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1. It is permitted to insulate cold items so that they should not become hot.
2. There is no prohibition of Bishul Akum for something that is normally eaten raw.
3. Tana Kama: While one may not start insulating food on Shabbos with items that do not increase heat, one may add insulation.
4. One may not crush snow or hail (or ice) on Shabbos in order to make it into water. Such water has the status of Nolad and is prohibited.
5. The Mishnah discusses which items one's animal may go outside with on Shabbos.
A BIT MORE
1. This applies both to cold drinks and foods that are often warmed up.
2. Accordingly, a Jew may drink water boiled by a Nochri, and there is no prohibition of Bishul Akum.
3. Raban Shimon ben Gamliel: One is even allowed to exchange the item used for insulation with another item. For example, if he does not want the contents to boil out, he may switch the insulating material for a material that allows more heat to escape.
4. However, one may put the snow or hail (or ice) into a cup or bowl of something (i.e. a drink) in order to cause it to be cold.
5. The general rule is that anything that protects the animal is considered part of the animal, and one does not transgress Shevisas Behemto (ensuring that his animal rests) by allowing his animal to go out with it on Shabbos. However, other items are considered loads and not part of the animal, and one transgresses Shevisas Behemto for letting his animal out with them on Shabbos.
Next Daf Index to Revach for Maseches Shabbos