One way around using food grade pumps is to seal the container and pressurize it with air so the pump never comes in contact with liquid. You can have some problems with pumps outgassing and contaminating the air, so I wouldn't rely on that method for a commercial product.
A much simpler way is to gravity feed the liquid. You can make pinch valves (like on school cafeteria milk dispensers) from a solenoid or a small R/C servo motor and only the tubing that comes in contact with fluid has to be food grade. That stuff is easy enough to find (and cheaper than food grade pumps).
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One way around using food grade pumps is to seal the container and pressurize it with air so the pump never comes in contact with liquid. You can have some problems with pumps outgassing and contaminating the air, so I wouldn't rely on that method for a commercial product.
A much simpler way is to gravity feed the liquid. You can make pinch valves (like on school cafeteria milk dispensers) from a solenoid or a small R/C servo motor and only the tubing that comes in contact with fluid has to be food grade. That stuff is easy enough to find (and cheaper than food grade pumps).