Q. Is one allowed to puncture in Shabbos the small orifice opening of a cardboard ‘juice box’ container using the plastic straw provided?
A. Rabbi Ribiat (The 39 Melochos p. 838) and Rabbi Simcha Bunim Cohen (The Laws of Yom Tov p.191) permit puncturing the top of children’s juice box on Shabbat.
Rabbi Ribiat explains:
“The containers are disposable and usually discarded immediately after use. Puncturing the box to insert a straw is not Assiyas Pesach (creating an opening) because there is no need for a proper spout, but merely for a simple opening. The puncture-hole in the cardboard exterior of the carton is factory made; the interior foil lining that one punctures is thus comparable to a wrapper.” He quotes as a source the psakim of RS”Z Auerbach zt’l and Shmiras Shabbos K. (9: n. 10, 11). He adds that when possible the carton should be opened before Shabbos.Horav Shlomo Miller’s Shlit’a opinion is that it should not be opened during Shabbos.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a