The question arises in Halacha as to the status of Kosher food delivered by a gentile. For example, if a person orders food from a Kosher restaurant or pizza shop, and the food is delivered by a non-Jewish delivery boy, is the food permissible? From the Gemara it appears that if a gentile delivers Kosher meat, one must be concerned that the gentile may have substituted non-Kosher meat for the Kosher meat, and therefore the delivered meat may not be eaten. Would this mean that a Kosher restaurant may not deliver meat with a non-Jewish delivery boy? Is there a distinction in this regard between meat and other foods?
Chacham Ovadia Yosef writes (Halichot Olam, vol. 7, p. 171, Halacha 13) that meat may be delivered via a gentile only if it is wrapped in a double seal. Since one must tear open two seals to take the meat, any tampering of the package would be immediately discernible. Therefore, if the customer finds the meat with its double-seal packaging intact, he may rest assured that it was not tampered with and the meat is Kosher. This applies to wine, as well; one may allow a gentile to deliver wine only if it is packaged with a double seal. The Mashgiach (Kashrut supervisor) of a restaurant or store must ensure that meat and wine is packaged in a double seal before sent for delivery via a non-Jew.
If, however, one sends Yayin Mevushal (wine that had been brought to a boil) or dairy products, then a single seal suffices. So long as the food or wine was packaged with a single seal, it may be delivered via a gentile courier.
This Halacha applies as well to sending one's non-Jewish housekeeper to the store to purchase food. It is permissible to have her bring from the store sealed, packaged food, and one may have her bring meat or wine that is not Yayin Mevushal only if it is packaged with a double seal.
Summary: If a gentile brings or delivers Kosher meat, or wine that is not Mevushal, one may partake of the meat or wine only if it had been packaged with a double seal. For Mevushal wine or dairy foods, a single seal suffices.
