The basic production process of bread is as follows: raw and auxiliary materials processing and blending-first kneading-first fermentation-second dough preparation-second dough treatment-second fermentation-shaping-pre-baking-baking-cooling-(semi-finished product processing) packaging-finished product. Processing procedures and precautions for raw and auxiliary materials are as follows:

1, flour processing:

Temperature control, according to the different regions and seasons, flour should be placed in a suitable environment for temperature control before use to make it more suitable for processing requirements. In winter, flour should be put in the production workshop or a warmer place a few days in advance, which can increase the temperature of flour and promote the fermentation speed of yeast when it is used. In summer, flour should be stored in a low-temperature and dry place, and it should be well ventilated to keep the flour at a suitable temperature and suitable for use, and to extend the shelf life of flour. Sieve. The flour must be sieved before use. If possible, use a metal detector for safety inspection to prevent metal objects from being stored. At the same time, sieving can prevent other impurities from infiltrating into the flour, and can also break the flour dough through sieving to make the powder finer and mix more gas, which is beneficial to the growth and reproduction of yeast.

2. Treatment of yeast:

Yeast itself is a kind of bioactive bacteria, and it is a kind of biological loosening agent for making bread. Its quality and activity have an important influence on bread production. The pretreatment of yeast is also closely related to the quality of products. The pretreatment method of yeast is as follows: Before use, active dry yeast can be dissolved in water at a proper temperature, and then mixed with dough, but the water temperature should not exceed 60 degrees Celsius, and greasy or high-concentration salt solution and sugar solution should not be mixed, because salt and sugar are antibacterial substances.

Fresh yeast should be taken out of the freezer 4 to 5 hours before use to soften it and gradually restore its vitality. Then it is stirred and dissolved with warm water of more than 5 times and about 25 degrees, and can be put into use after 5 minutes. It is worth noting that fresh yeast taken out of the freezer should be immediately soaked in water to dissolve, because excessive temperature difference will lead to the death of some yeast cells.

3. Sugar: White sugar is generally used to make bread. Sugar belongs to crystals, so it should be stored in a cool and dry place to prevent a large number of crystal blocks from being produced and getting wet. When making bread, it is best to dissolve it in water before feeding, so as to prevent yeast cells from shrinking and dying due to the reverse osmosis of granular crystalline sugar, which will affect the vitality of yeast. 4. Grease: The grease added to the dough during the bread making process is mostly solid grease, generally natural butter, pure animal butter, lard, margarine, hydrogenated ghee, etc. Because liquid oil (except liquid ghee) has great fluidity, and it will form an oil film around protein molecules and yeast cells in dough, which will affect the water absorption and expansion of protein and the metabolic function of yeast, so the above solid oil should be used in bread production.

Second, the preparation of dough

Dough preparation is to prepare processed raw materials into dough suitable for processing performance according to the dosage of formula and standard feeding procedure. The feeding procedure of dough is generally determined according to fermentation methods, which include primary fermentation, secondary fermentation and tertiary fermentation. At present, the dough for making bread in China mostly adopts the secondary fermentation method, also known as the middle seed method. Dough preparation and dough fermentation are two closely related processes, and they are also two key factors affecting bread quality and yield. When making dough, there are many factors that will affect its quality:

1. Effect of water on dough: When making bread, the amount of water is second only to that of flour, which is between 45% and 65%. When making dough, water must be in direct contact with flour, so that protein in flour can fully absorb water and form a large amount of gluten, forming gluten shelf and bubble film. Water consumption not only directly affects the output of bread, but also affects its quality and shelf life. Different bread varieties and different types of flour also have different water absorption. The PH value and mineral content of water are closely related to dough making, and the optimum PH value is 5-6. Too high pH value will affect the water absorption of protein and the extensibility of dough, and will also prolong the fermentation time. Water temperature is an important means to control the suitable fermentation temperature of dough. The optimum temperature of dough relaxation and basic fermentation is 25-28 degrees Celsius, and the optimum temperature of final fermentation is about 38 degrees Celsius. At the same time, controlling water temperature is the main means to control dough temperature, and dough temperature is an important factor affecting the quality of its fermentation process.

2. Proper control of dough mixing degree: The control of dough mixing degree is another important factor affecting bread quality. Because the dough is not fully stirred and spread, the gas retention is poor, the finished product is small, the internal structure is rough, the color is not good, the organizational structure is uneven, the dough is hard, and it is easy to peel when forming, and the finished product collapses; If it is stirred too much, the skin will become wet and sticky, which is not conducive to shaping and operation. The finished product has small volume, rough internal structure and poor quality.

3. Influence of auxiliary materials: The influence of auxiliary materials on the quality, flavor and texture of bread is also critical. Sucrose: When making the same soft and hard bread, every 5% increase in sucrose will reduce the water absorption of flour by 65,438+0%. The increase of sucrose content in dough will slow down the water absorption rate of flour and prolong the mixing time. At the same time, sugar can also inhibit bacteria and improve the color and flavor of bread. Salt: It can increase the elasticity of dough, increase flavor, inhibit the growth of bacteria and control yeast fermentation. Because adding salt too early will prolong the mixing time and hinder the formation of gluten, it is best to add salt when the gluten reaches 80% to 90%.

Milk powder: adding skim milk powder to dough can increase water absorption, because skim milk powder absorbs water slowly, which will definitely prolong the mixing time of dough. At the same time, milk powder can also play an emulsifying role, making bread softer and increasing flavor. Eggs: At present, most of the eggs added in domestic bread making are fresh eggs, which can be mixed with sugar and water to make bread softer and improve color and flavor. Modifiers: can be divided into chemical modifiers and biological modifiers. At present, chemical improvers are widely used, which can be directly mixed with flour to improve the internal structure of bread, increase the volume of bread and delay the aging time of bread.