stop the fermentation where it is, move the cider to the coldest part of your fridge. Cold temperatures slow yeast activity dramatically. You can also heat the cider to at least 160°F on the stove, which kills the yeast entirely. This removes the fizz but stabilizes the flavor.
Let It Become Hard Cider
If you want to lean into the fermentation, you can let it run its course and end up with proper hard cider. Pour the cider into a clean glass jar or jug, filling it about three-quarters full. Cover the opening loosely with cheesecloth or a clean towel secured with a rubber band. This lets carbon dioxide escape while keeping debris out. Store it at room temperature, between 60°F and 80°F, out of direct sunlight.
Stir daily. Full alcoholic fermentation takes roughly 3 to 4 weeks. You’ll know it’s done when the bubbling slows significantly and the cider tastes dry rather than sweet, meaning the yeast has consumed most of the sugar. At this point, the cider will be cloudy. If clarity matters to you, let it sit undisturbed for a few days so the sediment settles to the bottom, then carefully pour the clear liquid off the top into a fresh container. Adding a small amount of dissolved gelatin can speed this up, pulling suspended particles to the bottom within 48 hours.
Turn It Into Apple Cider Vinegar
Vinegar is just the next step after alcohol. Once your cider has fully fermented into hard cider, bacteria convert the alcohol into acetic acid, which is what gives vinegar its sharp taste. If your cider has been fermenting for a while and already smells vinegary, nature has done some of this work for you.
To make vinegar intentionally, pour your fermented cider into a wide-mouthed jar (more surface area means more oxygen exposure, which the bacteria need). Fill it about three-quarters full and cover loosely with cheesecloth. Keep it at 60°F to 80°F, out of direct sunlight, and stir daily. A gelatinous disc called a “mother” may form on the surface. This is a colony of acetic acid bacteria, and it’s a sign things are working.
The full conversion from alcohol to vinegar takes another 3 to 4 weeks. Taste it periodically. When it reaches the tartness you want, strain it through a coffee filter to remove the mother and any sediment. This stops further fermentation. Bottle it and store at room temperature. Homemade apple cider vinegar works for salad dressings, marinades, pickling, and anywhere you’d use the store-bought version.
Cook and Bake With It
Fermented cider is a fantastic cooking ingredient regardless of where it is in the fermentation process. The acidity and complex apple flavor make it more interesting than fresh cider in many recipes.
- Braises and sauces: Use it in place of white wine or beer when cooking pork, chicken, or root vegetables. The apple flavor deepens as it reduces, and the acidity helps tenderize meat.
- Bread: Fermented cider can replace some or all of the water in bread dough. The wild yeast contributes to leavening, and the acidity gives the crumb a subtle tang similar to sourdough. Bakers who have tried this report good oven spring and a pleasant flavor.
- Pancakes and quick breads: The acidity in fermented cider reacts with baking soda the same way buttermilk does, creating lift. Substitute it one-to-one for milk or buttermilk in your recipe.
- Deglazing: Splash some into a hot pan after searing meat. It picks up the browned bits and creates a quick pan sauce with more depth than plain cider.
Heat destroys the alcohol and yeast, so any concerns about ongoing fermentation disappear once the cider is cooked.
Use the Vinegar Around the House
If you’ve gone the vinegar route, the finished product has uses beyond the kitchen. As a hair rinse, apple cider vinegar helps strip product buildup from the scalp and smooth the outer layer of the hair shaft, reducing frizz and adding shine. Mix 2 to 4 tablespoons of vinegar into 16 ounces of cool water and pour it over your hair after shampooing. Its mild acidity also helps rebalance scalp pH, which some dermatologists say can reduce flaking and dandruff by discouraging yeast growth on the skin.
Diluted apple cider vinegar also works as a natural cleaning solution for countertops and glass, though you should avoid using it on stone surfaces like marble or granite, where the acid can etch the finish.