Squeezing Grapefruit on Shabbat

Hi,

One may not squeeze out juice from grapefruit sections on Shabbat by pressing them with a spoon. There is debate about sucking out juice, and one should be strict.

(Rav Moshe Feinstein, Igrot Moshe Orach Chaim 4:16)

Have a great day,
Mordechai