Walnuts soaked in vinegar usually need to be soaked for 1-2 months to allow the vinegar to fully penetrate into the walnuts and extract their flavor and nutrients. As for the choice of container, it is generally recommended to use glass jars, because glass jars will not chemically react with vinegar and can ensure purity and no odor during the brewing process. If you only have a plastic jar, make sure it is food grade and will not produce harmful substances due to the acidity of vinegar. However, you still need to be aware that the plastic can may have an odor that affects the final taste.

In addition, the walnuts should be completely submerged in vinegar when brewing, and the mouth of the jar needs to be sealed to prevent air from entering and causing mold. During the brewing process, you can shake the jar every once in a while (such as a week) to help the vinegar penetrate better into the walnuts.

Finally, soaked vinegar-soaked walnuts need to be stored in a cool, ventilated, dry place, away from direct sunlight and high temperatures.