Found this on Cancer.gov's website - taste issues

Taste Changes

Changes in how foods taste may be caused by radiation treatment, dental problems, or medicines. Cancer patients often complain of changes in their sense of taste when undergoing chemotherapy, in particular a bitter taste sensation. A sudden dislike for certain foods may occur. This may result in food avoidance, weight loss, and anorexia, which can greatly reduce the patients' quality of life. Some or all of the sense of taste may return, but it may be a year after treatment ends before the sense of taste is normal again. Drinking plenty of fluids, changing the types of foods eaten and adding spices or flavorings to food may help.

The following suggestions may help cancer patients manage changes in taste:

Rinse mouth with water before eating.
Try citrus fruits (oranges, tangerines, lemons, grapefruit) unless mouth sores are present.
Eat small meals and healthy snacks several times a day.
Eat meals when hungry rather than at set mealtimes.
Use plastic utensils if foods taste metallic.
Try favorite foods.
Eat with family and friends.
Have others prepare the meal.
Try new foods when feeling best.
Substitute poultry, fish, eggs, and cheese for red meat.
Find nonmeat, high- protein recipes in a vegetarian or Chinese cookbook.
Use sugar-free lemon drops, gum, or mints if there is a metallic or bitter taste in the mouth.
Add spices and sauces to foods.
Eat meat with something sweet, such as cranberry sauce, jelly, or applesauce.

Taking zinc sulfate tablets during radiation therapy to the head and neck may speed the return of normal taste after treatment.