Apple cider vinegar is one of the most common forms of vinegar on the market. It may not be used in a lot of Filipino foods, but it can be a good substitute for other vinegars if you just don't have them on hand. The flavoring will be a bit different, but the overall recipe should still work out. If you want to make your own cider vinegar to use in a Filipino recipe, the process may be easier than you think. Here is a basic guide that you can follow.
Step 1 – Prepare the Mixture
Mix apple cider with beer yeast to allow the product to ferment. If you do not have apple cider on hand, you can make it by pressing fresh apples and straining out the juice.
Step 2 – Ferment the Vinegar
Leave the liquid in a room that will stay between 60 and 80 degrees. This is the ideal temperature for fermentation. It would be wise to leave the container uncovered if you can, but you may want to put a porous towel on top to prevent bugs and dirt from getting in. Do not cover the dish completely as it will need air to form the bacteria that make's vinegar acidic. You can use mother of vinegar to speed up the bacteria forming process, but the mixture will create its own in time.
Wait three to four weeks for the fermentation process to complete. The mixture will start to smell like vinegar at this point, so just taste it until it reaches a flavor you like.
Step 3 – Strain the Solution
Use a coffee filter to strain the vinegar several times to get out all the mother of vinegar. If you do not do this, the fermentation will continue and ruin your batch. Once all of this is complete, you can pour the vinegar in jars and refrigerate it.
Note that the recipe above may not be suited for preservation. Homemade vinegar does not always have the right pH balance to preserve food, and it can actually cause food poisoning in some cases. You can use this in dressings or marinades, but don't use it to preserve your food. Store it in the refrigerator between uses.
If this does not work out, you can always use a store-bought Filipino vinegar instead.