1. Citric acid is added to Li Tang water, which is an acidic substance, which may bring some sourness and bitterness to the beverage.
2. Pyrimidine: The water in Yiquan Tang contains pyrimidine, which is a natural alkaline component and may also have a certain impact on the taste of the beverage.
3. Bitterness: Some people think that a spring of Litang water is bitter, which may be because it adds some bittering agents. Bitterness can increase the complexity and depth of drinks, but it may also make drinks more bitter.
Please note that the above information is for reference only, and the specific reasons may be different due to different product batches and production processes.