How can I help my husband while traveling without telling out tour group about his Alzheimer's?

My husband who has early moderate Alz and I have been traveling. I make all the arrangements, the packing, etc, etc. because he just don't have now the ability to decide on many things including what to wear on particular trip. And this is okey by him since a year ago. One of my problems is during group meals usually buffet. He gets confused on what to eat, and yet when I offer to get a plate for him of his favorites he refuses, that he ends up eating pastry and coffee only for breakfast or whatever vegetable or one item he first see on the table. Since I try to encourage him and suggest items that are good, and not raise any issue that would make him say something like "leave me alone" or something else, I keep cool by letting him eat what he wants (like mixing meat chunks with soup supposedly eaten on a plate with rice or potatoes, etc. and other combinations of different food items). I thought I was pretty brave to travel with him - getting lost, anal with restrooms, bottles of water where we were detained by TSAs in foreign countries because he would stash a bottle of water deep into his hand carry, although we have talked often of the liquid issue),the constant waiting, and waiting for him or going with him to the toilets, etc. But we always have fun! How could I diplomatically/lovingly help him with the meal situation with out him getting upset and me telling some folks in our tour group he has AD? I try to avoid doing this, but ended up telling someone in the last tour we did in Asia. But we are still going to travel. this is one activity we both like and I like to take him to a few more foreign places before he could not do it anymore, I would appreciate any tip, suggestions. Thank you. Deel