Different acidity and different cooking uses.

1. The degree of white vinegar refers to the alcohol content. Theoretically, the maximum degree is only 100 degrees, that is, the alcohol content is 100%. The acidity of 4-percent white vinegar is 4%, while the acidity of 9-percent white vinegar is 9%. That is, the acidity of 9-degree white vinegar is higher than that of 5-degree white vinegar.

2. Due to the difference in acidity, 9-degree white vinegar is more suitable for seasoning greasy foods, such as fried chicken, French fries, etc., and can effectively neutralize the greasy feeling. The lower acidity of 5-degree white vinegar is more suitable for cooking and pickling some tender ingredients, such as fish, seafood, vegetables, etc., so as not to overly suppress the original flavor of the ingredients.