Many people in America love Chinese food, but David R Chan is perhaps in a league of his own.

Mr Chan, a 72-year-old former tax lawyer based in Los Angeles, claims to have dined at nearly 8,000 Chinese restaurants across the US and counting.

Though his food journey started as part of a search for his identity as a Chinese American, Mr Chan said, over the years it has become itself a chronicle of the rise of Chinese food and changing dynamics of Chinese culture in America.

"The food was not sophisticated," Mr Chan recalled of his first Chinese meals in the 1950s.

Chinese food was first cooked in the US by Chinese immigrants who came dreaming of wealth during the California Gold Rush in the mid 19th Century.

By the time Mr Chan had his first tastes of chop suey, there were relatively few Chinese Americans in the US - 0.08% of the total population - most of whom were descended from Toisan.

"My interest in the history of Chinese in the US led me to eat Chinese food and see what it was like to be Chinese in different parts of the country.".

During his long career as a tax lawyer, Mr Chan often sampled Chinese food on his business trips to far-flung states in the US, as well as Canada and Asia.

"The fried rice was like boiled rice, and somebody poured soy sauce on to it," Mr Chan said.

Before the recent boom, the event that put Chinese food into the American public consciousness can be traced to a presidential visit in 1972.

Nixon's visit "prepared for another stage in the development of Chinese food in the US," said Yong Chen, a history professor at University of California, Irvine and author of Chop Suey, USA.

Today, there are over 45,000 Chinese restaurants across the US, more than the number of McDonald's, Burger King, Kentucky Fried Chicken and Wendy's outlets combined, according to an estimate by the Chinese American Restaurant Association.

And because Chinese restaurants are almost always among the few places open on public holidays like Thanksgiving and Christmas, they have become the refuge of those averse to cooking the big family meal.

For Mr Chan, this trend presents a bonanza of new Chinese restaurants to "collect"?

But one of his followers remains sceptical about his expertise - his wife, who is from China and is bemused that people ask Mr Chan about Chinese food.

What I learnt eating at 8,000 Chinese restaurants