CHANGWEN is a Chinese stainless steel cookware manufacturer and has been in touch with cookware for more than 20 years, and today we are revealing something you may not know.

1.Introduction

Stainless steel cookware, is the use of stainless steel steel sheet, through cutting, deep drawing, composite bottom welding, polishing, binding handle, laser marking and a series of processes to complete the production of kitchen cookware.
Stainless steel cookware has the advantages of beautiful appearance, delicate structure, durability, corrosion resistance, rust prevention, easy processing, no deformation and so on. It is a mainstream product in the cookware market.

2. Types of stainless steel cookware

Stainless steel can make a very rich type of cookware, basically includes the life of the required cookware. These include frying pan, pan, soup pot, casserole, steamer, wok, baking pan, pressure cooker and so on.
In terms of function, they are divided into non-stick pans and regular pans. Non-stick cookware is divided into glossy coating and honeycomb surface coating, honeycomb better protection of the coating, cooking spatula basically can not touch the coating, can play a role in extending the use of the coating.

3. What are the advantages and disadvantages of stainless steel, aluminium, cast iron, non-stick, ceramic, iron and copper pans?

Before understanding the pot we first look at the characteristics of the materials needed to make the pot.

1.Advantages and disadvantages of various materials

Copper pots and pans
Advantages: It can be used for cooking, and to a certain extent, it can replenish the copper element for the human body. At the same time, after cooking, the taste of the dish will be changed to a certain extent, and it is more delicious.
Disadvantages: copper in a humid environment is easy to generate copper hydroxide carbonate, and oxidation reaction with the air, resulting in copper oxide, and in the cooking due to friction and the generation of copper and tin elements, to a certain extent, will cause some damage to human health.

Aluminium
Advantages: cheaper, more uniform distribution of hot spots, and lighter weight.
Disadvantages: not burn-resistant, can not use high temperature for stir-frying or cooking with a metal spatula. Will lead to the dissolution of some of the dissolved material, dissolved aluminium after the human body is ingested for the body is unhealthy. And because the material is relatively soft, so a fall on a pit, relatively speaking, is not very practical.

Stainless steel pot
Advantages: clean, corrosion-resistant oxidation excellent hardness is also very strong, the general bump will not give it caused by what scar, easy to scrub properly maintained always with the new same.
Disadvantages: If long-term contact with acid, alkali substances, may produce chemical reactions.

Iron pot
Advantages: The biggest benefit is that it can help the body to make up iron. In the process of stir-frying and cooking, the iron pot will not produce dissolved matter, there will be no shedding of the phenomenon, even if there is a shedding of material, will not bring harm to the body, but also help the body to make up for iron.
Disadvantages: easy to rust, and the weight of the iron pot is also relatively heavy, it is easy to stick to the pan.

Cast Iron Skillet
Advantages: cast iron pots heat up quickly, can maintain the temperature of the food, suitable for long time low temperature slow cooking;
Disadvantages: thicker rings, rougher texture and easier to crack.

Non-stick pan
Advantages: easy frying, cold pots and cold oil are not sticky, less oil, making food cooking more convenient. The best non-stick performance are Teflon coating and ceramic coating.
Disadvantages: non-stick pan surface has a chemical coating, high temperature or permanent easy to fall off. So non-stick pan is not suitable for high temperature stir-frying. If the coating has peeled off and scratched, it is recommended to replace it.

Ceramic pan
Advantages: The body of the pan is generally thicker, better heat resistance, to maintain a high state of heat with a minimum of fire, so the ingredients in the soup pot is easy to cook through.
Disadvantages: Ceramic pots heat transfer rate is slower, only suitable for slow cooking slow pot. Porcelain itself is more fragile, so it is easy to have scratches if you bump into it.

4. Why stainless steel pot to compound bottom

Single-layer stainless steel thermal conductivity is poor, and austenitic stainless steel high purity without magnetic, are not directly used for induction cooker, want to use for induction cooker, you must do compound bottom.
Stainless steel pot composite structure is generally used in a very thin inner layer of 304 or 316, the outer layer of 430, the middle of the sandwich aluminium core or aluminium-copper-aluminium core structure.
Stainless steel three-layer composite bottom is good or five-layer good
A three-layer composite bottom is made up of three layers of stainless steel, aluminium and stainless steel, where the aluminium layer is in the middle and provides good heat transfer properties, while the stainless steel material makes it stronger and more durable. Compared to the five-layer composite base, the three-layer composite base is lighter and cheaper. It is suitable for daily cooking and simple dishes.
The five-layer composite bottom is more even in heating and cooling rate, more stable in temperature and more durable compared to the three-layer composite bottom. The structure of the five-layer composite base consists of a stainless steel layer, an aluminium layer, a copper layer, an aluminium layer and a stainless steel layer. The bottom 5mm aluminium layer provides good heat transfer properties, while the copper layer better absorbs and transfers heat, resulting in greater heat transfer capability of the 5-layer composite bottom cookware. If you want to control the cooking temperature accurately for high-temperature cooking or for dishes that take a long time to cook, a five-layer composite bottom cookware may be more suitable. Of course, a five-layer composite bottom is also considerably more expensive than a three-layer composite bottom.

5.Is it better to have a three-layer composite bottom or a five-layer stainless steel cookware?

A triple-layer composite bottom is made up of three layers of stainless steel, aluminium and stainless steel, where the aluminium layer is in the middle and provides good heat transfer properties, while the stainless steel material makes it stronger and more durable. Compared to the five-layer composite base, the three-layer composite base is lighter and cheaper. It is suitable for daily cooking and simple dishes.
The five-layer composite bottom is more durable compared to the three-layer composite bottom in terms of more even heating and cooling rates, more stable temperatures, and more durability. The structure of the five-layer composite base consists of a stainless steel layer, an aluminium layer, a copper layer, an aluminium layer and a stainless steel layer. The bottom 5mm aluminium layer provides good heat transfer properties, while the copper layer better absorbs and transfers heat, resulting in greater heat transfer capability of the 5-layer composite bottom cookware. If you want to control the cooking temperature accurately for high-temperature cooking or for dishes that take a long time to cook, a five-layer composite bottom cookware may be more suitable. Of course, a five-layer composite bottom is also considerably more expensive than a three-layer composite bottom.

6. Stainless steel cookware materials in detail

Stainless steel is a general term for chromium alloys, not a single reference to a stainless steel, stainless steel used in various industries up to hundreds of kinds of stainless steel.
Stainless steel is divided into metallurgical organisation: martensitic steel, ferrite steel, austenitic steel, austenitic – ferrite (duplex) stainless steel and precipitation hardening stainless steel.
a. Austenitic stainless steel: as the name implies, it is a stainless steel with austenitic organisation at room temperature. Containing Ni 8% ~ 10%, Cr about 18%, C about 0.1%, with a stable austenitic organisation. Austenitic stainless steel is non-magnetic and has high toughness and plasticity. 201, 202, 301, 304, 316, 309, 321, etc. are austenitic stainless steel. Because austenitic stainless steel has comprehensive and good overall performance, it has been widely used in various industries.

b. Ferritic stainless steel: ferrite organisation is the main stainless steel in the state of use. It has a body-centred cubic crystal structure, and the chromium content is 11%~30%. Generally does not contain nickel, sometimes also contains a small amount of Mo, Ti, Nb and other elements, with a large coefficient of thermal conductivity, coefficient of expansion is small, good oxidation resistance, excellent resistance to stress corrosion and other characteristics, mostly used in the manufacture of water vapour, water and oxidizing acid corrosion-resistant parts. 429, 430, 433, 434, 435, 436, 439 belongs to the ferritic stainless steel.

c. Martensitic stainless steel: heat treatment can be adjusted through the mechanical properties of stainless steel, commonly known as a class of stainless steel can be hardened. Typical grades for Cr13 type. Higher hardness after quenching, different tempering temperatures with different toughness combinations, the standard martensitic stainless steel are: 403, 410, 414, 416, 416 (Se), 420, 431, 440A, 440B and 440C type.

d. austenitic – ferrite duplex stainless steel: austenitic and ferrite organisation of each about half of the stainless steel. Ni content of 3% ~ 10%, Cr content of 18% ~ 28%. Some steel also contains Mo, Cu, Si, Nb, Ti, N and other alloying elements. This type of steel has both austenitic and ferritic stainless steel characteristics, while also maintaining a ferritic stainless steel 475 ℃ brittle and high thermal conductivity, superplasticity and other characteristics. Duplex stainless steel has excellent pore corrosion resistance, is a nickel-saving stainless steel.

e. Precipitation hardening stainless steel: precipitation hardening stainless steel (precipitation hardening stainless steel) refers to the chemical composition of stainless steel on the basis of adding different types and quantities of reinforcing elements, through the precipitation hardening process precipitation precipitation of different types and quantities of carbides, nitrides, carbon-nitrides, and intermetallic compounds, not only to improve the strength of steel but also to maintain sufficient toughness of a class of steel. Maintain sufficient toughness of a class of high-strength stainless steel, referred to as PH steel. Precipitation hardening stainless steel according to its matrix metallurgical organisation can be divided into martensitic, semi-austenitic and austenitic type 3 categories.

Stainless steel is divided into: chromium stainless steel, chromium-nickel stainless steel and chromium-manganese-nitrogen stainless steel according to its composition.
a. Chromium stainless steel refers to stainless steel with high chromium content, which has good corrosion resistance.

b. Chromium-nickel stainless steel contains high chromium content, but also added a certain amount of nickel, improving the corrosion resistance and strength of stainless steel.

c. chromium manganese nitrogen stainless steel in addition to chromium and nickel, but also added manganese and nitrogen and other alloying elements, further improving the corrosion resistance of stainless steel.

7. Stainless steel pots and pans with what material

Stainless steel pots mainly use ferritic stainless steel and austenitic stainless steel.
a, ferritic stainless steel
430 and 443 stainless steel with magnetic conductivity, but the corrosion resistance is not as good as 304 stainless steel, mainly used to do pot composite bottom part.

b, austenitic stainless steel
201 stainless steel contains high manganese, easy to rust, poor corrosion resistance, the kitchen is mainly used in cheap dishes and cutlery.
304 (18-8, 18-10) is the mainstream of stainless steel kitchenware, with good rust and resistance.
304 (18-8, 18-10) in 18 on behalf of the chromium content, followed by 8, 10 on behalf of the nickel content, the higher the nickel content, the stronger the corrosion resistance. The national standard GB stipulates that 304 contains at least 8% above, so the common 304 stainless steel is also known as 18-8.
18-10 stainless steel is not 316 stainless steel, 18-10 stainless steel belongs to the 304 stainless steel, and the use of 316 grade is similar. The difference is that 316 contains molybdenum, 304 does not contain molybdenum, 18-10 stainless steel also does not contain molybdenum.
316 stainless steel than 304 nickel content is higher, and added molybdenum. Therefore 316 is more corrosion resistant than 304.

8. Stainless steel pot with or without magnetism

The main components of stainless steel pots and pans are chromium, nickel and steel. Nickel is a non-magnetic element, so compared with iron and steel, stainless steel with higher nickel content is generally not magnetic. However, stainless steel with higher steel content may be magnetised, at which point it can be attracted by a magnet. In general, the common market 304 stainless steel pots, 316 stainless steel pots and 201 stainless steel pots are not magnetic, but 201 stainless steel it can be magnetised by a magnet (magnetisation), while 430 and 4432 stainless steel pots have a certain degree of magnetism because of the higher steel content.
Without magnetism, the induction cooker can not be used, so you need to make a composite bottom.

9. Can a magnet verify the purity of stainless steel

Can a magnet adsorb a stainless steel pan to verify whether the stainless steel is pure 304 stainless steel, this is not all right.
Using a composite bottom stainless steel pot, there is a layer of 430, which is magnetic and will be adsorbed.

10. 304 stainless steel is food grade?

Not necessarily food grade. General stainless steel 304 is not able to meet the requirements related to food grade. If the surface of stainless steel 304 is marked with special symbols and words such as food grade, it is food grade. After all, general stainless steel contains lead and manganese content is generally high, and the content of these elements in food grade stainless steel can not exceed a certain standard. In addition, 304 stainless steel to achieve food grade standards, the production process must strictly control the proportion of arsenic, cadmium, nickel, chromium, lead and other metal materials precipitation.

11. Do stainless steel pans need to be opened?

Stainless steel pots in the manufacturing process there is a polishing process, in order to improve the speed and quality of polishing, will use abrasives containing grease and metal oxides, these grease and abrasives will remain in the stainless steel appearance and crevices, so stainless steel pots need to open the pot before use.

12. How to Season a Stainless Steel Pot?

1. Warm water + detergent to clean it.
2. Boil it in white vinegar + water and then clean it.
3. Use a soft cloth to dry the pot inside and outside, then open a small fire, pour the oil, spread evenly, put some vegetables to stir fry, last three or four minutes after the fire.
4. Wait until the pan is completely cool, clean it.
Note: Do not dry burn over high heat.

13.Maintenance tips

1. Can not be dry burning
Stainless steel pots and pans, although high temperature resistance, but still can not be long time dry burning, otherwise the material will be damaged, pots and pans deformation.
2. Stove fire is not too big
Stainless steel pots and pans of fast heat conduction, cooking with a small fire can be recommended not to exceed the range of the bottom of the pot, if the pan, the stove fire shall not exceed the height of the pot.
3. Must be cooled down before cleaning
Many people are used to just finished cooking pots and pans rushed cold water to cool down, but the temperature change may be too large instantly so that the stainless steel pot material damage, or even deformation. It is recommended to let the pot cool down before cleaning, if you need to clean immediately, you must switch to hot water.
4. Use soft sponge to brush
Even if the stainless steel pots are not as fragile as non-stick pots, it is still recommended to use a soft sponge to scrub, because steel brushes and dishcloths are prone to scratches on the surface of the pots and pans, losing the original mirror luster, and dirt may be stuck in the gaps, which makes it difficult to clean.
5. Dry immediately after cleaning
To avoid water stains on the surface of beautiful pots and pans, remember to wipe dry immediately after cleaning, you can keep the surface of the pots and pans shiny; in addition, it is also recommended that the bottom of the pots and pans before heating the water wipe off, so as not to let the pots and pans yellow, burned black. If the pan surface has produced a brownish-yellow water stains, you can use a sponge dipped in lemon juice or vinegar to gently brush the stains can be removed.
6. Do not add salt to cook for a long time
In the process of using stainless steel pots, can not directly put salt into the pot, so as not to corrode the body of the pot and produce white spots, salt in the final stage of cooking and then put, can be effectively avoided.

14.Common Problems

1. How to clean stainless steel pots and pans with limescale?
Stainless steel pots and pans used for a period of time after the accumulation of a layer of white scale.
First, add a certain amount of water in the pot, and then add vinegar at a ratio of 10%, and then put a small spoon of baking soda, boil for a period of time limescale naturally removed. Or use citric acid with water to boil can also remove scale.
2. How to clean stainless steel pots and pans?
Sprinkle baking soda on the bottom of the pot, pour a little white vinegar, let it sit for half an hour, and then wipe it clean with a rag.
3. Stainless steel pots and pans burnt black how to clean?
Squeeze a spoonful of detergent into an empty cup, then pour in 2 spoons of tomato sauce and 3 spoons of water, mix well, apply to the cutlery, use a small brush to brush the non-glossy place, soak for 10 minutes. Finally, rinse well with water.

15. Stainless steel cookware summary

Stainless steel cookware have been widely used in cooking, enough to prove its practicality and relative safety. Pay attention to the operation and maintenance in the process of use, stainless steel cookware are cookware that can be used for a long time.