Opening Bottles and Cans on Shabbos
Question: Most bottle caps in use nowadays78 either leave a ring around the bottle neck or perforate along the edge when the bottle is opened. Is it permitted to open them on Shabbos or Yom Tov?
Discussion: This question is widely disputed among contemporary poskim. The debate centers around two basic issues. 1) Unscrewing a cap renders it a functional utensil, since before unscrewing it serves as a seal and it now becomes a cap which may be used as a cover.79 Thus, the first time the cap is unscrewed, it completes the formation of a utensil—the bottle cap—which may be a violation of Makeh b’patish.80 2) Unscrewing the cap at the perforated edge may be a violation of Mechatech, since the cap is being cut down to a specific size. There are conflicting views among the poskim in regard to the practical halachah:81
1. Some poskim prohibit opening all bottle caps that leave a ring or perforate along the edge. Some consider it Mechatech,82 while others consider it Makeh b’patish.83
2. Some poskim permit opening plastic bottle caps but forbid opening the ones made from metal.84 This is because plastic caps are functional even before they are screwed onto a bottle (as opposed to metal ones which—due to differences in technology—become operational only after being unscrewed from the bottle the first time). It is, however, important to note that technology and manufacturing methods can and do change with time. It is quite possible that certain types of caps which were permitted in the past [according to this view] no longer are; further research is needed.
3. Some poskim permit opening all bottle caps, since in their opinion neither makeh b’patish nor mechatech is being violated.85
Contemporary poskim are in agreement that it is forbidden to open bottle caps which are stamped with the date of production, etc., and the letter formation will be broken or erased when unscrewing the bottle cap.86
Question: Is it permitted to open a soda or tuna-fish can on Shabbos?
Discussion: In the opinion of Rav S.Z. Auerbach87 it is permitted to open both a soda can or a tuna fish can on Shabbos. He explains that Makeh b’patish does not apply to any utensil which will be discarded after its contents are removed, even if the contents are not removed immediately but will remain in the can for some time. In addition, he holds that Mechatech does not apply when lifting off a tab from a can of soda or beer, since one is not aiming to make a tab of a certain size, but rather to lift the tab off in the easiest way possible, which is where the manufacturer perforated it.
There are other poskim who forbid the opening of all cans on Shabbos for various halachic reasons—either because of Mechatech, Makeh b’patish or Soser.88 Those whose custom is to follow the more stringent opinion should continue to do so.89
78. Bottle caps which lift off with a bottle opener may be removed; Mishnah Berurah 314:17; Chazon Ish 51:11.
79. Even if the cap was partially unscrewed before Shabbos, but it remained attached to the ring, it is prohibited to unscrew it further on Shabbos; Binyan Shabbos, vol. 1, pg. 158; Meleches Shabbos, pg. 343.
80. See explanation of entire issue in Shulchan Shelomo 314:9-4, 5.
81. The same debate applies to plastic containers which are sealed with a plastic lid which is secured to the bottle by means of a plastic strip which is pulled off in order to open the container; see Binyan Shabbos, vol. 1, pg 108 and 246. See also Orchos Shabbos 12:20.
82. Rav Y.S. Elyashiv (Orchos Shabbos 12:18. note 31, Me’or ha-Shabbos, vol. 2, pg. 551).
83. Rav Y.Y. Weiss (Kol ha-Torah, vol. 42, pg. 14); Rav N. Karelitz (Chut Shani, Shabbos, vol. 2, pg. 274); Minchas Asher 1:28. One may, however, puncture a hole in the cap and then unscrew it; Shemiras Shabbos K’hilchasah 9:18, or better yet, puncture a wide hole in the cap and then pour the beverage through the punctured hole; Meleches Shabbos, pg. 344; Orchos Shabbos 12, note 30.
84. Shulchan Shelomo 314:9-9.
85. Rav Y.Y. Fischer in Even Yisrael 2:14; Tzitz Eliezer 14:45; Lehoros Nasan 7:21; Kinyan Torah 4:34; Yechaveh Da’as 2:42; Rav Y. Roth (Ohr ha-Shabbos, vol. 11, pg. 17).
86. See Mishnah Berurah 340:41, 519:11. See, however, Eliyahu Rabbah 519:6.
87. Shulchan Shelomo 314:7-4. Many other poskim agree as well; see Minchas Yitzchak 4:82; Chelkas Yaakov 3:8.
88. See Orchos Shabbos 12:5 and note 6 and 10 and Chut Shani, Shabbos, vol. 2, pgs. 273-274.
89. See Igros Moshe, O.C. 1:122, who in practice forbids opening all cans on Shabbos and Yom Tov, even though it is clearly permitted, in his opinion, according to the strict letter of the law.