The best feature of bread is:Fermented foods. Fermentation is a crucial step in bread making, which directly determines the success of bread making. The attractive aroma and flavor of bread is the first to ferment.
In the past, it was believed that bread with a large number of auxiliary ingredients was a high-end product, and that rich auxiliary ingredients were also the best way to make delicious breadAs everyone learned more and more about bread and returned to the true taste of bread, they found that the aroma and deliciousness of bread came from fermentation.
Fermentation is the most important process in bread making, but it is also the most difficult to master, elusive, and even avoidable.
Steps of fermentation Fermentation can be divided into three steps: primary fermentation, secondary fermentation, and tertiary fermentation.
One fermentationIt is located between stirring and splitting, and the purpose is to make the yeast more active.
Secondary fermentationIn the relaxation stage after splitting, the purpose is to facilitate shaping and adjust the state of the dough lacking gluten.
Triple fermentationThis stage is the process of starch decomposition, which is broken down by yeast enzymes into carbon dioxide and sugar, which determines the size and shape of the bread.
Many bread novices' understanding of fermentation is simply to judge the fermentation state by pressing the dough with their fingers.
In fact, fermentation is also a scientific system, and there are many factors that affect bread fermentation, and the following is a list of some factors that affect dough fermentation.
Raw materials that affect fermentation
flour
Amylase
The activity of the enzyme, which is the amount of amylase present in the flour. The more amylase enzymes are contained in flour, the faster the starch will be converted into maltose.
The amount of amylase changes depending on the conditions under which the wheat is harvested.
In wet years, wheat contains a high percentage of water and tends to germinate, so it produces more amylase. However, this has a downside for bakers: the bread is colored too quickly in the oven.
In very dry years, flour has a weaker ability to produce enzymes.
Extraction rate
Based on small-scale measurements, flours with a high extraction rate (e.g., T150) appear to ferment faster than flours with a lower extraction rate (e.g., T55).
The quality of gluten
The good elasticity and tightness of gluten make the bread expand well.
Proteins
In order to make high-quality bread, it is important to maintain the structure of the gas while using baker's yeast to produce strong gas, and the quality and quantity of protein in the flour are the key to gas retention.
If the protein is good and abundant, the stronger the gas retention, which also requires correct stirring.
Even if there is more protein, the gas retention of ** flour is not good, and the low-gluten flour in the first-class flour is also very weak.
Yeast
Number of yeast
Yeast plays a decisive role in the fermentation of bread, but care should be taken with the amount used. When yeast is added to the dough, the yeast can absorb the nutrients in the dough to grow and reproduce, and produce carbon dioxide gas, so that the dough forms a expanded, soft, honeycomb-like tissue structure.
The amount of yeast determines the rate at which sugar is broken down into carbon dioxide and therefore the bread in size.
If the dosage is too much, the gas production in the dough increases, and the porous wall in the dough becomes thinner rapidly, and the dough has good gas holding capacity in a short time, but after the time is extended, the dough quickly matures and becomes poor.
Baker's yeast is formulated in a large amount, but if the recipe does not contain sugar, it will produce gas sharply only in the first half, and the overall gas production is not much different from that of using a small amount of yeast.
Baker's yeast produces a lot of gas in the front and a lot of gas in the back, or the two balance the finished product, depending on the type of bread, so it must be used skillfully according to the method of making different breads.
Therefore, the amount of yeast should be determined according to the quality of gluten and the needs of the product. In general, the dosage of fresh yeast is 3 4 of the amount of flour, and the dosage of dry yeast is 1 of the amount of flour5％～2％。
Yeast quality
Yeast is viable, but if not stored properly, it can also lead to the death of yeast; It is important to take care that it is well preserved, so that it does not lose a large part of its fermentation power.
How to mix yeast into flour
Dry yeast is best mixed with water in advance, and fresh yeast is crushed before being added to the flour, these small details can speed up the yeast's work.
Salt
Salt can increase the density of gluten in the dough, enhance elasticity, and improve the gluten strength.
By increasing or decreasing the amount of salt, the fermentation rate can also be adjusted. A large amount of salt will affect the vitality of the yeast, and excessive salt will slow down the fermentation; When there is a shortage of salt, fermentation accelerates.
Although the dough without salt ferments quickly, the fermentation is extremely unstable, and it is easy to over-ferment, and the fermentation time is difficult to master. If there is a lack of salt in the dough, the dough will collapse after proofing.
Therefore, the amount of salt is generally 1 22％。
water
Water is an important raw material for bread production, and its main functions are:The protein in the flour absorbs water fully and forms a gluten network; The starch in the flour is gelatinized by heat and water absorption; Promote amylase to decompose starch and help yeast grow and reproduce.
Although the right amount of water is best, the gas retention of hard dough is better than that of soft dough; The gluten of the hard dough is tough and can withstand carbon dioxide better, and the bread does not expand as much.
The starch hydration of the soft dough is good, and the enzyme action is active, which is conducive to the expansion of the breadGluten in soft dough has better ductility; The disadvantage is that the relative physical properties are low, and it is difficult to hold the gas for a long time.
The four basic ingredients of bread dough are closely related and indispensable, and their interaction is where the principle of dough fermentation lies. Other excipients (such as sugar, oil, milk, eggs, improvers, etc.) not only have the effect of improving flavor and increasing nutritional value, but also have a certain auxiliary effect on fermentation.
Sugar
Sugar is the energy that supplies yeast**, and when the sugar content is less than 5, it can promote fermentation, and more than 6 will inhibit fermentation and slow down the fermentation.
oil
Oil can lubricate the fermented dough, making the volume of bread products bulky and loose; Among the types of fats, ghee is the best, while liquid oils such as salad oil are the worst. In order for the fat to be evenly distributed across the entire gluten, at least 4-5% should be added.
Eggs, milk
Eggs and milk can improve the tissue structure of fermented dough, increase gluten strength, improve gluten holding capacity and fermentation endurance, make dough more swelling, and at the same time supply yeast nutrients and improve the vitality of yeast.
In dairy products, as long as the protein contained in one of them is physically bound to the protein in the flour, it strengthens the gas retention, but on the other hand, if the pH value does not decrease, it will lose its stability.
Factors influencing fermentation
Temperature
Dough temperature:
At the end of the stirring, the dispensing temperature is preferably 24 to 26.
Room Temperature:
Temperature differences must be avoided, and fermentation needs to be consistent or the gluten will be damaged, and when the gluten cannot withstand it, it will deform very quickly.
Humidity
The state of indoor air humidity is determined by the amount of moisture in the air. The higher the temperature of the air, the greater the amount of water vapor that the air can retain, and vice versa, if the temperature of the air decreases and the amount of water vapor is too heavy, the water vapor is converted into droplets, which flow along the wall.
This phenomenon is easily observed in bakeries, when a large amount of bread is taken out of the oven, steam escapes, and then small droplets appear in the windows and walls.
In the process of fermentation, mainlyThe stage of secondary fermentation on a fermented clothIt is important to maintain the humidity in the room and in the bread dough, so that the dough does not transport moisture to the air and the surface of the dough does not dry out, i.e. it does not crust.
On the contrary, ifIf the air humidity is too high, the dough will stick to the leavening clothIn this way, it will be more difficult to bake in the oven. Indoor air humidity will affect how fast or slow the dough expands, causing the dough to withstand the deformation caused by carbon dioxide, and the ductility will be stronger or weaker.
The humidity of the air suitable for bread fermentation is about 80%.
The pH of the dough
The pH is at 45~5.5 is the best way to keep the gas. Adding an appropriate amount of oxidant can dense the network structure of gluten and strengthen the retention of gas.
The gas generation and gas retention are both in parallel, and no matter which side is too strong or weak, it will not be able to bake a good bread.
Maintaining the peak of gas production and gas storage at the time of placing in the oven and within 7 minutes after placing it in the oven is the key to making high-quality bread.
It can be seen that there are many reasons why dough affects fermentation:The quantity and quality of yeast, the amount and type of sugar, the amount of starch, the temperature of the dough, the hardness of the dough, the type and amount of yeast food additives, the amount of salt, the pH value of the dough, the temperature, the humidityetc., these important factors. These important factors do not act separately, but produce CO2 in a complex context.
About fermentation, what confusion do you have, welcome to leave a message below, everyone together**!