If one has a mixture of okhel and psolet, he should separate them in the easiest way possible, so as to minimize exertion on Yom Tov. Thus, if most of the mixture is okhel, he should remove the psolet, and if most of the mixture is psolet, he should remove the okhel (Beitza 14b).
On Shabbat, some maintain that it is prohibited to peel fruits and vegetables with a peeler, even if the peels are edible (Peninei Halakha: Shabbat 11:8). In contrast, on Yom Tov one may peel all fruits and vegetables, even those with inedible peels. On Shabbat, one may not remove olive pits with a device specifically designed for this purpose (ibid. 11:7), whereas on Yom Tov he may. On Shabbat, many adopt the strict view and avoid removing bones from fish or meat before eating them (ibid. 11:7); on Yom Tov, all agree that bones may be removed before the meal.
On Shabbat, one may not spill out the liquid from a can of corn or peas or the oil from a can of tuna (ibid. 11:13); on Yom Tov this is permitted. On Shabbat, one should not use a slotted spoon to separate food from the liquid in which it was cooked (ibid.), but on Yom Tov this is permitted. On Shabbat, one may not use a colander to drain water from pasta, nor may one separate the broth of a soup from pieces of food in it, and it is certainly prohibited to use a strainer to do so (ibid. 11:12); on Yom Tov, all of these actions are permitted (SSK 4:6).
Just as it is permitted to separate food for Yom Tov needs, so too it is permitted to separate clothing, utensils, or game pieces (Or Le-Tziyon 3:19:7).
As we have seen (3:8), whenever it is possible to prepare food before Yom Tov without compromising the taste of the food, any melakha involved must be done before Yom Tov. Nevertheless, if it was not done before Yom Tov, it may be done on Yom Tov with a shinui. The shinui does not need to be a major one. For example, if a plate is the surface that one generally uses for separating, he should use the table or some other surface (SHT 495:10).
. The Sages prohibited straining mustard in the normal way with a strainer even if one wishes to eat it on Yom Tov, since this is usually done for the long term. Similarly, they forbade making cheese, which involves adding a starter culture to milk in order to separate the curds from the whey. If it is truly necessary to strain mustard or make cheese for the Yom Tov meal, it may be done with a shinui (Shabbat 134a; SA 510:3, 5; MB 12:21).