Scientists from the University of Missouri, the University of Maryland and the Animal Bioscience and Biotechnology Laboratory, US Department of Agriculture Agricultural Research Service have published an article in Nature outlining a method for "generating skeletal muscle efficiently from porcine induced pluripotent stem cells (piPSC) in vitro thereby providing a versatile platform for applications ranging from regenerative biology to the ex vivo cultivation of meat". The research used a porcine stem cell line to generate muscular tissue instead of cells taken directly from a pig:
"What the paper describes is research designed to generate muscle from a newly established pig stem-cell line, rather that from primary cells taken directly from a pig," co-author Dr. Nicholas Genovese, a stem-cell biologist (and vegetarian), told Digital Trends. "This entailed understanding the biology of relatively uncharacterized and recently-derived porcine induced pluripotent stem cell lines. What conditions support cell growth, survival and differentiation? These are all questions I had to figure out in the lab before the cells could be turned into muscle."
Also at GlobalMeatNews.
Enhanced Development of Skeletal Myotubes from Porcine Induced Pluripotent Stem Cells (open, DOI: 10.1038/srep41833) (DX)
I said water, energy, and land. As in the production can be done in a building covering 1% of the land area that would be required for raising cattle.
Later you noted that growing grains or alfalfa uses water. It also uses land--much more land, I would assume, than do feed lots.
> Low greenhouse gas emissions because there are no cattle FARTS.
Unless I'm mistaken, the bacteria that produce all that methane are the same bacteria that permit cattle to digest cellulose. We don't, AFAIK, have a practical industrial method of doing so (perhaps the same bacteria could be grown in a bioreactor, and the methane put to good use?).
Lacking a digestive system, cultured meat will need an industrially produced nutrient broth. There will also have to be replacements for the immune, respiratory, and excretory systems.
> http://pubs.acs.org/doi/abs/10.1021/es200130u [acs.org]
"Cyanobacteria hydrolysate was assumed to be used as the nutrient and energy source," they write in their abstract. I didn't view the full article, but I wonder how much of the predicted saving in land and water is due to that assumption. Cyanobacteria can grow in sea water, so it could be said that no land or fresh water is needed for its cultivation. The species Nostoc commune, which can grow in the ocean (or, I'm guessing, fresh water), is eaten by people.
http://lkcnhm.nus.edu.sg/dna/organisms/details/645 [nus.edu.sg]http://cuzcoeats.com/an-edible-bacteria-called-llullucha-finds-place-in-cuzcos-cuisine/ [cuzcoeats.com]https://en.wikipedia.org/wiki/Nostoc_commune#Uses [wikipedia.org]
article about using hydrolysed cyanobacteria to grow yeast: