looking for a blueberry story

I can't remember the name of the story or the author. A girl finds herself and her friend at a candy factory but can't remember how she got there. She does know about the rooms in the factory and believes that if anyone breaks the rules bad things should happen to them. Her friend drinks from the chocolate river and blows up like a chocolate filled balloon and is taken away, but after that a lot of the other girls break the rules in other rooms but nothing happens to them. The girl is so put off by this that she demands to go to the inventing room, and once there she chews the three course gum and starts blowing up. Her inflation is interrupted when she finds out that the entire factory has been a special virtual tour, and something has gone wrong and she has blown up in the real world. There is no juicing room in the real world and her friend has already popped and she will pop soon too.

If any one has any info to share, I would appreciate it.