As a professional nutritionist, in the kitchen decoration, the most important thing is to choose a powerful range hood, for reasons you may not imagine.
What is cooking fume?
The function of the range hood is to suck up the oil fumes produced during cooking, and the cooking fumes (COFs) mainly come from the volatilization and heating reaction of the cooking oil itself, as well as the reaction between the cooking oil and the various components in the food.
The composition of oil smoke is very complex:
- Whether a food contains carbohydrates, fats, or proteins can affect its composition;
- Cooking oil is made with soybean oil, olive oil, lard, butter or other oils that will affect its composition;
- Whether the cooking method is steamed, boiled, stewed, fried, fried, smoked, or roasted, will affect its composition;
- The length of cooking time also affects its composition.
According to the statistics of all the harmful substances produced in all cases, there are about 200 kinds, the most important of which are polycyclic aromatic hydrocarbons and aldehydes.
In addition, the components in the oil smoke are also divided into gaseous and particulate matter (PM), the main particulate matter in cooking oil is PM 10 and PM 2.5, PM 2.5 particles are smaller, and carry more harmful substances such as polycyclic aromatic hydrocarbons.
What are the health hazards of oil fumes?
Polycyclic aromatic hydrocarbons, such as benzopyrene, have been identified as a Class 1 carcinogen by the International Agency for Research on Cancer (IARC) under the World Health Organization.
It has also been shown that exposure to trans-2,4-decadienal (a type of aldehyde) will aggravate the genotoxicity of cooking fumes and promote the proliferation of human bronchial epithelial cells.
Inhalable particulate matter, such as PM 2.5, can be easily inhaled and deposited into the bronchioles and alveoli, which in turn affects the ventilation function of the lungs and induces respiratory diseases such as asthma and bronchitis.
In addition, studies have shown that cooking fume exposure is significantly associated with lung cancer, especially in the absence of a range hood. Epidemiological surveys of non-smoking women in China have shown that exposure to cooking fumes may increase the risk of lung cancer.
Looking at it this way, cooking fumes are really a big "health killer" for people who love to cook, do you say that I, a nutritionist, can I not pay attention to it?
3. How to reduce the harm of oil smoke?
1. Choose cooking oil reasonably
Whether a certain oil is easy to smoke or not will be professionally expressed by the word "smoke point"; The higher the smoke point, the less likely it is to smoke, so the higher the cooking temperature, the more important it is to choose an oil with a high smoke point. The specific recommendations are as follows:
- Frying and frying: high oleic sunflower oil, refined olive oil, almond oil, avocado oil, hazelnut oil.
- Stir-frying, roasting: grapeseed oil, extra virgin olive oil, tea oil, high oleic peanut oil.
- Low-temperature baking: corn oil, sesame oil, soybean oil, walnut oil.
- Coleslaw: flaxseed oil, wheat germ oil.
It is important to understand that the water in the food will enter the oil during frying, which will accelerate the hydrolysis of the fat and reduce the smoke point of the fat.
In addition, frying and frying are easy to produce harmful substances such as acrylamide and heterocyclic amines, and the oil suitable for frying is not cheap, and it is easy to gain weight after eating too much fried food, so it is better to fry less, my family can't make fried food once for several years, what about your family?
As for stir-frying, remember to use chopped green onions or garlic slices to roughly judge the oil temperature before serving, the specific method is: hot pan cold oil, garlic slices in the pot, a lot of bubbles around but no discoloration quickly dish, wait until the garlic slices change color or even burnt before putting the dish, it means that the oil temperature is too high.
It should also be reminded that you should not eat unrefined "earth-pressed oil", because it contains a lot of free fatty acids and has a relatively low smoke point.
Second, choose a high suction range hood
Let's first understand how the range hood removes the fume.
After starting, the rotation of the impeller of the range hood will form a negative pressure near the air inlet, which makes the oil smoke rise rapidly, the oil smoke does not directly enter the public flue, it flows through the filter screen to produce friction, the oil smoke separation, the separated oil adheres to the filter screen, and the accumulated more will flow into the oil cup, and the gas separated from the oil enters the public flue or returns to the room.
So how to choose a range hood?
Whether the way of fume emission is external or circulating, whether the shape is top suction or side suction, is not the most important, the most important thing is to pay attention to the four indicators related to suction.
➊ Air volume: The national standard requires an air volume of ≥ 10 cubic meters per minute, and the index of a range hood with large air volume can reach 20 cubic meters per minute.
➋ Wind pressure: The national standard requires a wind pressure of ≥ 100 Pa, and this indicator can reach more than 500 Pa for high-pressure range hoods.
➌ Normal odor reduction: This indicator reflects the ability of the range hood to reduce odor within 30 minutes, and the national standard requires that the index of the exhaust range hood is not less than 90%, and some range hoods can reach more than 98%.
➍ Instantaneous odor reduction: This indicator reflects the ability of the range hood to reduce odor within 3 minutes, the national standard requires that the index is not less than 50%, and some range hoods have an index of more than 80%.
In addition, it is necessary to pay attention to the two indicators of grease separation and noise, as well as the cleaning method of the range hood.
➊ Free separation: The national standard requires that the index is not less than 50%, and some range hoods have this index as high as more than 80%.
➋ Noise: The national standard requires that the noise is controlled at 73 dB when the air volume is ≥ 12 cubic meters per minute, and this indicator can be reduced to less than 50 dB for some range hoods.
➌ Cleaning method: generally divided into automatic cleaning and non-dismantling cleaning, if the separation of oil and smoke is good, it is more convenient to dismantle and clean, because only need to clean the filter screen and oil cup.
The range hood must be used well to better exhaust the fume and exhaust gas, five suggestions are as follows:
➊ Turn on the hood before firing.
➋ When using the range hood, open the window for ventilation.
➌ In addition to frying and stir-frying, range hoods are also used when steaming and stewing.
➍ After cooking, keep the hood on for 3 minutes.
➎ Clean regularly. Wipe down the surface after each cooking and clean the strainer and oil cup regularly according to usage.
To create a healthy kitchen, cooking nutritious and delicious, start by paying attention to what kind of oil to use and what kind of range hood to choose.