Sign up for an Award
Participate with your entry in one of our professional or student awards.Sign up for an award
You are using an outdated browser. Please upgrade your browser to improve your experience.
Test paper is blue (alkalinity) before using the wrap. When food are put in the refrigerator, moisture will solidify on the wrap because evaporate. The test paper contacts the moisture will turn red (acidity) if the food was rotten.
Hsu-Tzu Cheng ,