Starting with bovine stem cells, the Dutch researchers have grown muscle fibres up to 3cm long and 0.5mm thick. The fibres are tethered and exercised as they grow, like real muscles, by bending and stretching in the culture dishes. They feed on a broth of vegetable proteins and other nutrients, equivalent to the grass or grain diet of cattle.
At present the fibres are a pallid yellowish-pink colour, rather than the red of raw ground beef, because they do not contain blood, but Prof Post plans to improve their appearance.
Hopefully not by adding a bunch of dye to it.
The comments on the linked article are disappointingly luddite (and predictably smug and preachy in the case of the vegetarians/vegans), but they did prompt me to wonder just how “natural” such synthetic meats might end up being. It’s a fair point that if you’re eating all the hormones and such required to grow the meat in vitro, it’s probably going to be less healthy for you than the real thing.