These are the fruits of the rattan (𝘊𝘢𝘭𝘢𝘮𝘶𝘴 𝘮𝘢𝘯𝘪𝘭𝘭𝘦𝘯𝘴𝘪𝘴) displayed on a trade fair at the Benguet capitol. It's known locally as "littuko". It's very acidic and it's considered as one of the sourest fruits in the world.
You can eat it as is (raw). They are also commonly preserved and pickled. Some use it as a souring agent when cooking soups and stews because of its intense tartness.
