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The U.S. is moving further away from slaughtering animals for human consumption. The Agriculture Department (USDA) approved the sale of lab-grown chicken in restaurants and grocery stores.

California companies Upside Foods and GOOD Meat received approval this week to begin shipping the lab-grown meat to restaurants, and eventually grocery store shelves.

The Food & Drug Administration (FDA) approved lab-grown meat in April.

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According to The Wall Street Journal, the process of growing meat from cells involves putting poultry and livestock cells into stainless-steel tanks known as bioreactors. The cells are fed nutrients and oxygen and quickly multiply (like bacteria colonies) before being harvested and formed into meat products.
 
RELATED: FDA Approves Lab-Grown Meat for Sale in US
 
Chefs at 2 fine dining restaurants in California and Washington, D.C. have already put in their orders for lab-grown chicken. Other restaurants can also begin serving the lab-grown meat to diners.

The lengthy time it takes to grow meat from single animal cells means it can’t be mass produced.

Lab-grown meat is so expensive that only the wealthy can afford to eat it.

So far, the meat is only available at fine dining restaurants in San Francisco and Washington, D.C.

The 2 California companies hope Americans will overcome their aversion to eating meat grown in a laboratory.

Upside Foods execs say the “slaughter-free chicken” is safe to eat. But a former employee said the company struggled for years to make enough meat in its bioreactors.

Upside Foods reportedly switched to growing meat in 2-liter plastic bottles. Hundreds of disposable bottles are required to make a few fillets of chicken.

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