Taiwan Black Rice. Black rice has the highest nutritional value compared to the other varieties that we eat. Traditionally prized as a tribute to the emperors because of its scarcity, this low GI grain is high in proteins, and high in vitamin B, calcium, phosphorous and dietary fibre due to its bran layer that is retained during the harvesting process. Its vibrant black colour is full of antioxidant anthocyanin. A bowl of this rice has the same amount of anthocyanin in 200 kiwis, 200 cherry, 200 cranberries and 500 grapes! Cooking suggestion: Lightly rinse 2-3 times, soak in water with ratio of rice to water at 1:1.25 for 1-2h, thereafter cook in rice cooker ( use the same soaking water).