2,471. Prohibitions Designed to Impede Intermarriage

Maachalos Assuros 17:9

Other things are permitted under Biblical law but were prohibited by the Sages in order to distance Jews and non-Jews socially as an impediment to intermarriage. Accordingly, it is prohibited to drink with them even in a place where there’s no concern of libation wine. They likewise prohibited eating their bread or their cooking even in a place where there’s no concern of prohibited foods.

Maachalos Assuros 17:10

One may not drink at a non-Jewish party even if served boiled wine that is otherwise permitted and even if he drinks from his own vessels; if most of the people at the party are Jewish, then it’s permitted. One may not drink beer that they make from dates, figs, etc. in the place where it’s sold but one may bring it home and drink it there because the main purpose of this law is to reduce socialization.