I am not sure about a specific method but if you wish to have your sensory analysis done by the target age group (say 1.5 to 4 years) you can go ahead with Expression Bases Sensory. It will analyze the visual expression given after tasting your product. Ensure that clinical trials are done prior to test with an approval. The first expression the baby gives can be co related with standard face expression corresponding to specific preference level. I would forward if I get a related literature.
Sensory analysis is as deteiled and specific as analytical chemistry. So before you go ahead with any research, you have to clarify the goals of your project. What is the purpose of the development? Do you want to make a modification of a product, which already exists or launch a new one? The effet of the modification should be noticeable (e.g. more intense apple taste), or not (e.g. fortification with a vitamin, without unpleasant taste). Performing sensory tests with very young children is difficult. I can attach only a picture, which was used with children between 4-6 years. They had to drop the ball into the plastic cup, which represented their opinion.
Sensory evaluation should be done by the experts in food Sci., and technology but the babies should have other test for their food called acceptability test in order to start to improve the taste such category.
Doing sensory evaluation for the young children is difficult. You can use the Expression Bases Sensory. this determines the visual expression given after taking the food/product.