Regarding some judgment questions about food chemistry, I am very grateful to ask the experts to ans

Flip through the book.。。 You must not have taken your class seriously.

It's been many years since I graduated, and I've forgotten about it, a lot of specious things, and I can't judge ——-

You won't understand why you know the answer, so I suggest you ask your teacher or friend and ask them to explain it to you.

Carbohydrates, fats, proteins, dietary fiber, vitamins.

1. Carbohydrates:

Carbohydrates, the most economical and main source of energy for human beings, are able to provide and store heat; It is an important substance that makes up the body's tissues, maintains the energy necessary for brain function, and participates in the composition and various activities of cells.

2. Fats: Lipids have important biological functions. Fat is the energy provider of living organisms. Lipids are also important components of living organisms, such as phospholipids are important components of biofilms, and oils and fats are the storage and transportation forms of fuel required for body metabolism.

3. Protein:

The material basis of life, organic macromolecules, the basic organic matter that makes up cells, and the main bearer of life activities. There is no life without protein. Amino acids are the basic building blocks of proteins, substances closely related to life and various forms of life activities.

4. Dietary fiber:

The effect of dietary fiber on the human body is first to promote gastrointestinal peristalsis, speed up the passage of food through the gastrointestinal tract, reduce absorption, and insoluble fiber absorbs water in the large intestine to soften the stool, which can play a role in preventing and treating constipation.

5. Vitamins:

Vitamins, some small amounts of organic compounds necessary for human and animal nutrition and growth, play an extremely important role in the metabolism, growth, development and health of the body. If there is a long-term deficiency of a certain vitamin, it will cause physiological dysfunction and certain diseases will occur. It is generally obtained from food.

There are a lot of ingredients in food, you say stress um, potassium acid and some more, um, bipolar bacillus and so on are all chemical components contained in it.

Salt, sodium chloride, characteristic salty.

MSG, monosodium glutamate, characteristic freshness.

Water, characteristically odorless, liquid, flowing.

1 True, 2 False, 3 False, 4 Don't Know, 5 Wrong, 6 Wrong, 7 Don't Know, 8 True, 9 Don't Know.

I'm sorry that I have limited ability

I'm a food professional, so I hope I can help you.

22 The effect of adding acid is that when the pH of the pectin solution is low enough, the carboxylate group is converted into a carboxylic acid group, so the molecule is not charged, the intermolecular repulsion decreases, the degree of hydration decreases, and the intermolecular association forms a gel. The purpose of sugaring: the higher the concentration of sugar, the more conducive to the formation of binding regions Influencing factors:

The content of soluble solids is affected by pH.

25 organic free chelates or complexes.

26 chloride ions.

28 copper, manganese, zinc.

29 fe zn cu se i mo co cr and the rest I think yours is right.

A salt-cured food, salt into the food liquid to produce a poor concentration, the formation of bacteria is not easy to grow environment, can be used as a preservative, salt has a salty taste, so salt can be used as a flavoring, can also be used as a food preservative, so a correct;

B Vitamin C, also known as ascorbic acid, mainly exists in fresh vegetables and fruits, "vitamin C" is easy to be destroyed when heated, should be taken cold raw food, or do not cook for too long, so B is correct;

c The human body does not contain enzymes that hydrolyze cellulose, so cellulose cannot be digested, so cellulose cannot be broken down to provide energy, so c is false;

d Soda is sodium carbonate, sodium carbonate hydrolyzed, CO3

2-+h2o?hco3

oh-，hco3

h2o?H2CO3+OH- solution is alkaline, according to the blue information of anthocyanins in grapes in alkaline environment, it can be seen that if it is fake red wine, there is no glucose, it will not be blue, so baking soda can be used to test fake red wine, so d is correct;

Therefore, C

nahco3

Cuso4Fe is easy to identify and understand: toxic and harmful to the body Similar structures have similar chemical properties.

Iron powder produces ferric ions under the action of gastric acid, which is a nutrient ion for blood replenishment, which is widely present in the body2Carbonates are broken down into non-toxic CO2 and water 3 by the action of gastric acidSodium bicarbonate has poor thermal stability and unstable structure.

Organic food is also called ecological or biological food. Organic food is a relatively unified reference to pollution-free natural food on the current national standard. Organic food usually comes from organic agricultural production systems and is produced and processed in accordance with international organic agricultural production requirements and corresponding standards.

In addition to organic food, at present, some derivative products such as organic cosmetics, textiles, forest products or organic food production materials are also provided by the international market, including biological pesticides, organic fertilizers, etc., which are collectively referred to as organic products after certification.

So, "organic" here is not a chemical concept – the presence of carbon in a molecule – but rather an organic way of farming and processing. Organic food refers to food that is produced and processed in this way; The products meet international or national organic food requirements and standards; All agricultural and sideline products and their processed products certified by the national organic food certification agency, including grains, jujubes, fungi, vegetables, fruits, dairy products, livestock products, honey, aquatic products, seasonings, etc.

Preservatives, pigments, flavors and other substances belong to food additives; Desiccants are used to absorb water vapor in food and are not food additives

Therefore, choose D