According to NBC 4 consumer reporter Liz Crenshaw, the answer is in the brine.
Question: Are kosher pickles really kosher?
Answer: We turned to Pickle Packers International for this answer. It says that a “kosher” pickle may not be kosher in the sense that it has been prepared in accordance with Jewish dietary laws. Dill pickles are the most popular type of pickle... and “kosher” is a specific way that dill pickles can be prepared. In pickle lingo, “kosher” simply means that garlic has been added to the brine.
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