I think that most great reviewers will always have some taste bias, and that will be part of how they review foods. If it was not for the individual pallet of each reviewer then it would not be a good review. It allows the reader to relate to the reviewer better and really get a sense for what they are tasting if they are good reviewer. The reviewer should always take their professional experience and knowledge with them and put it into every review they complete. As a reader you should almost be able to taste the food that the reviewer is writing about, almost smell the scents that the reviewer is smelling, and see the beauty of the delicious dish as well..
Personal taste preference is what makes your opinion a valuable opinion and what will set a great reviewer apart from an ok reviewer.