The purchase of vinegar: When purchasing vinegar, the quality should be identified from the following aspects: First, look at the color, vinegar with red and white vinegar, high quality vinegar requirements are amber or reddish-brown or dark purple. The second is the smell of smell, high quality acetic acid flavor, no other smell. The third is to taste the taste, high quality acetic acid is high and non-irritating, soft sour, slightly sweet, not astringent, no other odor. In addition, good quality vinegar should be clear and transparent, with appropriate concentrations. No suspended matter, mold floating film. Vinegar from the factory, bottled vinegar within 3 months may not have a floating phenomenon such as mold floating flower, floating in the bulk of the 1 month may not have a floating phenomenon such as floating film.