The laws of Mifarek [separating grains and legumes from their peels and stalks] and peeling fruits and vegetables
The following section will deal with peeling shells/peels off of foods such as removing the pods/shells of nuts and beans and removing the peels of fruits and the like. Doing so in addition to involving the Borer restrictions, as well at times involves a prohibition of Mifarek or Dash, which is to detach an item from another item. The Mifarek prohibition is an offshoot of the Dash prohibition, and when it applies there is no permission at all to peel the item on Shabbos, even when done for right away use. This is opposed to the Borer prohibition which contains a leniency that it is always permitted to remove the good from the bad for right away use. Thus whenever the Mifarek prohibition applies the food may not be eaten on Shabbos.
 Based on Rama in end of chapter 321 Halacha 19, and alluded to in Admur here in Halacha 9. [see Shabbos Kihalacha Vol 2 page 290]