Mass-Free Food
The next generation of dieter's food beyond "fat-free" is "mass-free". These will be extremely light but strong edible structures made from freeze-dried agarose, the world's lightest solid material. The material is colored, flavored, and texturized to resemble bread, baked potato, etc. A "mass-free" hamburger on a bun will weigh only 1 gram. Don't put mustard or ketchup (preferred IUPAC nomenclature over "catsup") on it, because the water they contain will break down the structure of the freeze-dried agarose.

Restaurants
Direct brain-implant/virtual-reality technology will let people experience animal eating experiences. For example, you could directly experience what a cat feels when it catches and eats a mouse. Restaurants will specialize in particular eating experiences, for example they might have a yard populated by rabbits and a set of falcons. Or a large aquarium and some piranha.

Snack Food
In early 21st century, the most popular snack food will be Nacho Critters edible robots by Nabisco. Based mostly on a wheat-corn alloy, fried in zero-calorie non-fat vegetable shortening, these are little crisp chips shaped like gingerbread men, but only about 1 1/4 inches tall (that's 2.733 decihectares, for our Canadian friends). When you open the bag, the sudden exposure to oxygen activates their neural circuitry and locomotive machinery which permits them to walk around for a few minutes. Open the bag, and they slowly walk out, then proceed in random directions. Left to themselves, it creates a real mess because they get into everything! Then they "die", which causes problems if you got ants. It's fun to put the critters in a big jar with a stopper on it and watch them crawl over each other trying to get out! Dogs and cats love Nacho Critters!

Genetically Engineered Food
Soon it will be possible to transfer genetic material between completely different animals. The dream of a cow that gives chocolate milk is fast approaching reality. How will this boon be used? Probably we'll make many of the same combinations we do today in convenience foods for the microwave, except the food would be grown in a pre-mixed, ready-to-eat condition. Instead of buying frozen, you'll buy live! It'll taste much better than frozen because it'll be real fresh, the animal not actually dying until about 30 seconds after you hit START on the microwave. You won't ever have to worry about your Chicken Cordon Bleu leaking, because it won't have a seam. Advertising jingles can be genetically programmed into the brains of food. Just stick the food in the oven, and in the last few seconds you hear "M'mm m'mm good, m'mm m'mm good, Campbell's ChickeAAAACK!"

Cooking Shows
Advanced molecular replication technology will allow you to smell, taste, and even sample the food seen on cooking shows. They may also be used so that members of the audience can interact with the chef, sending him samples of their own recipes. And you can enjoy the same meal over and over again, just by popping the same tape in the TV. The TV and microwave oven are likely to converge into a single unit, responsible for both food and entertainment.

Food Scares
The one disease completely untreatable by advanced medical technology is hypochondria. The sick minds that invent food scares like the recent Alar hoax will need to become more sophisticated. For example, there will be rumors of software bombs implanted in food programming. These would range from just causing a case of gas, to making someone sick, to programming all the food animals to rise up at one time and take control of society.

Reuseable Food
A food flavor delivery system, consisting of a texture unit and rate-controlled flavor agent releasing system. It's sort of like a big piece of chewing gum, except the texture will be programmable (e.g., chewy like jerky, delicate and brittle like baklava, tender like meat). The flavor will also be programmable, by releasing different flavors in unique combinations. In fact, the flavor and texture can change while you're chewing it, so a complete meal with many courses can be enjoyed without even removing the device from your mouth.