Explanation of secondary fermentation of flour There are two views about secondary fermentation.
Firstly, flour, warm water and yeast are mixed in a proper proportion to form dough, and the dough is placed in an environment of about 30 degrees for 2-3 hours. When the volume increases by about 3 times, it is called primary fermentation. The fermented dough is made into steamed bread, flower rolls, steamed bread and other pasta, and then it is left standing for about 20 minutes to become large-volume secondary fermentation.
The second is to ferment the dough (batter) once and stir the dry flour again.
How long does it take for flour to ferment for the second time? The final fermentation is usually about 40 minutes.
Primary fermentation, intermediate fermentation and secondary fermentation.
Unless we are in a hurry, we can stir the dough, shape it, ferment it once and bake it. At other times, secondary fermentation is needed. Because the product fermented once, no matter its texture or flavor, can't be compared with the product fermented twice.
In the professional field, primary fermentation and secondary fermentation have two special words to reflect their differences (fermentation and proofing), while in home making, we only need to know that delicious bread is made by secondary fermentation.
Long-term fermentation will increase the flavor of bread, so some recipes use refrigerated fermentation, and through long-term fermentation at low temperature, bread with unique taste can be obtained. However, cold storage fermentation has a disadvantage, that is, the fermentation time is not well controlled, which easily leads to over-fermentation or under-fermentation. In modern times, this shortcoming has been solved, that is, the cold storage fermentation is combined with the middle seed method, and the simple cold storage fermentation method is no longer used. At this point, I will make a detailed blog post about the laws of China in the future.
The first fermentation, how to judge that it has been fermented?
The dough of ordinary bread can generally be fermented to 2-2.5 times the size. If you dip your finger in flour and poke a hole in the dough, the hole will not retract. If the dough around the hole collapses, it means that it is over-fermented.
Fermentation time is related to the sugar content, oil content and fermentation temperature of dough. Generally speaking, ordinary dough needs about 1 hour at 28 degrees. If the temperature is too high or too low, the fermentation time should be shortened or extended accordingly.
After the first fermentation, we need to lose weight on the dough Let the fat dough out and let it go back? Thin? Down, and then, cut into the required size, knead into smooth balls, and carry out intermediate fermentation.
In the middle of fermentation, I woke up again. The purpose of this step is for the next plastic surgery. Because if it is not proofed, the dough will be difficult to stretch, which will bring trouble to dough forming.
Intermediate fermentation can be carried out at room temperature, usually 15 minutes.
After the intermediate fermentation is completed, we can shape the dough into the required shape. This is also a very important one, which directly determines whether the bread you make is beautiful enough. The shaping method of each kind of bread is different, and you can follow the recipe. It should be noted that all the gases in the dough must be paid attention to when molding. As long as there is gas left in the dough, it will eventually become a big hole when baked.
The second fermentation (also called final fermentation) is generally required at a temperature of about 38 degrees.
In order to keep the dough from losing water, there should be more than 85% humidity.
Many TX asked me how to keep this temperature and humidity condition. Industrial production has a special fermentation box. However, there is no such condition for home cooking, so we have to settle for the second best and try our best to create a similar environment: arrange the dough on the baking tray, put it in the oven, put a plate of boiling water at the bottom of the oven and close the oven door. Water vapor will produce the required temperature and humidity in the enclosed space of the oven.
When using this method, it should be noted that when the boiling water is gradually cooled, if the fermentation is not complete, it needs to be replaced in time.
The final fermentation usually takes about 40 minutes. Ferment until the dough is twice as big.
What is the optimum temperature for dough fermentation? The optimum temperature for dough fermentation is 25 ~ 28℃ (which is the optimum temperature for yeast propagation). Propagation of asexual buds of yeast strains. In the process of reproduction, the empty cells of the mother nucleus produce a tubule called the intermediate sulcus. This tube rises to the surface of the cell, producing a protrusion through the cell wall, that is, a bud mark. Bud marks gradually grow up and fill the cytoplasm and nucleus of mother cells. When the nucleus grows as big as the mother cell, the mother cell nucleus is divided into two parts, and the two cells are completely located. The centrosome of the cell is far away, at this time, the mother cell and daughter cell have been completely separated, resulting in new bud marks respectively. When the temperature is 4℃, the yeast will reproduce for 20 hours. With the increase of temperature, the generation cycle is shortened. When the temperature is 23℃, the generation cycle of yeast is only 6 hours.
At 60℃, the yeast died.
When making dough, it is inevitable to mix mixed bacteria such as lactic acid bacteria and acetic acid bacteria. The optimum reproductive temperature of lactic acid bacteria is 35℃,
pay attention to
If the fermentation temperature is higher than 30℃, lactic acid bacteria and acetic acid bacteria will multiply, which will inhibit the reproduction of yeast and make the dough sour, so the dough fermentation temperature should be controlled at about 25 ~ 28℃. (* * Note * *: Use the fermentation function of the oven carefully. Yesterday I fermented in the oven and added water to the box. Even if the temperature is adjusted to the lowest oven temperature, it will reach 50 degrees)
Signs of dough fermentation maturity:
1 The top of the dough is bulging, but it feels dry. When you lift it with your hands, the dough is naturally elongated. Once you let go, it will slowly retract.
2. There are many pores in the group.
3. Wine aroma.
There is something wrong with dough fermentation: