According to www.startrek.com, a replicator is a device derived from transporter technology to dematerialize matter and then reconstitute it in another form.
Replicators were in use in Star Trek since the early 24th century, are most commonly used as food dispensers aboard Federation starships. The menu is only limited by the programming, as opposed to the days of carrying natural or reconstituted foodstuffs with delivery by special turbolifts or transporters.
The replicated food and "natural" food taste the same, though some people claim to be able to detect a difference. For instance, Captain Picard kept real caviar stored for special occasions since he felt replicated caviar was inferior to the real thing.
Well, that was science fiction, but Star Trek's food replicator may soon become a reality rather than science fiction. NASA revealed in May, 2013, that it was teaming up with Systems & Materials Research Consultancy (SMRC) on a 3D printer that can produce food. Right now the 3D printer can make a pizza. SMRC won a six month, $125,000 Small Business Innovation Research Grant from NASA to explore the probability of utilizing a 3D printer for food in lengthy space operations.
The senior mechanical engineer and founder, Anjan Contractor, went off and created a 3D food printer that utilizes long lasting powdered ingredients, individual vessels and containers (containing powder, water, oil) and heated plates (on the printer bed) to whip up a mini pizza in 12 minutes. Contractor notes that additional micro-nutrients can be added.
Next steps include FDA signing off on the process. If this succeeds, it will sure beat the freeze-dried food that astronauts have been dining on for decades. The significance could be even greater. Consider these words in a statement from SMRC: "By exploring and implementing technologies such as 3-D printing, this may avoid food shortage, inflation, starvation, famine, and even food wars." This could be something very positive for the future of our world!