Of course, its immediate application is as an experimental technology to feed hungry astronauts in space.
This is getting interestingly close to the fantasies of a Star Trek-style food replicator. Consumers go to the store, buy cartridges of nutrients and flavourings, load them into their printer, download some recipes from the internet, print, and eat.
It may be early to hypothesise about costs, but I hypothesise that 3-D printing foodstuffs may massively lower the costs — both in material inputs and in monetary inputs — of producing food.
For instance, today 70% of water usage is for food-related irrigation. Today it takes 1000 to 3000 litres of water to produce one kilo of rice, and it takes 13000 to 15000 litres of water to produce one kilo of grain-fed beef. So crops and animals take lots and lots of water to rear to the time they go onto human plates. Manufacturing food directly in a 3-D printer cuts out all the resources and energy involved in rearing animals and growing irrigating crops — so could massively cut down on water and resource usage.
Unfortunately, in this era of 2-D printing inks for inkjet printers are more expensive than fine wines. It has been jokingly said that the first thing many of those who experiment with 3-D printing will do is a print a 2-D printer that isn’t such an infuriating moneysucker. So printing at home is by no means guaranteed to lower costs or increase convenience. The technology is still in its nascency, and ultimately the results may be very poor, at least to begin with.
But in the long run, the cost-saving and resource-saving potential may win out. Perhaps 3-D food printing could be the innovation that does for human demand for agriculture what petrochemical fertilisers did in the 20th Century. At the time of Malthus, it was widely recognised that humans were oversaturating the land, that population was growing unsustainably and that it all had to end in starvation, cataclysm. This Malthusian fire and brimstone is once again popular today, with many true believers “doing the math” and declaring that human population growth is unsustainable, and some even suggesting forcible measures to prevent excessive population growth. But the first Malthusians failed to factor human innovation into their calculations. Fertilisers and other innovations in agriculture were black swans that derailed their predictions. In the long run, an innovation like food printing that massively reduces land use, water use and resource use could be the black swan that derails the predictions of modern Malthusians.
And with enough practice, recipes designed for 3-D food printers may turn into as much of an artform as recipes designed for regular ingredients and human labour. There will most likely aways be a niche for human-prepared and naturally-grown food. But music, video, books, etc, distributed via the internet are now of sufficient quality for widespread acceptance. With sufficient innovation, care, thought and experimentation it is possible that food (alongside various other 3-D printed goods) distributed digitally can reach acceptable standards.