run something into something. 1. to guide or route something, such as a wire or a pipe, into something or a place. The worker ran the circuit into each room. He ran in the circuit as specified. 2. to guide something into something; to drive or steer something into something else.
A change of color to a blue-black or purple color suggests that starch is present. If there is no change in color, this suggests no starch is detectable. Note the change of the iodine to black on the potato (right) but not the apple (left). (10% Tincture of iodine.) Potato contains starch, but apple does not.
The iodine test solution is best kept in a small eye-dropper bottle clearly labeled starch test, obviously. Perfoming an iodine test. So much about the science. In brewing an iodine test is best done on a piece of white chalk or drywall. In my own brewing I use a piece of white sidewalk chalk that I took from the kid's bucket of chalks.