You can look at the ingredient list on the package. How much buckwheat contains, and some of them are very small. For example, it says that buckwheat flour is more than 0.5, which is basically a "fake" buckwheat noodle. Because buckwheat lacks gluten, it is not easy to make noodles, which requires high production technology and formula requirements. These are all costs.
At present, the food standard of buckwheat noodles has not been formulated in China.
We can refer to the relevant regulations on buckwheat noodles in Japan first. The content of buckwheat flour in buckwheat noodles is above 30%, and the content can be omitted. More than 50% can be called high-quality grade.
According to this standard, when purchasing, pay attention to the proportion of buckwheat flour on the ingredient list or packaging, and you can pick better buckwheat noodles.