All of us should keep a kitchen diary, showing how much food leaves our home uneaten, as garbage. We all waste food, you and me, every day, millions of tons of it. In China, enough food is wasted in restaurants every year to feed 200 million people. In the United States, 40 percent of food is wasted from farm to fork. Each year, the amount of food thrown away in rich countries is almost the same as that produced in sub-Saharan Africa. This raises some important questions.

In developing countries, food is lost because farmers do not have appropriate cooling, storage or market access for their crops. Their grains, fruits and vegetables wither and rot away. In developed countries, the picture is different, and food is wasted in supermarkets, restaurants and at home. China faces both syndromes, significant losses in farms, as well as at the retail and consumption stages. And the amount of food wasted by Chinese consumers is rapidly increasing.

In China, which didn't have a supermarket until 1989, annual supermarket sales have reached $100 billion today. The country will soon become the biggest consumer market in the world.