Usually one asks questions because they do not fully understand the topic. The answers I have been getting do nothing more than to generate new questions.
Perhaps you have some additional scriptural authority for the proposition that Christ's body is literally physically present in the Eucharist? Perhaps you have some scientific evidence that the elements have literally changed?
You've been given links to material explaining transubstantiation. You've been given simple explanation of sccidents and substance. This is surely not the first time for either of these.
Now, you can either read the material and pose a reasonable question, or you can continue to feign ignorance.
Perhaps you have some scientific evidence that the elements have literally changed?
Please study the subject of accidents and substance, then explain why this question is postulated on an erroneous inderstanding. Then we can begin discussing the topic.
SD