TOP chefs source the freshest ingredients from wet markets selling everything from greens and vegetables to a virtual menagerie that crawls, scampers, flies, swims, trots or otherwise gets around. Gao Ceng goes for a stroll with Chef Sam.

Grimy wet markets, piled high with fresh, wet and wiggling produce - things that swim and crawl, snap and scuttle, sometimes jump, flop and hiss, sometimes squeal, quack and flutter - are sublime pilgrimage sites for gastronomes.

Forget the smells, the slippery floors, the blooded chopping blocks, the red gutters, the sounds of cleavers smashing into bone and flesh, the piles of discarded fish guts, feathers and other innards.

Forget the crowds of shoving shoppers and vendors jammed together, shouting and bargaining. Make way for the new trolleys of fresh fish or crustaceans, or tiny wild birds desperate to escape from their baskets.

Ah, drink it all in - the sights, sounds, the smell, the touch, the taste - and imagine that out of all this commotion will come magnificent feasts.

Renowned chefs such as Alain Ducasse, among many others, make it their business to check out fresh wet markets for their restaurants to ensure their produce is the freshest and most seasonal and interesting. Visits are adventures not to be missed and many an expat gets hooked, so to speak.

Shanghai has three main types of food market - indoor markets managed by the government, unlicensed wet markets and wholesale markets.

Indoor markets, open from 6am to 6pm, generally cover 1,000 square meters in the center of a residential area. It's clean and well organized; many vendors provide abundant produce, attractively displaced. Shopping is a comfortable experience. Most products come from wholesale markets so the quality and supply is steady and uniform, which prices are relatively higher.

Wet markets, also called roadside markets, are known for being crowded and often dirty; the food is very fresh and the prices are cheaper. They are often criticized for occupying public space and slowing down traffic.

Every morning around 4am, fruit, vegetable, fish, meat and other hawkers start selling their products from tricycles on the road, generally lining the main street. From 7am to 8am, streets are flooded with customers, mainly people in the neighborhood. Markets close at around 10am.

These roadside markets charge no rental fees and attract many suburban farmer selling fresh-picked greens and vegetables. Poultry is taken to market alive and slaughtered (illegally) on the spot. But for many Chinese who consider freshness the No. 1 issue, wet markets are still their first choice.

Downtown, there are two popular wet markets, one on Zhejiang Road M., the other on Xiangyang Road N.

Two large wholesale markets near the suburbs sell high-quality food at competitive prices, 20 percent cheaper than the average in most markets. One is Cao'an Wholesale Market on Wuning Road in Putuo District, selling all kinds of greens and produce as well as meat, poultry and fish. The other is Tongchuan Road Seafood Market, also in Putuo District.

Market culture

Some Shanghai housewives willingly make the trip.

"I go there (Cao'an Wholesale Market) once a week and usually buy lots of vegetables and dried food that last for a long time - both for my family and neighbors who cover my transport fee," says Zhang Xiaopei, a middle-aged shopper.

Shoppers at Tongchuan Seafood Market not only buy seafood but also enjoy meals since dozens of nearby restaurants feature seafood. Diners can order from the menu or ask the chef to prepare seafood they have already purchased.

Shanghai has a distinctive market culture, a little slice of life, but nowadays shoppers seldom wear pajamas, which used to be very popular, and most don't wear rollers in their hair anymore.

Woven shopping baskets were once necessary; they were replaced by plastic but are again becoming popular since shoppers must pay for plastic.

All vendors throw in some spring onions, typical in Shanghai cooking, to built customary loyalty.

Bargaining is typical, even though the prices are quite cheap already. Vendors may cut 10 percent of the price, and sometimes 50 percent, depending on the item for sale and the shopper's bargaining skills.

It's advised to dress simply, because prices go up when hawkers see well-dressed customers.

Many chefs including Michelin-starred celebrity chefs Alain Ducasse and Jean-Georges Vongerichten say an important source of their inspiration comes from food markets where produce is fresh and seasonal.

This week, we take a suburban market stroll in the Pudong New Area with Sam Gao, Chinese executive chef at Pudong Shangri-La Shanghai, known for his Shanghai and Huaiyang cuisine.

He shares some of his sourcing experience, introduces special local ingredients and describes how to cook them at home.

"Compared with big supermarkets, I prefer shopping at food markets since the food there are fresher and cheaper," the chef says.

At the entrance gate of the Dongchang Road Market, there's usually a large stall of green vegetables; around 80 percent are said to be locally grown to ensure freshness.

Seasonal ingredients like caotou (草头), a kind of clover blossom, and Chinese cabbage are displayed prominently. The vendor keeps spraying them with water to keep them fresh.

Chef Sam says the caotou is now very tender and fragrant. Shanghainese usually fry it with baijiu (白酒, distilled liquor) or made it into caotou quanzi (草头圈子) - caotou braised in soy sauce with pork intestine - a typical Shanghai dish.

Two kinds of Chinese cabbage are available; the greenhouse variety is large and light green in color. The cabbage grown outdoors has dark green leaves with some white spots.

"I recommend buying those grown outdoors and harvested after the first frost; they have glutinous texture and natural sweetness and can be fried simply at home," the chef says.

Shanghainese tend to add sugar when frying to bring out the cabbage flavor.

One month later in spring, the market will sell local wild greens from rural Chongming County and Qingpu District, such as malantou (马兰头) or Indian aster, and gouqi tou (枸杞头) leaves of wolfberry.

Some greens are available all year, such as jicai (荠菜) or shephard's purse, which is often made into wonton; watercress, often fried with dougan (豆干), a kind of dried tofu with a firm texture.

There's a wide range of colorful, appealing vegetables, including red tomatoes, white turnip, carrots, Chongming gold melons, purple eggplant, red cabbage and white cabbage.

Vendors often provide simple cooking suggestions on which vegetables to combine and how to prepare them.

Near the vegetable stalls, there are usually vendors selling tubors, such as potato, Chinese yam, taro, water chestnut and cigu (慈姑), the bulbus corm of the aquatic sagittaria.

Many old Shanghainese love cigu shao rou (慈姑烧肉), the corm braised with pork, in cold winter. Cigu or the corm itself doesn't contain strong flavor but has a flour-like texture, which highlights the pork's meaty flavor and helps absorb the grease, says chef Sam.

Next comes the butchers' stalls where various cuts of pork, beef, mutton and lamb are displayed; cured ham and preserved sausages are hung up. Internal organs are displayed on the side, including feat, hart, lungs, liver, trip, intestines and other innards.

Pig's lung soup and fried pig's heart are quite popular and believed to be healthy. In traditional Chinese medicine an animal's heart is considered beneficial for the human heart, likewise for a pig's lung.

The stalls are always lighted in the sunny morning to make the red meat look redder and glistening. Some butchers post the daily specials.

"Lately the meat from hei mao zhu (黑毛猪), a domestic black pig, is popular," the chef says. "It has fine texture, rich flavors and a unique fatty fragrance, which makes a good Shanghai-style braised pork."

The poultry area is usually the biggest since it's filled with live chicken, duck, goose, pigeon and other fowl. They are placed in large cane cages and taken back into a kitchen to be slaughtered and drained and cut up as the customer wants.

Chicken is the most popular. Those of different ages are best for different dishes. Lao muji (老母鸡) or older hens, with rich flavor, are used for chicken soup; caoji (草鸡) or spring chicken, with tender meat, is made into congyou ji (葱油鸡), fried chicken with spring onion in hot oil.

Shanghai is known for its san huang ji (三黄鸡), a chicken with yellow feather, beak and feet traditionally raised in Chuansha Town, the Pudong New Area. It's often made into steamed chicken and chicken congee due to its fine and tender texture.

Chef Sam advises picking your bird and asking the vendor to kill and clean it in the back kitchen in 15-20 minutes. That gives you time to buy vegetables and other ingredients during the waiting time.

The aquatic products area is wet, slippery and bloody. It's usually in an area separate from other drier produce.

Seafood and fresh water products are sold separately in different ways. Fresh water products including fish, shrimps and shells are sold alive. They are placed in tanks or vats with oxygen supplying equipment.

One fish seller says locals prefer bai shui yu (白水鱼), a kind of white snapper, usually steamed with spring onion; jiyu (鲫鱼), a carp often made into soup or fried with spring onion; and luyu (鲈鱼), a weever that can be either steamed or braised in sauce.

Chef Sam says most of the freshwater products are from Dianshan Lake in west Shanghai's Qingpu District or Qiandao (Thousand Island) Lake in Zhejiang Province.

He recommends fish from manmade Qiandao Lake.

"The manmade lake used for a hydroelectric station has clear water quality. More importantly, the aquatic grasses provide balanced nutrition, which gives the fish a rich but not earthy taste," he says.

He recommends choosing wild fish that are dark in color, with a firm touch.

Various seafood

Various raw seafood are placed on ice, including hairtail, large yellow croaker, large prawns and many others.

"Shanghainese love braised hairtail in soy sauce, or salt it first and then deep fry it. I will help customers cut it into 5cm sections at home so it's easier to cook," says one vendor.

Large yellow croaker is rare thus expensive, the chef says. "But it's savory if steamed or made into soup. It's one of my favorites."

Soybeans can be processed into many products with different flavors, aromas, textures, shapes and colors. All are available in markets.

Commonly sold are tofu, baiye (百叶), a thin-sliced dried bean curd used to make soup; kaofu (烤麸), an honeycombed product and local specialty often braised with mushroom and peanuts; you mian jin (油面筋) or wheat gluten, a hollow spherical product with golden color that can be stuffed with meat.

Sellers of grains and cereals display sack of grain in the traditional way - in sacks, with wooden signs bearing the name, variety and production area.

Besides the rice are sacks of beans, millet, barley, sorghum, rye, peas and seeds. Some are arranged according to color, ranging from white rice and light-colored grains to golden millet and corn, green mung beans, red beans, back beans, black glutinous rice and sesame. Some are arranged according to the size of the grain.

Chef Sam recommends eating more black beans, black sesame and black rice in winter since traditional Chinese medicine claims that eating black-colored foods in winter supplies energy and "tonifies" the kidney. They are traditionally prepared in congee for breakfast. Locals often add pickles, fermented or dried vegetables and fruits and marinated condiments.

Each market has at last one seller of pickles and condiments of all kinds, some briny and spicy in northern style and some with a certain sweetness in southern style. There are many samples for tasting.

Older people prefer sweeter condiments while young people like spicier tastes, says one vendor, adding that everybody likes zhacai (榨菜), mustard stem salted and rubbed with chili.

Cucumber, radish and lettuce are commonly used to make pickles since they are juicy and crunchy. Garlic marinated with sugar and vinegar has a sweet and sour taste and is also popular.

Locals prefer wet markets not only for freshness and cost, but also for their wide range of street food. These include world-famous Shanghai snacks such as youtiao (油条), deep-fried dough, and shengjian (生煎), pan-fried dumpling with meat filling. There are others - hard to find elsewhere - but more likely to be on sale in wet markets.

Bao jiao bu (包脚步) literally means the cloth used for wrapping feet, quite unappetizing. It is actually youtiao together with pickles seasoned with tian mi jiang (甜蜜酱), a thick brown-colored sauce made from wheat flour and soybean featuring sweet and briny taste. It's wrapped in a thin layer of egg cake to resemble the food cloth. The cake tastes chewy and the inside is crispy with a strong aroma.

You dun zi (油墩子), a kind of deep-fried golden brown pastry, is filled with shredded white turnip and diced spring onion. It was once popular in the city but now is only found in wet markets. It has a crunchy skin and crispy filling with a mild taste; it's served hot.

Jiuniang bing (酒酿饼), a thin steamed cake with a soft, fluffy texture, is moderately sweet; it's made by mixing flour and jiuniang, a sweet mildly alcoholic unfiltered wine. During autumn, some vendors add sweet osmanthus to the dough, imparting a flowery fragrance.

Some popular old snacks relied on traditional skills and were very time-consuming to prepare; nowadays there are few places to find them - wet markets are a good place to hunt.