In the historical context of that time, mussels and mulberries were not the most unpalatable foods, but common agricultural products.

In ancient China, Henan and Hebei were areas rich in rivers. River mussels were a common ingredient there, and mulberry trees were also common in the south. Mulberry is the fruit of the mulberry tree and is also a common fruit.

Yuan Shao's army was in the Hebei area, and local mussels were a relatively common food ingredient at that time. Yuan Shu's army was in the Jiangnan area, and local mulberries were also a relatively common food ingredient.

Although these foods were different from today's diet, they could have been a main source of food at that time.

Therefore, mussels and mulberries were not the most unpalatable foods, but were relatively common agricultural products at that time, while steamed buns and pancakes were some common grain products.