YOU SAID:

I didn't know that there was gelatin in meat!

INTO JAPANESE

私は肉にゼラチンがあることを知りませんでした！

BACK INTO ENGLISH

I did not know that the meat had gelatin!

INTO JAPANESE

私はその肉がゼラチンを含んでいることを知らなかった！

BACK INTO ENGLISH

I did not know that the meat contained gelatin!

INTO JAPANESE

私は肉がゼラチンを含んでいることを知りませんでした！

BACK INTO ENGLISH

I did not know that the meat contained gelatin!