The "jelly" is one or more gums, typically agar agar or guar gum. They help keep the ingredients in wet food together. Some cats don't like the texture or flavor of it, which is fair since it's just a binder and not a natural part of a cat's diet.
So I understand exactly what you're asking, are you saying some cats only eat the chunks and not the "jelly" and you want them to? Depending on how much is left out of the chunks, it may not be necessary. Most of the nutrition is probably being eaten sufficiently. It's hard to say without seeing it.
Can you try a different type of canned food? Some cats like pate, some like gravy/broth based, some like the gummy/jelly wet foods, some like chunky. Cat are imprint eaters, often learning as kittens what to eat and what they like, making it difficult sometimes to feed them something different as adults/later.
Maybe try mixing the food well, incorporating the jelly into the chunks better?
Do you feed dry food as well? You could mix it in.
Try warming it up and/or adding water. This should thin out the jelly, making it more palatable if texture is an issue, then mix well. Warming it might enhance scent to make it more enticing.
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JessaMarie Ives
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