Jiulihu buckwheat noodles with scallion oil are sour.

According to the Mint Food Network, buckwheat flour itself is an acidic food.

The acidic and alkaline states of soba noodles have different nutritional components and are suitable for different people.

Acidic soba noodles are rich in nutrients such as vitamins B1, B2 and unsaturated fatty acids, and are suitable for people who often stay up late and require a lot of mental work.

Alkaline soba noodles are rich in calcium, iron and other minerals, and are suitable for people who need to strengthen their bones and immunity.