What Is Vinegar?Vinegar is a product of the fermentation of alcohol by bacteria to produce acetic acid. The acetic acid is what gives vinegar its tangy flavor and also the ingredient that makes vinegar useful for household cleaning. Although you can use any alcohol for fermentation, you want to use ethanol to make vinegar you can drink and use in recipes. The ethanol can come from any number of sources, such as apple cider, wine, rice wine, fermented sugar cane, beer, honey and water, whiskey and water, or vegetable juice.
Mother of VinegarVinegar can be produced slowly from fruit juice or fermented juice or quickly by adding a culture called Mother of Vinegar to alcoholic liquid. Mother of Vinegar is a slimy, harmless substance consisting mostly of acetic acid bacteria (Mycoderma aceti) and cellulose. You can purchase vinegar (e.g., unfiltered cider vinegar) that contains it if you want to make homemade vinegar very quickly. Otherwise, it's easy to make vinegar more slowly without the culture. Any vinegar you make will contain Mother of Vinegar and can be used to produce subsequent batches of vinegar more quickly.
Slow Method Homemade Vinegar RecipeIf you're starting from scratch and not using a culture to speed the fermentation of alcohol into vinegar, your best bet is to start with an ingredient that contains a low level of alcohol (no more than 5-10%) and no added sugar. Apple cider, wine, fermented fruit juice, or stale beer make a perfect starting material. Regarding cider, you can start with fresh apple cider or hard cider. Fresh cider takes a few weeks to convert to vinegar because it first ferments into hard cider before becoming vinegar.
- Pour the starting liquid into a glass or stoneware jar or bottle. If you are using glass, try to select a dark bottle. Fermentation occurs in the dark, so you either need a dark container or else need to keep the liquid in a dark place. The advantage of a clear bottle is that you can see what is happening when you check the vinegar, but you need to keep it darkened the rest of the time.
- The fermentation process requires air, yet you don't want insects and dust getting into your recipe. Cover the mouth of the bottle with a few layers of cheesecloth and secure them with a rubber band.
- Place the container in a dark, warm place. You want a temperature of 60-80°F (15-27°C). Fermentation occurs more quickly at a warmer temperature. The length of time needed to convert the alcohol to acetic acid depends on the temperature, composition of the starting material, and availability of acetic acid bacteria. The slow process takes anywhere from 3 weeks to 6 months. Initially, the bacteria will cloud the liquid, eventually forming a gelatinous layer on the top of starting material.
- The bacteria need air to remain active, so it's best to avoid disturbing or stirring the mixture. After 3-4 weeks, test a small amount of the liquid to see if it has converted to vinegar. First, smell the covered bottle. If the vinegar is ready, it should smell like strong vinegar. If the bottle passes this initial test, unwrap the cheesecloth, draw off a little liquid, and taste it. If the vinegar passes the taste test, it's ready to be filtered and bottled. If you don't like the taste, replace the cheesecloth and allow the solution to sit longer. You can check it weekly or monthly if it's not ready. Note: a bottle with a spigot at the bottom makes the taste test much easier, since you can remove a little liquid without disturbing the Mother of Vinegar forming at the top of the container.
- Now you're ready to filter and bottle your homemade vinegar. Filter the liquid through a coffee filter or cheesecloth. If you plan to make more vinegar, keep some of the slimy material on the filter. This is the Mother of Vinegar and can be used to speed the production of future batches. The liquid you collect is the vinegar.
- Since homemade vinegar typically contains a small amount of residual alcohol, you may wish to boil the liquid to drive off the alcohol. Also, boiling the vinegar kills any undesirable microorganisms. It's also perfectly acceptable to use the freshly filtered, unpasteurized vinegar. Unpasteurized vinegar will have a shorter shelf life and should be refrigerated.
- Unpasteurized (fresh) vinegar may be stored in sterilized, sealed jars in a refrigerator for a few months.
- To pasteurize vinegar, heat it to 170°F (77°C) and maintain the temperature for 10 minutes. This can be achieved easily in a crock pot, if you don't want to babysit a pot on the stove and monitor its temperature. Pasteurized vinegar may be stored in sealed, sterilized containers for several months at room temperature.
Fast Method Using Mother of VinegarThe fast method is much like the slow method, except you have a culture of bacteria to speed the process. Simply add some Mother of Vinegar to the jug or bottle with the fermented liquid. Proceed as before, except expect the vinegar to be ready in days to weeks.
Vinegar with HerbsBefore bottling your vinegar, you can add herbs and spices to add flavor and visual appeal. Add a packed cup of dry herbs to a pint of vinegar. Pour the herbs and vinegar into a clear bottle or jar. Cover the container and place it in a sunny window. Shake the bottle once a day. When the flavor is sufficiently strong, you can use the vinegar as it is or else strain it and place it into fresh bottles.
Fresh ingredients, such as garlic, chives, and celery, may be used to flavor vinegar. Garlic cloves typically are too big to be fully preserved by the vinegar, so remove them after allowing 24 hours for it to flavor the vinegar.
You can dry fresh herbs to add to vinegar. Dill, basil, tarragon, mint, and/or chives are popular choices. Rinse the herbs and hang them to dry or else place them on a sheet of waxed paper onto a cookie sheet to dry in the sun or a warm oven. Remove the herbs from heat once the leaves start to curl.
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