1.   B. the length of time any food residue remains on the teeth.

2.   - Wash silver by hand as soon as possible after eating to remove food residue.

3.   Make sure the jar rim is clear of any food residue before putting the lid in place.

4.   The girls were unclean, with food residue around their mouths.

5.   Later, inspectors in Detroit found refrigerated food stored above acceptable temperatures and pots, pans and other dishware soiled with grease and food residue.