Hi Melanie,
Welcome to the Moms Panel! Countdown is on, and these are the details that when thought about in advance, can make a trip much more enjoyable!
You will have access to these items at Sassagoula Floatworks and Food Factory, it is the food court located at Port Orleans French Quarter. There is a bakery section, as well as drinks and fruit options.
Another option would be to pre-order your groceries, through a company such as
www.gardengrocer.com, and have them delivered directly to your resort.
If you decide to simply use the food court at the resort, and find that it doesn't carry quite what you are looking for you could use the Disney transportation to go to one of the Disney Vacation Club Resorts (such as Saratoga Springs Resort or Old Key West) because their shops have a bigger selection of grocery items.
Hope this helps!