Hi gentlep
I am not the best person to answer this question I don't have a special diet I am not a vegetarian I eat meat vegetables anything really!!! I nearly always have plenty of fresh mixed salad stuff with most things I eat, Lettuce, cucumber, several different colour peppers (the sweet bell type not chili), tomato, all as fresh as possible you name it I have it all chopped small and mixed together as part of my meal and I think that helps to keep my diet balanced.
You will find that as you move on with Yoga your body will tell you what you need you wont always listen to it I don't
... I love bacon egg and chips I cant resist Cornish pasties and I love porridge for breakfast.
If you eat vegetarian food the taste of the urine is very mild and pleasant. Very spicy hot stuff like curry (which I love) will effect the taste of your urine and so will a lot of red meat but you get used to that and the taste isn't necessarily an issue it doesn't seem to effect the effectiveness of the practice.
Having said that I dont eat huge meals the key is to eat Lightly and eat nutritious foods. I am turning to that more and more lately but diet is not necessarily a big issue with yoga as your inner silence rises you will learn to listen to your body it will tell you what you need.
Yogani's Little book "Diet Shatkarmas and Amaroli" is briliant if you havent already got it think about buying it it will answer all your questions.