Read At Home with Chinese Cuisine Online
Authors: T P Hong
A standard Chinese wok has a bowl-shaped, rounded bottom with a sloping rim suitable for gas burners.
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The concave shape of the wok makes it easier to toss, stir, and mix food. It also allows the flames to wrap around the wok and go up the sides so as to give a larger cooking area inside the wok with a temperature gradient. The bottom of the wok is the hottest area, and the temperature goes down slightly further up the rim.
There are two practical aspects of cooking that illustrate the essence of using the wok: The wine and the vinegar are often added to the wok towards the end of stir-frying dishes and are drizzled in a circular motion onto the rim. The heat on the rim removes some of the alcohol from them and activates the volatile aroma molecules. After one more toss or mixing, the dish is ready to be served. Furthermore, the sloping rim allows the steam built up in the wok to escape comparatively easily – an element that contributes to the intensity of the flavour.
The conductivity of the material is a consideration when purchasing a wok. Carbon steel is commonly used to manufacture traditional woks and is popular because of its sensitivity to heat adjustment. The thicker its gauge, the more even the distribution of heat, but the weight can make holding and tossing unwieldy. Lighter woks with a thin gauge are available; they are easy to hold, but some of the very thin ones can warp and lead to uneven heat distribution.
The design of the handle is also worth noticing. The handles of the wok come in three designs: loops, stick, or the combination of both on the opposite side of the wok. A pair of bare metal loop handles mounted on the opposite sides of the wok can be found in old-fashioned kitchens that still use wood-burning stoves. It is more common these days to find the metal loops insulated with wood, bamboo, or heatproof synthetic materials to prevent injuries to the handlers. The wok with a stick handle is popular with people who have the habit of turning and mixing the food with the tossing motion. Insulated stick handles are mostly for the domestic kitchen, whereas metal stick handles can be found in the professional kitchen to deal with flying flames in high-heat cooking. I like the wok with an insulated stick handle and a loop; it gives me the flexibility of using it for tossing and holding both ends when the food is too heavy to be lifted with one hand.
A new wok needs to be “seasoned” regularly in order to allow the patina, a non-stick layer, to develop, and to stay rust-free. Sticking is caused by the formation of chemical bonds between the protein molecules of the food and the metal surface of the wok. The metal is porous and has microscopic, jagged peaks. Coating the surface of the wok with oil and heating it until hot results in the oil filling the cavities and rounding off the peaks. The cooking surface will develop a non-stick quality given time, so as to prevent water from seeping in to cause rust. Repeat the process of seasoning the wok regularly. The wok can be washed in warm water using a sponge or cloth, and then rinsed and dried immediately. It is recommended not to use the wok with patina for steaming. Boiling water in a wok damages the patina. The appropriate kitchen utensil for steaming is a steamer or a wok designated specifically for the task.
Apart from the regular seasoning, the wok should be seasoned every time you use it for cooking, especially for ingredients such as meat and fish that are likely to stick. The following sequence of seasoning the wok will prevent the food from sticking to the surface while ooking.
Heat the wok until when splashing drops of water into the wok, they rapidly skitter around the surface before boiling off | Add a tablespoon of oil and swirl it around to cover the part of the wok that will be in contact with the food. | Remove the wok from the heat and pour off any excess oil. |
The wok is ready to be used for cooking. Put the wok back to the heat source, adjust it to the desired level, add the quantity of oil needed into the wok, and heat the oil to the temperature required.
If you wish to use the same wok for the next dish, wash the wok in warm water using a sponge or cloth, rinse it, and dry it on the gas burner. A bamboo brush designed for scrubbing the wok can be used as well. Repeat the process of seasoning the wok before cooking the next dish.
In recent years, there have been research results showing the high rate of women suffering from lung cancer and respiratory diseases due to their exposure to cooking oil fumes.
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When the oil smokes, it begins to decompose. The chemical breakdown of the glycerol molecules in the fat and oil creates acrolein, an obnoxious-smelling compound that sticks to the clothes and hair and it is not good for the cook’s respiratory system. Apart from paying attention to the smoking point of the cooking oil, the Chinese TV celebrity chefs and nutritionists have been on a mission to convince the general public that stir-frying does not mean cooking with a very high temperature that causes the oil to smoke. They urge the domestic cook not to preheat the oil any longer than is necessary because the longer the oil is heated, the more quickly it will decompose. “Hot wok and cool oil” is the solution. Season the wok as described above. Put the wok back to the heat source, adjust it to the desired level, add the quantity of oil needed into the wok, and add the ingredient immediately without waiting for the oil to heat up.
When the Chinese talk about consuming food for health, YinYang(
營養
)is the phrase that springs to mind. This word consists of two characters, yin and yang. Yin as a verb is to pursue and to work towards. Yang as a noun connotes nourishing quality or nourishment; it can also be used as a verb meaning to nurture or to nourish.
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As a word, YinYang is used to mean “the pursuit of nourishment in life” for health and, for some, longevity.
SunSiMiao, a well-respected Chinese medicine doctor from the Tang Dynasty in the sixth century, gave advice to those in earnest pursuit of nourishment. It should start with paying attention to what you eat, he said.
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That is exactly what the majority of Chinese do, with a longstanding tradition of applying the principles of Traditional Chinese Medicine (TCM) to their daily dietary choices.
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The
Yellow
Emperor’s
Inner
Canon
(HuangDiNeiJing) is the primary source of reference for TCM and is the earliest Chinese text to offer dietary advice.
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Qi, yin and yang, the concept of correspondence between nature and human, and Wu Xing (the Five Elements Theory) are four of the conceptual foundations of the philosophical framework of the book. These four concepts have been brought into play in many aspects of Chinese life not only in food preparation but also in disease prevention and treatment, music, architecture design (FengShui), martial arts, and more. It is also in food preparation, which is relevant to our discussion here.
As we step into the world of TCM, we need to understand the fundamentals. First and foremost, it is the concept of Qi (
氣
). Qi is defined as “the basic element that constitutes the cosmos and, through its movements, changes and transformations, produces everything in the world, including the human body and life activities”.
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It is the invisible energy of life that is in a constant state of flux. The blowing of wind, the flow of water, and the change of seasons are all the manifestation of the energy maintaining the momentum of movement. For the human body, Qi is the intrinsic power or vital energy within us to keep our bodily functions going and sustain our lives. There is the innate Qi that exists from birth inside us, and there is the acquired (postnatal) Qi that is formed after birth from, for example, the food we eat and the air we inhale.
The second fundamental is the concept of yin and yang (
陰陽
).
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They are the opposite, yet interdependent qualities of Qi that interact and complement one another in a constant quest for harmony. They represent two inter-related aspects of one single phenomenon and their transformation into each other in the constant flow of the universe. Yin is the manifestation of Qi that is cold and dark; yang will then be the heat and light. An example is the perpetual cycle of day (yang) follows night (yin), and vice versa. For us human beings, when all of the yin and yang aspects of Qi are in harmony, we are thought to be in good health.
Daily Diet: Variety, Seasonality and Food Properties
There is a well-adhered-to dietary recommendation in
T
he
Yellow
Emperor’s
Inner
Canon
about incorporating multiple food sources in the daily diet for the maintenance of health. The text identified four food sources, each with five varieties of choices available at the time of the writing of the book. The four food sources are grains and pulses, fruits, meats, and vegetables. It suggests that grains and pulses, unrefined in those days, should be eaten as the staple for the nourishment of our body, accompanied by seasonal fruits as supplements. The meats have added benefits but need to be consumed in moderation. The seasonal vegetables play a substantial part in the daily diet to supplement and to keep one regular.
Multiple food sources and variety in daily food choices is one of the key messages here.
In recent years, the health benefit of having multiple food sources in our daily diet has been recognised by many governments and has been incorporated into the design of food pyramids that give dietary suggestions. The advice to have five-a-day, eight-a-day, or twelve-a-day is all about variety in daily food choices for a balanced diet.
From the perspective of TCM, a balanced diet is a diet that provides the body with balanced yin and yang energies in different seasons of the year. Having a variety of food sources is the first step in the right direction. One also needs to find out how the body reacts to seasonal changes and what natural produce one should be eating.
The concept of correspondence between nature and human (
天人合ㄧ
), articulated
in
The
Yellow
Emperor’s
Inner
Canon,
purports that the human body is an integral part of nature that mirrors the surrounding environment of the location in which we grow up and live, and so are the seasonal produce available at different times of the year. Our body is affected by the change of seasons. To alleviate our bodily discomfort at different times of the year, we often turn to seasonal produce that nature provides us. We are being encouraged to consume seasonal produce not just because they are at their freshest and most flavoursome, but also because many of them have the food property (food energy) that helps to maintain the balance of yin and yang in our body. Take the summer season as an example: it is the season that yang Qi reaches its peak. Consider a moderate increase in the consumption of natural produce with cool and cold properties, such as watermelon, in our diets to relieve heat inside our bodies in the scorching summer heat. Moderation is important; otherwise, overeating could lead to a yin-yang imbalance and cause bodily discomfort.
Seasonal produce has different food properties. We need to have the information to avoid overconsumption of food with more extreme hot and cold food properties.
The
Compendium
of
Materia
Medica
(
本草綱目
)
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is the major reference book that discusses in detail the five food properties (cold, cool, neutral, warm, hot) and their capacity to generate yin or yang energy inside our body. According to the book, food with cold and cool properties produce yin energy (yin Qi), and food with hot and warm properties produce yang energy (yang Qi). Food with neutral properties can be consumed all year round with no ill effects to one’s health.
Knowledge on food property also provides reference for the selection of matching ingredients in food preparation. In food preparation, different cooking methods can have varied degrees of impact on the food property of the ingredients. Steaming and simmering are said to have less impact, whereas deep-frying or baking is more likely to push the food property towards the warm or hot end of the spectrum. Eating too many deep-fried peanuts can cause a nosebleed because they have a warm to hot food property, depending on whether they are coated with batter. However, peanuts have a neutral food property when they are raw. Pears, which have a cold food property, are eaten fresh in the summer; the juicy and crunchy Asian pear is the fruit to go for when suffering from heat exhaustion. Pears steamed with wolfberry (with a neutral food property) or silver fungus (Tremella fuciformis, also with a neutral food property) and crystal (rock) sugar for a sweet dessert is said to neutralise the food property of the pears. This dessert dish is consumed to soothe dryness of the throat and to moisten the lungs.
Chefs often use more than one ingredient in a dish. The choice of accompanying ingredients can also reduce the more extreme impact of hot or cold food properties. Take the water chestnut as an example. It is a summer vegetable that has a cold food property, as with the majority of vegetables grown in water. A simple stir-fry dish of sliced water chestnut is deliciously crunchy and sweet, and it makes a nice occasional summer dish. However, people often add herbs such as spring onions with a warm food property for good measure. The consumption of seasonal food with a warm food property is most appropriate during the cold months of autumn and winter. Game birds are at their best in the autumn and the winter; most of their meats are believed to have a hot food property. Stir-frying their breast meat with black sesame oil and shredded ginger with its skin on, both with a hot food property, is tonic and warming in the cold months of the year to fend off the chill.
The food property information is commonly applied in Chinese households as a matter of course, and the learning process for the youngsters starts from daily activities. Fruit and vegetable vendors in the traditional market were my first teachers. I was trusted to fetch fruits and vegetables from the market when Mother was confident enough to set me loose in crowds. The vendors were always chatty and instructive, and they were very knowledgeable about food properties of the produce they sold, which was essential information provided as a part of their service. When I was asked to fetch loofah, for example, a small piece of ginger was always given for free. I was told that loofah is “cold” and that it is better to stir-fry with shredded ginger. Oranges (with a cool food property) are the seasonal fruit in the autumn, and they are rich in vitamin C, but I would be told by the fruit monger not to eat too many of them if I was seen coughing severely. Instead, the man would instruct me to have a piece of sun-dried persimmon.
By the time I was being taken seriously in the kitchen, Mother was my teacher. She said she first learned about food properties from her mother and grandmother. Her generation of housewife and mother was mindful of not repeating the same dishes often. A dutiful housewife always worked hard to provide variety and choices at mealtime. Through practice and experiment, she has accumulated a wealth of knowledge on food that my siblings and I have all benefited from.
Under her watchful eyes, I learned from my own experience as well, especially with fruit. I love lychees at the peak of their growing season. I could not have enough of them when family friends who lived in the countryside sent sackfuls of freshly picked lychees to our house every May. By the end of the week, my thumbnails would have turned brown from peeling the shells. I would have nosebleed, and my face would be covered with acne. I was told that lychees have a warm or hot food property. Overeating them in the summer heat is bound to cause problems.
Seasonal Dietary Adjustment: Variety, Seasonality and Moderation