Hilchot Shabbat 21:15-16 (Juice that emerges from the fruit on its own)

We learned that squeezing an olive or grape for its juice on Shabbat is a Torah prohibition, whereas squeezing other fruits that are typically squeezed for their juice is a Rabbinic prohibition. What happens, then, if juice emerges from different types of fruit on its own? May a person drink it on Shabbat? If not, must he throw it out?