Buying packaged meat

Hi,

Normally, we do require that meat be watched by a Jew from the time of shechitah, to ensure that non-kosher meat is not substituted. There is great concern that someone might substitute non-kosher meat, since the product is identical and the kosher meat is more valuable.

Nonetheless, one may purchase meat from a supermarket where it has not been watched, so long as the package is sealed by someone who has been watching it, in a way that the consumer will be able to detect tampering, and the consumer is informed of what a properly sealed package should look like.

(Rav Moshe Feinstein, Igrot Moshe Yoreh Deah 1:56)

Have a great day,
Mordechai