Nutritional composition and characteristics of food

Yam is not only an important source of human starch and protein, but also has high health care value in traditional medicine, and its application range is very wide. Its fresh tuber contains about 16% starch and 3% protein, and also contains mucus, choline, glycoprotein, polyphenol oxidase and amylase, vitamin C, Dioscorea zingiberensis, Dioscorea polysaccharide, allantoin, various amino acids and minerals, dopamine hydrochloride and other chemical components.

Yam is sweet and belongs to spleen, lung and kidney. Its tuber is characterized by mucopolysaccharide, which contains flavonoids and diosgenin, and is the main active component of yam. Among them, polysaccharide contains carbohydrates and various reducing sugars, such as mannose, arabinose, glucose, galactose, fructose, a small amount of xylose and rhamnose, and protein.

The content of mucopolysaccharide and the intermolecular interaction of its components will affect the viscosity of tuber. Yam mucus can irritate some people's skin and cause allergies, but this allergic phenomenon can generally be washed off with soap or disappear naturally within 30 minutes, because yam mucus contains calcium oxalate crystals. In addition, yam is low in cellulose and fat.

Yam has high nutritional value and high viscosity. It is an excellent tonic food for people with indigestion, loss of appetite and weakness of spleen and stomach, and is very suitable for eating raw or cooking into various exquisite dishes. Because of the high nutritional value of yam, it can be used as both staple food and non-staple food, and can also be made into various exquisite foods.

The utilization of yam in health care function has been paid much attention, and its tuber is a natural gastrointestinal medicine, digestive medicine and hypertension preventive medicine. Yam tuber is a natural source of starch and protein, and it is rich in protein catabolic enzyme, sugar catabolic enzyme and various reductases, which can promote the digestive function. Mucopolysaccharides rich in tubers can be digested by enzymes to form a special dietary fiber, which can reduce blood cholesterol concentration, so it can be used as a preventive food for hypertension.

In the practical application of traditional Chinese medicine prescriptions, yam has long been used to eliminate fatigue, especially for people with decreased energy and weak constitution. In folk therapy, yam, as a surgical anti-inflammatory and repercussive drug, has a good effect on fire injury and frost injury. Chinese yam can be eaten after being heated with wine and salt, and can be used as a medicine for treating common cold and common cold.

Yam has always been regarded as a good tonic in Chinese herbal medicine in past dynasties. Other herbal classics, such as Shennong Materia Medica Classic, say that it is flat in nature, cool and moist in nature, sweet and nontoxic in taste, capable of invigorating spleen and stomach, nourishing lung and kidney, astringing essence, treating diarrhea, chronic dysentery, quenching thirst, fatigue, cough, nocturnal emission, frequent urination and eliminating phlegm. Commonly used folk medicine nourishes and strengthens the body. In the workshops, ancient famous names such as Liuwei Pill, Bawei Pill, Shen Ling Baizhu Powder, Wubushan Pill, Dashan Dioscorea Pill and Shen Si Decoction all contain yam.

According to the records of Chinese medicine, there are as many as 47 kinds of prescriptions made from yam. According to the names of ancient medicines, there are 333 kinds of prescriptions made of yam. At the end of the Qing Dynasty and the beginning of the Republic of China, Zhang Xichun, a famous doctor in Hebei Province, not only praised yam for nourishing blood and consolidating qi, relieving cough and asthma, and strengthening the heart and nourishing the spirit, but also pointed out that it is better to drink it with juice from living people, rather than frying it, because it contains a lot of protein. If it is fried, protein will be too dry to take it.

Clinical studies have confirmed that yam does have multiple effects such as stimulating appetite, improving digestion and strengthening physique. Yam also has the functions of lowering blood sugar, improving immune function, resisting oxidation and aging, increasing the weight of prostate and seminal vesicle in experimental animals and enhancing androgen. In a word, yam has high nutritional value, high viscosity, and a variety of healthy ingredients, which is very suitable for raw food, cooking or processing to make various exquisite yam products.

honey

Honey is a sweet substance that bees collect nectar or secretions from plants and store in nests and spleens after full brewing.

Honey has been enduring for thousands of years, which is related to its unique nutritional components.

The main components of honey are:

(1) About 65-80% of glucose and fructose can be directly absorbed by human body;

(2) Various amino acids, including 8 essential amino acids that cannot be synthesized by human body, account for about 0.3%;

(3) About 0.06% of more than 20 minerals are almost equal to those contained in human serum;

(4) More than 20 kinds of vitamins promoting human growth and metabolism;

(5) A variety of active enzymes.

In Compendium of Materia Medica, Li Shizhen described honey as "clearing away heat, tonifying middle energizer, detoxifying and relieving pain".

Honey can mainly prevent and treat:

(1) Gastrointestinal diseases: constipation, duodenal ulcer, colitis, infantile dysentery, etc.

(2) Nervous system diseases: insomnia and headache.

(3) Infectious wounds, burns and frostbite.

(4) beauty.

Some consumers think that honey is rich in sugar, and eating too much will lead to obesity, which is actually confusing honey with general nutrients. Honey is mainly composed of glucose and fructose, accounting for about 65-80%; The content of sucrose is very small, less than 5%. Because glucose and fructose can be directly absorbed by the human body, the absorption process is not accompanied by fat precipitation, so it will not cause obesity.

Honey crystallization is a purely physical phenomenon, not a chemical change, so it has no effect on its nutritional components and edible value, and crystallized honey is more convenient to store and transport. Crystallized honey often makes consumers mistake it for "molasses". Although destroying the crystal nucleus by high temperature heating can prevent honey from crystallizing, I don't know that the nutritional components of honey have been destroyed and there are no active substances!

However, honey mixed with white sugar does exist in the market. The difference is that sugar crystals are hard and difficult to melt by hand. But honey crystals melt easily by hand twisting.

The color of honey is directly related to the types of honey sources collected by bees, and the color of honey brewed by nectar from different honey sources is obviously different. Some people think that the lighter the color, the better the quality of honey. Indeed, acacia honey and some light-colored honey are very fragrant and of good quality. But longan honey, codonopsis pilosula honey and jujube honey also belong to the first-class honey. According to nutrition experts, the content of protein and iron in dark honey is about 50% higher than that in light honey. No wonder the British and Germans have a soft spot for black honey.

(1) Honey can be taken orally to treat pharyngolaryngitis, which has a miraculous effect on getting angry after staying up late.

(2) When mixed into various beverages and foods, it has elegant aroma and sweetness, but it should be noted that the temperature should not exceed 60 degrees.

(3) Taking concentrated honey after drinking can accelerate the decomposition of alcohol, eliminate headache after drinking and reduce the damage of alcohol to the liver.

(4) coating lips with honey can prevent the corners of the mouth from rotting; Using honey as a mask can make the skin delicate, smooth and elastic.

(5) Cooking and baking dishes with honey instead of white sugar have good flavor, color and nutrition, especially jujube honey used for roast chicken and roast duck, which is golden in color and unique in flavor. Try it.

(6) Taking honey half an hour before meals can stimulate gastric acid secretion, and it should be taken before meals because of atrophic gastritis (lack of gastric acid); On the other hand, taking honey two to three hours after meals can inhibit the secretion of gastric acid. If you have hypertrophic gastritis (hyperacidity), you should take it after meals.