If vinegar is frozen for long periods, it will also lose some of its acidity and flavor. That's why it is recommended that you only use previously frozen vinegar for cooking, except when you're pickling something.

Does Vinegar Freeze | Learn 28 Cleaning Uses for Vinegar

Does vinegar freeze? Commercial vinegar has a freezing point of about 28°F or -2°C, while its acidity means "self-preserving and does not need refrigeration.

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