JINAN－Liu Qingnian may well be envied by many for having a "cool" job－his main assignment is to eat ice cream.

After graduating from Jiangnan University in East China's Jiangsu province in 1969, Liu, 75, spent more than two decades conducting research on edible natural pigment.

In 1997, he started to work at Jinan Qunkang Corp, based in Jinan, capital of Shandong province, engaged in ice cream research and testing, and now he is a chief engineer.

In 2008, an ice cream product named Shuang, a Chinese word meaning coolness, hit Jinan's market. In the city alone, up to 6 million pieces were sold every day. Liu was one of the main developers.

He says testing ice cream is like evaluating perfume, which is divided into top, heart and base notes. "The top note is felt via the tip of the tongue. The heart is the taste and mouthfeel of the melted ice cream. The base is the aftertaste."

As minor changes in the formula will lead to variations in taste, a tester must be familiar with all formulas and ingredients.

"It is not a 'superpower' of the tongue, but is entirely based on professional knowledge and experience," Liu says.

In order to ensure a sharp sense of taste, Liu rinses his mouth with warm water every time he tastes an ice cream, while he refuses any greasy or spicy food.

Ice cream products are usually developed in winter. During the busiest period, it is common to taste nearly 30 different ones a day. "After selecting raw materials and entering the research and development stage, it takes an average of more than 10,000 tests to finally determine the production formula," Liu says.

"Now I can probably guess the milk content and cost of an ice cream product just by taking one bite."

Despite his unbreakable bond with ice cream, Liu has always kept healthy with plenty of rest and a scientific diet to protect his stomach. He also enjoys jogging on a daily basis and mountain climbing.

With the improvement of people's living standards, the ice cream industry has also undergone new changes.

"Ice creams that contain fruits have begun to thrive in recent years, and low-sugar and low-fat products are more popular," Liu says.

"Guess who is the most envious of my job?" Liu jokes. "It's my granddaughter! She's jealous of all the ice cream I get to eat. After all, who could refuse such delicious treats!"