First, excessive protein transport.

Egg white is the most critical and error-prone step in making Qifeng cake or cake roll. To what extent should protein be delivered?

Qifeng cake and cake rolls are delivered to different degrees. Qifeng often requires them to be sent to neutral foaming to dry foaming (any state in the middle will do), that is to say, when the eggbeater is mentioned, the protein will be hooked up, long and short, so that Qifeng can have better puffing power, rise higher, and the tissue will be more delicate, softer and fluffy.

But for the cake roll, because it needs to be rolled up, and the cake roll is not as thick as Qifeng, so the cake roll only needs to be sent to a neutral and wet state. That is to say, when it comes to the eggbeater, the protein hangs on it.

The cake roll made in this way is moist and not easy to crack. After the batter is poured into the baking tray, shake the baking tray a few times, and it will basically be smooth. If you overdo it, the cake roll will swell easily, because the puffing force is too strong, and then it will become difficult to roll up: it will crack easily.

Second, the egg yolk paste and protein are not evenly mixed.

You can try to open the baked cake slices and see if there is a different color from other cake organizations at the bulging place. There is no mixed egg white, and it is still a white piece after baking. If so, it can be judged that this is the reason.

Without mixing, there are two possibilities:

First, if there are too many protein, it is easy to make it difficult to mix well. It may not be visible to the naked eye, but there are many small pieces of protein in the batter that are uneven. It's possible that there is a relatively large piece of protein in the middle, so this piece swells badly, which is different from other batter and will naturally swell.

Second, I am afraid of defoaming and dare not mix more. In fact, if you pay attention to the technique and the cleanliness, water and oil of all the utensils you make, in fact, the protein cream is not as "fragile" as you think. Let's look at the mixing technique:

That is, the scraper strokes the basin from 12 to 6 o'clock. After that, it scoops up the batter at the bottom and then falls naturally. At the same time, rotate the basin with the other hand 180 degrees (practical operation, you will be skilled after practicing a few more times). )

Finally, the prepared Qifeng batter should be thick and even, and it can fall like a ribbon.

Generally, flour bumps that are not well stirred do not protrude from the epidermis, but are hidden in the cake body. When they are broken, they are hard powdery bumps. In your third picture, there are many bubbles on the surface, so I think most of them may be that the pastry is not evenly mixed with the egg yolk paste.

Third, there is something wrong with the oven temperature.

Can you turn the cake roll upside down and look at the back, that is, the towel surface, with the same color? Or is the bulge in the middle shallower than other places? If it is serious, even the middle piece will be a little inward.

This result is caused by the same reason as the concave bottom of Qifeng cake. The concave bottom of Qifeng cake is often accompanied by a very high uplift and cracking of the upper part of the cake. It is very similar to a cake roll.

So what is the reason?

Some friends will say that it is caused by the high temperature of the fire. You can say that, but not all. The reason is that in the process of expansion, the overall expansion speed is greater than the solidification speed of the bottom cake batter, and the bottom has not been finalized, so it is "pulled" and naturally concave upwards.

So how to solve it? If the overall temperature is suitable, it is necessary to raise the bottom material so that the bottom will condense and stick faster so as not to be pulled up. Of course, if the overall temperature is already high, it can only be lowered ~

Another possibility is that the temperature in your oven is uneven. However, the general household ovens are more or less uneven, as long as the temperature difference is not particularly large, it will not cause bulging. So you must see other types of snacks before baking. Is there such a situation that some places have been baked and colored, and some places are not even cooked?

Fourth, about the amount of your batter.

I think it's a little too much. Qifeng cake, no matter what mold it is, should be filled with 7 points at most, because its swelling power is really strong. The extra batter will often come out of the mold and the shape will become very strange. You must have seen some mushroom tops on the cake: this is mostly caused by too much batter.

What is the bulging bag in the middle when baking cake rolls? The reason for the bulge in the middle of the cake roll is 2

Making skills of cake roll

First use low-gluten flour, and sift the low-gluten flour for later use. This step is to sift the flour as fine as possible to avoid the appearance of granular flour, which has a direct factor on the fineness of the cake baked in the later stage.

The second step, in the process of beating egg whites, we must control the beating degree of egg whites, add sugar for three times, beat the egg whites until they are long and hooked, then pour one-third of the egg whites into the egg yolks and stir them slightly, and then pour the stirred egg whites into the remaining egg whites and stir them evenly, but not too much to avoid defoaming.

The phenomenon of bubbling in the middle of the cake roll may be that the egg white and yolk are not fully mixed when stirring.

Step 3: Pour the stirred mixture into the mold, smooth it with a scraper, and then lift the template on the table to vibrate properly, so that the gas in the mixture can be exhausted, so that the baked cake will reduce the internal cavities.

What is the bulging bag in the middle when baking cake rolls? The reason why the cake roll bulges in the middle is 3

The practice of cake rolls

Ingredients: 3 eggs, 30g milk, 30g sugar, 30g egg white, yolk 10g, 25g oil (corn oil is the best) and 40g low-gluten flour.

1. Separate the egg white from the yolk. Make sure that the egg white basin is dry, without water or oil. Add three or five drops of white vinegar to the egg white (this will remove the fishy smell of the egg) and put it in the refrigerator for later use.

2. Find another basin, put oil, sugar and milk, stir well, add low-gluten flour, continue to stir well, and finally add egg yolk. This is the post-egg method, so the cake will be soft.

3, take out the protein, with electric egg beater sent, prepare 30 grams of sugar. When the pot is filled with big bubbles for the first time, add a little sugar. If there is no special gram, add a little less first and continue to send it; Add sugar for the second time until the foam is fine and the protein becomes more, and continue to beat; Beat until it has lines and becomes ivory white. Add all the sugar and continue stirring until the protein thickens. At this time, slow down, stop the eggbeater from time to time, pick it up and see the state of the egg white until there is a big corner.

4. Preheat the oven to 170 degrees. Scoop one-third of the egg whites into the yolk with a spatula and draw a "Z" to stir, or as long as it is not clockwise or counterclockwise. After stirring, add the remaining half to the egg yolk until there is no egg white. After stirring as before, pour all the batter back into the remaining egg whites and stir evenly in the same way.

5. Pad the square baking tray with oil paper, pour in the batter, shake it a few times to foam, and bake it in the oven. /kloc-bake at 0/70 degrees for 20 minutes.

6. When the cake embryo is cold, you can make a roll. Lay the cake embryo flat, coat it with cream or jam, and coat it thicker, which will be fuller and taste better with the cake embryo. Or just roll it up and make the original cake roll without painting anything. Some people like to roll with a rolling pin, and I like to roll directly by hand, which is more practical. Wrap it in oil paper and put it in the refrigerator for half an hour, then take it out and cut it into pieces to enjoy.