can we take food from home through security check to eat on board long flight to usa from Brisbane?
You can take food through US security.
Brisbane in your topic is Brisbane, CA since you are on the CA forum.
Here's the info directly from TSA:
You can click on the right to identify prohibited items. None of the prohibited items are food.
It depends entirely on the security rules in Brisbane. The TSA rules don't apply because TSA doesn't have authority in Austrailia.
For the US as long as it's not a jell-like substance I guess you can take it on board. Your fellow passengers may object if the food is aromatic (in a bad way). Don't know Oz rules.