Aaron SEIA - 7/15/2023 19:17
All the canning recipes I've seen call for 5%. I have no idea if 4% is not going to work. Haven't looked for any guidance from Extension or the USDA.
AaronSEIA
From Penn State Extension:
5% Acidity is the Gold Standard The standard vinegar used in home canning should be 5% acidity. Look at the label to be sure that the vinegar you are using is 5% acidity. Sometimes vinegar will be labeled as grain; 5% acidity is the same as 50 grain. Most white and cider vinegars used for making pickles and salsa are 5% acidity, but not all. Acidity level below 5% may result in spoilage as it is not adequate to control microbial growth. Only reduce the acidity when using a research-tested recipe that instructs you to add water to the product. Be aware the water in the food also dilutes the concentration of the brine. Some recipes direct you to soak cucumbers or other food product in salt water for a period of time before canning them in the pickling brine—this reduces the amount of water going into the brine.
As regards the post re: agricultural vinegar:
- Do not use cleaning vinegars or horticultural vinegars. These are EXTREMELY high in acid (11-30%), one is 75% acidity. These are not intended for food preservation.
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Vinegar
