The universe in edible oil

The seven essential nutrients for the human body are protein, carbohydrates, fat, dietary fiber, vitamins, minerals and water, of which 50% of the total fat comes from edible oil. Edible oil is divided into animal oil and vegetable oil. Animal oil mainly refers to fats of pigs, cattle and sheep. Vegetable oils are classified according to the source of raw materials, including peanut oil, corn oil, olive oil, rapeseed oil, palm oil, sunflower oil and soybean oil. and many more. Different types of raw materials have different nutritional value of edible oil. According to different cooking methods, consumers need to choose edible oil according to their physique and other conditions. In order to make the best use of everything, it is good for health.

Lard under normal humidity is solid.

The pros and cons of cooking with lard
Bibimbap with lard, Chinese cabbage with oil residue, Yangchun noodles with lard… Add lard when cooking, and the taste of the food is instantly sublimated. The attractive fragrance mainly comes from the breakdown products of some special proteins and glycerides. Many people may have this kind of life experience: solid lard itself has no fragrance, but in the process of boiling lard or cooking with lard, it will produce a strong fragrance. This is because lard undergoes a series of complex chemical reactions at high temperatures, and finally generates some volatile organic compounds-lactones, such as γ-eneptolactone, γ-caprolactone and so on. These organics are small fragrance molecules captured by our sense of smell.

Rich fragrant lard residue. Lard residue is the solid that remains after the adipose tissue is extracted after lard is boiled.

In fact, the biggest feature of lard is rich in saturated fatty acids. Only when there is enough saturated fat, can the oil, starch and cellulose blend together well, and make the food taste more crispy and smooth. On the other hand, also because of the higher saturated fatty acid content and the better thermal stability of lard, lard is more suitable for high-temperature cooking methods such as frying and frying. However, although meals made with lard are very fragrant, excessive consumption will increase the level of low-density lipoprotein in the body, increase blood lipids and increase the prevalence of cardiovascular and cerebrovascular diseases.

How does cooking oil affect health?
The main difference between different edible oils lies in the different types and composition ratios of fatty acids, which also results in different nutritional characteristics, oil stability and flavor of edible oils. Fatty acids are divided into saturated fatty acids, polyunsaturated fatty acids and monounsaturated fatty acids. Studies have shown that excessive intake of saturated fatty acids will cause fat accumulation in the human body, leading to cardiovascular disease. The linolenic acid and linoleic acid in polyunsaturated acids are essential fatty acids for the human body, but if the intake ratio of linolenic acid and linoleic acid is imbalanced, it will also induce cardiovascular diseases. Monounsaturated fatty acids are beneficial to the human heart, brain, lungs, and blood vessels, and can prevent coronary heart disease and other diseases.

Soybean Oil: “Vessel Scavenger”
Soybeans, commonly known as “soybeans”, are native to my country, with the Northeast as the main producing area. Soybean oil is a kind of high-quality high-protein oilseed. Because of its good quality and low cost, it has become the most consumed vegetable oil in the world. In 2019, the consumption of edible vegetable oil in the United States reached 15.94 million tons, of which soybean oil accounted for 65% (10.36 million tons). Countries such as the United States, Brazil, Argentina, China and India are the main producing areas of soybean oil.

Soybean oil has a better fatty acid composition. Soybean oil is rich in linoleic acid, which has the effect of lowering serum cholesterol levels and preventing cardiovascular diseases. Soybeans also contain sufficient vitamin E and vitamin D, which are very beneficial to human health. In addition, the human body’s digestion and absorption rate of soybean oil is as high as 98%, so soybean oil is an excellent edible oil with high nutritional value. Soybean oil is also rich in lecithin. Lecithin is the basic substance of life, that is, an important part of the human biomembrane. It plays a key role in maintaining the physiological activity of the biomembrane and the normal metabolism of the body. It is known as the “vascular scavenger”. Supplementing lecithin by edible soybean oil helps beauty, brain and intelligence, and prevents fatty liver and liver cirrhosis.

Palm oil cannot be eaten in large quantities
Today, palm oil is almost ubiquitous in processed foods, but it is rarely talked about. In 2019, my country’s palm oil consumption was 6.46 million tons, which is the edible oil whose demand is second only to soybean oil and rapeseed oil. Due to its low cost and large output, palm oil has become a strong pillar of processed food.

The content of saturated fatty acids in palm oil is about 50%, and eating too much has the risk of obesity and cardiovascular disease. The raw materials of processed foods such as bread, instant noodles, pastries, ice cream, chocolate, potato chips and various biscuits are often marked with “plant-based fats”, but it is not specified whether it is palm oil.

Palm trees survive for a long time and are basically not affected by climates such as drought. Palm fruits can be harvested throughout the year to extract oil, so the oil production of palm oil is very stable. Under the same area, the output of palm oil is 10 times that of soybean oil. Therefore, palm oil is favored by food manufacturers or catering practitioners because of its low price.

In addition to consuming large amounts of palm oil, it is likely to cause obesity, but it may also shorten a person’s lifespan. The average life expectancy of Malaysians and Indonesians who consume palm oil all the year round is only 74 years and 70.7 years, ranking 70th and 114th in the world respectively; while Singaporeans who rarely consume palm oil before 2010 have an average life expectancy of 80.3 years. , Ranking 14th in the world (data from the World Health Organization).

Fresh palm fruit

Palm oil is commonly referred to as palm kernel oil, which is extracted from palm kernels (white part).

Bright prospects for canola oil
In my country, rapeseed oil is the largest self-produced edible vegetable oil, accounting for more than 50% of domestic vegetable oil. However, traditional rapeseed contains high levels of erucic acid and glucosinolates. Therefore, eating more rapeseed oil may induce myocardial fat accumulation, congestive heart failure and other diseases.

Canola oil is gradually replacing traditional rapeseed oil. Canola oil contains only 7% of saturated fatty acids, and the composition of unsaturated fatty acids in the remaining 93% is also very reasonable: oleic acid is about 65%, linoleic acid is about 20%, and linolenic acid is about 10%. Both linoleic acid and linolenic acid are essential fatty acids that cannot be synthesized by the human body. They are the main components for synthesizing cell membranes and biological enzymes. They play a decisive role in human health and intelligence. They are known as “lipid steward” and “brain gold”. “. In addition, canola oil is rich in polyphenols, of which phenolic acid content is the highest. In addition to helping to delay oil oxidation, phenolic acid also has important functions such as antibacterial, anti-tumor, anti-inflammatory and anti-viral activities. As a high-quality edible oil that takes into account both health and taste, canola oil has a very promising future.

Rapeseed, rapeseed and rapeseed oil.

The health value of coconut oil is overestimated
Coconut oil is an edible oil extracted from mature coconut meat. Its saturated fatty acid content is about twice as high as lard and tallow. Eating more is not good for cardiovascular and cerebrovascular health. Coconut oil was once touted as a “super food”, but in fact it is not. Some people claim that coconut oil can lose weight because coconut oil has a lot of medium-chain fatty acids, and medium-chain fatty acids can increase satiety, thereby reducing food intake, and it can be quickly oxidized and decomposed after entering the liver, so It does not cause fat accumulation in the body, so coconut oil has a weight loss effect. In fact, about half of the ingredients in coconut oil are short-chain fatty acids, so it does not have much effect on weight loss.

Coconut oil has a higher melting point and is solid at room temperature.

Another reason why coconut oil is sought after by some is “anti-dementia”. In fact, the key to the so-called coconut oil for treating dementia is also medium-chain fatty acids. The brain cells of patients with dementia can no longer obtain energy by metabolizing glucose, but the medium-chain fatty acids contained in coconut oil can be converted into ketone bodies (an energy source for brain cells in addition to glucose), which may enable brain cells to maintain their functions . However, although coconut oil contains medium-chain fatty acids, it also contains a lot of saturated fatty acids. In order to lose weight and treat dementia, if you take a lot of coconut oil, I am afraid that the gain will not be worth the loss.

The star of olive oil edible oil

As the “big star” in edible oil, olive oil has long been favored by the public. The ancient Greek poet Homer first hailed olive oil as “liquid gold.” The aroma of olive oil comes from its complex and diverse volatile organic compounds. Among vegetable oils, the fatty acids contained in olive oil contain a high content of monounsaturated fatty acids (about 73%), and monounsaturated fatty acids can reduce inflammatory factors in blood vessels and have a certain anti-inflammatory effect. The true “unique nutrients” of olive oil may be the polyphenol compounds in olive oil, such as hydroxytyrosol. Hydroxytyrosol is an effective antioxidant, and can reduce platelet aggregation, thereby avoiding thrombosis. This is the main reason why olive oil is beneficial to cardiovascular health.

Some people think that the smoke point of olive oil (the lowest temperature at which the oil starts to smoke when heated) is not high (190-200°C), so olive oil is not suitable for cooking. But in fact, high-temperature cooking often destroys the polyunsaturated fatty acids in the edible oil, and the polyunsaturated fatty acids in the fatty acids in olive oil account for only 12%, so the nutritional value of olive oil can be retained after being cooked. So, will the polyphenol compounds in olive oil be destroyed by high temperature? Researchers found that in cooked extra virgin olive oil, polyphenol compounds such as oleuropein and hydroxytyrosol were increased compared to uncooked oils of the same kind, indicating that the cooking process not only does not reduce the extra virgin olive oil The nutritional value of it will also increase the content of polyphenol compounds in the cooked dishes.

Corn oil is good for health but also cheap
Corn oil is bright in color and has a special fragrance. It is rich in protein, fat, carbohydrates, vitamins, linoleic acid, and trace elements such as iron, zinc, and selenium. The nutrition is relatively balanced. Corn oil also contains a lot of ferulic acid, and ferulic acid has strong antioxidant activity and cytoprotective ability, has a strong scavenging effect on free radicals, and can inhibit the enzymes that produce free radicals, and enhance the scavenging of free radicals. Enzyme activity. Therefore, proper intake of corn oil has certain preventive and adjuvant treatment effects on obesity, diabetes, cardiovascular and cerebrovascular diseases, Alzheimer’s disease and cancer.

Corn oil has a high smoke point, so it is not only suitable for cold dressing, cooking, but also for deep-frying. The fried food not only maintains the original flavor of the ingredients, but also does not lose the nutritional value of the ingredients themselves.

Corn oil has so many benefits, why is the price not high? Corn is one of the main crops in my country, and corn oil is mainly extracted from corn germ, with a high oil yield (the fat content of corn germ is as high as 80%). Corn germ is the useless part removed from corn in the process of corn starch production, so the use of corn germ to squeeze oil is a “waste utilization”.

The sunflower seeds used to squeeze oil are different from the melon seeds that we often knock. Sunflower seeds are smaller in size.

Sunflower seed oil-“Advanced Nutritional Oil”
About 400 years ago, sunflower was introduced to China from America as an ornamental plant. Unlike the melon seeds that we often eat, the sunflower seeds used to squeeze oil are smaller in size and contain higher fat content, so they have a more fragrant taste. Sunflower seed oil is rich in linoleic acid and vitamin E, which can remove garbage in the body, lower cholesterol, prevent hardening of the blood vessels and prevent coronary heart disease. It is known as the “high-grade nutrient oil”.

Affected by natural conditions and eating habits, 70% of the world’s sunflower oil is produced in Europe, with the main producing areas being Ukraine and Russia. Ukraine has the largest black soil belt on the earth. There is a long sunshine time and the soil is rich in organic nutrients, which is very conducive to the growth of high-quality sunflowers. Therefore, Ukraine is known as the “Sunflower Kingdom” and “European Granary”. Ukraine has about a quarter of idle arable land, and the cost of renting land to produce agricultural products in these areas is very low. In some areas of our country, the rent for 10,000 square meters of land is about 7,500 yuan, while in Ukraine it is only about 400 yuan, and the Ukrainian local government will also subsidize the planting of oil crops, which can basically offset the land rent. Therefore, local farmers plant oil crops. The cost of crops is almost zero, and high-quality sunflower seeds can be harvested only by inputting seeds and chemical fertilizers. The sunflower oil produced in Ukraine is of high quality and low price. 75% of the sunflower oil consumed in my country is imported from Ukraine.

Extracted peanut oil should not be consumed in large quantities
Peanut oil has a special peanut flavor and is a kind of edible oil commonly used by residents of our country. The ratio of saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids in peanut oil is relatively reasonable, close to 1:1:1, so it is easy for the human body to digest and absorb. The folk saying goes: “Eating peanuts often can keep you healthy.” Peanut oil retains a large amount of anti-aging substance in peanuts-resveratrol, and the content of resveratrol in peanut oil is as high as 25.7 micrograms per gram. Resveratrol is a natural polyphenol with strong biological activity. It is a natural chemical preventive agent for tumor diseases. It can also reduce platelet aggregation and prevent and treat atherosclerosis and other cardiovascular and cerebrovascular diseases. In addition, the integrity of human chromosomes will be destroyed as the body ages, and resveratrol can activate a protein (deacetylase) that repairs chromosomes, thereby maintaining the function of chromosomes to a certain extent.

Using physical methods to squeeze peanut oil will not destroy the nutrients such as linoleic acid and other unsaturated fatty acids and vitamin E, but the oil yield is low and the price is higher. There are trace chemical residues in peanut oil leached by chemical methods, which may cause cancer and destroy nutrients such as unsaturated fatty acids, vitamin E, iron and zinc. Although the oil production rate is high and the price is low, it is not suitable for large amounts of consumption. Therefore, the leached peanut oil is usually made into a blended oil together with some other edible oils.

Sesame oil is not afraid of low dosage
Sesame oil (sesame oil) is a very good condiment. It is generally used in cold dishes, various soups and hot dishes. Just drop one or two drops on it, and the food will instantly become fragrant and appetizing. Wide open.

Sesame oil is usually divided into two categories: one is small milled sesame oil, which has a strong fragrance; the other is ordinary sesame oil, which has a light fragrance. The fragrance components of sesame oil are very complicated. There are more than forty kinds of fragrance components that have been measured, the most important of which are sesamin and sesamol. Sesamol, which is produced by thermal decomposition of sesamol forest, is the main component of the aroma of sesame oil.

In addition to strong fragrance and good taste, sesame oil is also very nutritious. There are three main reasons why people don’t use sesame oil for cooking. First, the sesame oil is too rich in aroma, which will cover the original aroma of the ingredients, and the sesame oil heated at high temperature also has some strange smell. Second, the sesame oil is volatile. Even if you put a lot of it during cooking, it will evaporate a lot when heated at high temperature, and the fried vegetable will be very dry. Third, the price of sesame oil is high, and the cheaper one costs more than ten yuan per 500g, which is more expensive than the higher-priced pressed peanut oil among edible oils. In addition, sesame oil has a low smoke point, and high-temperature cooking will destroy its nutrients and generate free radicals, which will harm human health.

In different edible oils, the content of fatty acids has an important effect on dietary balance. The nutritional content of a single edible oil is not balanced, so different types of edible oils should be replaced. Moreover, no matter which kind of edible oil is chosen, the amount should be reduced, and it is not suitable to be reused.