Hi Hatice,
Having your sense of taste altered during treatment is a potential side effect of some chemo therapies. It is important to maintain good nutrition during treatment, so I hope you will be able to keep eating good foods as best you can. Here are some tips I am aware of to help with this:
Try high nutrition beverages (such as protein drinks) and drink them from a closed container using a straw.
Rinse your mouth before eating. American Cancer Society’s website suggests a rinse containing one teaspoon salt, one teaspoon baking soda and four cups of water, and you should shake the mixture well before rinsing.
Eat foods that are cold rather than hot.
Use different seasoning than you are accustomed to, e.g., try different spices than is your custom, or add lemon juice or sweeteners to your food, or sauces such as catsup, or eat salty foods.
Avoid metal utensils.
Between meals, suck on sugar-free hard candies or chew gum.
I hope some of these tips work for you. Take care, regards, Mary