India, June 5 -- About 20 years ago, my parents visited my tiny first apartment in Chicago and they couldn't have been prouder. Watching their daughter busy, content and working as a consultant with an insurance firm filled them with joy. But there was one part of my new life they simply couldn't accept: that I cooked once, and reheated many times.

They hated the idea of me eating refrigerated food from a day or more ago.

"Why can't you make something fresh?" my father would complain.

"It tastes fine. Just try it," I would plead. Absolutely not, he said each time.

Over the years, as work intensified and my children arrived, I continued to refrigerate leftovers unapologetically. As I began to study food chemistry and nutrition, I learn...