In 1932, Winston Churchill predicted that "fifty years hence we shall escape the absurdity of growing a whole chicken in order to eat the breast or wing, by growing these parts separately under a suitable medium."
Tissue engineering is a rapidly evolving field of study. It has resulted in successful skin grafts for victims of burns or severe abrasions, and the simplest of replacement organs, namely bladders. The technology that is currently used can infuse stem cells into a matrix of dissolvable scaffold material, cultured in an oxygenated nutrient bath.
More experimental work seeks to denude a more complex organ, like a donor heart, of all living cells, and to repopulate the extracellular matrix with stem cells from the intended host. Hearts, lungs, livers, kidneys, digestive organs, and muscle are all candidates for engineered "autografts," or allowing people to grow their own tissues and organs to replace failing systems, with minimal risk of immune rejection.
Similar techniques are being explored for generating animal muscle from stem cells for human consumption. In theory, the opportunity exists to grow meat in culture much more efficiently than on farms, and without cruel treatment of animals, crude application of hormones or antibiotics, excessive saturated fat or cholesterol, or environmental contaminants such as mercury or PCBs (the latter most relevant for seafood).
What are the technical hurdles? Thick muscle tissue requires vascularization. Muscle tissue also currently requires loading, stretching, and microscopic tearing for growth (this is how weightlifting makes people muscular, and why your muscles are sore two days after a workout). Also, tissues are highly dependent upon the major organ systems of the body for nutrition, respiration, immunity, and nervous and endocrine system regulation.
Growing sushi or a rib eye steak in a vat will happen, no doubt about it, and there is a huge market for this "clean\ source of food.
But is it 'vegetarian' if no animals are harmed?
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