Did the liquid drop? If there is a significant drop in liquid in your bottle compared to others, it means that the water in the drink is volatilizing, and at the same time, it means that there is a problem with its sealing, which is no longer tight. While evaporating, air is getting into the bottle, one, due to microorganisms or bacteria getting in and multiplying causing the drink to spoil. Secondly, some types of beverages can be oxidized and spoiled due to contact with oxygen in the air

Those fruity flavors are concentrated solids that are dissolved and mixed and then poured out,

Look at the process parameters on the package: uht instant sterilized, filled at 25°c.... If the process is well controlled, it shouldn't indicate a problem, and with a batch, there may be an occasional problem with a certain few products.

Your estimate may be the leakage of the mouth of the deterioration

This juice drink contains most of the pulp, easy to rot, a little bit of leakage can not be found in the future, the drink has a bad taste recommended not to drink again, some bacteria are very easy to cause disease!