When it comes to seafood it's best to err on the side of caution. If you don't know if the crab meat was previously frozen then throw it in the garbage. Better to lose a few dollars to the garbage can than spend more at the doctor! The rule for seafood: If it's been previously frozen then don't freeze it again because of the potential for excessive bacterial growth. Remember, fresh seafood it only safe for about two days. If you desire to freeze it, do so on the day you buy it for optimum flavor and food safety to be retained. Just remember to freeze for a few days